ImmunoGen decides to stop IMGN901 Phase II SCLC study

ImmunoGen, Inc. (Nasdaq: IMGN), a biotechnology company that develops novel anticancer therapeutics using its antibody-drug conjugate (ADC) technology, announced today the decision to stop the IMGN901 Phase II SCLC study, following the recommendation of the trial's independent Data Monitoring Committee (DMC). ImmunoGen is in the process of updating study investigators and regulatory authorities. IMGN901 is a CD56-targeting ADC.

Based on analysis of available data, the DMC concluded that the addition of IMGN901 to etoposide/carboplatin (E/C) was unlikely to demonstrate a sufficient improvement in progression-free survival compared to E/C alone to justify continuation of the trial. As an imbalance in the rate of infection and infection-related deaths was noted between the arms, the DMC recommended that all patients discontinue IMGN901 treatment. Infection-related death is a recognized risk in SCLC trials, including trials with E/C. Among the 198 patients receiving IMGN901 as a single agent in early trials, there was one incidence of infection-related death; it was deemed possibly drug related.

"This is clearly a disappointing outcome, as there is a tremendous need for new treatment options for SCLC," commented Dr. Charles Morris, ImmunoGen EVP and Chief Development Officer. "We will be analyzing the findings to date in this trial as part of assessing potential next steps for IMGN901."

In the past 18 months, ImmunoGen has initiated clinical testing with three wholly owned ADC compounds: (1) IMGN853 for ovarian, endometrial, and other cancers that highly express folate receptor α; (2) IMGN529 for non-Hodgkin lymphoma; and (3) IMGN289 for lung, head and neck, and other cancers that highly express EGFR, as announced earlier today. Seven other ADCs with ImmunoGen technology are in the clinic through partnerships, the most advanced of which is the marketed product, Kadcyla^®.