Excellent Outcomes of Allogeneic Hematopoietic Stem Cell Transplantation in Patients with Paroxysmal Nocturnal Hemoglobinuria: A Single-Center Study

We analyzed the outcomes of 44 patients with paroxysmal nocturnal hemoglobinuria (PNH) who received allogeneic hematopoietic stem cell transplantation (allo-HSCT) (haploidentical [haplo]-donors, 25; matched sibling donors [MSDs], 15; and matched unrelated donors, 4) between July 2007 and May 2018. All patients achieved successful donor engraftment. The median time was 12 days (range, 7 to 26) for myeloid engraftment and 13 days (range, 11 to 75) for platelets. The cumulative incidences were 15.91% and 2.27% for grades II to IV and grades Ill to IV acute graft-versus-host disease (GVHD), respectively, with a median follow-up time of 36 months (range, 4 to 132). The cumulative incidences were 26.73% for chronic GVHD and 9.70% for moderate to severe chronic GVHD. No patients relapsed. The probabilities of 3-year overall survival (OS) and GVHD-free, failure-free survival (GFFS) were 90.4 +/- 4.6% and 85.6 +/- 5.4%, respectively. The 3-year OS rates of the haplo-donor and MSD groups were 86.5 +/- 7.3% versus 93.3 +/- 6.4% (P=.520). The 3-year GFFS rates of the haplo-donor and MSD groups were 78.3 +/- 8.6% versus 92.9 +/- 6.9% (P=.250). The preliminary results indicated that allo-HSCT is a feasible option for patients with PNH; however, this should not be considered as a first-choice therapy, because the results seemed to only suggest rather than confirm that haplo-HSCT and MSD-HSCT exerted similar therapeutic efficacies. (C) 2019 American Society for Blood and Marrow Transplantation.