Abstract

Summary Mesenchymal stromal cell ( MSC ) infusions have been reported to be effective in patients with steroid‐refractory, acute graft‐versus‐host disease (a G v HD ) but comprehensive data on paediatric patients are limited. We retrospectively analysed a cohort of 37 children (aged 3 months‐17 years) treated with MSC s for steroid‐refractory grade III – IV a G v HD . All patients but three received multiple MSC infusions. Complete response ( CR ) was observed in 24 children (65%), while 13 children had either partial ( n = 8) or no response ( n = 5). Cumulative incidence of transplantation‐related mortality ( TRM ) in patients who did or did not achieve CR was 17% and 69%, respectively ( P = 0·001). After a median follow‐up of 2·9 years, overall survival ( OS ) was 37%; it was 65% vs. 0% in patients who did or did not achieve CR , respectively ( P = 0·001). The median time from starting steroids for G v HD treatment to first MSC infusion was 13 d (range 5–85). Children treated between 5 and 12 d after steroid initiation showed a trend for better OS (56%) and lower TRM (17%) as compared with patients receiving MSC s 13–85 d after steroids (25% and 53%, respectively; P = 0·22 and 0·06, respectively). Multiple MSC infusions are safe and effective for children with steroid‐refractory a G v HD , especially when employed early in the disease course.