CAMBRIDGE, MA, September 10, 2003 - To mark the opening of a new manufacturing facility next to its Cambridge headquarters, Therion Biologics Corporation today will host a ribbon cutting ceremony with guest of honor, Governor Mitt Romney. The event will be held at 11:00 a.m. at 72 Rogers Street in Cambridge. Joining Governor Romney, state and local government officials and leaders of the local biotechnology community will be present to commemorate the completion of Therion's state-of-the art facility.

"Our new manufacturing facility will supply the upcoming Phase II clinical trials of our two lead vaccine candidates, PANVAC-VF for pancreatic cancer and PROSTVAC^�-VF for prostate cancer, and has the capacity to produce commercial vaccine quantities," said Mark Leuchtenberger, President and Chief Executive Officer of Therion Biologics Corporation. "We are honored to celebrate this momentous occasion with Governor Romney. His presence here today is a testament to his ongoing support of the Commonwealth's biotechnology industry."

"I applaud Therion Biologics for deciding to expand its manufacturing facilities here in Massachusetts and create new jobs for the citizens of the Commonwealth," said Governor Romney. "Our state is home to cutting-edge research institutions, an unparalleled R&D; sector supported by nearly 120 colleges and universities, and a highly educated work force. Expanding manufacturing capabilities here will prove to be a tremendous opportunity for both the state and local economies."

"Therion's decision to grow its manufacturing capabilities within Massachusetts provides another example of the biotechnology industry's critical contributions to the state's economic growth and development," said Janice T. Bourque, President of the Massachusetts Biotechnology Council. "By keeping these capabilities within Massachusetts, Therion is helping to maintain the Commonwealth's status as a leader in biotechnology innovation."

About Therion Biologics Corporation
Therion Biologics Corporation develops therapeutic vaccines for cancer and preventive vaccines for AIDS. The Company has two lead programs involving multiple clinical trials: PANVAC-VF for pancreatic cancer and PROSTVAC^�-VF for prostate cancer. Therion is also applying its technology platform to develop vaccines to treat melanoma, breast cancer and other solid tumors. In addition to studies conducted under collaboration agreements with the National Cancer Institute, the Company's strategic partners include 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.