New findings from Micromet's blinatumomab phase 1 trial on DLBCL

New findings from a phase 1 trial presented yesterday at the 53^rd Annual American Society of Hematology (ASH) Annual Meeting demonstrate Micromet's blinatumomab induces durable responses in patients with extensively pre-treated diffuse large B cell lymphoma (DLBCL). Blinatumomab is the first of a new class of agents called BiTE® antibodies, designed to harness the body's T cells to kill cancer cells.

Data presented at the meeting focused on a cohort of 13 patients with DLBCL, of which 11 received the target dose and were evaluable for response. Of these 11 patients, 6 (55%) achieved an objective response following treatment with blinatumomab. 4 of 11 patients (38%) achieved a complete response. Patients were treated with a single course of blinatumomab induction therapy for up to eight weeks. As of October 2011, 5 of 6 patients had ongoing responses for up to 16.6 months. The median duration of response had not been reached with a median observation time of 7.1 months.

All patients enrolled in this study had received prior rituximab-containing regimens. Most had received three or more prior lines of therapy, including 8 of 13 patients with prior autologous stem cell transplant.

"The level of activity observed with a single agent in this heavily pre-treated patient population is unusual," said Andreas Viardot, M.D., Department of Medicine III, University of Ulm. "We look forward to further exploring blinatumomab's activity in patients with relapsed diffuse large B cell lymphoma."

The most common clinical adverse events were grade 1 or 2 and included flu-like symptoms, pyrexia, headache, and fatigue. These were most frequently seen at the onset of treatment. The clinically most relevant adverse events were fully reversible central nervous system (CNS) events. A key objective of this study was to optimize the type and timing of steroid administration to mitigate the risk of developing CNS adverse events. Notably, no discontinuations due to CNS events were observed in the five patients who received an optimized steroid schedule including dexamethasone administration starting 12 hours before the start of blinatumomab infusion.

"With an improved steroid pre-medication schedule, we have successfully treated patients with relapsed diffuse large B cell lymphoma at the blinatumomab target dose," said Jan Fagerberg, M.D., Ph.D., Micromet's Senior Vice President and Chief Medical Officer. "We plan to initiate in 2012 a phase 2 trial in patients with diffuse large B cell lymphoma."

Source: Micromet