The tyrosine kinase inhibitor ponatinib and monoclonal antibody blinatumomab—which targets CD19 on leukemia cells—are highly effective as monotherapies for patients with Philadelphia chromosome–positive (Ph+) acute lymphoblastic leukemia (ALL). The combination of the two therapies may provide an alternative to chemotherapy and stem cell transplant (SCT) without the associated risks and side effects. In a phase II trial presented by Nicholas Short, MD, Assistant Professor in the Department of Leukemia at The University of Texas MD Anderson Cancer Center, at the European Hematology Association (EHA) 2022 Congress (Abstract S114), researchers evaluated the safety and efficacy of the chemotherapy-free combination of ponatinib plus blinatumomab in 55 patients with either newly diagnosed or relapsed or refractory Ph+ ALL and patients with chronic myeloid leukemia in lymphoid blast phase (CML-LBP).
Nicholas Short, MD
Results
Complete molecular response was seen in 96% of newly diagnosed patients with Ph+ ALL, 92% of patients with relapsed or refractory Ph+ ALL, and 83% of patients with CML-LBP. For newly diagnosed patients with Ph+ ALL, the 2-year event-free survival rate and overall survival rate each were 93%. No relapses have been observed, and SCT was not needed in first remission.
The treatment was well tolerated, with most toxicities being grade 1 or 2, suggesting this combination is safe and effective for patients with Ph+ ALL. The promising outcomes in newly diagnosed patients with Ph+ ALL suggest that this regimen may be able to eliminate the need for chemotherapy and SCT for these patients.
Disclosure: For full disclosures of the study authors, visit library.ehaweb.org.
