Thiotepa-busulfan-fludarabine compared to clofarabine-based conditioning for haploidentical transplant with posttransplant cyclophosphamide in patients with myeloid malignancies: a retrospective study from the SFGM-TC.

The study retrospectively compared two reduced-intensity conditioning (RIC) regimens, Clofarabine-Baltimore (CloB) and TBF (thiotepa-busulfan-fludarabine), in 297 adults undergoing haploidentical hematopoietic stem cell transplantation (haplo-HSCT) for myeloid malignancies.

No significant differences were found in overall survival (OS), progression-free survival (PFS), or GVHD-free relapse-free survival between the two regimens.

However, TBF was associated with a higher 2-year non-relapse mortality (NRM) but a lower relapse incidence compared to CloB.

Propensity-matched analysis showed that CloB had better 2-year OS (63% vs 44%), driven by significantly lower NRM.

Multivariate analysis confirmed CloB’s association with improved OS and TBF with increased NRM.

These findings suggest that CloB is a superior RIC regimen compared to TBF prior to haplo-HSCT.