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

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

• Contract Type
  Merger Agreement
• 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.