Amgen announced updated results from a Phase 2 study that showed treatment with blinatumomab (AMG 103) helped achieve a high-rate of complete response (CR) in 72% of adult patients with relapsed or refractory B-precursor acute lymphoblastic leukemia (ALL) treated in the study.
Blinatumomab is the first of a new class of agents called bi-specific T cell engagers (BiTE) antibodies, designed to harness the body’s cell-destroying T cells to kill cancer cells. Blinatumomab targets cells expressing CD19, a protein found on the surface of B-cell derived leukemias and lymphomas, such as ALL.
Full results of the study will be presented at the 48th Annual Meeting of the American Society of Clinical Oncology (ASCO) on June 4.
In this Phase 2 single-arm dose-ranging trial, 26 of the 36 patients treated with blinatumomab across all of the tested doses and schedules achieved a complete response with partial hematologic recovery. All but two patients achieved a molecular response, meaning there was no evidence of leukemic cells by polymerase chain reaction. No treatment related deaths or serious adverse events were reported in the study.
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. In the group of patients who received the selected dose, median survival was 8.5 months. The median duration of response in the 26 patients who responded to treatment was 8.9 months.
“For these patients with limited treatment options, the remission rate observed in the trial is a vast improvement over the current standard of care,” said Max Topp, department of internal medicine II, University of Wuerzburg and chair of the study. “These results also represent significant progress in our research of immunotherapies; a new approach to fighting cancer that we believe could make a real difference for patients.”
For patients who received the selected dose and schedule, the most common adverse events were grade one or two and included pyrexia (70%), headache (39%), tremor (30%) and fatigue (30%). These were most frequently seen at the onset of treatment in cycle one. Reversible central nervous system events led to treatment interruptions in six patients with two patients permanently discontinuing treatment. Cytokine release syndrome led to treatment interruption in two patients.
In addition to the results from this study, data from studies of 12 Amgen investigational molecules and marketed products will be presented at the ASCO Annual Meeting. These include results from studies of the immunotherapy talimogene laherparepvec, pipeline molecules such as rilotumumab (AMG 102) and AMG 386 and marketed products.
Release Date: May 16, 2012