Cambridge, MA, November 17, 1999 - Therion Biologics Corporation announced today the appointment of Richard Woodrich to the newly created position of Senior Vice President of Business Development. Mr. Woodrich brings to Therion over 13 years of corporate development experience in the biotechnology and health care industries, including expertise gained from executive management positions at CytoMed, Inc. and Oculon Corporation.

"Dick's considerable financial knowledge and strategic partnering skills will be valuable additions to our management team," said Dennis L. Panicali, Ph.D., President and Chief Executive Officer of Therion. "Given his record of cultivating strong support for both companies and products, we expect he will play a key role in advancing the development and commercialization of our broad portfolio of therapeutic cancer vaccines." Dr. Panicali noted that Therion currently has seven vaccine products for the treatment of cancer in Phase I and Phase II clinical trials.

Mr. Woodrich joins Therion from his most recent position as Executive Vice President and Chief Operating Officer at CytoMed, Inc., where he oversaw all aspects of corporate development and business operations. While at CytoMed he was also instrumental in negotiating an $18 million licensing and technology asset purchase agreement with UCB Pharma, Inc., and the acquisition of CytoMed's development-stage product candidates by LeukoSite, Inc. Previously, Mr. Woodrich served as President, Chief Operating Officer and Director of Oculon Corporation; Chief Financial Officer of Applied bioTechnology; and Chief Financial Officer of Millipore Corporation. Mr. Woodrich is a graduate of Rensselaer Polytechnic Institute and received his M.B.A. from Harvard Business School.

Therion Biologics Corporation is engaged in the development of therapeutic vaccines for cancer and preventive vaccines for AIDS. Currently, Therion has seven products in Phase I and Phase II clinical development for the treatment of major cancers, including prostate, colorectal and breast cancer and melanoma. The Company also has a major corporate alliance with Pasteur M�rieux Connaught for the development of therapeutic colorectal cancer and melanoma vaccines. Therion is headquartered in Cambridge, Massachusetts.