Biol Blood Marrow Transplant. 2017 Jul 3. pii: S1083-8791(17)30554-2. doi: 10.1016/j.bbmt.2017.06.023. [Epub ahead of print]

Umbilical Cord Blood Transplantation in Children with Acute Leukemia: Impact of Conditioning on Transplant Outcomes.

Eapen M¹, Kurtzberg J², Zhang MJ³, Hattersely G³, Fei M³, Mendizabal A⁴, Chan KW⁵, De Oliveira S⁶, Schultz KR⁷, Wall D⁸, Horowitz MM³, Wagner JE⁹.

Abstract

The Blood and Marrow Transplant Clinical Trials Network (BMT CTN 0501) randomized children with hematologic malignancy to one or two cord blood unit (UCB) transplantation between 2006 and 2012. While the trial concluded that survival was similar regardless of number of units infused, survival was better than previously reported. This prompted a comparison of survival of trial versus non-trial patients to determine the generalizability of trial results and whether survival was better because of the trial treatment regimen. During the trial period, 396 recipients of a single UCB unit met trial eligibility but were not enrolled. Trial patients (n=100) received total body irradiation (TBI) 1320 cGy, cyclophosphamide 120 mg/kg, and fludarabine 75 mg/m² (TCF). Non-trial patients either received the same regimen (N=62; non-trial TCF) or alternative regimens (N=334; non-trial regimens). Five-year survival between trial and non-trial patients conditioned with TCF was similar (70% vs. 62%). However, 5-year survival was significantly lower with non-trial TBI-containing (47% [HR 1.97, p=0.001]) and chemotherapy only regimens (49% [HR 1.87, p=0.007]). The results of BMT CTN 0501 appear generalizable to the population of trial eligible patients. The survival difference between the trial-specified regimen and other regimens indicate the importance of conditioning regimen for UCB transplantation.