In patients with relapsed/refractory (R/R) B-cell acute lymphoblastic leukaemia (B-ALL), allogeneic haematopoietic stem cell transplantation (HSCT) after blinatumomab is feasible and potentially safe, according to data from a nationwide registry in Japan.

Data from 181 patients treated at 76 institutions were retrospectively analyzed. Among survivors, median follow-up duration post-HSCT was 1,663 days. At HSCT, median age was 29 years, 59.1 percent were male, and 81.2 percent were not in first complete remission. HSCT was the first transplantation for 74 percent of patients. [Shinohara A, et al, EHA 2026, abstract PS1504]

At 3 years, rates of leukaemia-free survival and overall survival (OS) were 41.8 and 57.3 percent, respectively, while cumulative incidence of relapse and nonrelapse mortality (NRM) was 38.6 and 19.5 percent, respectively.

Cumulative incidence of grade 2–4 acute graft versus host disease (GVHD) by day 100 was 40.5 percent, while that of chronic and extensive chronic GVHD at 1 year was 12.9 and 7.8 percent, respectively. Post-transplant relapse occurred in 38.7 percent of patients.

One-year cumulative incidence of sinusoidal obstruction syndrome (SOS) was 11.7 percent. According to the researchers, 31.5 percent of patients had prior exposure to inotuzumab ozogamicin, which may have contributed to the notable incidence of SOS.

“HSCT following blinatomumab for R/R B-ALL demonstrated acceptable OS. Although this population was heavily pretreated, NRM was lower than expected based on previous reports, suggesting that HSCT after blinatomumab is feasible and potentially safe,” they concluded.

HSCT after blinatumomab feasible in Asians with R/R B-ALL