CAMBRIDGE, MA, February 18, 2003 - Therion Biologics Corporation today announced that Richard J. Meadows has been appointed to the Company's Board of Directors. Mr. Meadows is currently a Venture Advisor at CDP Capital-Technology Ventures in the firm's Biotechnology and Life Sciences investment sector. Mr. Meadows offers Therion over 20 years of experience in the biotechnology and life sciences industries. His most recent position has been as an independent consultant to such companies as PharmaGap, a National Research Council spin-off; the Center for Molecular Medicine and Therapeutics; the Canadian Genetic Diseases Network; and the Canadian Leukemia Studies Group.

"Richard Meadows brings to Therion extensive experience in the strategic management and planning of biotechnology and pharmaceutical companies," said Mark Leuchtenberger, Therion's President and Chief Executive Officer. "Richard's experience in the market introduction of blockbuster therapeutic products will provide Therion with critical knowledge and direction as the Company moves its key cancer vaccines through clinical development."

Mr. Meadows commented, "Given Therion's three promising programs in clinical trials for prostate cancer, pancreatic cancer, and melanoma, I am excited to join the Board of Directors. In my role as a Company director, I will be working closely with members of the Board and Therion's management team to guide the Company during this critical period of late stage product development and commercialization."

Prior to starting his own consulting firm, Mr. Meadows was President and CEO of Dermacor, Inc., the first Canadian company positioned in the research and treatment of chronic skin wounds. Previous to that, he was President and Owner of MST+Resources, a marketing and scientific consulting firm. In addition, he has held several marketing and business development positions at major Canadian pharmaceutical companies including Bristol Myers Pharmaceutical Group and Astra Pharma Canada, Inc. While at Astra, Mr. Meadows was part of the worldwide marketing teams for Prilosec� and Foscarnet�. Mr. Meadows holds a Certificate in Financial Strategy and a Masters of Business Administration from the University of Toronto and a Bachelor's Degree in Science from McGill University.

About Therion Biologics Corporation
Therion Biologics Corporation develops therapeutic vaccines for cancer and preventive vaccines for AIDS. The Company has three lead programs involving multiple clinical trials: PROSTVAC-VF/TRICOM� for prostate cancer; CEA/MUC- 1-VF/TRICOM for pancreatic cancer; and VF/TRICOM for melanoma. Therion is also applying its technology platform to develop vaccines to treat breast cancer and other solid tumors. The Company's strategic partners include the National Cancer Institute, a global network of leading clinical institutions, and Aventis Pasteur, Ltd., which is developing ALVAC-CEA/B7.1, a clinical candidate for colon cancer. Therion is headquartered in Cambridge, Massachusetts.