Cambridge, MA, August 22, 2001 - Preparing for advanced clinical trials, Therion Biologics has established two new positions on its management team specifically designed to increase the firm's clinical development capabilities. The company has appointed Jeff Edelson, M.D. as Chief Medical Officer and Senior Vice President of Clinical Development and Michael Wyand, D.V.M., Ph.D. as Senior Vice President of Research and Development. Together, Drs. Edelson and Wyand bring over 20 years of biopharmaceutical experience, both clinical and strategic, to Therion's management team.

"These appointments reflect Therion's commitment to expanding our medical and clinical knowledge, expertise that is critical for the rapid advancement of our two lead cancer vaccines into Phase III clinical trials," said Dennis L. Panicali, Ph.D., President and Chief Executive Officer of Therion. "Given Jeff and Michael's extensive pharmaceutical and business history, we will count on their strong insights and experience to help guide us successfully through pivotal trials." Dr. Panicali noted that both appointments build on Therion's existing scientific and regulatory strengths.

Therion has two lead products in development, PROSTVAC-VF, a vaccine to treat prostate cancer, and ALVAC-CEA/B7.1, a vaccine to treat colorectal cancer being developed by its collaborator, Aventis. Both products have demonstrated safety and have been well tolerated in clinical trials to date. In May, researchers at the American Society of Clinical Oncology (ASCO) meeting reported data showing increased survival time when ALVAC-CEA is used as part of a combination regimen of novel therapeutic vaccines in patients with a variety of late-stage cancers such as colorectal, stomach, pancreatic and other solid tumors. Therion and its collaborators at the National Cancer Institute (NCI) and Aventis Pasteur expect both therapeutic vaccines to enter Phase III trials in the next two years.

Dr. Edelson, whose research experience spans basic, clinical, and health service fields, joins Therion from GlaxoSmithKline where he most recently held the position of Group Director, Clinical Research, Development and Medical Affairs. In this role, he oversaw the design and operation of 12 active clinical development programs. He previously served as a clinician/scientist and Director of Research and Academic Affairs at St. Michael's Hospital in Toronto, Canada. He graduated from the University of Toronto with a M.D. and Masters Degree in Health Administration. Dr. Edelson is a Fellow of the Royal College of Physicians of Canada, American Board of Internal Medicine, and the American College of Chest Physicians.

Dr. Wyand brings 12 years of experience in biopharmaceutical discovery and development to Therion. Prior to joining Therion, Dr. Wyand was President and Chief Scientific Officer of the Mason Division of Primedica Corporation, and most recently, President of Commonwealth LifeSciences, Inc. Throughout his career, he has gained extensive experience in the area of technology assessment, therapeutic drug development, and IND program design of biologics and small molecules including DNA based vaccines. Dr. Wyand received his D.V.M. from Purdue University and his Ph.D. from the University of Connecticut.

Therion Biologics Corporation is focused on the development of therapeutic vaccines for cancer and preventive vaccines for AIDS. Currently, Therion's most advanced product programs, PROSTVAC-VF, in Phase II studies for prostate cancer, and ALVAC-CEA/B7.1, in development for colorectal cancer under a strategic collaboration with Aventis Pasteur, will move into pivotal clinical trials in the next two years. The company also has a broad pipeline of vaccines in early clinical development for treatment of major cancers, including breast cancer, melanoma and other solid tumors. In addition to Aventis, Therion's partners include the National Cancer Institute and a network of leading clinical institutions around the world. Therion is headquartered in Cambridge, Massachusetts.