Micromet’ s blitumab meets study goals
Martinsried/Bethesda – Micromets bifunctional monoclonal antibody drug blinatumomab (MT103) has met its study goals in two independent clinical trails. In a Phase I dose escalation study in 52 adult patients with relapsed non-Hodgkin's lymphoma (NHL), the BITE antibody which activates T- killer cells against tumour cells, achieved an objective response rate of 100% (8 of 8 patients) at a once daily dosage of 60µg/sqm. The median response duration was 21 months. However, in a sub-group of patients with an identified prognostic factor, Blinatumomab induced neurologic events that led to study discontinuation. This was avoided when starting with a low dosage of 15µg/mg ("step-dose approach"), with no grade 3 or higher neurological events occurring and five objective responses being achieved among the six patients treated with MT103. In a Phase 2 trial in adult patients with minimal residual disease (MRD) in positive acute lymphoblastic leukemia (ALL), Blinatumomab achieved 1st primary endpoint of MRD response. Of 20 evaluable patients, who received 15µg/sqm, 80% (16 out of 20) achieved a complete MRD response. Key secondary endpoints included time to hematological relapse, time to molecular relapse and overall incidence and severity of adverse events. Based on the results reported to date in ALL, Micromet plans to initiate a pivotal, non-randomized, multi-center trial intended to confirm the efficacy and safety of blinatumomab in adult patients with B precursor ALL with minimal residual disease after treatment with front-line chemotherapy. Patients will receive 15 micrograms per meter squared per day of blinatumomab for 28 days followed by two weeks off therapy over a six week treatment cycle. The primary endpoint of the study is MRD response as assessed by PCR analysis. The key secondary endpoint is time to hematological relapse (for non-transplanted patients). The Company currently plans to enroll up to 130 evaluable patients at approximately 70 leading cancer centers in Europe and the U.S.