0001104659-07-076196 Sample Contracts

AGREEMENT AND PLAN OF MERGER BY AND AMONG AVANT IMMUNOTHERAPEUTICS, INC., CALLISTO MERGER CORPORATION AND CELLDEX THERAPEUTICS, INC. Dated as of October 19, 2007

Agreement and Plan of Merger • October 23rd, 2007 • Avant Immunotherapeutics Inc • In vitro & in vivo diagnostic substances • Delaware

• Contract Type
  Agreement and Plan of Merger
• Filed
  October 23rd, 2007
• Company
  Avant Immunotherapeutics Inc
• Industry
  In vitro & in vivo diagnostic substances
• Jurisdiction
  Delaware

AGREEMENT AND PLAN OF MERGER, dated as of October 19, 2007 (the “Agreement”), among AVANT Immunotherapeutics, Inc., a Delaware corporation (“AVANT”), Callisto Merger Corporation, a Delaware corporation and wholly-owned subsidiary of AVANT (“Merger Sub”), Celldex Therapeutics, Inc., a Delaware corporation (“Celldex”).

THIRD AMENDMENT TO AMENDED AND RESTATED EMPLOYMENT AGREEMENT

Employment Agreement • October 23rd, 2007 • Avant Immunotherapeutics Inc • In vitro & in vivo diagnostic substances

• Contract Type
  Employment Agreement
• Filed
  October 23rd, 2007
• Company
  Avant Immunotherapeutics Inc
• Industry
  In vitro & in vivo diagnostic substances

THIS THIRD AMENDMENT TO AMENDED AND RESTATED EMPLOYMENT AGREEMENT (“Amendment”) by and between AVANT Immunotherapeutics, Inc., a Delaware corporation (f/k/a “T Cell Sciences, Inc.,” the “Company”) and Una S. Ryan, Ph.D. (the “Executive”), is dated as of October 19, 2007.