Patients undergoing cord blood transplantation (CBT) can experience delayed hematopoietic recovery due to the typically smaller cell dose in cord blood units (CBUs), and therefore have a higher increase of post-transplant infections and transplant-related mortality. Co-infusion of a non-HLA matched, ex vivo expanded CBU in addition to an HLA-matched CBU in a transplant recipient is safe, according to research presented at ASH, and can result in significantly more faster hematopoietic recovery: a median of 19 days to neutrophil engraftment compared to historical controls of 25 days.
Researchers in this single-center study reported on 15 cord blood transplant recipients between 2010 and 2012 who were co-infused using this novel technique. The investigators prepared the ex vivo expand cord blood-derived progenitor cells using a Notch ligand-containing culture for 14 days. The product was then harvested and cryopreserved for use in the study.
All patients achieved neutrophil engraftment at a median of 19 days (range, 9-31), which the researchers noted was significantly faster than the 25 days (range, 14-45) observed in 41 recipients in a historical control group (p=0.01). The cumulative incidence of day-100 platelet recovery was significantly higher than that of a concurrent control group: 92% vs. 69%, respectively (p=0.005). No transplant-related mortality was observed throughout the study period, and at a median follow-up of 3.2 years, the 3-year disease-free survival was 86%.