ImmunoGen, Inc. Announces Presentation of Favorable SAR3419 Interim Clinical Data at ASCO

– Novel Targeted Therapy for Non-Hodgkin’s Lymphoma Demonstrates Impressive Efficacy in Early Stage Clinical Trial –

WALTHAM, Mass.--(BUSINESS WIRE)-- ImmunoGen, Inc. (Nasdaq: IMGN), a biotechnology company that develops targeted antibody-based anticancer products using its antibody expertise and Targeted Antibody Payload (TAP) technology, today announced the presentation of favorable clinical data for SAR3419 in the treatment of B-cell non-Hodgkin’s lymphoma (NHL). These data were presented at the ASCO 2011 Annual Meeting taking place in Chicago, IL. SAR3419, which uses the Company’s TAP technology, was initially developed by ImmunoGen and licensed to Sanofi preclinically as part of a broader collaboration.

“We believe the promising SAR3419 clinical data presented today further validate our TAP technology and the potential of our deep pipeline,” said Daniel Junius, President and CEO. “SAR3419 has shown impressive efficacy and tolerability in the heavily pretreated patients enrolled in this study, half of whom were refractory to rituximab. Sanofi plans to aggressively develop SAR3419, starting with advancing it into Phase II testing later this year.”

In the trial reported today, patients received SAR3419 dosed weekly for eight weeks, with longer treatment possible. New cohorts of patients received increasingly greater doses of SAR3419 until its maximum tolerated dose (MTD) was defined. Additional patients were treated with SAR3419 at this MTD in the expansion phase of the trial.

The encouraging clinical data presented today included:

  • 33% (7/21) of patients treated with SAR3419 at its MTD (55 mg/m2/week) had an objective response (CR/PR).
  • The duration of responses has ranged from five weeks to at least 55 weeks, with three patients still responding at the time of data cut-off for presentation.
  • Among patients who received any dose level of SAR3419 for whom histological data was available, tumor shrinkage of more than 20% was reported in:
    • 50% (8/16) of patients with diffuse large B-cell lymphoma;
    • 46% (7/15) of patients with follicular lymphoma; and
    • 50% (2/4) of patients with mantle cell lymphoma.
  • Benefit was seen with both indolent and aggressive NHL.
  • SAR3419 is well tolerated. Of particular note is the lack of significant myelosuppression associated with SAR3419 treatment, which is appealing for use in combination with standard chemotherapy agents.

It was identified that further improvement in the tolerability of SAR3419 might be achieved by switching to a bi-weekly dosing regimen after steady state pharmacokinetics were achieved, as some toxicities occurred only after 6-8 treatment cycles (e.g., the one case of Grade 3 ocular toxicity reported, which was reversible). Following protocol amendment, SAR3419 is now being evaluated dosed weekly for 4 weeks followed by dosing every other week for another 4 doses.

About the Clinical Trial

The data reported today are from an ongoing Phase I trial in patients with relapsed or relapsed/refractory CD19-expressing B-cell non-Hodgkin’s lymphoma. Almost all of the patients were categorized as having stage III or IV lymphoma at study entry. The patients had received a median of three prior treatment regimens, and about half of the patients had rituximab-resistant disease. Nineteen of the forty-four patients enrolled had previously received a stem cell transplant. The SAR3419 doses evaluated ranged from 10-70 mg/m2/week.

Additional data from this trial will be presented at the International Conference on Malignant Lymphoma meeting in Lugano, Switzerland later this month.

About SAR3419

SAR3419 was developed by ImmunoGen and licensed to Sanofi as part of a broader collaboration. It consists of a CD19-targeting antibody developed by ImmunoGen with the Company’s DM4 cell-killing agent attached using one of ImmunoGen’s engineered linkers.

About B-cell Non-Hodgkin’s Lymphoma

B-cell lymphomas comprise approximately 85% of non-Hodgkin’s lymphomas in the United States and account for about 4% of all cancers. In 2010, over 65,000 people will be diagnosed with NHL and 20,000 people will die from it. The 5-year survival rate for this disease is around 67%.1

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 currently six TAP compounds in the clinic, with a wealth of clinical data reported with the technology. ImmunoGen’s collaborative partners include Amgen, Bayer HealthCare Pharmaceuticals, Biotest, Genentech (a member of the Roche Group), Novartis, 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. More information about ImmunoGen can be found at www.immunogen.com.

1 American Cancer Society, Detailed Guide: What is Non-Hodgkin’s Lymphoma

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 in the Company’s and its collaboration partners’ product programs, including SAR3419, including risks related to uncertainties around clinical studies and 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, 2010 and other reports filed with the Securities and Exchange Commission.



CONTACT:

For Investors:
ImmunoGen, Inc.
Carol Hausner, 781-895-0600
Executive Director, Investor Relations and Corporate Communications
[email protected]
or
For Media:
The Yates Network
Barbara Yates, 781-258-6153

KEYWORDS:   United States  North America  Illinois  Massachusetts

INDUSTRY KEYWORDS:   Health  Biotechnology  Clinical Trials  Oncology  Pharmaceutical

MEDIA: