News

WALTHAM, Mass., Nov. 14, 2011 (GLOBE NEWSWIRE) -- ImmunoGen, Inc. (Nasdaq:IMGN), a biotechnology company that develops targeted anticancer products using its antibody expertise and Targeted Antibody Payload (TAP) technology, today announced that the Investigational New Drug (IND) application submitted by Amgen for a second TAP compound is now active. This event triggers a $1 million milestone payment to ImmunoGen.

Earlier this month, the IND for a different Amgen TAP compound also became active and triggered a $1 million milestone payment to ImmunoGen. Both compounds use ImmunoGen's TAP technology with Amgen antibodies to undisclosed targets and are in development by Amgen under an agreement between the companies.

Daniel Junius, President and CEO, commented, "On July 1 — the start of our current fiscal year — there were already six TAP compounds in clinical testing through our own programs and those of our partners, with the most advanced in Phase III. Since then, four more TAP compounds have advanced to having an active IND, and we expect our next wholly owned compound, IMGN853, to reach this stage by June. This progress speaks to the productivity of our technology, our product programs, and our partnerships."

About ImmunoGen, Inc.

ImmunoGen, Inc. develops targeted anticancer therapeutics using the Company's expertise in tumor biology, monoclonal antibodies, potent cancer-cell killing agents and engineered linkers. The Company's TAP technology uses monoclonal antibodies to deliver one of ImmunoGen's proprietary cancer-cell killing agents specifically to tumor cells. There are now numerous TAP compounds in clinical development and a wealth of clinical data reported. ImmunoGen's collaborative partners include Amgen, Bayer HealthCare Pharmaceuticals, Biotest, Novartis, Roche, and Sanofi. The most advanced compound using ImmunoGen's TAP technology, trastuzumab emtansine (T-DM1), is in Phase III testing through the Company's collaboration with Genentech, a member of the Roche Group. More information about ImmunoGen can be found at www.immunogen.com.

This press release includes forward-looking statements. For these statements, ImmunoGen claims the protection of the safe harbor for forward-looking statements provided by the Private Securities Litigation Reform Act of 1995. It should be noted that there are risks and uncertainties related to the development of novel anticancer products by ImmunoGen and the Company's collaborators, including this Amgen compound, including risks related to preclinical and clinical studies, their timings and results. A review of these risks can be found in ImmunoGen's Annual Report on Form 10-K for the fiscal year ended June 30, 2011 and other reports filed with the Securities and Exchange Commission.

CONTACT: For Investors:

         Carol Hausner

         Executive Director,

         Investor Relations and Corporate Communications

         ImmunoGen, Inc.

         (781) 895-0600

         info@immunogen.com

         For Media:

         Barbara Yates

         The Yates Network

         (781) 258-6153