Imatinib vs Dasatinib Prophylaxis Among Patients With Philadelphia-Positive ALL Post-Transplantation

Findings from a Retrospective Cohort Study

Findings from a retrospective cohort study published in Cancer indicated that imatinib prophylaxis demonstrated long-term outcomes comparable to dasatinib among patients with Philadelphia-positive (Ph-positive) acute lymphoblastic leukemia (ALL) after undergoing allogeneic stem cell transplantation (ASCT) at first complete remission.  

According to prior research, the introduction of tyrosine kinase inhibitors and stem cell transplantation has significantly improved survival outcomes among this patient population. However, “prevention of relapse after transplantation remains a concern,” Fangshu Guan, MD, Zhejiang University, Hangzhou, Zhejiang, China, and coauthors explained. The goal of this study was to analyze the potential difference in the impact of tyrosine kinase inhibitor prophylaxis with imatinib versus dasatinib on long-term patient outcomes post-transplantation. 

A total of 141 patients with Ph-positive ALL who had previously undergone ASCT at the first complete remission and received tyrosine kinase inhibitor prophylaxis post-ASCT were enrolled in this study and assigned to 1 of 2 cohorts. The first cohort consisted of 91 patients who received imatinib, and the second cohort consisted of 50 patients who received dasatinib. 

After a median follow-up of 50.6 months, results indicated that the 5-year cumulative incidence of relapse was 16.1% in the imatinib cohort versus 12.5% in the dasatinib cohort. The 5-year non-relapse mortality rate was 5.2% in the imatinib cohort and 9.8% in the dasatinib cohort. The 5-year overall survival rate was 86.5% in the imatinib cohort and 77.6% in the dasatinib cohort. The study authors noted that there were no statistical differences between these data points of the 2 cohorts.

Regarding safety, the cumulative incidence of mild chronic graft-versus-host disease was higher among patients who received dasatinib. The most prevalent adverse event to occur was neutropenia. Gastrointestinal bleeding was observed at a higher incidence in the dasatinib cohort (25.5%) than in the imatinib cohort (2.3%). Similarly, gastrointestinal reaction also occurred at a higher incidence in the dasatinib cohort (48.9%) than in the imatinib cohort (31.4%). Fewer patients in the dasatinib cohort were treated on schedule than in the imatinib cohort, with the main reason for protocol violation being drug intolerance. 

Based on these findings, Guan and the study authors concluded, “For patients with Ph+ ALL undergoing allo-HSCT in CR1, imatinib prophylaxis achieved long-term outcomes similar to those of dasatinib.”

“Furthermore, choosing imatinib as a maintenance therapy resulted in a longer exposure time, primarily because of its better tolerance,” they added. 

Source: 

Guan F, Yang L, Chen Y, et al. 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. Cancer. Published online: February 5, 2024. doi: 10.1002/cncr.35232