ImmunoGen, Inc. Announces Conference Call to Discuss its Fourth Quarter and Fiscal Year 2011 Financial Results

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 Company will host a conference call at 4:30 p.m. ET on Wednesday, August 3, 2011, to discuss ImmunoGen's financial results for the three-month period and fiscal year ended June 30, 2011. Management also will provide an update on the Company and guidance for ImmunoGen’s fiscal year ending June 30, 2012.

To access the live call by phone, dial 913-312-0648. Passcode: 5587356. The call also may be accessed through the Investor Information section of the Company's website, http://www.immunogen.com. Following the live webcast, a replay of the call will be available at the same location through August 17, 2011.

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.