Real World Study on the Best CPX‐351 Treatment Duration and Timing for Allogeneic Stem Cell Transplantation

In the registration clinical trial 301 (NCT01696084), CPX‐351 has shown to be superior to conventional 3 + 7 in secondary AML (s‐AML). However, the optimal duration of treatment, the best timing for allogeneic stem cell transplantation (allo‐HSCT), and the activity of CPX‐351 in specific s‐AML subgroups are unclear. To evaluate these aspects, a total of 513 s‐AML patients (median age 65.6 years, 19–79) treated with CPX‐351 were retrospectively analyzed. Complete remission (CR) rate after induction was 297/513 (58%), increasing to 340/513 (66%) after cycle 2. Among the 340 responding patients, 118 (34.7%), 137 (40.3%), and 85 (25%) received none, one, or two consolidation cycles of CPX‐351, respectively. Overall, 230/513 patients (48.8%) received allo‐HSCT. Median follow up was 23.66 months and median overall survival (OS) was 16.23 months. Patients with mutated NPM 1 or with ELN 2017 favorable risk ( p < 0.05) had a significantly longer OS ( p < 0.05). In a landmark analysis, receiving allo‐HSCT was associated with a longer survival (Median OS not reached vs. 16.3 months for patients receiving or not receiving allo‐HSCT, p < 0.05). Completion of all allowed CPX‐351 cycles was beneficial only in patients not proceeding to transplant ( p < 0.05), whereas in transplanted patients additional CPX‐351 cycles did not improve outcome. Our analysis suggests that also s‐AML patients with NPM1 mutations and those belonging to the ELN 2017 favorable risk category benefit from CPX‐351. In eligible patients, allo‐HSCT should be performed as soon as a CR is achieved, whereas patients not undergoing transplant benefit from a complete CPX‐351 schedule.