Common use of Appointment of Depositary Clause in Contracts

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. 6 Section 2.2 Form and Transferability of ADSs. 7 Section 2.3 Deposit of Shares. 8 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Section 2.5 Issuance of ADSs. 10 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 Section 2.9 Lost ADRs, etc. 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Section 2.11 Escheatment. 14 Section 2.12 Partial Entitlement ADSs. 14 Section 2.13 Certificated/Uncertificated ADSs. 15 Section 2.14 Restricted ADSs. 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. 18 Section 3.2 Liability for Taxes and Other Charges. 18 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Section 3.4 Compliance with Information Requests. 19 Section 3.5 Ownership Restrictions. 19 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. 20 Section 4.2 Distribution in Shares. 21 Section 4.3 Elective Distributions in Cash or Shares. 22 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Section 4.7 Redemption. 25 Section 4.8 Conversion of Foreign Currency. 26 Section 4.9 Fixing of ADS Record Date. 27 Section 4.10 Voting of Deposited Securities. 27 Section 4.11 Changes Affecting Deposited Securities. 29 Section 4.12 Available Information. 30 Section 4.13 Reports. 30 Section 4.14 List of Holders. 31 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 8 Section 2.1 Appointment of Depositary. 6 8 Section 2.2 Form and Transferability of ADSs. 7 8 Section 2.3 Deposit of Shares. 8 10 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 11 Section 2.5 Issuance of ADSs. 10 12 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 14 Section 2.9 Lost ADRs, etc. 14 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 15 Section 2.11 Escheatment. 14 16 Section 2.12 Partial Entitlement ADSs. 14 16 Section 2.13 Certificated/Uncertificated ADSs. 15 16 Section 2.14 Restricted ADSs. 16 18 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 19 Section 3.2 Liability for Taxes and Other Charges. 18 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 20 Section 3.4 Compliance with Information Requests. 19 21 Section 3.5 Ownership Restrictions. 19 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 22 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 22 Section 4.2 Distribution in Shares. 21 23 Section 4.3 Elective Distributions in Cash or Shares. 22 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 25 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 27 Section 4.7 Redemption. 25 27 Section 4.8 Conversion of Foreign Currency. 26 28 Section 4.9 Fixing of ADS Record Date. 27 29 Section 4.10 Voting of Deposited Securities. 27 29 Section 4.11 Changes Affecting Deposited Securities. 29 31 Section 4.12 Available Information. 30 32 Section 4.13 Reports. 30 32 Section 4.14 List of Holders. 31 33 Section 4.15 Taxation. 31 33 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 34 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 34 Section 5.2 Exoneration. 32 35 Section 5.3 Standard of Care. 33 35 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 36 Section 5.5 The Custodian. 35 37 Section 5.6 Notices and Reports. 35 38 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 38 Section 5.8 Indemnification. 37 39 Section 5.9 ADS Fees and Charges. 38 40 Section 5.10 Pre-Release Transactions. 39 41 Section 5.11 Restricted Securities Owners. 40 42 ARTICLE VI AMENDMENT AND TERMINATION 40 42 Section 6.1 Amendment/Supplement. 40 42 Section 6.2 Termination. 41 43 ARTICLE VII MISCELLANEOUS 42 44 Section 7.1 Counterparts. 42 44 Section 7.2 No Third-Third Party Beneficiaries. 42 44 Section 7.3 Severability. 42 45 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 45 Section 7.5 Notices. 43 45 Section 7.6 Governing Law and Jurisdiction. 43 46 Section 7.7 Assignment. 45 48 Section 7.8 Compliance with U.S. Securities Laws. 45 48 Section 7.9 England and Wales Law References. 45 48 Section 7.10 Titles and References. 46 48 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 7 Section 2.2 Form and Transferability of ADSs. 7 Section 2.3 Deposit of Shares. 8 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 11 Section 2.5 Issuance of ADSs. 10 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 14 Section 2.9 Lost ADRs, etc. 14 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 15 Section 2.11 Escheatment. 14 15 Section 2.12 Partial Entitlement ADSs. 14 15 Section 2.13 Certificated/Uncertificated ADSs. 15 16 Section 2.14 Restricted ADSs. 16 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 19 Section 3.2 Liability for Taxes and Other Charges. 18 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 20 Section 3.4 Compliance with Information Requests. 19 21 Section 3.5 Ownership Restrictions. 19 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 22 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 22 Section 4.2 Distribution in Shares. 21 23 Section 4.3 Elective Distributions in Cash or Shares. 22 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 25 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 27 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 28 Section 4.7 Redemption. 25 28 Section 4.8 Conversion of Foreign Currency. 26 28 Section 4.9 Fixing of ADS Record Date. 27 29 Section 4.10 Voting of Deposited Securities. 27 30 Section 4.11 Changes Affecting Deposited Securities. 29 32 Section 4.12 Available Information. 30 32 Section 4.13 Reports. 30 33 Section 4.14 List of Holders. 31 33 Section 4.15 Taxation. 31 33 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 34 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 34 Section 5.2 Exoneration. 32 35 Section 5.3 Standard of Care. 33 35 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 36 Section 5.5 The Custodian. 35 37 Section 5.6 Notices and Reports. 35 38 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 39 Section 5.8 Indemnification. 37 40 Section 5.9 ADS Fees and Charges. 38 41 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 42 ARTICLE VI AMENDMENT AND TERMINATION 40 42 Section 6.1 Amendment/Supplement. 40 42 Section 6.2 Termination. 41 43 ARTICLE VII MISCELLANEOUS 42 44 Section 7.1 Counterparts. 42 44 Section 7.2 No Third-Third Party Beneficiaries/Acknowledgments. 42 44 Section 7.3 Severability. 42 45 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 45 Section 7.5 Notices. 43 45 Section 7.6 Governing Law and Jurisdiction. 43 46 Section 7.7 Assignment. 45 48 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 48 Section 7.9 England and Wales English Law References. 45 48 Section 7.10 Titles and References. 46 48 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE●], 20172020, by and among (i) NuCana Freeline Therapeutics Holdings plc, a public limited company incorporated under the laws of England and Wales Wales, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 7 Section 2.2 Form and Transferability of ADSs. 7 Section 2.3 Deposit of Shares. 8 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Section 2.5 Issuance of ADSs. 10 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 Section 2.9 Lost ADRs, etc. 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Section 2.11 Escheatment. 14 15 Section 2.12 Partial Entitlement ADSs. 14 15 Section 2.13 Certificated/Uncertificated ADSs. 15 Section 2.14 Restricted ADSs. 16 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. 18 Section 3.2 Liability for Taxes and Other Charges. 18 19 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Section 3.4 Compliance with Information Requests. 19 20 Section 3.5 Ownership Restrictions. 19 20 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 ARTICLE IV THE DEPOSITED SECURITIES 20 21 Section 4.1 Cash Distributions. 20 21 Section 4.2 Distribution in Shares. 21 22 Section 4.3 Elective Distributions in Cash or Shares. 22 23 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 25 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 26 Section 4.7 Redemption. 25 26 Section 4.8 Conversion of Foreign Currency. 26 27 Section 4.9 Fixing of ADS Record Date. 27 28 Section 4.10 Voting of Deposited Securities. 27 28 Section 4.11 Changes Affecting Deposited Securities. 29 31 Section 4.12 Available Information. 30 31 Section 4.13 Reports. 30 31 Section 4.14 List of Holders. 31 32 Section 4.15 Taxation. 31 32 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 33 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 33 Section 5.2 Exoneration. 32 34 Section 5.3 Standard of Care. 33 34 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 35 Section 5.5 The Custodian. 35 36 Section 5.6 Notices and Reports. 35 37 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 37 Section 5.8 Indemnification. 37 38 Section 5.9 ADS Fees and Charges. 38 39 Section 5.10 Pre-Release Transactions. 39 40 Section 5.11 Restricted Securities Owners. 40 41 ARTICLE VI AMENDMENT AND TERMINATION 40 41 Section 6.1 Amendment/Supplement. 40 41 Section 6.2 Termination. 41 42 ARTICLE VII MISCELLANEOUS 42 44 Section 7.1 Counterparts. 42 44 Section 7.2 No Third-Third Party Beneficiaries/Acknowledgments. 42 44 Section 7.3 Severability. 42 44 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 44 Section 7.5 Notices. 43 45 Section 7.6 Governing Law and Jurisdiction. 43 45 Section 7.7 Assignment. 45 47 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 47 Section 7.9 England and Wales The Cayman Islands Law References. 45 48 Section 7.10 Titles and References. 46 48 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE]___________, 20172018, by and among (i) NuCana plcCANGO INC., a public an exempted company with limited company incorporated liability organized under the laws of England and Wales the Cayman Islands, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. Depositary 6 Section 2.2 Form and Transferability of ADSs. 7 ADSs 6 Section 2.3 Deposit of Shares. Shares 8 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 9 Section 2.5 Issuance of ADSs. 10 ADSs 9 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 10 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. Securities 11 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 12 Section 2.9 Lost ADRs, etc. 14 13 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 13 Section 2.11 Escheatment. 14 Escheatment 13 Section 2.12 Partial Entitlement ADSs. ADSs 14 Section 2.13 Certificated/Uncertificated ADSs. ADSs 15 Section 2.14 Restricted ADSs. ADSs 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 17 Section 3.1 Proofs, Certificates and Other Information. 18 Information 17 Section 3.2 Liability for Taxes and Other Charges. Charges 18 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 18 Section 3.4 Compliance with Information Requests. Requests 19 Section 3.5 Ownership Restrictions. Restrictions 19 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 19 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. Distributions 20 Section 4.2 Distribution in Shares. Shares 21 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 21 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 22 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. Shares 24 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 24 Section 4.7 Redemption. Redemption 25 Section 4.8 Conversion of Foreign Currency. 26 Currency 25 Section 4.9 Fixing of ADS Record Date. 27 Date 26 Section 4.10 Voting of Deposited Securities. 27 Securities 26 Section 4.11 Changes Affecting Deposited Securities. Securities 29 Section 4.12 Available Information. 30 Information 29 Section 4.13 Reports. Reports 30 Section 4.14 List of Holders. 31 Holders 30 Section 4.15 Taxation. 31 Taxation 30 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 31 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Xxxxxxxxx 00 Section 5.2 Exoneration. Exoneration 32 Section 5.3 Standard of Care. 33 Care 32 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 33 Section 5.5 The Custodian. 35 Custodian 34 Section 5.6 Notices and Reports. 35 Reports 34 Section 5.7 Issuance of Additional Shares, ADSs etc. 35 Section 5.8 Indemnification 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Charges of Depositary 37 Section 5.10 Pre-Release Transactions. 39 Transactions 38 Section 5.11 Restricted Securities Owners. 40 Owners 38 ARTICLE VI AMENDMENT AND TERMINATION 40 39 Section 6.1 Amendment/Supplement. 40 Supplement 39 Section 6.2 Termination. 41 Termination 40 ARTICLE VII MISCELLANEOUS 42 41 Section 7.1 Counterparts. 42 Counterparts 41 Section 7.2 No Third-Party Beneficiaries. 42 Beneficiaries 41 Section 7.3 Severability. 42 Severability 41 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 41 Section 7.5 Notices. 43 Notices 41 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 42 Section 7.7 Assignment. 45 Assignment 44 Section 7.8 Compliance with U.S. Securities Laws. 45 Laws 44 Section 7.9 England and Wales Cayman Island Law References. 45 References 44 Section 7.10 Titles and References. 46 References 44 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).ADR A-1

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 8 Section 2.1 Appointment of Depositary. 6 Depositary 8 Section 2.2 Form and Transferability of ADSs. 7 ADSs 9 Section 2.3 Deposit of Shares. 8 Shares 10 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 12 Section 2.5 Issuance of ADSs. 10 ADSs 12 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 13 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 14 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 etc 15 Section 2.9 Lost ADRs, etc. 14 etc 16 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 16 Section 2.11 Escheatment. 14 Escheatment 16 Section 2.12 Partial Entitlement ADSs. 14 ADSs 16 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 17 Section 2.14 Restricted ADSs. 16 ADSs 18 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 20 Section 3.1 Proofs, Certificates and Other Information. 18 Information 20 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 21 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 21 Section 3.4 Compliance with Information Requests. 19 Requests 22 Section 3.5 Ownership Restrictions. 19 Restrictions 22 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 23 ARTICLE IV THE DEPOSITED SECURITIES 20 24 Section 4.1 Cash Distributions. 20 Distributions 24 Section 4.2 Distribution in Shares. 21 Shares 25 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 25 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 26 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 28 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 29 Section 4.7 Redemption. 25 Redemption 29 Section 4.8 Conversion of Foreign Currency. 26 Currency 30 Section 4.9 Fixing of ADS Record Date. 27 Date 31 Section 4.10 Voting of Deposited Securities. 27 Securities 31 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 33 Section 4.12 Available Information. 30 Information 34 Section 4.13 Reports. 30 Reports 34 Section 4.14 List of Holders. 31 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).34

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. Depositary 6 Section 2.2 Form and Transferability of ADSs. 7 ADSs 6 Section 2.3 Deposit of Shares. Shares 8 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 9 Section 2.5 Issuance of ADSs. 10 ADSs 9 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 10 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. Securities 11 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 12 Section 2.9 Lost ADRs, etc. 14 13 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 13 Section 2.11 Escheatment. 14 Escheatment 13 Section 2.12 Partial Entitlement ADSs. 14 ADSs 13 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 14 Section 2.14 Restricted ADSs. 16 ADSs 15 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 17 Section 3.1 Proofs, Certificates and Other Information. 18 Information 17 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 17 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 18 Section 3.4 Compliance with Information Requests. 19 Requests 18 Section 3.5 Ownership Restrictions. 19 Restrictions 18 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 19 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. Distributions 20 Section 4.2 Distribution in Shares. 21 Shares 20 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 21 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 22 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 23 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 24 Section 4.7 Redemption. 25 Redemption 24 Section 4.8 Conversion of Foreign Currency. 26 Currency 25 Section 4.9 Fixing of ADS Record Date. 27 Date 25 Section 4.10 Voting of Deposited Securities. 27 Securities 26 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 27 Section 4.12 Available Information. 30 Information 28 Section 4.13 Reports. 30 Reports 28 Section 4.14 List of Holders. 31 Holders 28 Section 4.15 Taxation. 31 Taxation 29 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 30 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Xxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 30 Section 5.3 Standard of Care. 33 Care 31 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 32 Section 5.5 The Custodian. 35 Custodian 32 Section 5.6 Notices and Reports. 35 Reports 33 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 34 Section 5.8 Indemnification. 37 Indemnification 35 Section 5.9 ADS Fees and Charges. 38 Charges of Depositary 35 Section 5.10 Pre-Release Transactions. 39 Transactions 36 Section 5.11 Restricted Securities Owners. 40 Owners 37 ARTICLE VI AMENDMENT AND TERMINATION 40 37 Section 6.1 Amendment/Supplement. 40 Supplement 37 Section 6.2 Termination. 41 Termination 38 ARTICLE VII MISCELLANEOUS 42 39 Section 7.1 Counterparts. 42 Counterparts 39 Section 7.2 No Third-Party Beneficiaries. 42 Beneficiaries 39 Section 7.3 Severability. 42 Severability 40 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 40 Section 7.5 Notices. 43 Notices 40 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 41 Section 7.7 Assignment. 45 Assignment 42 Section 7.8 Compliance with U.S. Securities Laws. 45 Laws 42 Section 7.9 England and Wales Spanish Law References. 45 References 43 Section 7.10 Titles and References. 46 References 43 EXHIBITS Form of ADR. ADR A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).Schedule B-1

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 7 Section 2.2 Form and Transferability of ADSs. 7 8 Section 2.3 Deposit of Shares. 8 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 11 Section 2.5 Issuance of ADSs. 10 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 14 Section 2.9 Lost ADRs, etc. 14 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 15 Section 2.11 Escheatment. 14 15 Section 2.12 Partial Entitlement ADSs. 14 15 Section 2.13 Certificated/Uncertificated ADSs. 15 16 Section 2.14 Restricted ADSs. 16 18 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 19 Section 3.2 Liability for Taxes and Other Charges. 18 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 20 Section 3.4 Compliance with Information Requests. 19 21 Section 3.5 Ownership Restrictions. 19 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 22 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 22 Section 4.2 Distribution in Shares. 21 23 Section 4.3 Elective Distributions in Cash or Shares. 22 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 25 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 27 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 28 Section 4.7 Redemption. 25 28 Section 4.8 Conversion of Foreign Currency. 26 28 Section 4.9 Fixing of ADS Record Date. 27 29 Section 4.10 Voting of Deposited Securities. 27 30 Section 4.11 Changes Affecting Deposited Securities. 29 31 Section 4.12 Available Information. 30 Section 4.13 Reports. 30 Section 4.14 List of Holders. 31 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).32

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 Depositary 7 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. 8 Shares 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 11 Section 2.5 Issuance of ADSs. 10 ADSs 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 etc 14 Section 2.9 Lost ADRs, etc. 14 etc 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 15 Section 2.11 Escheatment. 14 Escheatment 15 Section 2.12 Partial Entitlement ADSs. 14 ADSs 15 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 16 Section 2.14 Restricted ADSs. 16 ADSs 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 Information 19 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 20 Section 3.4 Compliance with Information Requests. 19 Requests 20 Section 3.5 Ownership Restrictions. 19 Restrictions 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 21 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 Distributions 22 Section 4.2 Distribution in Shares. 21 Shares 23 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 23 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 27 Section 4.7 Redemption. 25 Redemption 27 Section 4.8 Conversion of Foreign Currency. 26 Currency 28 Section 4.9 Fixing of ADS Record Date. 27 Date 29 Section 4.10 Voting of Deposited Securities. 27 Securities 29 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 32 Section 4.12 Available Information. 30 Information 33 Section 4.13 Reports. 30 Reports 33 Section 4.14 List of Holders. 31 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).33

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 8 Section 2.1 Appointment of Depositary. 6 Depositary 8 Section 2.2 Form and Transferability of ADSs. 7 ADSs 8 Section 2.3 Deposit of Shares. 8 Shares 10 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 11 Section 2.5 Issuance of ADSs. 10 ADSs 12 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 14 Section 2.9 Lost ADRs, etc. 14 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 15 Section 2.11 Escheatment. 14 Escheatment 16 Section 2.12 Partial Entitlement ADSs. 14 ADSs 16 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 16 Section 2.14 Restricted ADSs. 16 ADSs 18 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 Information 19 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 21 Section 3.4 Compliance with Information Requests. 19 Requests 21 Section 3.5 Ownership Restrictions. 19 Restrictions 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 22 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 Distributions 22 Section 4.2 Distribution in Shares. 21 Shares 23 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 25 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 27 Section 4.7 Redemption. 25 Redemption 27 Section 4.8 Conversion of Foreign Currency. 26 Currency 28 Section 4.9 Fixing of ADS Record Date. 27 Date 29 Section 4.10 Voting of Deposited Securities. 27 Securities 29 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 32 Section 4.12 Available Information. 30 Information 32 Section 4.13 Reports. 30 Reports 33 Section 4.14 List of Holders. 31 Holders 33 Section 4.15 Taxation. 31 Taxation 33 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 34 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Xxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 35 Section 5.3 Standard of Care. 33 Care 35 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 36 Section 5.5 The Custodian. 35 Custodian 37 Section 5.6 Notices and Reports. 35 Reports 38 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 38 Section 5.8 Indemnification. 37 Indemnification 39 Section 5.9 ADS Fees and Charges. 38 Charges 40 Section 5.10 Pre-Release Transactions. 39 Transactions 41 Section 5.11 Restricted Securities Owners. 40 Owners 42 ARTICLE VI AMENDMENT AND TERMINATION 40 42 Section 6.1 Amendment/Supplement. 40 Supplement 42 Section 6.2 Termination. 41 Termination 43 ARTICLE VII MISCELLANEOUS 42 44 Section 7.1 Counterparts. 42 Counterparts 44 Section 7.2 No Third-Party Beneficiaries. 42 Beneficiaries 45 Section 7.3 Severability. 42 Severability 45 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 45 Section 7.5 Notices. 43 Notices 45 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 46 Section 7.7 Assignment. 45 Assignment 48 Section 7.8 Compliance with U.S. Securities Laws. 45 Laws 48 Section 7.9 England and Wales Law References. 45 References 48 Section 7.10 Titles and References. 46 References 48 EXHIBITS Form of ADR. ADR A-1 Fee Schedule. Schedule B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE]October 2, 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 Depositary 7 Section 2.2 Form and Transferability of ADSs. 7 ADSs 8 Section 2.3 Deposit of Shares. 8 Shares 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 11 Section 2.5 Issuance of ADSs. 10 ADSs 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 etc 14 Section 2.9 Lost ADRs, etc. 14 etc 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 15 Section 2.11 Escheatment. 14 Escheatment 15 Section 2.12 Partial Entitlement ADSs. 14 ADSs 15 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 16 Section 2.14 Restricted ADSs. 16 ADSs 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 Information 19 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 20 Section 3.4 Compliance with Information Requests. 19 Requests 21 Section 3.5 Ownership Restrictions. 19 Restrictions 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 21 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 Distributions 22 Section 4.2 Distribution in Shares. 21 Shares 22 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 23 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 27 Section 4.7 Redemption. 25 Redemption 27 Section 4.8 Conversion of Foreign Currency. 26 Currency 28 Section 4.9 Fixing of ADS Record Date. 27 Date 29 Section 4.10 Voting of Deposited Securities. 27 Securities 29 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 32 Section 4.12 Available Information. 30 Information 32 Section 4.13 Reports. 30 Reports 33 Section 4.14 List of Holders. 31 Holders 33 Section 4.15 Taxation. 31 Taxation 33 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 34 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Rxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 35 Section 5.3 Standard of Care. 33 Care 35 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 36 Section 5.5 The Custodian. 35 Custodian 37 Section 5.6 Notices and Reports. 35 Reports 38 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 etc 38 Section 5.8 Indemnification. 37 Indemnification 39 Section 5.9 ADS Fees and Charges. 38 Charges 40 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 Owners 41 ARTICLE VI AMENDMENT AND TERMINATION 40 42 Section 6.1 Amendment/Supplement. 40 Supplement 42 Section 6.2 Termination. 41 Termination 42 ARTICLE VII MISCELLANEOUS 42 44 Section 7.1 Counterparts. 42 Counterparts 44 Section 7.2 No Third-Third Party Beneficiaries. 42 /Acknowledgments 44 Section 7.3 Severability. 42 Severability 44 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 44 Section 7.5 Notices. 43 Notices 45 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 46 Section 7.7 Assignment. 45 Assignment 47 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 Laws 47 Section 7.9 England and Wales English Law References. 45 References 48 Section 7.10 Titles and References. 46 References 48 Section 7.11 Amendment and Restatement 49 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 AMENDED AND RESTATED DEPOSIT AGREEMENT AMENDED AND RESTATED DEPOSIT AGREEMENT, dated as of [DATE●] [●], 20172020, by and among (i) NuCana Amryt Pharma plc, a public limited company incorporated under the laws of England and Wales Wales, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America America, and its successors (“Citibank”) acting in its capacity as depositarydepositary under the terms of this Deposit Agreement, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 Depositary 7 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. 8 Shares 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 11 Section 2.5 Issuance of ADSs. 10 ADSs 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 etc 14 Section 2.9 Lost ADRs, etc. 14 etc 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 15 Section 2.11 Escheatment. 14 Escheatment 15 Section 2.12 Partial Entitlement ADSs. 14 ADSs 16 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 16 Section 2.14 Restricted ADSs. 16 ADSs 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. Information 18 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 19 Section 3.3 Representations and Warranties on Deposit of Shares. Shares 19 Section 3.4 Compliance with Information Requests. Requests 19 Section 3.5 Ownership Restrictions. 19 Restrictions 20 Section 3.6 Reporting Obligations and Regulatory Approvals. Approvals 20 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. Distributions 20 Section 4.2 Distribution in Shares. Shares 21 Section 4.3 Elective Distributions in Cash or Shares. Shares 22 Section 4.4 Distribution of Rights to Purchase Additional ADSs. ADSs 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 25 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. Form 25 Section 4.7 Redemption. 25 Redemption 26 Section 4.8 Conversion of Foreign Currency. Currency 26 Section 4.9 Fixing of ADS Record Date. Date 27 Section 4.10 Voting of Deposited Securities. 27 Securities 28 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 30 Section 4.12 Available Information. 30 Information 31 Section 4.13 Reports. 30 Reports 31 Section 4.14 List of Holders. Holders 31 Section 4.15 Taxation. Taxation 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).32

Appointment of Depositary. FORM OF RECEIPTSRECEIPT; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 5 SECTION 2.1 Appointment of Depositary. 6 Section Depositary 5 SECTION 2.2 Form and Transferability of ADSs. Receipts 5 SECTION 2.3 Deposits 7 Section 2.3 Deposit SECTION 2.4 Execution and Delivery of Shares. Receipts 8 Section 2.4 Registration and Safekeeping SECTION 2.5 Transfer of Deposited Securities. 10 Section 2.5 Issuance of ADSs. 10 Section 2.6 Transfer, Receipts; Combination and Split-up of ADRs. 11 Section 2.7 Receipts 8 SECTION 2.6 Surrender of ADSs Receipts and Withdrawal of Deposited Securities. 11 Section 2.8 Securities 9 SECTION 2.7 Limitations on Execution and Delivery, Transfer, etc. of ADSsReceipts; Suspension of Delivery, Transfer, etc. 13 Section 2.9 10 SECTION 2.8 Lost ADRsReceipts, etc. 14 Section 2.10 11 SECTION 2.9 Cancellation and Destruction of Surrendered ADRsReceipts; Maintenance of RecordsRecords 11 SECTION 2.10 Maintenance of Records 11 ARTICLE III. 14 Section 2.11 Escheatment. 14 Section 2.12 Partial Entitlement ADSs. 14 Section 2.13 Certificated/Uncertificated ADSs. 15 Section 2.14 Restricted ADSs. 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section RECEIPTS 12 SECTION 3.1 Proofs, Certificates and Other Information. 18 Section Information 12 SECTION 3.2 Liability for Taxes and Other Charges. 18 Section Charges 12 SECTION 3.3 Representations and Warranties on Deposit of Shares. 19 Section Shares 13 SECTION 3.4 Compliance with Information Requests. 19 Section 3.5 Ownership Restrictions. 19 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Requests 13 ARTICLE IV THE DEPOSITED SECURITIES 20 Section SECURITIES. 14 SECTION 4.1 Cash Distributions. 20 Section Distributions 14 SECTION 4.2 Distribution in Shares. 21 Section Shares 14 SECTION 4.3 Elective Distributions in Cash or Shares. 22 Section Shares 15 SECTION 4.4 Distribution of Rights to Purchase Additional ADSs. 23 Section Shares 16 SECTION 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Section Shares 17 SECTION 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Section 4.7 Redemption. 25 Section 4.8 Conversion of Foreign Currency. 26 Section 4.9 Currency 18 SECTION 4.7 Fixing of ADS Record Date. 27 Section 4.10 Date 19 SECTION 4.8 Voting of Deposited Securities. 27 Section 4.11 Securities 19 SECTION 4.9 Changes Affecting Deposited Securities. 29 Section Securities 21 SECTION 4.10 Available Information 21 SECTION 4.11 Reports 22 SECTION 4.12 Available Information. 30 Section 4.13 Reports. 30 Section 4.14 List of Holders. 31 Section 4.15 Holders 22 SECTION 4.13 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).Withholding 22

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. 6 Section 2.2 Form and Transferability of ADSs. 7 Section 2.3 Deposit of Shares. 8 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Section 2.5 Issuance of ADSs. 10 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 Section 2.9 Lost ADRs, etc. 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Section 2.11 Escheatment. 14 Section 2.12 Partial Entitlement ADSs. 14 Section 2.13 Certificated/Uncertificated ADSs. 15 Section 2.14 Restricted ADSs. 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. 18 Section 3.2 Liability for Taxes and Other Charges. 18 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Section 3.4 Compliance with Information Requests. 19 Section 3.5 Ownership Restrictions. 19 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. 20 Section 4.2 Distribution in Shares. 21 Section 4.3 Elective Distributions in Cash or Shares. 22 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Section 4.7 Redemption. 25 26 Section 4.8 Conversion of Foreign Currency. 26 Section 4.9 Fixing of ADS Record Date. 27 Section 4.10 Voting of Deposited Securities. 27 Section 4.11 Changes Affecting Deposited Securities. 29 30 Section 4.12 Available Information. 30 Section 4.13 Reports. 30 Section 4.14 List of Holders. 31 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Third Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 43 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 44 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE]October 2, 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 Depositary 7 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. 8 Shares 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 11 Section 2.5 Issuance of ADSs. 10 ADSs 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 etc 14 Section 2.9 Lost ADRs, etc. 14 etc 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 15 Section 2.11 Escheatment. 14 Escheatment 15 Section 2.12 Partial Entitlement ADSs. 14 ADSs 15 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 16 Section 2.14 Restricted ADSs. 16 ADSs 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 Information 19 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 20 Section 3.4 Compliance with Information Requests. 19 Requests 21 Section 3.5 Ownership Restrictions. 19 Restrictions 22 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 22 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 Distributions 22 Section 4.2 Distribution in Shares. 21 Shares 23 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 25 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 27 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 28 Section 4.7 Redemption. 25 Redemption 28 Section 4.8 Conversion of Foreign Currency. 26 Currency 29 Section 4.9 Fixing of ADS Record Date. 27 Date 30 Section 4.10 Voting of Deposited Securities. 27 Securities 30 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 32 Section 4.12 Available Information. 30 Information 33 Section 4.13 Reports. 30 Reports 33 Section 4.14 List of Holders. 31 Holders 34 Section 4.15 Taxation. 31 Taxation 34 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 35 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Rxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 36 Section 5.3 Standard of Care. 33 Care 37 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 38 Section 5.5 The Custodian. 35 Custodian 38 Section 5.6 Notices and Reports. 35 Reports 39 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 etc 40 Section 5.8 Indemnification. 37 Indemnification 41 Section 5.9 ADS Fees and Charges. 38 Charges 41 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 Owners 43 ARTICLE VI AMENDMENT AND TERMINATION 40 43 Section 6.1 Amendment/Supplement. 40 Supplement 43 Section 6.2 Termination. 41 Termination 44 ARTICLE VII MISCELLANEOUS 42 45 Section 7.1 Counterparts. 42 Counterparts 45 Section 7.2 No Third-Third Party Beneficiaries. 42 /Acknowledgments 45 Section 7.3 Severability. 42 Severability 46 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 46 Section 7.5 Notices. 43 Notices 46 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 47 Section 7.7 Assignment. 45 Assignment 49 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 Laws 49 Section 7.9 England English and Wales Welsh Law References. 45 References 49 Section 7.10 Titles and References. 46 References 49 Section 7.11 Amendment and Restatement 50 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 AMENDED AND RESTATED DEPOSIT AGREEMENT AMENDED AND RESTATED DEPOSIT AGREEMENT, dated as of [DATE]___________, 20172019, by and among (i) NuCana plcTXXX & LXXX PLC, a public limited company incorporated organized under the laws of England and Wales Wales, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. 6 Depositary 7 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. 8 Shares 9 Section 2.4 Registration and Safekeeping of Deposited Securities. Securities 10 Section 2.5 Issuance of ADSs. 10 ADSs 11 Section 2.6 Transfer, Combination and Split-up of ADRs. ADRs 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. etc 13 Section 2.9 Lost ADRs, etc. etc 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. Records 14 Section 2.11 Escheatment. Escheatment 14 Section 2.12 Partial Entitlement ADSs. 14 ADSs 15 Section 2.13 Certificated/Uncertificated ADSs. ADSs 15 Section 2.14 Restricted ADSs. 16 ADSs 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. Information 18 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 19 Section 3.3 Representations and Warranties on Deposit of Shares. Shares 19 Section 3.4 Compliance with Information Requests. 19 Requests 20 Section 3.5 Ownership Restrictions. 19 Restrictions 20 Section 3.6 Reporting Obligations and Regulatory Approvals. Approvals 20 ARTICLE IV THE DEPOSITED SECURITIES 20 21 Section 4.1 Cash Distributions. 20 Distributions 21 Section 4.2 Distribution in Shares. 21 Shares 22 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 23 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 25 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 26 Section 4.7 Redemption. 25 Redemption 27 Section 4.8 Conversion of Foreign Currency. 26 Currency 27 Section 4.9 Fixing of ADS Record Date. 27 Date 28 Section 4.10 Voting of Deposited Securities. 27 Securities 29 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 31 Section 4.12 Available Information. 30 Information 31 Section 4.13 Reports. 30 Reports 32 Section 4.14 List of Holders. 31 Holders 32 Section 4.15 Taxation. 31 Taxation 32 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 33 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Rxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 34 Section 5.3 Standard of Care. 33 Care 34 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 35 Section 5.5 The Custodian. 35 Custodian 36 Section 5.6 Notices and Reports. 35 Reports 37 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 etc 37 Section 5.8 Indemnification. 37 Indemnification 38 Section 5.9 ADS Fees and Charges. 38 Charges 39 Section 5.10 Pre-Release Transactions. 39 Transactions 40 Section 5.11 Restricted Securities Owners. 40 Owners 41 ARTICLE VI AMENDMENT AND TERMINATION 40 41 Section 6.1 Amendment/Supplement. 40 Supplement 41 Section 6.2 Termination. 41 Termination 42 ARTICLE VII MISCELLANEOUS 42 44 Section 7.1 Counterparts. 42 Counterparts 44 Section 7.2 No Third-Third Party Beneficiaries. 42 Beneficiaries 44 Section 7.3 Severability. 42 Severability 44 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 44 Section 7.5 Notices. 43 Notices 44 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 45 Section 7.7 Assignment. 45 Assignment 47 Section 7.8 Compliance with U.S. Securities Laws. 45 Laws 47 Section 7.9 England and Wales Argentine Law References. 45 References 47 Section 7.10 Titles and References. 46 References 47 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE]___________, 2017, by and among (i) NuCana plcLOMA NEGRA COMPAÑÍA INDUSTRIAL ARGENTINA SOCIEDAD ANÓNIMA, a public limited company incorporated organized under the laws of England and Wales Argentina, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. Depositary 6 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. Shares 8 Section 2.4 Registration and Safekeeping of Deposited Securities. Securities 10 Section 2.5 Issuance of ADSs. ADSs 10 Section 2.6 Transfer, Combination and Split-up of ADRs. ADRs 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 Section 2.9 Lost ADRs, etc. 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. Records 14 Section 2.11 Escheatment. Escheatment 14 Section 2.12 Partial Entitlement ADSs. ADSs 14 Section 2.13 Certificated/Uncertificated ADSs. ADSs 15 Section 2.14 Restricted ADSs. ADSs 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. Information 18 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 19 Section 3.3 Representations and Warranties on Deposit of Shares. Shares 19 Section 3.4 Compliance with Information Requests. 19 Requests 20 Section 3.5 Ownership Restrictions. 19 Restrictions 20 Section 3.6 Reporting Obligations and Regulatory Approvals. Approvals 20 ARTICLE IV THE DEPOSITED SECURITIES 20 21 Section 4.1 Cash Distributions. 20 Distributions 21 Section 4.2 Distribution in Shares. 21 Shares 22 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 23 Section 4.4 Distribution of Rights to Purchase Additional ADSs. ADSs 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 25 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 26 Section 4.7 Redemption. 25 Redemption 26 Section 4.8 Conversion of Foreign Currency. 26 Currency 27 Section 4.9 Fixing of ADS Record Date. 27 Date 28 Section 4.10 Voting of Deposited Securities. 27 Securities 28 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 31 Section 4.12 Available Information. 30 Information 32 Section 4.13 Reports. 30 Reports 32 Section 4.14 List of Holders. 31 Holders 32 Section 4.15 Taxation. 31 Taxation 32 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 33 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Xxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 34 Section 5.3 Standard of Care. 33 Care 35 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 36 Section 5.5 The Custodian. 35 Custodian 36 Section 5.6 Notices and Reports. 35 Reports 37 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 etc 38 Section 5.8 Indemnification. 37 Indemnification 39 Section 5.9 ADS Fees and Charges. 38 Charges 40 Section 5.10 Pre-Release Transactions. 39 Transactions 41 Section 5.11 Restricted Securities Owners. 40 Owners 42 ARTICLE VI AMENDMENT AND TERMINATION 40 42 Section 6.1 Amendment/Supplement. 40 Supplement 42 Section 6.2 Termination. 41 Termination 43 ARTICLE VII MISCELLANEOUS 42 44 Section 7.1 Counterparts. 42 Counterparts 44 Section 7.2 No Third-Party Beneficiaries. 42 Beneficiaries 44 Section 7.3 Severability. 42 Severability 44 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 44 Section 7.5 Notices. 43 Notices 45 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 46 Section 7.7 Assignment. 45 Assignment 47 Section 7.8 Compliance with U.S. Securities Laws. 45 Laws 47 Section 7.9 England and Wales Argentine Law References. 45 References 48 Section 7.10 Relationship between the Company and Holders and Beneficial Owners 48 Section 7.11 Titles and References. 46 References 48 EXHIBITS Form of ADR. ADR A-1 Fee Schedule. Schedule B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 20172018, by and among (i) NuCana plcCENTRAL PUERTO S.A., a public limited company incorporated organized under the laws of England and Wales Argentina, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. 6 Section 2.2 Form and Transferability of ADSs. 7 6 Section 2.3 Deposit of Shares. 8 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 9 Section 2.5 Issuance of ADSs. 10 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 10 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 12 Section 2.9 Lost ADRs, etc. 14 13 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 13 Section 2.11 Escheatment. 14 Section 2.12 Partial Entitlement ADSs. 14 Section 2.13 Certificated/Uncertificated ADSs. 15 14 Section 2.14 Restricted ADSs. 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 17 Section 3.1 Proofs, Certificates and Other Information. 18 17 Section 3.2 Liability for Taxes and Other Charges. 18 Section 3.3 Representations and Warranties on Deposit of Shares. 19 18 Section 3.4 Compliance with Information Requests. 19 Section 3.5 Ownership Restrictions. 19 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 19 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. 20 Section 4.2 Distribution in Shares. 21 Section 4.3 Elective Distributions in Cash or Shares. 22 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 22 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Section 4.7 Redemption. 25 Section 4.8 Conversion of Foreign Currency. 26 Section 4.9 Fixing of ADS Record Date. 27 Section 4.10 Voting of Deposited Securities. 27 Section 4.11 Changes Affecting Deposited Securities. 29 Section 4.12 Available Information. 30 Section 4.13 Reports. 30 Section 4.14 List of Holders. 31 30 Section 4.15 Taxation. 31 30 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 31 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 31 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 34 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 37 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 39 ARTICLE VI AMENDMENT AND TERMINATION 40 39 Section 6.1 Amendment/Supplement. 40 39 Section 6.2 Termination. 41 40 ARTICLE VII MISCELLANEOUS 42 41 Section 7.1 Counterparts. 42 41 Section 7.2 No Third-Third Party Beneficiaries. 42 41 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 42 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 44 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 44 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 45 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE]April 23, 20172019, by and among (i) NuCana Mereo BioPharma Group plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 Depositary 7 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. 8 Shares 9 Section 2.4 Registration and Safekeeping of Deposited Securities. Securities 10 Section 2.5 Issuance of ADSs. 10 ADSs 11 Section 2.6 Transfer, Combination and Split-up of ADRs. ADRs 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 etc 14 Section 2.9 Lost ADRs, etc. 14 etc 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 15 Section 2.11 Escheatment. 14 Escheatment 15 Section 2.12 Partial Entitlement ADSs. 14 ADSs 16 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 16 Section 2.14 Restricted ADSs. 16 ADSs 18 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 Information 19 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 20 Section 3.4 Compliance with Information Requests. 19 Requests 21 Section 3.5 Ownership Restrictions. 19 Restrictions 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 21 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 Distributions 22 Section 4.2 Distribution in Shares. 21 Shares 22 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 23 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 27 Section 4.7 Redemption. 25 Redemption 27 Section 4.8 Conversion of Foreign Currency. 26 Currency 27 Section 4.9 Fixing of ADS Record Date. 27 Date 28 Section 4.10 Voting of Deposited Securities. 27 Securities 28 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 30 Section 4.12 Available Information. 30 Information 31 Section 4.13 Reports. 30 Reports 31 Section 4.14 List of Holders. Holders 31 Section 4.15 Taxation. Taxation 31 Section 4.16 Limitation of Rights 32 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Rxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 33 Section 5.3 Standard of Care. 33 Care 34 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 35 Section 5.5 The Custodian. Custodian 35 Section 5.6 Notices and Reports. 35 Reports 36 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 etc 37 Section 5.8 Indemnification. 37 Indemnification 38 Section 5.9 ADS Fees and Charges. 38 Charges 39 Section 5.10 Pre-Release Transactions. 39 Transactions 40 Section 5.11 Restricted Securities Owners. 40 Owners 41 ARTICLE VI AMENDMENT AND TERMINATION 40 41 Section 6.1 Amendment/Supplement. 40 Supplement 41 Section 6.2 Termination. 41 Termination 42 ARTICLE VII MISCELLANEOUS 42 43 Section 7.1 Counterparts. 42 Counterparts 43 Section 7.2 No Third-Third Party Beneficiaries. 42 Beneficiaries 43 Section 7.3 Severability. 42 Severability 43 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 44 Section 7.5 Notices. 43 Notices 44 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 45 Section 7.7 Assignment. 45 Assignment 46 Section 7.8 Compliance with U.S. Securities Laws. 45 Laws 46 Section 7.9 England Relationship between the Company and Wales Law References. 45 Holders and Beneficial Owners 46 Section 7.10 German Law References 47 Section 7.11 Titles and References. 46 References 47 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 20172014, by and among (i) NuCana plcInnocoll AG, a public limited company incorporated organized under the laws of England and Wales the Federal Republic of Germany, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 7 Section 2.2 Form and Transferability of ADSs. 7 8 Section 2.3 Deposit of Shares. 8 10 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 11 Section 2.5 Issuance of ADSs. 10 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 14 Section 2.9 Lost ADRs, etc. 14 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 15 Section 2.11 Escheatment. 14 15 Section 2.12 Partial Entitlement ADSs. 14 15 Section 2.13 Certificated/Uncertificated ADSs. 15 16 Section 2.14 Restricted ADSs. 16 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 19 Section 3.2 Liability for Taxes and Other Charges. 18 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 20 Section 3.4 Compliance with Information Requests. 19 21 Section 3.5 Ownership Restrictions. 19 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 22 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 22 Section 4.2 Distribution in Shares. 21 23 Section 4.3 Elective Distributions in Cash or Shares. 22 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 27 Section 4.7 Redemption. 25 27 Section 4.8 Conversion of Foreign Currency. 26 28 Section 4.9 Fixing of ADS Record Date. 27 29 Section 4.10 Voting of Deposited Securities. 27 29 Section 4.11 Changes Affecting Deposited Securities. 29 32 Section 4.12 Available Information. 30 33 Section 4.13 Reports. 30 33 Section 4.14 List of Holders. 31 34 Section 4.15 Taxation. 31 34 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 36 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 36 Section 5.2 Exoneration. 32 36 Section 5.3 Standard of Care. 33 37 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 38 Section 5.5 The Custodian. 35 39 Section 5.6 Notices and Reports. 35 40 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 40 Section 5.8 Indemnification. 37 41 Section 5.9 ADS Fees and Charges. 38 42 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 43 ARTICLE VI AMENDMENT AND TERMINATION 40 44 Section 6.1 Amendment/Supplement. 40 44 Section 6.2 Termination. 41 44 ARTICLE VII MISCELLANEOUS 42 46 Section 7.1 Counterparts. 42 46 Section 7.2 No Third-Third Party Beneficiaries/Acknowledgments. 42 46 Section 7.3 Severability. 42 47 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 47 Section 7.5 Notices. 43 47 Section 7.6 Governing Law and Jurisdiction. 43 48 Section 7.7 Assignment. 45 50 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 50 Section 7.9 England and Wales French Law References. 45 50 Section 7.10 Titles and References. 46 50 Section 7.11 Amendment and Restatement. 51 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 AMENDED AND RESTATED DEPOSIT AGREEMENT AMENDED AND RESTATED DEPOSIT AGREEMENT, dated as of [DATE]___________, 201720__, by and among (i) NuCana plcACCOR S.A., a public limited company incorporated organized under the laws of England and Wales France, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 Depositary 7 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. 8 Shares 9 Section 2.4 Registration and Safekeeping of Deposited Securities. Securities 10 Section 2.5 Issuance of ADSs. 10 ADSs 11 Section 2.6 Transfer, Combination and Split-up of ADRs. ADRs 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. etc 13 Section 2.9 Lost ADRs, etc. etc 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 15 Section 2.11 Escheatment. 14 Escheatment 15 Section 2.12 Partial Entitlement ADSs. 14 ADSs 15 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 16 Section 2.14 Restricted ADSs. 16 ADSs 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. Information 18 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 19 Section 3.3 Representations and Warranties on Deposit of Shares. Shares 19 Section 3.4 Compliance with Information Requests. 19 Requests 20 Section 3.5 Ownership Restrictions. 19 Restrictions 20 Section 3.6 Reporting Obligations and Regulatory Approvals. Approvals 20 ARTICLE IV THE DEPOSITED SECURITIES 20 21 Section 4.1 Cash Distributions. 20 Distributions 21 Section 4.2 Distribution in Shares. 21 Shares 22 Section 4.3 Elective Distributions in Cash or Shares. Shares 22 Section 4.4 Distribution of Rights to Purchase Additional ADSs. ADSs 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 25 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Redemption 26 Section 4.7 Redemption. 25 Section 4.8 Conversion of Foreign Currency. Currency 26 Section 4.9 4.8 Fixing of ADS Record Date. Date 27 Section 4.9 Voting of Deposited Securities 27 Section 4.10 Voting of Deposited Securities. 27 Section 4.11 Changes Affecting Deposited Securities. Securities 29 Section 4.11 Available Information 30 Section 4.12 Available Information. Reports 30 Section 4.13 Reports. List of Holders 30 Section 4.14 List of Holders. 31 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).Taxation 30

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. Depositary 6 Section 2.2 Form and Transferability of ADSs. 7 ADSs 6 Section 2.3 Deposit of Shares. Shares 8 Section 2.4 Registration and Safekeeping of Deposited Securities. Securities 10 Section 2.5 Issuance of ADSs. ADSs 10 Section 2.6 Transfer, Combination and Split-up of ADRs. ADRs 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. Securities 11 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. etc 13 Section 2.9 Lost ADRs, etc. 14 etc 13 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. Records 14 Section 2.11 Escheatment. Escheatment 14 Section 2.12 Partial Entitlement ADSs. ADSs 14 Section 2.13 Certificated/Uncertificated ADSs. ADSs 15 Section 2.14 Restricted ADSs. ADSs 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. Information 18 Section 3.2 Liability for Taxes and Other Charges. Charges 18 Section 3.3 Representations and Warranties on Deposit of Shares. Shares 19 Section 3.4 Compliance with Information Requests. Requests 19 Section 3.5 Ownership Restrictions. 19 Restrictions 20 Section 3.6 Reporting Obligations and Regulatory Approvals. Approvals 20 ARTICLE IV THE DEPOSITED SECURITIES 20 21 Section 4.1 Cash Distributions. 20 Distributions 21 Section 4.2 Distribution in Shares. 21 Shares 22 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 23 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 25 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 26 Section 4.7 Redemption. 25 Redemption 26 Section 4.8 Conversion of Foreign Currency. 26 Currency 27 Section 4.9 Fixing of ADS Record Date. 27 Date 28 Section 4.10 Voting of Deposited Securities. 27 Securities 28 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 30 Section 4.12 Available Information. 30 Information 31 Section 4.13 Reports. 30 Reports 31 Section 4.14 List of Holders. Holders 31 Section 4.15 Taxation. Taxation 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 33 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Xxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 33 Section 5.3 Standard of Care. 33 Care 34 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 35 Section 5.5 The Custodian. 35 Custodian 36 Section 5.6 Notices and Reports. 35 Reports 36 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 etc 37 Section 5.8 Indemnification. 37 Indemnification 38 Section 5.9 ADS Fees and Charges. 38 Charges 39 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. Owners 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. Supplement 40 Section 6.2 Termination. Termination 41 ARTICLE VII MISCELLANEOUS 42 43 Section 7.1 Counterparts. 42 Counterparts 43 Section 7.2 No Third-Third Party Beneficiaries. 42 /Acknowledgments 43 Section 7.3 Severability. 42 Severability 43 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 44 Section 7.5 Notices. 43 Notices 44 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 45 Section 7.7 Assignment. 45 Assignment 46 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 Laws 46 Section 7.9 England and Wales English Law References. 45 References 47 Section 7.10 Titles and References. 46 References 47 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE]February 9, 20172021, by and among (i) NuCana Immunocore Holdings plc, a public limited company incorporated under the laws of England and Wales Wales, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. 6 Section 2.2 Form and Transferability of ADSs. 7 Section 2.3 Deposit of Shares. 8 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Section 2.5 Issuance of ADSs. 10 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 10 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 Section 2.9 Lost ADRs, etc. 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Section 2.11 Escheatment. 14 Section 2.12 Partial Entitlement ADSs. 14 Section 2.13 Certificated/Uncertificated ADSs. 15 Section 2.14 Restricted ADSs. 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. 18 Section 3.2 Liability for Taxes and Other Charges. 18 19 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Section 3.4 Compliance with Information Requests. 19 Section 3.5 Ownership Restrictions. 19 20 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 ARTICLE IV THE DEPOSITED SECURITIES 20 21 Section 4.1 Cash Distributions. 20 21 Section 4.2 Distribution in Shares. 21 Section 4.3 Elective Distributions in Cash or Shares. 22 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Section 4.7 Redemption. 25 Section 4.8 Conversion of Foreign Currency. 26 Section 4.9 Fixing of ADS Record Date. 27 Section 4.10 Voting of Deposited Securities. 27 Section 4.11 Changes Affecting Deposited Securities. 29 Section 4.12 Available Information. 30 29 Section 4.13 Reports. 30 Section 4.14 List of Holders. 31 30 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).30

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. Depositary 6 Section 2.2 Form and Transferability of ADSs. 7 6 Section 2.3 Deposit of Shares. Shares 8 Section 2.4 Registration and Safekeeping of Deposited Securities. Securities 10 Section 2.5 Issuance of ADSs. ADSs 10 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 Section 2.9 Lost ADRs, etc. etc 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. Records 14 Section 2.11 Escheatment. Escheatment 14 Section 2.12 Partial Entitlement ADSs. ADSs 14 Section 2.13 Certificated/Uncertificated ADSs. ADSs 15 Section 2.14 Restricted ADSs. ADSs 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs ADSS 18 Section 3.1 Proofs, Certificates and Other Information. Information 18 Section 3.2 Liability for Taxes and Other Charges. Charges 18 Section 3.3 Representations and Warranties on Deposit of Shares. Shares 19 Section 3.4 Compliance with Information Requests. Requests 19 Section 3.5 Ownership Restrictions. 19 Restrictions 20 Section 3.6 Reporting Obligations and Regulatory Approvals. Approvals 20 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. Distributions 20 Section 4.2 Distribution in Shares. Shares 21 Section 4.3 Elective Distributions in Cash or Shares. Shares 22 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. Form 25 Section 4.7 Redemption. 25 Redemption 26 Section 4.8 Conversion of Foreign Currency. Currency 26 Section 4.9 Fixing of ADS Record Date. Date 27 Section 4.10 Voting of Deposited Securities. Securities 27 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 31 Section 4.12 Available Information. 30 Information 32 Section 4.13 Reports. 30 Reports 32 Section 4.14 List of Holders. 31 Holders 32 Section 4.15 Taxation. 31 Taxation 32 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 33 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).Rxxxxxxxx 00

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 7 Section 2.2 Form and Transferability of ADSs. 7 Section 2.3 Deposit of Shares. 8 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 11 Section 2.5 Issuance of ADSs. 10 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 14 Section 2.9 Lost ADRs, etc. 14 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 15 Section 2.11 Escheatment. 14 15 Section 2.12 Partial Entitlement ADSs. 14 15 Section 2.13 Certificated/Uncertificated ADSs. 15 16 Section 2.14 Restricted ADSs. 16 18 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 19 Section 3.2 Liability for Taxes and Other Charges. 18 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 20 Section 3.4 Compliance with Information Requests. 19 21 Section 3.5 Ownership Restrictions. 19 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 21 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 22 Section 4.2 Distribution in Shares. 21 23 Section 4.3 Elective Distributions in Cash or Shares. 22 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 27 Section 4.7 Redemption. 25 27 Section 4.8 Conversion of Foreign Currency. 26 28 Section 4.9 Fixing of ADS Record Date. 27 29 Section 4.10 Voting of Deposited Securities. 27 29 Section 4.11 Changes Affecting Deposited Securities. 29 31 Section 4.12 Available Information. 30 32 Section 4.13 Reports. 30 32 Section 4.14 List of Holders. 31 33 Section 4.15 Taxation. 31 33 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 34 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 34 Section 5.2 Exoneration. 32 35 Section 5.3 Standard of Care. 33 35 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 36 Section 5.5 The Custodian. 35 37 Section 5.6 Notices and Reports. 35 38 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 38 Section 5.8 Indemnification. 37 39 Section 5.9 ADS Fees and Charges. 38 40 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 42 ARTICLE VI AMENDMENT AND TERMINATION 40 42 Section 6.1 Amendment/Supplement. 40 42 Section 6.2 Termination. 41 43 ARTICLE VII MISCELLANEOUS 42 44 Section 7.1 Counterparts. 42 44 Section 7.2 No Third-Third Party Beneficiaries/Acknowledgments. 42 44 Section 7.3 Severability. 42 45 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 45 Section 7.5 Notices. 43 45 Section 7.6 Governing Law and Jurisdiction. 43 46 Section 7.7 Assignment. 45 48 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 48 Section 7.9 England and Wales The Cayman Islands Law References. 45 48 Section 7.10 Titles and References. 46 48 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE●], 20172020, by and among (i) NuCana plcPHOENIX TREE HOLDINGS LIMITED, a public limited an exempted company incorporated under the laws of England and Wales the Cayman Islands, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 9 Section 2.1 Appointment of Depositary. 6 Depositary 9 Section 2.2 Form and Transferability of ADSs. 7 ADSs 10 Section 2.3 Deposit of Shares. 8 with Custodian 11 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 13 Section 2.5 Issuance of ADSs. 10 ADSs 13 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 13 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 15 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 16 Section 2.9 Lost ADRs, etc. 14 17 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 17 Section 2.11 Escheatment. 14 Escheatment 17 Section 2.12 Partial Entitlement ADSs. 14 ADSs 17 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 18 Section 2.14 Restricted ADSs. 16 ADSs 19 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 21 Section 3.1 Proofs, Certificates and Other Information. 18 Information 21 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 21 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 22 Section 3.4 Compliance with Information Requests. 19 Requests and Applicable Law 22 Section 3.5 Ownership Restrictions. 19 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Restrictions 23 ARTICLE IV THE DEPOSITED SECURITIES 20 24 Section 4.1 Cash Distributions. 20 Distributions 24 Section 4.2 Distribution in Shares. 21 Shares 24 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 25 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 25 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 27 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 28 Section 4.7 Redemption. 25 Redemption 28 Section 4.8 Conversion of Foreign Currency. 26 Currency 29 Section 4.9 Fixing of ADS Record Date. 27 Date 30 Section 4.10 Voting of Deposited Securities. 27 Securities 30 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 32 Section 4.12 Available Information. 30 Information 33 Section 4.13 Reports. 30 Reports 33 Section 4.14 List of Holders. 31 Holders 33 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).Taxation 33

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT RECEIPTS;DEPOSIT OF SHARES; EXECUTION AND DELIVERYANDDELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. Depositary 6 Section 2.2 Form and Transferability of ADSs. 7 ADSs 6 Section 2.3 Deposit of Shares. Shares 8 Section 2.4 Registration and Safekeeping of Deposited Securities. Securities 10 Section 2.5 Issuance of ADSs. ADSs 10 Section 2.6 Transfer, Combination and Split-up of ADRs. ADRs 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. etc 13 Section 2.9 Lost ADRs, etc. etc 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. Records 14 Section 2.11 Escheatment. Escheatment 14 Section 2.12 Partial Entitlement ADSs. ADSs 14 Section 2.13 Certificated/Uncertificated ADSs. ADSs 15 Section 2.14 Restricted ADSs. ADSs 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. Information 18 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 19 Section 3.3 Representations and Warranties on Deposit of Shares. Shares 19 Section 3.4 Compliance with Information Requests. Requests 19 Section 3.5 Ownership Restrictions. 19 Restrictions 20 Section 3.6 Reporting Obligations and Regulatory Approvals. Approvals 20 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. Distributions 20 Section 4.2 Distribution in Shares. Shares 21 Section 4.3 Elective Distributions in Cash or Shares. Shares 22 Section 4.4 Distribution of Rights to Purchase Additional ADSs. ADSs 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 25 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 26 Section 4.7 Redemption. 25 Redemption 26 Section 4.8 Conversion of Foreign Currency. 26 Currency 27 Section 4.9 Fixing of ADS Record Date. Date 27 Section 4.10 Voting of Deposited Securities. 27 Securities 28 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 30 Section 4.12 Available Information. 30 Information 31 Section 4.13 Reports. 30 Reports 31 Section 4.14 List of Holders. Holders 31 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).Taxation 31

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 7 Section 2.2 Form and Transferability of ADSs. 7 Section 2.3 Deposit of Shares. 8 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 11 Section 2.5 Issuance of ADSs. 10 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 14 Section 2.9 Lost ADRs, etc. 14 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 15 Section 2.11 Escheatment. 14 15 Section 2.12 Partial Entitlement ADSs. 14 15 Section 2.13 Certificated/Uncertificated ADSs. 15 16 Section 2.14 Restricted ADSs. 16 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 19 Section 3.2 Liability for Taxes and Other Charges. 18 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 20 Section 3.4 Compliance with Information Requests. 19 20 Section 3.5 Ownership Restrictions. 19 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 21 ARTICLE IV THE DEPOSITED SECURITIES 20 21 Section 4.1 Cash Distributions. 20 21 Section 4.2 Distribution in Shares. 21 22 Section 4.3 Elective Distributions in Cash or Shares. 22 23 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 27 Section 4.7 Redemption. 25 27 Section 4.8 Conversion of Foreign Currency. 26 28 Section 4.9 Fixing of ADS Record Date. 27 28 Section 4.10 Voting of Deposited Securities. 27 29 Section 4.11 Changes Affecting Deposited Securities. 29 31 Section 4.12 Available Information. 30 32 Section 4.13 Reports. 30 32 Section 4.14 List of Holders. 31 32 Section 4.15 Taxation. 31 32 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 33 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 33 Section 5.2 Exoneration. 32 34 Section 5.3 Standard of Care. 33 34 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 35 Section 5.5 The Custodian. 35 36 Section 5.6 Notices and Reports. 35 37 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 38 Section 5.8 Indemnification. 37 38 Section 5.9 ADS Fees and Charges. 38 39 Section 5.10 Pre-Release Transactions. 39 41 Section 5.11 Restricted Securities Owners. 40 41 ARTICLE VI AMENDMENT AND TERMINATION 40 41 Section 6.1 Amendment/Supplement. 40 41 Section 6.2 Termination. 41 42 ARTICLE VII MISCELLANEOUS 42 43 Section 7.1 Counterparts. 42 43 Section 7.2 No Third-Third Party Beneficiaries. 42 44 Section 7.3 Severability. 42 44 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 44 Section 7.5 Notices. 43 44 Section 7.6 Governing Law and Jurisdiction. 43 45 Section 7.7 Assignment. 45 47 Section 7.8 Compliance with U.S. Securities Laws. 45 47 Section 7.9 England and Wales Cayman Islands Law References. 45 47 Section 7.10 Titles and References. 46 48 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plcPPDAI GROUP INC., a public an exempted company with limited company liability incorporated under the laws of England and Wales the Cayman Islands, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 8 Section 2.1 Appointment of Depositary. 6 Depositary 8 Section 2.2 Form and Transferability of ADSs. 7 ADSs 8 Section 2.3 Deposit of Shares. 8 Shares 10 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 12 Section 2.5 Issuance of ADSs. 10 ADSs 12 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 13 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 14 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 etc 15 Section 2.9 Lost ADRs, etc. 14 etc 16 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 16 Section 2.11 Escheatment. 14 Escheatment 16 Section 2.12 Partial Entitlement ADSs. 14 ADSs 16 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 17 Section 2.14 Restricted ADSs. 16 ADSs 18 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 20 Section 3.1 Proofs, Certificates and Other Information. 18 Information 20 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 21 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 21 Section 3.4 Compliance with Information Requests. 19 Requests 21 Section 3.5 Ownership Restrictions. 19 Restrictions 22 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 23 ARTICLE IV THE DEPOSITED SECURITIES 20 23 Section 4.1 Cash Distributions. 20 Distributions 23 Section 4.2 Distribution in Shares. 21 Shares 24 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 25 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 26 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 28 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 29 Section 4.7 Redemption. 25 Redemption 29 Section 4.8 Conversion of Foreign Currency. 26 Currency 30 Section 4.9 Fixing of ADS Record Date. 27 Date 30 Section 4.10 Voting of Deposited Securities. 27 Securities 31 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 33 Section 4.12 Available Information. 30 Information 34 Section 4.13 Reports. 30 Reports 34 Section 4.14 List of Holders. 31 Holders 34 Section 4.15 Taxation. 31 Taxation 34 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 36 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Rxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 36 Section 5.3 Standard of Care. 33 Care 37 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 38 Section 5.5 The Custodian. 35 Custodian 39 Section 5.6 Notices and Reports. 35 Reports 39 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 etc 40 Section 5.8 Indemnification. 37 Indemnification 41 Section 5.9 ADS Fees and Charges. 38 Charges 42 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 Owners 43 ARTICLE VI AMENDMENT AND TERMINATION 40 43 Section 6.1 Amendment/Supplement. 40 Supplement 43 Section 6.2 Termination. 41 Termination 44 ARTICLE VII MISCELLANEOUS 42 46 Section 7.1 Counterparts. 42 Counterparts 46 Section 7.2 No Third-Third Party Beneficiaries. 42 /Acknowledgments 46 Section 7.3 Severability. 42 Severability 46 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 46 Section 7.5 Notices. 43 Notices 47 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 47 Section 7.7 Assignment. 45 Assignment 49 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 Laws 49 Section 7.9 England and Wales English Law References. 45 References 50 Section 7.10 Titles and References. 46 References 50 Section 7.11 Amendment and Restatement 51 EXHIBITS Form of ADR. ADR A-1 Fee Schedule. Schedule B-1 AMENDED AND RESTATED DEPOSIT AGREEMENT AMENDED AND RESTATED DEPOSIT AGREEMENT, dated as of [DATE·], 20172020, by and among (i) NuCana ANGLE plc, a public limited company incorporated under the laws of England and Wales Wales, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and its successors, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 Depositary 7 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. 8 Shares 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 11 Section 2.5 Issuance of ADSs. 10 ADSs 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 14 Section 2.9 Lost ADRs, etc. 14 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 15 Section 2.11 Escheatment. 14 Escheatment 15 Section 2.12 Partial Entitlement ADSs. 14 ADSs 16 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 17 Section 2.14 Restricted ADSs. 16 ADSs 18 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 Information 19 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 20 Section 3.4 Compliance with Information Requests. 19 Requests 21 Section 3.5 Ownership Restrictions. 19 Restrictions 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 21 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 Distributions 22 Section 4.2 Distribution in Shares. 21 Shares 23 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 27 Section 4.7 Redemption. 25 Redemption 27 Section 4.8 Conversion of Foreign Currency. 26 Currency 28 Section 4.9 Fixing of ADS Record Date. 27 Date 29 Section 4.10 Voting of Deposited Securities. 27 Securities 29 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 32 Section 4.12 Available Information. 30 Information 32 Section 4.13 Reports. 30 Reports 32 Section 4.14 List of Holders. 31 Holders 33 Section 4.15 Taxation. 31 Taxation 33 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 34 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Xxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 35 Section 5.3 Standard of Care. 33 Care 35 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 36 Section 5.5 The Custodian. 35 Custodian 37 Section 5.6 Notices and Reports. 35 Reports 38 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 39 Section 5.8 Indemnification. 37 Indemnification 39 Section 5.9 ADS Fees and Charges. 38 Charges 40 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 Owners 42 ARTICLE VI AMENDMENT AND TERMINATION 40 42 Section 6.1 Amendment/Supplement. 40 Supplement 42 Section 6.2 Termination. 41 Termination 43 ARTICLE VII MISCELLANEOUS 42 44 Section 7.1 Counterparts. 42 Counterparts 44 Section 7.2 No Third-Party Beneficiaries. 42 /Acknowledgments 44 Section 7.3 Severability. 42 Severability 45 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 45 Section 7.5 Notices. 43 Notices 45 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 46 Section 7.7 Assignment. 45 Assignment 48 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 Laws 48 Section 7.9 England and Wales The Cayman Islands Law References. 45 References 48 Section 7.10 Titles and References. 46 References 48 EXHIBITS Form of ADR. ADR A-1 Fee Schedule. Schedule B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE]January 22, 20172020, by and among (i) NuCana plcI-MAB, a public limited an exempted company incorporated under in the laws of England and Wales Cayman Islands, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 Depositary 7 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. 8 Shares 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 11 Section 2.5 Issuance of ADSs. 10 ADSs 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 etc 14 Section 2.9 Lost ADRs, etc. 14 etc 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 15 Section 2.11 Escheatment. 14 Escheatment 15 Section 2.12 Partial Entitlement ADSs. 14 ADSs 16 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 16 Section 2.14 Restricted ADSs. 16 ADSs 18 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 Information 19 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 20 Section 3.4 Compliance with Information Requests. 19 Requests 21 Section 3.5 Ownership Restrictions. 19 Restrictions 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 21 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 Distributions 22 Section 4.2 Distribution in Shares. 21 Shares 23 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 27 Section 4.7 Redemption. 25 Redemption 27 Section 4.8 Conversion of Foreign Currency. 26 Currency 28 Section 4.9 Fixing of ADS Record Date. 27 Date 29 Section 4.10 Voting of Deposited Securities. 27 Securities 29 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 31 Section 4.12 Available Information. 30 Information 31 Section 4.13 Reports. 30 Reports 32 Section 4.14 List of Holders. 31 Holders 32 Section 4.15 Taxation. 31 Taxation 32 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 33 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Xxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 34 Section 5.3 Standard of Care. 33 Care 34 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 35 Section 5.5 The Custodian. 35 Custodian 36 Section 5.6 Notices and Reports. 35 Reports 37 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 etc 38 Section 5.8 Indemnification. 37 Indemnification 39 Section 5.9 ADS Fees and Charges. 38 Charges 39 Section 5.10 Pre-Release Transactions. 39 Transactions 41 Section 5.11 Restricted Securities Owners. 40 Owners 41 ARTICLE VI AMENDMENT AND TERMINATION 40 41 Section 6.1 Amendment/Supplement. 40 Supplement 41 Section 6.2 Termination. 41 Termination 42 ARTICLE VII MISCELLANEOUS 42 43 Section 7.1 Counterparts. 42 Counterparts 43 Section 7.2 No Third-Third Party Beneficiaries. 42 Beneficiaries 44 Section 7.3 Severability. 42 Severability 44 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 44 Section 7.5 Notices. 43 Notices 44 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 45 Section 7.7 Assignment. 45 Assignment 47 Section 7.8 Compliance with U.S. Securities Laws. 45 Laws 47 Section 7.9 England and Wales German Law References. 45 References 47 Section 7.10 Titles and References. 46 References 47 Section 7.11 Amendment and Restatement 48 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 AMENDED AND RESTATED DEPOSIT AGREEMENT AMENDED AND RESTATED DEPOSIT AGREEMENT, dated as of [DATE]___________, 201720__, by and among (i) NuCana plcE.ON SE, a public limited company incorporated organized under the laws of England and Wales the Federal Republic of Germany, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. 6 Section 2.2 Form and Transferability of ADSs. 7 6 Section 2.3 Deposit of Shares. 8 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 9 Section 2.5 Issuance of ADSs. 10 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 10 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 12 Section 2.9 Lost ADRs, etc. 14 13 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 13 Section 2.11 Escheatment. 14 Section 2.12 Partial Entitlement ADSs. 14 Section 2.13 Certificated/Uncertificated ADSs. 15 Section 2.14 Restricted ADSs. 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. 18 Section 3.2 Liability for Taxes and Other Charges. 18 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Section 3.4 Compliance with Information Requests. 19 Section 3.5 Ownership Restrictions. 19 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. 20 Section 4.2 Distribution in Shares. 21 Section 4.3 Elective Distributions in Cash or Shares. 22 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. [Intentionally Omitted] 25 Section 4.7 Redemption. 25 Section 4.8 Conversion of Foreign Currency. 26 Section 4.9 Fixing of ADS Record Date. 27 Section 4.10 Voting of Deposited Securities. 27 Section 4.11 Changes Affecting Deposited Securities. 29 Section 4.12 Available Information. 30 Section 4.13 Reports. 30 Section 4.14 List of Holders. 31 30 Section 4.15 Taxation. 31 30 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 31 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 31 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 34 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 39 ARTICLE VI AMENDMENT AND TERMINATION 40 39 Section 6.1 Amendment/Supplement. 40 39 Section 6.2 Termination. 41 40 ARTICLE VII MISCELLANEOUS 42 41 Section 7.1 Counterparts. 42 41 Section 7.2 No Third-Third Party Beneficiaries/Acknowledgments. 42 41 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 42 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 Section 7.9 England and Wales Swedish Law References. 45 Section 7.10 Titles and References. 46 45 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE]___________, 20172020, by and among (i) NuCana plcCalliditas Therapeutics AB, a public limited company incorporated organized under the laws of England and Wales the Kingdom of Sweden, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTSRECEIPT; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 5 SECTION 2.1 Appointment of Depositary. 6 Section Depositary 5 SECTION 2.2 Form and Transferability of ADSs. 7 Section Receipts 5 SECTION 2.3 Deposit Deposits 6 SECTION 2.4 Execution and Delivery of Shares. Receipts 8 Section 2.4 Registration and Safekeeping SECTION 2.5 Transfer of Deposited Securities. 10 Section 2.5 Issuance of ADSs. 10 Section 2.6 Transfer, Receipts; Combination and Split-up of ADRs. 11 Section 2.7 Receipts 8 SECTION 2.6 Surrender of ADSs Receipts and Withdrawal of Deposited Securities. 11 Section 2.8 Securities 9 SECTION 2.7 Limitations on Execution and Delivery, Transfer, etc. of ADSsReceipts; Suspension of Delivery, Transfer, etc. 13 Section 2.9 10 SECTION 2.8 Lost ADRsReceipts, etc. 14 Section 2.10 10 SECTION 2.9 Cancellation and Destruction of Surrendered ADRsReceipts; Maintenance of RecordsRecords 11 SECTION 2.10 Pre-Release 11 ARTICLE III. 14 Section 2.11 Escheatment. 14 Section 2.12 Partial Entitlement ADSs. 14 Section 2.13 Certificated/Uncertificated ADSs. 15 Section 2.14 Restricted ADSs. 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section RECEIPTS 12 SECTION 3.1 Proofs, Certificates and Other Information. 18 Section Information 12 SECTION 3.2 Liability for Taxes and Other Charges. 18 Section Charges 12 SECTION 3.3 Representations and Warranties on Deposit of Shares. 19 Section Shares 13 SECTION 3.4 Ownership Restrictions 13 SECTION 3.5 Compliance with Information Requests. 19 Section 3.5 Ownership Restrictions. 19 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Requests 13 ARTICLE IV THE DEPOSITED SECURITIES 20 Section SECURITIES. 15 SECTION 4.1 Cash Distributions. 20 Section Distributions 15 SECTION 4.2 Distribution in Shares. 21 Section Shares 16 SECTION 4.3 Elective Distributions in Cash or Shares. 22 Section Shares 16 SECTION 4.4 Distribution of Rights to Purchase Additional ADSs. 23 Section Shares 17 SECTION 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Section Shares 19 SECTION 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Section 4.7 Redemption. 25 Section 4.8 Conversion of Foreign Currency. 26 Section 4.9 Currency 19 SECTION 4.7 Fixing of ADS Record Date. 27 Section 4.10 Date 20 SECTION 4.8 Voting of Deposited Securities. 27 Section 4.11 Securities 20 SECTION 4.9 Changes Affecting Deposited Securities. 29 Section Securities 22 SECTION 4.10 Available Information 23 SECTION 4.11 Reports 23 SECTION 4.12 Available Information. 30 Section 4.13 Reports. 30 Section 4.14 List of HoldersHolders 23 SECTION 4.13 Taxation; Withholding 23 SECTION 4.14 Affiliates etc. 31 Section 4.15 Taxation. 31 24 ARTICLE V V. THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 24 SECTION 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section Rxxxxxxxx 00 SECTION 5.2 Exoneration. 32 Section Exoneration 25 SECTION 5.3 Standard of Care. 33 Section Care 26 SECTION 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section Depositary 27 SECTION 5.5 The Custodian. 35 Section Custodian 28 SECTION 5.6 Notices and Reports. 35 Section Reports 28 SECTION 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 29 SECTION 5.8 Indemnification. 37 Section Indemnification 30 SECTION 5.9 ADS Fees and Charges. 38 Section Charges of Depositary 31 SECTION 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners/Ownership Restrictions 32 ARTICLE VI. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 32 SECTION 6.1 Amendment/SupplementSupplement 32 SECTION 6.2 Termination 33 ARTICLE VII. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 34 SECTION 7.1 Counterparts. 42 Section Counterparts 34 SECTION 7.2 No Third-Party Beneficiaries. 42 Section Beneficiaries 34 SECTION 7.3 Severability. 42 Section Severability 35 SECTION 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section Effect 35 SECTION 7.5 Notices. 43 Section Notices 35 SECTION 7.6 Governing Law and Jurisdiction. 43 Section Jurisdiction 36 SECTION 7.7 Assignment. 45 Section Assignment 37 SECTION 7.8 Compliance with U.S. Securities Laws. 45 Section Laws 37 SECTION 7.9 England and Wales Law References. 45 Section Titles; References 37 SECTION 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).Agents 38 SECTION 7.11 Exclusivity 38

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. 6 7 Section 2.2 Form and Transferability of ADSs. 7 Section 2.3 Deposit of Shares. 8 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 11 Section 2.5 Issuance of ADSs. 10 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 14 Section 2.9 Lost ADRs, etc. 14 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 15 Section 2.11 Escheatment. 14 15 Section 2.12 Partial Entitlement ADSs. 14 16 Section 2.13 Certificated/Uncertificated ADSs. 15 16 Section 2.14 Restricted ADSs. 16 18 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 19 Section 3.2 Liability for Taxes and Other Charges. 18 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 20 Section 3.4 Compliance with Information Requests. 19 20 Section 3.5 Ownership Restrictions. 19 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 21 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 22 Section 4.2 Distribution in Shares. 21 23 Section 4.3 Elective Distributions in Cash or Shares. 22 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form[Intentionally Omitted]. 25 27 Section 4.7 Redemption. 25 27 Section 4.8 Conversion of Foreign Currency. 26 27 Section 4.9 Fixing of ADS Record Date. 27 28 Section 4.10 Voting of Deposited Securities. 27 29 Section 4.11 Changes Affecting Deposited Securities. 29 31 Section 4.12 Available Information. 30 32 Section 4.13 Reports. 30 32 Section 4.14 List of Holders. 31 32 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).32

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. Depositary 6 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. Shares 8 Section 2.4 Registration and Safekeeping of Deposited Securities. Securities 10 Section 2.5 Issuance of ADSs. ADSs 10 Section 2.6 Transfer, Combination and Split-up of ADRs. ADRs 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. etc 13 Section 2.9 Lost ADRs, etc. etc 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records Section 2.11 Escheatment. Escheatment 14 Section 2.12 Partial Entitlement ADSs. ADSs 14 Section 2.13 Certificated/Uncertificated ADSs. ADSs 15 Section 2.14 Restricted ADSs. ADSs 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. Information 18 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 19 Section 3.3 Representations and Warranties on Deposit of Shares. Shares 19 Section 3.4 Compliance with Information Requests. 19 Requests 20 Section 3.5 Ownership Restrictions. 19 Restrictions 20 Section 3.6 Reporting Obligations and Regulatory Approvals. Approvals 20 ARTICLE IV THE DEPOSITED SECURITIES 20 21 Section 4.1 Cash Distributions. 20 Distributions 21 Section 4.2 Distribution in Shares. 21 Shares 22 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 23 Section 4.4 Distribution of Rights to Purchase Additional ADSs. ADSs 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 25 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 26 Section 4.7 Redemption. 25 Redemption 26 Section 4.8 Conversion of Foreign Currency. 26 Currency 27 Section 4.9 Fixing of ADS Record Date. 27 Date 28 Section 4.10 Voting of Deposited Securities. 27 Securities 28 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 31 Section 4.12 Available Information. 30 Information 32 Section 4.13 Reports. 30 Reports 32 Section 4.14 List of Holders. 31 Holders 32 Section 4.15 Taxation. 31 Taxation 32 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 33 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Rxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 34 Section 5.3 Standard of Care. 33 Care 35 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 36 Section 5.5 The Custodian. 35 Custodian 37 Section 5.6 Notices and Reports. 35 Reports 37 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 etc 38 Section 5.8 Indemnification. 37 Indemnification 39 Section 5.9 ADS Fees and Charges. 38 Charges 40 Section 5.10 Pre-Release Transactions. 39 Transactions 41 Section 5.11 Restricted Securities Owners. 40 Owners 42 ARTICLE VI AMENDMENT AND TERMINATION 40 42 Section 6.1 Amendment/Supplement. 40 Supplement 42 Section 6.2 Termination. 41 Termination 43 ARTICLE VII MISCELLANEOUS 42 44 Section 7.1 Counterparts. 42 Counterparts 44 Section 7.2 No Third-Third Party Beneficiaries. 42 Beneficiaries 44 Section 7.3 Severability. 42 Severability 45 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 45 Section 7.5 Notices. 43 Notices 45 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 46 Section 7.7 Assignment. 45 Assignment 48 Section 7.8 Compliance with U.S. Securities Laws. 45 Laws 48 Section 7.9 England and Wales Argentine Law References. 45 References 48 Section 7.10 Relationship between the Company and Holders and Beneficial Owners 48 Section 7.11 Titles and References. 46 References 48 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE]___________, 20172018, by and among (i) NuCana plcCENTRAL PUERTO S.A., a public limited company incorporated organized under the laws of England and Wales Argentina, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. Depositary 6 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. Shares 8 Section 2.4 Registration and Safekeeping of Deposited Securities. Securities 10 Section 2.5 Issuance of ADSs. ADSs 10 Section 2.6 Transfer, Combination and Split-up of ADRs. ADRs 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. etc 13 Section 2.9 Lost ADRs, etc. etc 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. Records 14 Section 2.11 Escheatment. Escheatment 14 Section 2.12 Partial Entitlement ADSs. ADSs 14 Section 2.13 Certificated/Uncertificated ADSs. ADSs 15 Section 2.14 Restricted ADSs. ADSs 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. Information 18 Section 3.2 Liability for Taxes and Other Charges. Charges 18 Section 3.3 Representations and Warranties on Deposit of Shares. Shares 19 Section 3.4 Compliance with Information Requests. Requests 19 Section 3.5 Ownership Restrictions. Restrictions 19 Section 3.6 Reporting Obligations and Regulatory Approvals. Approvals 20 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. Distributions 20 Section 4.2 Distribution in Shares. Shares 21 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 21 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 22 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. Shares 24 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. [Intentionally Omitted] 25 Section 4.7 Redemption. Redemption 25 Section 4.8 Conversion of Foreign Currency. 26 Currency 25 Section 4.9 Fixing of ADS Record Date. Date 27 Section 4.10 Voting of Deposited Securities. Securities 27 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 28 Section 4.12 Available Information. 30 Information 28 Section 4.13 Reports. 30 Reports 29 Section 4.14 List of Holders. 31 Holders 29 Section 4.15 Taxation. 31 Taxation 29 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 30 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Xxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 30 Section 5.3 Standard of Care. 33 Care 31 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 32 Section 5.5 The Custodian. 35 Custodian 33 Section 5.6 Notices and Reports. 35 Reports 33 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 etc 34 Section 5.8 Indemnification. 37 Indemnification 35 Section 5.9 ADS Fees and Charges. 38 Charges of Depositary 36 Section 5.10 Pre-Release Transactions. 39 Transactions 37 Section 5.11 Restricted Securities Owners. 40 Owners 37 ARTICLE VI AMENDMENT AND TERMINATION 40 38 Section 6.1 Amendment/Supplement. 40 Supplement 38 Section 6.2 Termination. 41 Termination 38 ARTICLE VII MISCELLANEOUS 42 40 Section 7.1 Counterparts. 42 Counterparts 40 Section 7.2 No Third-Party Beneficiaries. 42 Beneficiaries 40 Section 7.3 Severability. 42 Severability 40 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 40 Section 7.5 Notices. 43 Notices 40 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 41 Section 7.7 Assignment. 45 Assignment 43 Section 7.8 Compliance with U.S. Securities Laws. 45 Laws 43 Section 7.9 England and Wales Brazilian Law References. 45 References 43 Section 7.10 Titles and References. 46 References 43 Section 7.11 Amendment and Restatement 44 EXHIBITS Form of ADR. ADR A-1 Fee Schedule. Schedule B-1 EXECUTION VERSION SECOND AMENDED AND RESTATED DEPOSIT AGREEMENT SECOND AMENDED AND RESTATED DEPOSIT AGREEMENT, dated as of [DATE]August 12, 20172009, by and among (i) NuCana plcVotorantim Celulose e Papel S.A., a public limited company incorporated organized under the laws of England and Wales the Federative Republic of Brazil, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 8 Section 2.1 Appointment of Depositary. 6 Depositary 8 Section 2.2 Form and Transferability of ADSs. 7 ADSs 8 Section 2.3 Deposit of Shares. 8 Shares 10 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 12 Section 2.5 Issuance of ADSs. 10 ADSs 12 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 13 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 14 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 etc 15 Section 2.9 Lost ADRs, etc. 14 etc 16 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 16 Section 2.11 Escheatment. 14 Escheatment 16 Section 2.12 Partial Entitlement ADSs. 14 ADSs 17 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 17 Section 2.14 Restricted ADSs. 16 ADSs 19 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 20 Section 3.1 Proofs, Certificates and Other Information. 18 Information 20 Section 3.2 Liability for Taxes and Other Charges. 18 Governmental Charges 21 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 22 Section 3.4 Compliance with Information Requests. 19 Requests 22 Section 3.5 Ownership Restrictions. 19 Restrictions 22 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 23 ARTICLE IV THE DEPOSITED SECURITIES 20 23 Section 4.1 Cash Distributions. 20 Distributions 23 Section 4.2 Distribution in Shares. 21 Shares 24 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 25 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 27 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 28 Section 4.7 Redemption. 25 Redemption 28 Section 4.8 Conversion of Foreign Currency. 26 Currency 29 Section 4.9 Fixing of ADS Record Date. 27 Date 30 Section 4.10 Voting of Deposited Securities. 27 Securities 30 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 33 Section 4.12 Available Information. 30 Information 34 Section 4.13 Reports. 30 Reports 34 Section 4.14 List of Holders. 31 Holders 34 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).Taxation 34

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 7 Section 2.2 Form and Transferability of ADSs. 7 8 Section 2.3 Deposit of Shares. 8 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 11 Section 2.5 Issuance of ADSs. 10 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 14 Section 2.9 Lost ADRs, etc. 14 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 15 Section 2.11 Escheatment. 14 15 Section 2.12 Partial Entitlement ADSs. 14 16 Section 2.13 Certificated/Uncertificated ADSs. 15 16 Section 2.14 Restricted ADSs. 16 18 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 19 Section 3.2 Liability for Taxes and Other Charges. 18 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 20 Section 3.4 Compliance with Information Requests. 19 21 Section 3.5 Ownership Restrictions. 19 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 21 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 22 Section 4.2 Distribution in Shares. 21 23 Section 4.3 Elective Distributions in Cash or Shares. 22 23 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 27 Section 4.7 Redemption. 25 27 Section 4.8 Conversion of Foreign Currency. 26 28 Section 4.9 Fixing of ADS Record Date. 27 29 Section 4.10 Voting of Deposited Securities. 27 29 Section 4.11 Changes Affecting Deposited Securities. 29 31 Section 4.12 Available Information. 30 31 Section 4.13 Reports. 30 32 Section 4.14 List of Holders. 31 32 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).32

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 Depositary 7 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. 8 Shares 9 Section 2.4 Registration and Safekeeping of Deposited Securities. Securities 10 Section 2.5 Issuance of ADSs. 10 ADSs 11 Section 2.6 Transfer, Combination and Split-up of ADRs. ADRs 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 etc 14 Section 2.9 Lost ADRs, etc. 14 etc 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 15 Section 2.11 Escheatment. 14 Escheatment 15 Section 2.12 Partial Entitlement ADSs. 14 ADSs 15 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 16 Section 2.14 Restricted ADSs. 16 ADSs 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 Information 19 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 20 Section 3.4 Compliance with Information Requests. 19 Requests 20 Section 3.5 Ownership Restrictions. 19 Restrictions 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 21 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 Distributions 22 Section 4.2 Distribution in Shares. 21 Shares 23 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 25 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 27 Section 4.7 Redemption. 25 Redemption 28 Section 4.8 Conversion of Foreign Currency. 26 Currency 28 Section 4.9 Fixing of ADS Record Date. 27 Date 29 Section 4.10 Voting of Deposited Securities. 27 Securities 29 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 33 Section 4.12 Available Information. 30 Information 33 Section 4.13 Reports. 30 Reports 33 Section 4.14 List of Holders. 31 Holders 34 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).Taxation 34

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. 6 Section 2.2 Form and Transferability of ADSs. 7 6 Section 2.3 Deposit of Shares. 8 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 9 Section 2.5 Issuance of ADSs. 10 9 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 10 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 12 Section 2.9 Lost ADRs, etc. 14 13 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 13 Section 2.11 Escheatment. 14 13 Section 2.12 Partial Entitlement ADSs. 14 Section 2.13 Certificated/Uncertificated ADSs. 15 Section 2.14 Restricted ADSs. 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 17 Section 3.1 Proofs, Certificates and Other Information. 18 17 Section 3.2 Liability for Taxes and Other Charges. 18 Section 3.3 Representations and Warranties on Deposit of Shares. 19 18 Section 3.4 Compliance with Information Requests. 19 Section 3.5 Ownership Restrictions. 19 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 19 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. 20 Section 4.2 Distribution in Shares. 21 Section 4.3 Elective Distributions in Cash or Shares. 22 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 25 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Section 4.7 Redemption. 25 26 Section 4.8 Conversion of Foreign Currency. 26 Section 4.9 Fixing of ADS Record Date. 27 Section 4.10 Voting of Deposited Securities. 27 Section 4.11 Changes Affecting Deposited Securities. 29 30 Section 4.12 Available Information. 30 Section 4.13 Reports. 30 Section 4.14 List of Holders. 31 30 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 33 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 34 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 36 Section 5.9 ADS Fees and ChargesCharges of Depositary. 38 37 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 39 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 40 ARTICLE VII MISCELLANEOUS 42 41 Section 7.1 Counterparts. 42 41 Section 7.2 No Third-Party Beneficiaries. 42 41 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 42 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 44 Section 7.8 Compliance with U.S. Securities Laws. 45 44 Section 7.9 England and Wales Cayman Island Law References. 45 Section 7.10 Titles and References. 46 45 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).A-1

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 Depositary 7 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. 8 Shares 9 Section 2.4 Registration and Safekeeping of Deposited Securities. Securities 10 Section 2.5 Issuance of ADSs. 10 ADSs 11 Section 2.6 Transfer, Combination and Split-up of ADRs. ADRs 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. etc 13 Section 2.9 Lost ADRs, etc. etc 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. Records 14 Section 2.11 Escheatment. Escheatment 14 Section 2.12 Partial Entitlement ADSs. 14 ADSs 15 Section 2.13 Certificated/Uncertificated ADSs. ADSs 15 Section 2.14 Restricted ADSs. 16 ADSs 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. Information 18 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 19 Section 3.3 Representations and Warranties on Deposit of Shares. Shares 19 Section 3.4 Compliance with Information Requests. 19 Requests 20 Section 3.5 Ownership Restrictions. 19 Restrictions 20 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 21 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 Distributions 22 Section 4.2 Distribution in Shares. 21 Shares 23 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 23 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 27 Section 4.7 Redemption. 25 Redemption 27 Section 4.8 Conversion of Foreign Currency. 26 Currency 28 Section 4.9 Fixing of ADS Record Date. 27 Date 29 Section 4.10 Voting of Deposited Securities. 27 Securities 29 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 31 Section 4.12 Available Information. 30 Information 32 Section 4.13 Reports. 30 Reports 32 Section 4.14 List of Holders. 31 Holders 32 Section 4.15 Taxation. 31 Taxation 33 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 34 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Xxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 34 Section 5.3 Standard of Care. 33 Care 35 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 36 Section 5.5 The Custodian. 35 Custodian 37 Section 5.6 Notices and Reports. 35 Reports 37 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 etc 38 Section 5.8 Indemnification. 37 Indemnification 39 Section 5.9 ADS Fees and Charges. 38 Charges 40 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 Owners 41 ARTICLE VI AMENDMENT AND TERMINATION 40 41 Section 6.1 Amendment/Supplement. 40 Supplement 41 Section 6.2 Termination. 41 Termination 42 ARTICLE VII MISCELLANEOUS 42 44 Section 7.1 Counterparts. 42 Counterparts 44 Section 7.2 No Third-Third Party Beneficiaries. 42 /Acknowledgments 44 Section 7.3 Severability. 42 Severability 44 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 44 Section 7.5 Notices. 43 Notices 45 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 46 Section 7.7 Assignment. 45 Assignment 47 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 Laws 47 Section 7.9 England and Wales English Law References. 45 References 47 Section 7.10 Titles and References. 46 References 48 EXHIBITS Form of ADR. ADR A-1 Fee Schedule. Schedule B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE•], 20172020, by and among (i) NuCana plcPURETECH HEALTH PLC, a public limited company incorporated under the laws of England and Wales Wales, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 5 Section 2.1 Appointment of Depositary. 6 Section 2.2 Form and Transferability of ADSs. 7 6 Section 2.3 Deposit of Shares. 8 7 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 9 Section 2.5 Issuance of ADSs. 10 9 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 10 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 10 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 12 Section 2.9 Lost ADRs, etc. 14 12 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 13 Section 2.11 Escheatment. 14 13 Section 2.12 Partial Entitlement ADSs. 14 13 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 14 Section 2.14 Restricted ADSs. 16 15 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 17 Section 3.1 Proofs, Certificates and Other Information. 18 17 Section 3.2 Liability for Taxes and Other Charges. 18 17 Section 3.3 Representations and Warranties on Deposit of Shares. 19 18 Section 3.4 Compliance with Information Requests. 19 18 Section 3.5 Ownership Restrictions. 19 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 19 ARTICLE IV THE DEPOSITED SECURITIES 20 19 Section 4.1 Cash Distributions. 20 19 Section 4.2 Distribution in Shares. 21 20 Section 4.3 Elective Distributions in Cash or Shares. 22 21 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 21 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 23 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 24 Section 4.7 Redemption. 25 24 Section 4.8 Conversion of Foreign Currency. 26 25 Section 4.9 Fixing of ADS Record Date. 27 25 Section 4.10 Voting of Deposited Securities. 27 26 Section 4.11 Changes Affecting Deposited Securities. 29 27 Section 4.12 Available Information. 30 28 Section 4.13 Reports. 30 28 Section 4.14 List of Holders. 31 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).29

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. 6 Section 2.2 Form and Transferability of ADSs. 7 6 Section 2.3 Deposit of Shares. 8 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Section 2.5 Issuance of ADSs. 10 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 Section 2.9 Lost ADRs, etc. 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Section 2.11 Escheatment. 14 Section 2.12 Partial Entitlement ADSs. 14 Section 2.13 Certificated/Uncertificated ADSs. 15 Section 2.14 Restricted ADSs. 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. 18 Section 3.2 Liability for Taxes and Other Charges. 18 19 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Section 3.4 Compliance with Information Requests. 19 Section 3.5 Ownership Restrictions. 19 20 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. 20 Section 4.2 Distribution in Shares. 21 Section 4.3 Elective Distributions in Cash or Shares. 22 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 25 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 26 Section 4.7 Redemption. 25 26 Section 4.8 Conversion of Foreign Currency. 26 27 Section 4.9 Fixing of ADS Record Date. 27 Section 4.10 Voting of Deposited Securities. 27 28 Section 4.11 Changes Affecting Deposited Securities. 29 30 Section 4.12 Available Information. 30 31 Section 4.13 Reports. 30 31 Section 4.14 List of Holders. 31 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 33 Section 5.3 Standard of Care. 33 34 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 35 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 36 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 37 Section 5.8 Indemnification. 37 38 Section 5.9 ADS Fees and Charges. 38 39 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Third Party Beneficiaries/Acknowledgments. 42 Section 7.3 Severability. 42 43 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 43 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 44 Section 7.7 Assignment. 45 46 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 46 Section 7.9 England and Wales Cayman Islands Law References. 45 46 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE]November 19, 20172018, by and among (i) NuCana plcWEIDAI LTD., a public an exempted company with limited company incorporated liability registered under the laws of England and Wales the Cayman Islands, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 5 Section 2.1 Appointment of Depositary. 6 Section 2.2 Form and Transferability of ADSs. 7 6 Section 2.3 Deposit of Shares. 8 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 9 Section 2.5 Issuance of ADSs. 10 9 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 10 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 12 Section 2.9 Lost ADRs, etc. 14 13 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 13 Section 2.11 Escheatment. 14 13 Section 2.12 Partial Entitlement ADSs. 14 13 Section 2.13 Certificated/Uncertificated ADSs. 15 14 Section 2.14 Restricted ADSs. 16 15 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 17 Section 3.1 Proofs, Certificates and Other Information. 18 17 Section 3.2 Liability for Taxes and Other Charges. 18 17 Section 3.3 Representations and Warranties on Deposit of Shares. 19 18 Section 3.4 Compliance with Information Requests. 19 18 Section 3.5 Ownership Restrictions. 19 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 19 ARTICLE IV THE DEPOSITED SECURITIES 20 19 Section 4.1 Cash Distributions. 20 19 Section 4.2 Distribution in Shares. 21 20 Section 4.3 Elective Distributions in Cash or Shares. 22 21 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 22 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 23 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 24 Section 4.7 Redemption. 25 24 Section 4.8 Conversion of Foreign Currency. 26 25 Section 4.9 Fixing of ADS Record Date. 27 26 Section 4.10 Voting of Deposited Securities. 27 26 Section 4.11 Changes Affecting Deposited Securities. 29 28 Section 4.12 Available Information. 30 28 Section 4.13 Reports. 30 29 Section 4.14 List of Holders. 31 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).29

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 9 SECTION 2.1 Appointment of Depositary. 6 Section Depositary 9 SECTION 2.2 Form and Transferability of ADSs. 7 Section 9 SECTION 2.3 Deposit of Shares. 8 Section with Custodian 13 SECTION 2.4 Registration and Safekeeping of Deposited Securities. 10 Section Securities 15 SECTION 2.5 Issuance Execution and Delivery of ADSs. 10 Section Receipts 15 SECTION 2.6 Transfer, Combination and Split-up of ADRsADSs and Receipts. 11 Section 16 SECTION 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Section 18 SECTION 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 Section 21 SECTION 2.9 Lost ADRsReceipts, etc. 14 Section etc 22 SECTION 2.10 Cancellation and Destruction of Surrendered ADRsReceipts; Maintenance of Records. 14 Section Records 23 SECTION 2.11 Escheatment. 14 Section 2.12 Partial Entitlement ADSs. 14 Section 2.13 ADSs 23 SECTION 2.12 Certificated/Uncertificated ADSs. 15 Section 2.14 Restricted ADSs. 16 25 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 27 SECTION 3.1 Proofs, Certificates and Other Information. 18 Section Information 27 SECTION 3.2 Liability for Taxes and Other Charges. 18 Section Charges 29 SECTION 3.3 Representations and Warranties on Deposit of Shares. 19 Section Shares 29 SECTION 3.4 Compliance with Information Requests. 19 Section Requests 30 SECTION 3.5 Ownership Restrictions. 19 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Restrictions 30 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 31 SECTION 4.1 Cash Distributions. 20 Section Distributions 31 SECTION 4.2 Distribution in Shares. 21 Section Shares 32 SECTION 4.3 Elective Distributions in Cash or Shares. 22 Section Shares 34 SECTION 4.4 Distribution of Rights to Purchase Additional ADSs. 23 Section 35 SECTION 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Section 38 SECTION 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Section Form 39 SECTION 4.7 Redemption. 25 Section Redemption 40 SECTION 4.8 Conversion of Foreign Currency. 26 Section Currency 41 SECTION 4.9 Fixing of ADS Record Date. 27 Section Date 42 SECTION 4.10 Voting of Deposited Securities. 27 Section Securities 43 SECTION 4.11 Changes Affecting Deposited Securities. 29 Section 4.12 Available Information. 30 Section 4.13 Reports. 30 Section 4.14 List of Holders. 31 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).46

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 7 Section 2.2 Form and Transferability of ADSs. 7 Section 2.3 Deposit of Shares. 8 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Section 2.5 Issuance of ADSs. 10 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 Section 2.9 Lost ADRs, etc. 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Section 2.11 Escheatment. 14 Section 2.12 Partial Entitlement ADSs. 14 15 Section 2.13 Certificated/Uncertificated ADSs. 15 Section 2.14 Restricted ADSs. 16 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. 18 Section 3.2 Liability for Taxes and Other Charges. 18 19 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Section 3.4 Compliance with Information Requests. 19 20 Section 3.5 Ownership Restrictions. 19 20 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. 20 Section 4.2 Distribution in Shares. 21 22 Section 4.3 Elective Distributions in Cash or Shares. 22 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 25 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 26 Section 4.7 Redemption. 25 26 Section 4.8 Conversion of Foreign Currency. 26 27 Section 4.9 Fixing of ADS Record Date. 27 Section 4.10 Voting of Deposited Securities. 27 28 9964064v.4 Section 4.11 Changes Affecting Deposited Securities. 29 30 Section 4.12 Available Information. 30 31 Section 4.13 Reports. 30 31 Section 4.14 List of Holders. 31 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 33 Section 5.3 Standard of Care. 33 34 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 35 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 36 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 37 Section 5.8 Indemnification. 37 38 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 40 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Third‑Party Beneficiaries. 42 43 Section 7.3 Severability. 42 43 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 43 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 44 Section 7.7 Assignment. 45 46 Section 7.8 Compliance with U.S. Securities Laws. 45 46 Section 7.9 England and Wales Law References. 45 46 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE]October 2, 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 4 SECTION 2.1 Appointment of Depositary. 6 Section Depositary 4 SECTION 2.2 Form and Transferability of ADSs. Receipts 5 SECTION 2.3 Deposits 6 SECTION 2.4 Execution and Delivery of Receipts 7 Section 2.3 Deposit SECTION 2.5 Transfer of Shares. 8 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Section 2.5 Issuance of ADSs. 10 Section 2.6 Transfer, Receipts; Combination and Split-up of ADRs. 11 Section 2.7 Receipts 7 SECTION 2.6 Surrender of ADSs Receipts and Withdrawal of Deposited Securities. 11 Section 2.8 Securities 8 SECTION 2.7 Limitations on Execution and Delivery, Transfer, etc. of ADSsReceipts; Suspension of Delivery, Transfer, etc. 13 Section 2.9 9 SECTION 2.8 Lost ADRsReceipts, etc. 14 Section 2.10 9 SECTION 2.9 Cancellation and Destruction of Surrendered ADRsReceipts; Maintenance of RecordsRecords 10 Page SECTION 2.10 Pre-Release 10 SECTION 2.11 Restricted ADSs 10 ARTICLE III. 14 Section 2.11 Escheatment. 14 Section 2.12 Partial Entitlement ADSs. 14 Section 2.13 Certificated/Uncertificated ADSs. 15 Section 2.14 Restricted ADSs. 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section RECEIPTS 11 SECTION 3.1 Proofs, Certificates and Other Information. 18 Section Information 11 SECTION 3.2 Liability for Taxes and Other Charges. 18 Section Charges 12 SECTION 3.3 Representations and Warranties on Deposit of Shares. 19 Section Shares 12 SECTION 3.4 Compliance with Information RequestsRequests 13 ARTICLE IV. 19 Section 3.5 Ownership Restrictions. 19 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 13 SECTION 4.1 Cash Distributions. 20 Section Distributions 13 SECTION 4.2 Distribution in Shares. 21 Section Shares 14 SECTION 4.3 Elective Distributions in Cash or Shares. 22 Section Shares 14 SECTION 4.4 Distribution of Rights to Purchase Additional ADSs. 23 Section Shares 15 SECTION 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Section Shares 16 SECTION 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Section 4.7 Redemption. 25 Section 4.8 Conversion of Foreign Currency. 26 Section 4.9 Currency 17 SECTION 4.7 Fixing of ADS Record Date. 27 Section 4.10 Date 17 SECTION 4.8 Voting of Deposited Securities. 27 Section 4.11 Securities 18 SECTION 4.9 Changes Affecting Deposited Securities. 29 Section Securities 19 SECTION 4.10 Available Information 19 SECTION 4.11 Reports 20 SECTION 4.12 Available Information. 30 Section 4.13 Reports. 30 Section 4.14 List of Holders. 31 Section 4.15 Holders 20 SECTION 4.13 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).Withholding 20

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 Depositary 7 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. 8 with Custodian 9 Section 2.4 Registration and Safekeeping of Deposited Securities. Securities 10 Section 2.5 Issuance of ADSs. 10 ADSs 11 Section 2.6 Transfer, Combination and Split-up of ADRs. ADRs 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 14 Section 2.9 Lost ADRs, etc. etc 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 15 Section 2.11 Escheatment. 14 Escheatment 15 Section 2.12 Partial Entitlement ADSs. 14 ADSs 15 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 16 Section 2.14 Restricted ADSs. 16 ADSs 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 Information 19 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 20 Section 3.4 Compliance with Information Requests. 19 Requests 21 Section 3.5 Ownership Restrictions. 19 Restrictions 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 21 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 Distributions 22 Section 4.2 Distribution in Shares. 21 Shares 23 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 27 Section 4.7 Redemption. 25 Redemption 28 Section 4.8 Conversion of Foreign Currency. 26 Currency 28 Section 4.9 Fixing of ADS Record Date. 27 Date 29 Section 4.10 Voting of Deposited Securities. 27 Securities 30 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 31 Section 4.12 Available Information. 30 Information 32 Section 4.13 Reports. 30 Reports 33 Section 4.14 List of Holders. 31 Holders 33 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).Taxation 33

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. Depositary 6 Section 2.2 Form and Transferability of ADSs. 7 ADSs 6 Section 2.3 Deposit of Shares. Shares 8 Section 2.4 Registration and Safekeeping of Deposited Securities. Securities 10 Section 2.5 Issuance of ADSs. ADSs 10 Section 2.6 Transfer, Combination and Split-up of ADRs. ADRs 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. Securities 11 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. etc 13 Section 2.9 Lost ADRs, etc. 14 etc 13 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. Records 14 Section 2.11 Escheatment. Escheatment 14 Section 2.12 Partial Entitlement ADSs. ADSs 14 Section 2.13 Certificated/Uncertificated ADSs. ADSs 15 Section 2.14 Restricted ADSs. ADSs 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. Information 18 Section 3.2 Liability for Taxes and Other Charges. Charges 18 Section 3.3 Representations and Warranties on Deposit of Shares. Shares 19 Section 3.4 Compliance with Information Requests. Requests 19 Section 3.5 Ownership Restrictions. 19 Restrictions 20 Section 3.6 Reporting Obligations and Regulatory Approvals. Approvals 20 ARTICLE IV THE DEPOSITED SECURITIES 20 21 Section 4.1 Cash Distributions. 20 Distributions 21 Section 4.2 Distribution in Shares. 21 Shares 22 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 23 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 24 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 25 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 26 Section 4.7 Redemption. 25 Redemption 26 Section 4.8 Conversion of Foreign Currency. 26 Currency 27 Section 4.9 Fixing of ADS Record Date. 27 Date 28 Section 4.10 Voting of Deposited Securities. 27 Securities 28 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 30 Section 4.12 Available Information. 30 Information 31 Section 4.13 Reports. 30 Reports 31 Section 4.14 List of Holders. Holders 31 Section 4.15 Taxation. Taxation 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 33 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Xxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 33 Section 5.3 Standard of Care. 33 Care 34 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 35 Section 5.5 The Custodian. 35 Custodian 36 Section 5.6 Notices and Reports. 35 Reports 36 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 etc 37 Section 5.8 Indemnification. 37 Indemnification 38 Section 5.9 ADS Fees and Charges. 38 Charges 39 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. Owners 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. Supplement 40 Section 6.2 Termination. Termination 41 ARTICLE VII MISCELLANEOUS 42 43 Section 7.1 Counterparts. 42 Counterparts 43 Section 7.2 No Third-Third Party Beneficiaries. 42 /Acknowledgments 43 Section 7.3 Severability. 42 Severability 43 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 44 Section 7.5 Notices. 43 Notices 44 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 45 Section 7.7 Assignment. 45 Assignment 46 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 Laws 46 Section 7.9 England and Wales English Law References. 45 References 47 Section 7.10 Titles and References. 46 References 47 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE]___________, 20172021, by and among (i) NuCana Immunocore Holdings plc, a public limited company incorporated under the laws of England and Wales Wales, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 Depositary 7 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. 8 Shares 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 11 Section 2.5 Issuance of ADSs. 10 ADSs 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 etc 14 Section 2.9 Lost ADRs, etc. 14 etc 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 15 Section 2.11 Escheatment. 14 Escheatment 15 Section 2.12 Partial Entitlement ADSs. 14 ADSs 16 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 17 Section 2.14 Restricted ADSs. 16 ADSs 18 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND HOLDERSAND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. 18 Information 19 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 20 Section 3.4 Compliance with Information Requests. 19 Requests 21 Section 3.5 Ownership Restrictions. 19 Restrictions 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 21 Section 3.7 Disclosure of Interest 21 ARTICLE IV THE DEPOSITED SECURITIES 20 24 Section 4.1 Cash Distributions. 20 Distributions 24 Section 4.2 Distribution in Shares. 21 Shares 25 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 25 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 Shares in the Form of ADSs 26 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 28 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 [RESERVED] 29 Section 4.7 Redemption. 25 Redemption 29 Section 4.8 Conversion of Foreign Currency. 26 Currency 30 Section 4.9 Fixing of ADS Record Date. 27 Date 30 Section 4.10 Voting of Deposited Securities. 27 Securities 31 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 33 Section 4.12 Available Information. 30 Information 34 Section 4.13 Reports. 30 Reports 34 Section 4.14 List of Holders. 31 Holders 34 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).Taxation 34

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 Depositary 7 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. 8 Shares 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 11 Section 2.5 Issuance of ADSs. 10 ADSs 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 14 Section 2.9 Lost ADRs, etc. 14 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 15 Section 2.11 Escheatment. 14 Escheatment 15 Section 2.12 Partial Entitlement ADSs. 14 ADSs 16 Section 2.13 Certificated/Uncertificated ADSs. 15 ADSs 17 Section 2.14 Restricted ADSs. 16 ADSs 18 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 Information 19 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 20 Section 3.4 Compliance with Information Requests. 19 Requests 21 Section 3.5 Ownership Restrictions. 19 Restrictions 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 21 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 Distributions 22 Section 4.2 Distribution in Shares. 21 Shares 23 Section 4.3 Elective Distributions in Cash or Shares. 22 Shares 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 ADSs 25 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 26 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 27 Section 4.7 Redemption. 25 Redemption 27 Section 4.8 Conversion of Foreign Currency. 26 Currency 28 Section 4.9 Fixing of ADS Record Date. 27 Date 29 Section 4.10 Voting of Deposited Securities. 27 Securities 29 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 32 Section 4.12 Available Information. 30 Information 32 Section 4.13 Reports. 30 Reports 32 Section 4.14 List of Holders. 31 Holders 32 Section 4.15 Taxation. 31 Taxation 35 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 34 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Xxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 34 Section 5.3 Standard of Care. 33 Care 35 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 36 Section 5.5 The Custodian. 35 Custodian 37 Section 5.6 Notices and Reports. 35 Reports 37 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 38 Section 5.8 Indemnification. 37 Indemnification 39 Section 5.9 ADS Fees and Charges. 38 Charges 40 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 Owners 41 ARTICLE VI AMENDMENT AND TERMINATION 40 42 Section 6.1 Amendment/Supplement. 40 Supplement 42 Section 6.2 Termination. 41 Termination 42 ARTICLE VII MISCELLANEOUS 42 44 Section 7.1 Counterparts. 42 Counterparts 44 Section 7.2 No Third-Party Beneficiaries. 42 /Acknowledgments 44 Section 7.3 Severability. 42 Severability 44 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 45 Section 7.5 Notices. 43 Notices 45 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 46 Section 7.7 Assignment. 45 Assignment 47 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 Laws 47 Section 7.9 England and Wales The British Virgin Islands Law References. 45 References 48 Section 7.10 Titles and References. 46 References 48 EXHIBITS Form of ADR. ADR A-1 Fee Schedule. Schedule B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE●], 20172019, by and among (i) NuCana plcANPAC BIO-MEDICAL SCIENCE CO., LTD., a public business company limited company by shares incorporated under in the laws of England and Wales British Virgin Islands, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. 6 Section 2.2 Form and Transferability of ADSs. 7 6 Section 2.3 Deposit of Shares. 8 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 9 Section 2.5 Issuance of ADSs. 10 9 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 10 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 12 Section 2.9 Lost ADRs, etc. 14 13 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 13 Section 2.11 Escheatment. 14 13 Section 2.12 Partial Entitlement ADSs. 14 Section 2.13 Certificated/Uncertificated ADSs. 15 Section 2.14 Restricted ADSs. 16 17 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. 18 Section 3.2 Liability for Taxes and Other Charges. 18 19 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Section 3.4 Compliance with Information Requests. 19 20 Section 3.5 Ownership Restrictions. 19 20 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. 20 21 Section 4.2 Distribution in Shares. 21 Section 4.3 Elective Distributions in Cash or Shares. 22 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Section 4.7 Redemption. 25 Section 4.8 Conversion of Foreign Currency. 26 Section 4.9 Fixing of ADS Record Date. 27 Section 4.10 Voting of Deposited Securities. 27 Section 4.11 Changes Affecting Deposited Securities. 29 Section 4.12 Available Information. 30 Section 4.13 Reports. 30 Section 4.14 List of Holders. 31 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).30

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. Depositary 6 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. Shares 8 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Section 2.5 Issuance of ADSs. 10 Section 2.6 Transfer, Combination and Split-up of ADRs. ADRs 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. Securities 11 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 12 Section 2.9 Lost ADRs, etc. 14 .. 13 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 13 Section 2.11 Escheatment. 14 Section 2.12 Partial Entitlement ADSs. ADSs 14 Section 2.13 Certificated/Uncertificated ADSs. ADSs 15 Section 2.14 Restricted ADSs. ADSs 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 17 Section 3.1 Proofs, Certificates and Other Information. 18 Information 17 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 17 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 18 Section 3.4 Compliance with Information Requests. 19 18 Section 3.5 Ownership Restrictions. 19 Restrictions 18 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 Approvals 19 ARTICLE IV THE DEPOSITED SECURITIES 20 19 Section 4.1 Cash Distributions. 20 19 Section 4.2 Distribution in Shares. 21 20 Section 4.3 Elective Distributions in Cash or Shares. 22 21 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 22 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase SharesShares 23 Section 4.6 [Intentionally Omitted]. 24 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Section 4.7 Redemption. 25 24 Section 4.8 Conversion of Foreign Currency. 26 25 Section 4.9 Fixing of ADS Record Date. 27 26 Section 4.10 Voting of Deposited Securities. 27 26 Section 4.11 Changes Affecting Deposited Securities. 29 28 Section 4.12 Available Information. 30 29 Section 4.13 Reports. 30 Reports 29 Section 4.14 List of Holders. 31 Holders 29 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), Taxation 29 (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 Section 2.1 Appointment of Depositary. Depositary 6 Section 2.2 Form and Transferability of ADSs. ADSs 7 Section 2.3 Deposit of Shares. Shares 8 Section 2.4 Registration and Safekeeping of Deposited Securities. Securities 10 Section 2.5 Issuance of ADSs. ADSs 10 Section 2.6 Transfer, Combination and Split-up of ADRs. ADRs 11 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 12 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. etc 13 Section 2.9 Lost ADRs, etc. etc 14 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. Records 14 Section 2.11 Escheatment. Escheatment 14 Section 2.12 Partial Entitlement ADSs. ADSs 14 Section 2.13 Certificated/Uncertificated ADSs. ADSs 15 Section 2.14 Restricted ADSs. ADSs 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 Section 3.1 Proofs, Certificates and Other Information. Information 18 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 19 Section 3.3 Representations and Warranties on Deposit of Shares. Shares 19 Section 3.4 Compliance with Information Requests. 19 Requests 20 Section 3.5 Ownership Restrictions. 19 Restrictions 20 Section 3.6 Reporting Obligations and Regulatory Approvals. Approvals 20 ARTICLE IV THE DEPOSITED SECURITIES 20 21 Section 4.1 Cash Distributions. 20 Distributions 21 Section 4.2 Distribution in Shares. Shares 21 Section 4.3 Elective Distributions in Cash or Shares. Shares 22 Section 4.4 Distribution of Rights to Purchase Additional ADSs. ADSs 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Shares 25 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Form 26 Section 4.7 Redemption. 25 Redemption 26 Section 4.8 Conversion of Foreign Currency. 26 Currency 27 Section 4.9 Fixing of ADS Record Date. 27 Date 28 Section 4.10 Voting of Deposited Securities. 27 Securities 28 Section 4.11 Changes Affecting Deposited Securities. 29 Securities 30 Section 4.12 Available Information. 30 Information 31 Section 4.13 Reports. 30 Reports 32 Section 4.14 List of Holders. 31 Holders 32 Section 4.15 Taxation. 31 Taxation 32 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 33 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Rxxxxxxxx 00 Section 5.2 Exoneration. 32 Exoneration 34 Section 5.3 Standard of Care. 33 Care 34 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Depositary 35 Section 5.5 The Custodian. 35 Custodian 36 Section 5.6 Notices and Reports. 35 Reports 37 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 etc 37 Section 5.8 Indemnification. 37 Indemnification 38 Section 5.9 ADS Fees and Charges. 38 Charges 39 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. Owners 40 ARTICLE VI AMENDMENT AND TERMINATION 40 41 Section 6.1 Amendment/Supplement. 40 Supplement 41 Section 6.2 Termination. Termination 41 ARTICLE VII MISCELLANEOUS 42 43 Section 7.1 Counterparts. 42 Counterparts 43 Section 7.2 No Third-Third Party Beneficiaries. 42 /Acknowledgments 43 Section 7.3 Severability. 42 Severability 43 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Effect 43 Section 7.5 Notices. 43 Notices 44 Section 7.6 Governing Law and Jurisdiction. 43 Jurisdiction 45 Section 7.7 Assignment. 45 Assignment 46 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 Laws 46 Section 7.9 England and Wales English Law References. 45 References 47 Section 7.10 Titles and References. 46 References 47 EXHIBITS Form of ADR. ADR A-1 Fee Schedule. Schedule B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of September [DATE●], 20172019, by and among (i) NuCana Amryt Pharma Holdings plc, a public limited company incorporated under the laws of England and Wales Wales, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America America, and its successors (“Citibank”) acting in its capacity as depositarydepositary under the terms of this Deposit Agreement, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 ADSs 8 Section 2.1 Appointment of Depositary. 6 Depositary 8 Section 2.2 Form and Transferability of ADSs. 7 ADSs 8 Section 2.3 Deposit of Shares. 8 Shares 10 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 Securities 11 Section 2.5 Issuance of ADSs. 10 ADSs 12 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 ADRs 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 Securities 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSsADRs; Suspension of Delivery, Transfer, etc. 13 etc 14 Section 2.9 Lost ADRs, etc. 14 etc 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 Records 16 Section 2.11 Escheatment. 14 Partial Entitlement ADSs 16 Section 2.12 Partial Entitlement ADSs. 14 Section 2.13 Certificated/Uncertificated ADSsADSs 17 Section 2.13 Restricted ADSs 18 ARTICLE III. 15 Section 2.14 Restricted ADSs. 16 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 20 Section 3.1 Proofs, Certificates and Other Information. 18 Information 20 Section 3.2 Liability for Taxes and Other Charges. 18 Charges 21 Section 3.3 Representations and Warranties on Deposit of Shares. 19 Shares 21 Section 3.4 Compliance with Information Requests. 19 Requests 22 Section 3.5 Ownership Restrictions. 19 [Intentionally Omitted] 22 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 ARTICLE IV THE DEPOSITED SECURITIES 20 Section 4.1 Cash Distributions. 20 Section 4.2 Distribution in Shares. 21 Section 4.3 Elective Distributions in Cash or Shares. 22 Section 4.4 Distribution Disclosure of Rights to Purchase Additional ADSs. 23 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 Section 4.7 Redemption. 25 Section 4.8 Conversion of Foreign Currency. 26 Section 4.9 Fixing of ADS Record Date. 27 Section 4.10 Voting of Deposited Securities. 27 Section 4.11 Changes Affecting Deposited Securities. 29 Section 4.12 Available Information. 30 Section 4.13 Reports. 30 Section 4.14 List of Holders. 31 Section 4.15 Taxation. 31 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 Section 5.2 Exoneration. 32 Section 5.3 Standard of Care. 33 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 Section 5.5 The Custodian. 35 Section 5.6 Notices and Reports. 35 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 Section 5.8 Indemnification. 37 Section 5.9 ADS Fees and Charges. 38 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 ARTICLE VI AMENDMENT AND TERMINATION 40 Section 6.1 Amendment/Supplement. 40 Section 6.2 Termination. 41 ARTICLE VII MISCELLANEOUS 42 Section 7.1 Counterparts. 42 Section 7.2 No Third-Party Beneficiaries. 42 Section 7.3 Severability. 42 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 Section 7.5 Notices. 43 Section 7.6 Governing Law and Jurisdiction. 43 Section 7.7 Assignment. 45 Section 7.8 Compliance with U.S. Securities Laws. 45 Section 7.9 England and Wales Law References. 45 Section 7.10 Titles and References. 46 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 DEPOSIT AGREEMENT DEPOSIT AGREEMENT, dated as of [DATE], 2017, by and among (i) NuCana plc, a public limited company incorporated under the laws of England and Wales and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).Interests 22

Appointment of Depositary. FORM OF RECEIPTS; DEPOSIT OF SHARES; EXECUTION AND DELIVERY, TRANSFER AND SURRENDER OF RECEIPTS 6 7 Section 2.1 Appointment of Depositary. 6 7 Section 2.2 Form and Transferability of ADSs. 7 8 Section 2.3 Deposit of Shares. 8 9 Section 2.4 Registration and Safekeeping of Deposited Securities. 10 11 Section 2.5 Issuance of ADSs. 10 11 Section 2.6 Transfer, Combination and Split-up of ADRs. 11 12 Section 2.7 Surrender of ADSs and Withdrawal of Deposited Securities. 11 13 Section 2.8 Limitations on Execution and Delivery, Transfer, etc. of ADSs; Suspension of Delivery, Transfer, etc. 13 14 Section 2.9 Lost ADRs, etc. 14 15 Section 2.10 Cancellation and Destruction of Surrendered ADRs; Maintenance of Records. 14 15 Section 2.11 Escheatment. 14 15 Section 2.12 Partial Entitlement ADSs. 14 15 Section 2.13 Certificated/Uncertificated ADSs. 15 16 Section 2.14 Restricted ADSs. 16 18 ARTICLE III CERTAIN OBLIGATIONS OF HOLDERS AND BENEFICIAL OWNERS OF ADSs 18 19 Section 3.1 Proofs, Certificates and Other Information. 18 19 Section 3.2 Liability for Taxes and Other Charges. 18 20 Section 3.3 Representations and Warranties on Deposit of Shares. 19 20 Section 3.4 Compliance with Information Requests. 19 21 Section 3.5 Ownership Restrictions. 19 21 Section 3.6 Reporting Obligations and Regulatory Approvals. 20 22 ARTICLE IV THE DEPOSITED SECURITIES 20 22 Section 4.1 Cash Distributions. 20 22 Section 4.2 Distribution in Shares. 21 23 Section 4.3 Elective Distributions in Cash or Shares. 22 24 Section 4.4 Distribution of Rights to Purchase Additional ADSs. 23 25 Section 4.5 Distributions Other Than Cash, Shares or Rights to Purchase Shares. 24 27 Section 4.6 Distributions with Respect to Deposited Securities in Bearer Form. 25 28 Section 4.7 Redemption. 25 28 Section 4.8 Conversion of Foreign Currency. 26 28 Section 4.9 Fixing of ADS Record Date. 27 29 Section 4.10 Voting of Deposited Securities. 27 30 Section 4.11 Changes Affecting Deposited Securities. 29 31 Section 4.12 Available Information. 30 32 Section 4.13 Reports. 30 32 Section 4.14 List of Holders. 31 33 Section 4.15 Taxation. 31 33 ARTICLE V THE DEPOSITARY, THE CUSTODIAN AND THE COMPANY 32 34 Section 5.1 Maintenance of Office and Transfer Books by the Registrar. 32 34 Section 5.2 Exoneration. 32 35 Section 5.3 Standard of Care. 33 35 Section 5.4 Resignation and Removal of the Depositary; Appointment of Successor Depositary. 34 36 Section 5.5 The Custodian. 35 37 Section 5.6 Notices and Reports. 35 38 Section 5.7 Issuance of Additional Shares, ADSs etc. 36 39 Section 5.8 Indemnification. 37 40 Section 5.9 ADS Fees and Charges. 38 41 Section 5.10 Pre-Release Transactions. 39 Section 5.11 Restricted Securities Owners. 40 42 ARTICLE VI AMENDMENT AND TERMINATION 40 42 Section 6.1 Amendment/Supplement. 40 42 Section 6.2 Termination. 41 43 ARTICLE VII MISCELLANEOUS 42 44 Section 7.1 Counterparts. 42 44 Section 7.2 No Third-Third Party Beneficiaries/Acknowledgments. 42 45 Section 7.3 Severability. 42 45 Section 7.4 Holders and Beneficial Owners as Parties; Binding Effect. 42 45 Section 7.5 Notices. 43 46 Section 7.6 Governing Law and Jurisdiction. 43 47 Section 7.7 Assignment. 45 49 Section 7.8 Compliance with with, and No Disclaimer under, U.S. Securities Laws. 45 49 Section 7.9 England and Wales Israeli Law References. 45 49 Section 7.10 Titles and References. 46 49 Section 7.11 Amendment and Restatement. 50 EXHIBITS Form of ADR. A-1 Fee Schedule. B-1 SECOND AMENDED AND RESTATED DEPOSIT AGREEMENT SECOND AMENDED AND RESTATED DEPOSIT AGREEMENT, dated as of [DATE]December 4, 20172018, by and among (i) NuCana plcTEVA PHARMACEUTICAL INDUSTRIES LIMITED, a public limited company incorporated under the laws of England and Wales the State of Israel, and its successors (the “Company”), (ii) CITIBANK, N.A., a national banking association organized under the laws of the United States of America (“Citibank”) acting in its capacity as depositary, and any successor depositary hereunder (Citibank in such capacity, the “Depositary”), and (iii) all Holders and Beneficial Owners of American Depositary Shares issued hereunder (all such capitalized terms as hereinafter defined).