Exhibit 10.3 SIXTH AMENDMENT TO EMPLOYMENT AGREEMENT This AMENDMENT TO EMPLOYMENT AGREEMENT (the " Sixth Amendment") made as of September 2, 2003 between ARIAD Pharmaceuticals, Inc., a Delaware corporation (the "Company"), and David Berstein, Esq....

                                                                    Exhibit 10.3

                     SIXTH AMENDMENT TO EMPLOYMENT AGREEMENT

         This AMENDMENT TO EMPLOYMENT AGREEMENT (the " Sixth Amendment") made as
of September 2, 2003 between ARIAD Pharmaceuticals, Inc., a Delaware corporation
(the "Company"), and Xxxxx Xxxxxxxx, Esq. (the "Employee").

         The Company and the Employee have entered into an Employment Agreement
dated as of August 1, 1993 as previously amended (the "Agreement"), and the
parties hereto desire to further amend certain provisions of the Agreement.

         NOW, THEREFORE, in consideration of the premises set forth herein and
for other good and valuable consideration, the receipt of which is hereby
acknowledged, the parties hereto agree to further amend the Agreement as
follows:

         I.       Term of Employment. The first sentence of Section 2 is hereby
amended to read as follows:

                  "The term of the Employee's employment under the Agreement is
         hereby extended to December 31, 2006 (the "Term"), unless sooner
         terminated pursuant to Section 4 or 5 of this Agreement; provided,
         however, that this Agreement shall automatically be renewed for
         successive one-year terms (the Term and, if the period of employment is
         so renewed, such additional period(s) of employment are collectively
         referred to herein as the "Term") unless terminated by written notice
         given by either party to the other at least 90 days prior to the end of
         the applicable Term."

         II.      This Amendment shall be governed by and construed and enforced
in accordance with the laws of the Commonwealth of Massachusetts applicable to
agreements made and to be performed entirely in Massachusetts.

         III.     Except as modified by this Sixth Amendment, the Agreement
remains in full force and effect and unchanged.

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                  IN WITNESS WHEREOF, the parties have executed this Sixth
Amendment as of the date first written above.

                                         ARIAD PHARMACEUTICALS, INC.

                                         By: /s/ Xxxxxx X. Xxxxxx
                                            -----------------------------
                                            Xxxxxx X. Xxxxxx, M.D.
                                            Chairman and Chief Executive Officer

                                         EMPLOYEE

                                             /s/ Xxxxx X. Xxxxxxxx
                                         --------------------------------
                                         Xxxxx Xxxxxxxx, Esq.

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