Dr. Milner on Hematopoietic Stem Cell Transplant in Aplastic Anemia

Jordan B. Milner, MD, clinical assistant professor, Department of Pediatric Hematology Oncology, the University of Florida College of Medicine, discusses findings from a study evaluating the use of hematopoietic stem cell transplant (HCT) up front or as salvage therapy after unsuccessful immunosuppressive therapy in pediatric patients with severe aplastic anemia.

This study pooled data from the 5 transplant programs in the Florida Pediatric BMT and Cell Therapy Consortium and included patients who had received HCT for severe aplastic anemia from 2010 to 2020. This analysis included 52 pediatric patients, 24 who received pre-transplant immunosuppressive therapy, 27 who did not receive immunosuppressive therapy, and 1 with missing data. In the entire study population, the donor sources included matched related (n = 24), haploidentical (n = 13), matched unrelated (n = 7), mismatched unrelated (n = 5), and cord blood (n = 3).

In all patients, the 2-year overall survival (OS) rate was 81%, including 2-year rates of 70% and 90.5% in those who did and did not receive immunosuppressive therapy, respectively. This study demonstrated improved outcomes in patients who did not receive immunosuppressive therapy and instead received HCT up front and in those who underwent HCT within 12 months of severe aplastic anemia diagnosis, regardless of donor type, Milner says. The 2-year OS rate was 90% in the 35 patients who received HCT within 12 months of diagnosis vs 63% in the 17 patients who received HCT more than 12 months after their diagnosis.

Additionally, of the 13 patients who received haploidentical HCT with post-transplant cyclophosphamide (PTCy), the 2-year OS rates were 80% in those who also received prior immunosuppressive therapy (n = 10) and 100% in those who did not receive immunosuppressive therapy (n = 3). These findings support the safety and feasibility of haploidentical transplants in pediatric patients using PTCy techniques, Milner concludes.