ImmunoGen announced the presentation of encouraging clinical data for the Company’s IMGN388 anticancer compound at the 22nd EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics taking place in Berlin, Germany

WALTHAM, MA, USA | November 19, 2010 | ImmunoGen, Inc. (Nasdaq:IMGN – News), a biotechnology company that develops antibody-based anticancer products using its Targeted Antibody Payload (TAP) technology, today announced the presentation of encouraging clinical data for the Company’s IMGN388 anticancer compound at the 22nd EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics taking place in Berlin, Germany.

IMGN388, a TAP compound, is designed to target and kill cells that express its αv integrin target. This antigen is found on a number of types of solid tumors, including lung, breast and prostate cancers. It is also found on vascular cells in the process of forming new blood vessels, a process that needs to occur for any solid tumor to grow.

The poster presentation, entitled “A Phase I Study of IMGN388, an Antibody Drug Conjugate Targeting αv Integrin, in Patients with Solid Tumors,” reports findings from the trial’s dose-finding phase, which was designed to determine the maximum tolerated dose of the compound when administered once every three weeks. In this phase, IMGN388 was found to be well tolerated at doses up to and including 130 mg/m2 (3.5 mg/kg).

Initial evidence of activity also was reported, with four patients remaining on IMGN388 for 18 weeks or longer before disease progression. All but one of these patients was on IMGN388 longer than their last prior therapy. Two of these patients have received the compound for over 30 weeks and were still benefiting from treatment at the time of data analysis for the presentation.

“IMGN388 was well tolerated at doses at which evidence of anticancer activity was observed,” commented James O’Leary, MD, Vice President and Chief Medical Officer. “Based on the tolerability of the compound and its pharmacokinetic profile, our next step will be to evaluate IMGN388 when administered on a more frequent basis.”

About the Study

The data reported are from the first trial conducted with IMGN388. In the dose-finding phase of the study, new cohorts of patients received increasing doses of the compound to establish its maximum tolerated dose when administered once every three weeks. Patients enrolled in this phase were required to have advanced solid tumors, but it was not required that their tumor(s) express αv integrin. In the poster presented, thirty-eight patients had received one of ten different dose levels ranging from 5-160 mg/m².

Of the four patients remaining on IMGN388 for 18 weeks or longer, two had non-small cell lung cancer (NSCLC), one had prostate cancer, and one had a carcinoid tumor. One of the patients with NSCLC has been on study for over 32 weeks, and the patient with the carcinoid tumor has been on study for over 38 weeks. Both of these patients received IMGN388 at one of the higher doses evaluated (105 mg/m2).

The study protocol is now being amended to evaluate IMGN388 when administered weekly for two weeks (Day 1 and Day 8) in a 3-week cycle.

About ImmunoGen, Inc.

ImmunoGen, Inc. develops targeted anticancer therapeutics using the Company’s expertise in tumor biology, monoclonal antibodies and potent cancer-cell killing agents. 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 seven TAP compounds in the clinic, with a wealth of clinical data reported with the technology. ImmunoGen’s collaborative partners include Amgen, Bayer Schering Pharma, Biogen Idec, Biotest, Genentech (a member of the Roche Group), Novartis, and sanofi-aventis. The most advanced compound using ImmunoGen’s TAP technology, trastuzumab-DM1 (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.

SOURCE: ImmunoGen, Inc.