Protective Effect of Rituximab in Chronic Graft-Versus-Host Disease Occurrence in Allogeneic Transplant patients with Epstein Barr Virus Viremia.

B cells are involved in chronic graft-versus-host disease (cGVHD) pathogenesis, and Rituximab may have a therapeutic effect on cGVHD in allogeneic hematopoietic stem cell transplantation (allo-HSCT) patients. Herein, we retrospectively evaluated the prophylactic effect of Rituximab on cGVHD in a group of Chinese allo-HSCT patients. A total of 102 patients, who suffered Epstein Barr virus (EBV) viremia within 100 days after allo-HSCT, were included in this study. Fifty patients received Rituximab (375 mg/m2 weekly) for EBV viremia, while fifty-two patients did not receive Rituximab. A competing risk model was adopted to compare cumulative incidence of cGVHD, cumulative incidence of relapse (CIR) and transplantation-related mortality (TRM) between two groups. Cumulative incidence of cGVHD in the Rituximab group was lower than in controls ( P  = 0.0579). Multivariate analyses confirmed that Rituximab was an independent factor for the reduction of cumulative cGVHD incidence ( P  = 0.0069). No significant difference was observed in CIR ( P  = 0.39) or TRM ( P  = 0.48) between two groups and 2-year OS and DFS were comparable (OS, P  = 0.667; DFS, P  = 0.571). Administration of Rituximab in the early post-transplantation phase may protect against cGVHD in allo-HSCT patients without increasing CIR or TRM.