Immunogen at ASH 2007 – part I (IMGN901)
Wednesday, December 26th, 2007At ASH (American Society of Hematology), Immunogen (IMGN) and its partners presented data on several projects including IMGN901(formerly known as HuN901) for Multiple Myeloma and AVE9633 for AML (Acute Myelogenous Leukemia) .
The company presented updated results from its phase I dose escalation study in Multiple Myeloma patients who have failed prior treatments. IMGN901 was administered weekly for 2 consecutive weeks in a 3-week cycle, and the company reported results from 12 patients in 4 cohorts of 3. The evaluated doses were 40 mg/m2/week, 60 mg/m2/week, 75 mg/m2/week, and 90 mg/m2/week. Immunogen had previously published results for the two lower doses, which included one partial response (PR) and 2 stable disease (SD) in the 60 mg/m2/week cohort. In its ASH presentation, the company revealed that among the 6 patients who received the 2 higher doses (75 and 90 mg/m2), there was also one partial response in a patient at the 90 mg/m2/week cohort, although this patient had to drop out of the trial due to unrelated issues. Of note, the patient who responded at 60 mg/m2 is still on the study, after more than 10 months.
I must admit I expected results to be somewhat better, based on management’s remarks in several investor conferences. I wrongly concluded that if a company gets a partial response in 1 out of 3 patients who were dosed at 60 mg/m2, and claims to be very excited about the 2 higher doses, there would be at least one partial response in each cohort to generate a response rate of 33%. Nevertheless, these results are quite positive for two reasons. First, all patients who participated in this trial were heavily pretreated patients, who had already received more than four prior therapies. Second, IMGN901 demonstrated excellent safety profile as no severe side effects were documented. This means that additional patients can be recruited and receive higher doses, that might be more effective.
