Their phase 3 randomized trial included patients who were 50-70 years of age, or who had a Hematopoietic Cell Transplantation Comorbidity Index of 2 or greater. The final analysis included 551 patients (352 with AML and 199 with MDS).
The primary endpoint of the study was event-free survival at 2 years. That endpoint comprised relapse/progression of disease, graft failure, or death.
Patient enrollment was terminated early the MC-FludT.14/L study following an interim analysis that investigators said “clearly demonstrated” the noninferiority of the treosulfan/fludarabine regimen versus the reduced intensity busulfan/fludarabine regimen.
In the final analysis, event-free survival at 2 years was about 14.5 percentage points higher in the treosulfan group, at 65.7% versus 51.2% (P = .0000001), Dr. Beelen reported at the meeting.
A number of other secondary endpoints also favored treosulfan/fludarabine over busulfan, including overall survival (P = .0037), nonrelapse mortality (P = .0343), and survival free of chronic GvHD or relapse (P = .0030).