A Multi-Institutional Retrospective Data Analysis of Hematopoietic Cell Transplantation for Less Severe Sickle Cell Disease

Abstract

Methods: Pediatric patients (<21 years old, n1⁄434) on a research protocol between 4/2006 and 6/2014 receiving myeloablative conditioning (FLU/CY/13.2 Gy TBI) with or without expanded CB HSPC (fresh or cryopreserved) were included. Duration of initial hospitalization, use of opiate pain medications (by continuous infusion or PCA), and use of TPN were determined for each patient. All blood stream infections occurring during initial hospitalization were also recorded. Statistical comparisons between groups were made with two-tailed, unpaired t-tests. Results: 11 patients received expanded CBHSPC in addition to 1-2 unmanipulated CB units while a concurrent cohort of 23 patients received the same conditioning regimen without expanded cell infusion. The mean time to neutrophil count of 500/mlwas16.5v.22.1days inpatients receivingexpandedcells or not, respectively (p1⁄40.026). The mean duration of initial hospitalization was 43.2 v. 55.6 days (p1⁄40.05) (Fig. 1), mean duration for continuous opiate medications 9.7 v. 18.1 days (p1⁄40.07), and mean time receiving TPN was 20.7 v. 30.1 days (p1⁄40.06) (Fig. 2). Although not statistically significant, bacterial blood stream infections were identified during their initial hospitalization in 3 patients receiving expanded CB HSPC compared to 10 in the standard treatment group. Conclusions: In addition to reduce time to ANC recovery, these results suggest that administration of expanded CB HSPC may significantly reduce initial hospitalization and may also reduce utilization of pain medications and nutritional support in the pediatric population receiving CBT. Thus, this cellular therapy has the potential to decrease the risk of morbidity and mortality post-CBT by reducing regimen related toxicities that directly result from delayed hematopoietic recovery.