Comparison of long‐term outcomes between imatinib and dasatinib prophylaxis after allogeneic stem cell transplantation in patients with Philadelphia‐positive acute lymphoblastic leukemia: A multicenter retrospective study

Abstract Background Although the prognosis of Philadelphia‐positive acute lymphoblastic leukemia (Ph+ ALL) has improved with the introduction of tyrosine kinase inhibitors (TKIs) and stem cell transplantation, prevention of relapse after transplantation remains a concern. The aim of this study was to compare the impact of TKI prophylaxis with imatinib and dasatinib on long‐term outcomes after transplantation. Methods Patients with Ph+ ALL who underwent allogeneic hematopoietic stem cell transplantation (allo‐HSCT) at first complete remission (CR1) and received TKI prophylaxis after allo‐HSCT were included in this retrospective analysis. Two cohorts were established based on the choice of TKI prophylaxis: the imatinib (Ima) and dasatinib (Das) cohorts. The survival and safety outcomes of these cohorts were compared. Results Ninety‐one patients in the Ima cohort and 50 in the Das cohort were included. After a median follow‐up of 50.6 months, the 5‐year cumulative incidence of relapse, nonrelapse mortality rate, and overall survival in the Ima and Das cohorts were 16.1% and 12.5%, 5.2% and 9.8%, and 86.5% and 77.6%, respectively, with no statistical differences. The cumulative incidence of mild chronic graft‐versus‐host disease was higher in the Das cohort. The most common adverse event was neutropenia (64.7% vs. 69.5%). The Das cohort had a higher incidence of gastrointestinal bleeding (25.5% vs. 2.3%) and gastrointestinal reaction (48.9% vs. 31.4%) than the Ima cohort. The proportion of patients treated on schedule was significantly lower in the Das cohort than in the Ima cohort, and drug intolerance was the main reason for protocol violation. Conclusions For patients with Ph+ ALL undergoing allo‐HSCT in CR1, imatinib prophylaxis achieved long‐term outcomes similar to those of dasatinib.