At the 17th Congress of the European Hematology Association in Amsterdam Professor Max Topp of the University of Wuerzberg in Germany presented results with a bispecific antibody for Acute Lymphoblastic Leukemia patients.
The Phase 2 dose-ranging study MT103-206 evaluated the efficacy, safety and tolerability of blinatumomab in adult patients with B-precursor Acute Lymphoblastic Leukemia who had relapsed following treatment with standard front-line chemotherapy or allogeneic stem cell transplant. Patients received blinatumomab for 28 days followed by two weeks off therapy over a six week treatment cycle, for up to five treatment cycles.
Patients received a continuous intravenous infusion of blinatumomab at an initial dose of five or 15 micrograms/m2 per day, escalating to 30 micrograms for the remainder of the treatment. The primary endpoint of the study was the rate of complete remission (CR) and complete remission with partial hematologic recovery (CRh*). Secondary endpoints included molecular response rate, duration of response and overall survival. All 36 patients were evaluable for efficacy and safety.
Twenty-six of the 36 patients (72%) treated with blinatumomab across all of the tested doses and schedules achieved a CR/CRh*. All but two patients achieved a molecular response, meaning there was no evidence of leukemic cells by polymerase chain reaction. The most common adverse events were pyrexia, headache and tremor. Medically important safety events were reversible cytokine release syndrome and CNS adverse events.
At the time of the analysis, median survival was 9.0 (8.2, 15.8) months with a median follow-up period of 10.7 months. The median duration of response in the 26 patients who responded to treatment was 8.9 months.