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WALTHAM, Mass.--([ BUSINESS WIRE ])--[ ImmunoGen, Inc ]. (Nasdaq: IMGN), a biotechnology company that develops anticancer products using its Targeted Antibody Payload (TAP) technology, today announced that Roche has announced positive topline results from its trastuzumab emtansine (T-DM1) EMILIA Phase III trial. Trastuzumab emtansine consists of ImmunoGen's potent cancer-killing agent, DM1, attached to the HER2-targeting antibody, trastuzumab, and is in global development by Roche under an agreement between ImmunoGen and Genentech, a member of the Roche Group.

"Weare delighted with these results and with Rocheas plans to submit trastuzumab emtansine for marketing approval. We look forward to seeing the detailed study data at an upcoming medical meeting."

Roche announced today that the EMILIA patients who were randomized to treatment with trastuzumab emtansine had a significantly longer duration of progression-free survival (PFS) than those randomized to treatment with the control therapy, lapatinib (Tykerb) plus capecitabine (Xeloda). EMILIA is the most advanced trastuzumab emtansine Phase III study, and evaluates the compound for the treatment of HER2-positive metastatic breast cancer (mBC) in patients who have previously received treatment with trastuzumab (Herceptin) and a taxane.

Roche said that, based on these findings, it plans to apply for marketing approval of trastuzumab emtansine for HER2-positive mBC in the US (through Genentech) and in Europe. Roche also noted that the safety profile of trastuzumab emtansine in the EMILIA trial was consistent with previous studies and that final results for overall survival (OS) are not yet mature. PFS and overall survival are co-primary efficacy endpoints of EMILIA.

aThe topline results reported today underscore the significance of trastuzumab emtansine and its potential to help patients,a commented Daniel Junius, President and CEO. aWeare delighted with these results and with Rocheas plans to submit trastuzumab emtansine for marketing approval. We look forward to seeing the detailed study data at an upcoming medical meeting.a

Trastuzumab emtansine is in Phase III testing for treatment of HER2-positive mBC in multiple clinical settings in the EMILIA, MARIANNE, and TH3RESA trials, and in Phase II testing for adjuvant/neoadjuvant use for earlier-stage disease.

Conference Call Information

ImmunoGen is holding a conference call today at 8:00 am ET to discuss this release and also the Companyas advancement of its wholly owned IMGN901 product candidate into Phase II testing. To access the live call by phone, dial 913-312-0982. Passcode is 8250254. The call also may be accessed through the Investor Information section of the Company's website, [ www.immunogen.com ]. Following the live webcast, a replay of the call will be available at the same location through April 6, 2012.

About ImmunoGenas TAP Technology

ImmunoGen developed its TAP technology to achieve more effective, better tolerated anticancer drugs. A TAP compound consists of a manufactured antibody that binds specifically to a target found on tumor cells with one of the Companyas highly potent cancer-killing agents attached as a payload. The antibody serves to target the payload specifically to the cancer cells, and the payload serves to kill the cancer cells. In the case of some compounds that use ImmunoGenas TAP technology (trastuzumab emtansine and ImmunoGenas IMGN529 compound), the antibody component also has meaningful anticancer activity.

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-killing agents specifically to tumor cells. There are now numerous TAP compounds in clinical development with a wealth of clinical data reported. ImmunoGenas collaborative partners include Amgen, Bayer HealthCare, Biotest, Lilly, Novartis, Roche, and Sanofi. The most advanced compound using ImmunoGen's TAP technology, trastuzumab emtansine, 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, including trastuzumab emtansine (T-DM1), including risks related to clinical studies and regulatory submissions, their timings and results. A review of these risks can be found in ImmunoGenas Annual Report on Form 10-K for the fiscal year ended June 30, 2011 and other reports filed with the Securities and Exchange Commission.

Tykerb is a registered trademark of GlaxoSmithKline plc.
Xeloda is a registered trademark of Roche.
Herceptin is a registered trademark of Genentech, a member of the Roche Group.