CAMBRIDGE, Mass., - October 29, 2004 - Therion Biologics Corporation today announced that Mark Leuchtenberger, President and CEO of Therion, will present a company overview and corporate update at the Mass Opportunities Biotechnology Investment Conference in Boston, Mass. The Therion presentation will take place on November 5, 2004, at 11:10 a.m. ET.

About Therion Biologics Corporation
Therion Biologics Corporation develops therapeutic vaccines that aim to extend and improve the lives of cancer patients. The company has two lead product candidates: PANVAC-VF, currently in a Phase III clinical trial for pancreatic cancer, and PROSTVAC�-VF currently in a Phase II clinical trial for prostate cancer. The company is applying its technology to develop its vaccine pipeline, including treatments for breast cancer, lung cancer, and the prevention of AIDS. For more information, please visit www.therionbio.com.

Contact:
Titus Plattel
Sr. Director, Marketing
Therion Biologics
617.475.7312

# # #