ImmunoGen's SAR3419 holds hope for B-cell non-Hodgkin’s lymphoma

ImmunoGen, Inc. (Nasdaq: IMGN), a biopharmaceutical company that develops targeted anticancer therapeutics, today announced the presentation of encouraging initial clinical findings with SAR3419 at the American Society of Hematology (ASH) 51^st Annual Meeting and Exposition. Among the findings reported were responses to SAR3419 – administered as a single agent – among patients with B-cell non-Hodgkin's lymphoma that is refractory to treatment with rituximab (Rituxan®).

SAR3419 is an investigational compound designed to target and kill cancer cells that express the protein, CD19, on their surface. The compound is in development by sanofi-aventis for the treatment of relapsed/refractory CD19-expressing non-Hodgkin’s lymphoma and other B-cell malignancies. ImmunoGen created SAR3419 using its Targeted Antibody Payload (TAP) technology and licensed it to sanofi-aventis as part of a broader collaboration.

The study found that 17 of 27 (63%) patients who were response-evaluable at the time of data cut-off for presentation experienced a reduction in tumor size (7% to 86% reduction). These included 7 of 14 (50%) patients who had disease that was refractory to treatment with rituximab.

Five patients had an objective response, all of whom received SAR3419 at its maximum tolerated dose (MTD) or the next highest or lowest dose. Among these responders was a patient with rituximab-refractory disease. All but one of these five patients reached the best response either during the last treatment cycle allowed under the study protocol (cycle 6) or after their last dose of SAR3419. This is consistent with the observation that the best response to treatment typically occurred after a patient had received several doses of SAR3419.

A primary endpoint of the study was to establish the MTD of SAR3419 when administered once every three weeks. This was determined to be 160 mg/m². Additional patients will receive SAR3419 at this dose to gain more information on the tolerability and activity of the compound when administered at its MTD. A Phase I study also is underway to assess weekly dosing of SAR3419.

“These initial findings support that SAR3419 offers potential for the treatment of B-cell non-Hodgkin’s lymphoma, including rituximab-refractory disease,” commented John Lambert, PhD, Executive Vice President and Chief Scientific Officer, ImmunoGen. “SAR3419 has demonstrated evidence of activity at doses that were well tolerated. Of particular note, the compound wasn’t associated with toxicities that would limit its ability to be evaluated as part of a combination regimen in future studies, if desired. We look forward to seeing the findings from the expansion phase of this trial as well as from the weekly-dosing study.”

SOURCE ImmunoGen, Inc.