Factors Predictive of Response to Venetoclax Treatment in AML
Posted: Friday, July 31, 2020
The BCL2 inhibitor venetoclax has produced high rates of complete remission and complete remission with incomplete count recovery in patients with acute myeloid leukemia (AML) when combined with hypomethylating agents such as azacitidine or decitabine, or with low-dose cytarabine. Although many patients achieve rapid responses to venetoclax combination treatments, some require multiple cycles of therapy. Brian Andrew Jonas, MD, PhD, of the University of California Davis Comprehensive Cancer Center, Sacramento, and colleagues
investigated patient characteristics associated with response time and likelihood of response to venetoclax combination therapy in patients newly diagnosed with AML. Their results were presented during the ASCO20 Virtual Scientific Program (Abstract 7531).
Two studies were pooled in this analysis. A total of 197 patients, 60 years of age or older, with newly diagnosed AML received label-consistent doses of venetoclax. Patients in the phase Ib study (n = 115) received 400 mg of venetoclax plus azacitidine or 400 mg of venetoclax plus decitabine. Those enrolled in the phase I/II trial (n = 82) received 600 mg of venetoclax plus low-dose cytarabine. Baseline characteristics were comparable between the two studies and included AML type, cytogenetic risk, and genetic mutations.
The two most significant factors contributing to whether or not a patient achieved a response were achievement of a morphologic leukemia-free state within the first two cycles of treatment and AML cancer type. Just 18% of patients with secondary AML who did not achieve a morphologic leukemia-free state experienced complete remission or complete remission with incomplete count recovery in a later cycle. More than one-third of patients (n = 44) achieved a response with at least two treatment cycles, and 36% (n = 70) did not respond.
“Prior to discontinuing therapy for nonresponders, it is critical to assess key predictive patient characteristics,” explained the researchers.
Disclosure: The study authors’ disclosure information can be found at coi.asco.org.