Autologous transplant versus matched sibling donor transplant in intermediate-risk AML in CR1 with no detectable MRD:...

Retrospective studies suggested that autologous stem cell transplantation (auto-SCT) might achieve comparable or even better outcomes compared with allogeneic SCT for patients with genetic intermediate-risk acute myeloid leukemia (IR-AML) and no detectable measurable residual disease (MRD-). However, prospective studies are lacking comparing auto-SCT and matched sibling donor SCT (MSD-SCT).

We initiated a biological assignment comparative study at fourteen institutions in China. Patients with newly diagnosed de novo IR-AML and MRD- within 3 cycles of intensive chemotherapy were eligible for the study if they were 14 to 60 years old and received auto-SCT or MSD-SCT. Patients were assigned to auto-SCT or MSD-SCT based on donor availability. The primary endpoint was the 3-year disease-free survival (DFS). The trial was registered with Clinicaltrials.gov, NCT03620955 and completed.

Between November 15, 2018, and March 31, 2022, 708 patients were screened and 518 eligible for analysis, including 259 in the auto-SCT and 259 in the MSD-SCT groups. With a median follow-up time of 55.2 (IQR 47.4-65.2) months, the 3-year DFS was 82.2% (95% CI 77.0-86.4) and 85.7% (95% CI 80.8-89.4) in auto-SCT and MSD-SCT respectively (HR, 1.24 [95% CI, 0.81-1.91]; p=.32). The treatment-adjusted difference was 3.2% (95% CI, - 3.1 to 9.4; p<.001). Because the upper bound of the 95% CI (9.4) did not exceed 10%, noninferiority was shown. The 3-year overall survival (OS) was 90.7% (95% CI 86.5-93.7) and 87.6% (95% CI 83.0-91.1) respectively (HR, 0.78 [95% CI, 0.47-1.30]; p=.34). In subgroup analyses, auto-SCT achieved similar DFS and OS to MSD-SCT among patients who reached MRD- in the first 2 cycles of chemotherapy, while auto-SCT had inferior DFS but similar OS for patients who achieved MRD- after 3 cycles.

Auto-SCT achieved non-inferior DFS and similar OS compared with MSD-SCT, suggesting that auto-SCT is a viable and preferable first-line choice for IR-AML patients achieving MRD- within 3 cycles of chemotherapy, particularly those who reached MRD- in the first 2 cycles.