Xencor Presents Updated Data from the Phase 1 Study of Vibecotamab in Acute Myeloid Leukemia at the 2020 ASH Annual Meeting
Xencor, Inc. (NASDAQ:XNCR), a clinical-stage biopharmaceutical company developing engineered monoclonal antibodies for the treatment of cancer and autoimmune disease, today announced updated data from its ongoing Phase 1 dose-escalation study of vibecotamab (XmAb14045), a CD123 x CD3 bispecific antibody, in patients with relapsed or refractory acute myeloid leukemia (AML). The data were presented in an oral session at the 62nd American Society of Hematology (ASH) Annual Meeting by Farhad Ravandi, M.D., Professor of Medicine and Chief of the Section of Acute Myeloid Leukemia in the Department of Leukemia at the University of Texas - MD Anderson Cancer Center.
"Vibecotamab has meaningful clinical activity in relapsed AML, and responses appear to be associated with lower baseline disease burden, indicated by patients with lower blast percentages and lower PD1 expression on CD8+ and CD4+ T cells. This suggests possible strategies to select patients most likely to respond," said Dr. Ravandi. "Responses including CRs and CRis have been durable, lasting many months, in several patients."
"Additionally, we continue to observe that vibecotamab's primary toxicity, CRS, is generally mild-to-moderate in severity when observed, and our mitigation strategy, which includes a combination of dose-modifying measures, has been effective in limiting its severity," said Allen Yang, M.D., Ph.D., senior vice president and chief medical officer. "With a manageable profile and encouraging potential in certain patient populations, such as myelodysplastic syndromes and AML with minimal residual disease, we are now planning our next steps to develop vibecotamab for these patients, along with our partner Novartis."
Key Highlights from the Presentation
At data cut off on October 28, 2020, 112 patients with relapsed or refractory AML had received vibecotamab. Patients were a median of 64 years old and were heavily pretreated, having had a median of three prior therapies and 30% (n=34) with a history of allogeneic hematopoietic stem cell transplantation. 86% of patients (n=96) were refractory to their last therapy, and 62% (n=69) were categorized as adverse risk at diagnosis by the European LeukemiaNet (ELN 2017) system. The study is ongoing, and additional patients are being enrolled.