NEW YORK – Bristol Myers Squibb announced on Tuesday that its acute myeloid leukemia drug enasidenib (Idhifa) combined with best supportive care failed to significantly extend overall survival compared to conventional regimens in relapsed and refractory patients with an IDH2 mutation.
In the Phase III IDHENTIFY trial, relapsed and refractory, IDH2-mutated AML patients were randomized to receive either enasidenib plus best supportive care or conventional treatments, such as best supportive care, best supportive care plus azacitidine, or best supportive care plus low-dose or intermediate-dose cytarabine.
The primary endpoint is overall survival. Researchers are also looking at overall response rate, duration of response, and event-free survival as secondary endpoints. No new safety signals were identified in the Phase III trial, though BMS is still conducting a full evaluation of the data and will present the results at an upcoming medical meeting.
Three years ago, the US Food and Drug Administration granted BMS full approval for enasidenib as a treatment for relapsed or refractory AML characterized by an IDH2 mutation. The approval was based on data from a single-arm study involving around 200 patients.
After at least six months of treatment, 19 percent of patients in the trial experienced complete remission, defined as no evidence of disease and full recovery of blood counts, for a median of 8.2 months; 4 percent had no evidence of disease and partial recovery of blood counts for a median of 9.6 months. Additionally, 34 percent of 157 patients who needed blood transfusions at the start of the study, didn't need transfusions after enasidenib treatment.
Based on this data back in 2017, Richard Pazdur, director of FDA's Oncology Center of Excellence, said in a statement that enasidenib fills an unmet need in IDH2-mutated relapsed or refractory AML. Around 20 percent of AML patients harbor an IDH2 mutation.
"While we are disappointed by the outcome of the IDHENTIFY study, we remain confident in Idhifa's established role as a treatment option for patients with relapsed or refractory AML with an IDH2 mutation," Noah Berkowitz, senior VP of global clinical development within BMS' hematology division, said in a statement. "AML is one of the most difficult-to-treat blood cancers, and we're committed to furthering our research and improving on the standards of care for patients living with this aggressive disease."