ImmunoGen, Inc. Announces Activity Reported with SAR3419 Plus Rituxan In Difficult-to-Treat Patient Population

ImmunoGen, Inc. Announces Activity Reported with SAR3419 Plus Rituxan In Difficult-to-Treat Patient Population

December 9, 2013

WALTHAM, Mass.--(BUSINESS WIRE)-- ImmunoGen, Inc. (NASDAQ: IMGN), a biotechnology company that develops targeted anticancer therapies using its antibody-drug conjugate (ADC) technology, today announced the presentation of clinical findings with SAR3419 (coltuximab ravtansine) used in combination with Rituxan® (rituximab) to treat diffuse large B-cell lymphoma (DLBCL) that previously had been treated with standard therapies. SAR3419 is a CD19-targeting ADC developed by ImmunoGen and licensed to Sanofi as part of a broader collaboration between the companies. These findings were reported at the annual meeting of the American Society of Hematology (ASH) being held in New Orleans, LA.

The data presented today are from a Phase II trial assessing the activity and safety of SAR3419 when used in combination with Rituxan to treat DLBCL that had previously been treated with standard therapies including Rituxan. A total of 52 patients received SAR3419 and Rituxan in the trial, of which 45 were evaluable for efficacy (the per protocol population).

Nearly three in four (73%) patients enrolled had Stage III/IV disease. Sixty percent (60%) had primary refractory disease and another 16% were refractory to their last treatment regimen; the rest were relapsed but not known to be refractory. Forty percent of the study patients had been treated with three or more prior therapies.

The combination of SAR3419 and Rituxan was found to be generally well tolerated, with no patients discontinuing therapy due to treatment emergent adverse events (TEAEs). The most common TEAEs, of any grade, were asthenia, nausea, cough, diarrhea, and weight decrease. Any ocular events were low grade (1/2), manageable and reversible.

Among the twelve study patients with relapsed but not refractory disease, the objective response rate (ORR) was 58%, with 2 complete responses (CRs) and 5 partial responses (PRs). Among the seven patients with disease refractory to the last treatment, the ORR was 43%, with 0 CRs and 3 PRs reported. Among the 26 patients with primary refractory disease — cancer that had never responded to any treatment — the ORR was 15%, with 2 CRs and 2 PRs reported.

"These data provide additional support for the efficacy and tolerability of SAR3419, and of our ADC technology," commented John Lambert, PhD, EVP and Chief Scientific Officer. "The combination of SAR3419 and Rituxan was found to be well tolerated and to demonstrate activity in patients previously treated with Rituxan, even patients with primary refractory disease."

About this trial

Patients with CD19-positive and CD20-positive DLBCL relapsing or refractory after at least one standard treatment including Rituxan and who are not a candidate for or who already underwent transplant were eligible for enrollment in this Phase II trial. Refractory disease was defined as unresponsive to or progressing within 6 months of regimen completion.

Patients could receive a total of eight doses of CD19-targeting SAR3419 (at 55 mg/m2) and of CD20-targeting Rituxan (at 375 mg/m2), with the drugs administered weekly for four weeks and then every other week over eight weeks.

The primary study objective was ORR.

About SAR3419

This CD19-targeting ADC was developed by ImmunoGen and licensed to Sanofi as part of a broader collaboration between the companies. In addition to the trial reported today, Sanofi also has Phase II trials underway assessing SAR3419, used as a single agent, for the treatment of DLBCL and of B-cell acute lymphoblastic leukemia.

About ImmunoGen, Inc.

ImmunoGen, Inc. develops targeted anticancer therapeutics. The Company's ADC technology uses a tumor-targeting engineered antibody to deliver one of ImmunoGen's highly potent cancer-cell killing agents specifically to tumor cells; the Company has also developed antibodies with anticancer activity of their own. The most advanced compound with ImmunoGen's ADC technology is Roche's Kadcyla®, which is marketed in the US by Genentech and is also gaining approvals internationally. Additional compounds are in clinical testing by ImmunoGen and through the Company's partnerships with Amgen, Bayer HealthCare, Biotest and Sanofi. More information about ImmunoGen can be found at

Rituxan® and Kadcyla® are, respectively, registered trademarks of Biogen Idec and of Genentech, Inc., a member of the Roche Group.

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 SAR3419. A review of these risks can be found in ImmunoGen's Annual Report on Form 10-K for the fiscal year ended June 30, 2013 and other reports filed with the Securities and Exchange Commission.

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

Source: ImmunoGen, Inc.