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WALTHAM, Mass.--([ BUSINESS WIRE ])--[ ImmunoGen, Inc ]. (NASDAQ: IMGN), a biotechnology company that develops targeted antibody-based anticancer products, today announced that there will be four presentations at the upcoming 2012 American College of Clinical Oncology (ASCO) Annual Meeting on compounds that utilize the Companyas Targeted Antibody Payload (TAP) technology. Of particular note, the findings in the trastuzumab emtansine EMILIA PhaseIII trial will be featured in an ASCO plenary session on June 3, and findings with SAR3419 administered with its Phase II dosing schedule will be reported in a poster presentation on June 4, 2012. Trastuzumab emtansine and SAR3419 are in development by Roche and Sanofi, respectively, under agreements with ImmunoGen.

"Results from a phase Ib study of trastuzumab emtansine, paclitaxel, and pertuzumab in patients with HER2-positive metastatic breast cancer previously treated with trastuzumab."

aASCOas decision to feature the EMILIA data in a plenary session speaks to the significance they attach to the findings,a commented Daniel Junius, President and CEO. aWe developed our TAP technology to enable the creation of better anticancer therapies, and the data reported to date with trastuzumab emtansine support that it can offer meaningful efficacy and tolerability advantages. On June 6 the body of data for trastuzumab emtansine will advance to a new level with the presentation of the findings from its first Phase III trial.a

Mr. Junius continued, aThere are many other TAP compounds advancing through both our own product programs and those of our partners. Weare particularly pleased that Phase I data with SAR3419 administered with its Phase II dosing schedule also will be reported at ASCO. While trastuzumab emtansine helps demonstrate the significance of our technology in a solid tumor indication, SAR3419 is well positioned to help demonstrate this in liquid tumor indications.a

Trastuzumab Emtansine Presentations

• June 2, Breast Cancer - HER2/ER Poster Discussion Session, Display: 1:15 - 5:15 pm in E450a. Discussion: 4:45 - 5:45 PM in E Hall D2.
  
  aResults from a phase Ib study of trastuzumab emtansine, paclitaxel, and pertuzumab in patients with HER2-positive metastatic breast cancer previously treated with trastuzumab.a Abstract #528. Poster Board #18. Presenter: Shanu Modi, MD.
  
  aCardiac safety in a phase II study of trastuzumab emtansine following anthracycline-based chemotherapy as adjuvant or neoadjuvant therapy for early-stage HER2-positive breast cancer.a Abstract #532. Poster Board #22. Presenter: Chau T. Dang, MD.

• June 3, Plenary Session, in N Hall B1
  
  1:45 - 2:00 pm aPrimary results from EMILIA, a phase III study of trastuzumab emtansine versus capecitabine and lapatinib in HER2-positive locally advanced or metastatic breast cancer previously treated with trastuzumab and a taxane.a Abstract #LBA1. Presenter: Kimberly L. Blackwell, MD.
  
  2:00 - 2:15 pm Discussion. Discussant: Louis M. Weiner, MD.

SAR3419 Presentation

• June 4, Lymphoma and Plasma Cell Disorders General Poster Session, 1:15 - 5:15 pm in S Hall A2.
  
  aPhase I study cohort evaluating an optimized administration schedule of SAR3419, an anti-CD19 DM4-loaded antibody drug conjugate, in patients with CD19-positive relapsed/refractory b-cell non-Hodgkinas lymphoma (NCT00796731).a Abstract #8057. Poster Board: #33F. Presenter: Bertrand Coiffier, MD, PhD.

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 with a wealth of clinical data reported. ImmunoGen's collaborative partners include Amgen, Bayer HealthCare, Biotest, Lilly, 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, including trastuzumab emtansine and SAR3419, including risks related to clinical studies and their 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.