LAUSR

Allogeneic haematopoietic stem cell transplantation (alloHSCT) might be used in paroxysmal nocturnal haemoglobinuria (PNH) patients outside open clinical trials assessing the complement inhibitors and the presence of a PNH clone with evidence of clonal evolution (e.g. myelodysplastic syndrome and leukaemia) [1]. Haploidentical HSCT (haploHSCT) is now increasingly applied as a curative therapy for patients with haematologic diseases. This study aimed to evaluate the outcomes of HSCT treatment for 28 patients with PNH who underwent haplo-HSCT at our centres. All 28 patients with PNH who underwent haplo-HSCT at our centre between October 2010 and December 2018 were enroled in this study. Details of conditioning regimen, graft collection and infusion, graft versus host disease (GVHD) prophylaxis and treatment strategy, supportive care and post-transplantation surveillance, and other supportive care are consistent with our previous experience [2]. The baseline characteristics and demographics are reported descriptively with continuous variables summarized by median and range. Survival curves were calculated using a Kaplan–Meier analysis. All statistical analyses were based on the data available on January 31, 2019, and were performed with SPSS version 16.0 (SPSS, Chicago, IL, USA). The data for all patient and donor characteristics at the time of transplantation are shown in Table 1. At the time of transplantation, the median age was 28 (range 6–54) years, and the median disease duration was 6 (range 3–120) months. The patients received various treatments, such as steroids (n= 2), androgens (n= 5), cyclosporine+ androgens (n= 13), ATG+ cyclosporine+ androgens (n= 1), and growth factors, before transplantation. Five patients had classical PNH, and 23 patients had PNH-AA syndrome. The median age of the donors was 40 (range 11–57) years. The median values for MNCs and CD34 cells were 10.68 × 10/kg (range 4.80–33.40 × 10/kg) and 3.59 × 10/kg (range 0.68–5.91 × 10/kg), respectively. One patient (underwent HSCT in December 2018) was not evaluable for engraftment or haematopoietic recovery because of early death on day +14 due to septicaemia. The 27 evaluable patients all achieved myeloid engraftment and complete chimerism (>95%), and one patient experienced secondary graft failure. Three patients demonstrated delayed platelet recovery, and one patient demonstrated platelet graft failure. The median time to neutrophil recovery was 12 (range 9–26) days, and the median time to platelet recovery was 16 (range 11–75) days. In 27 evaluable patients, the cumulative incidences on day +100 were 29.63% for grades I–IV aGVHD and 14.82% for grades II–IV aGVHD. No patient experienced grades III to IV aGVHD. The cumulative incidence of cGVHD was 28.81%, and the cumulative incidence of moderate-severe cGVHD was 11.73%. These authors contributed equally: Limin Liu, Yanming Zhang, Shan Liu