Daratumumab in the Management of Red Cell Aplasia Following Allogeneic Hematopoietic Stem Cell Transplantation.

Pure red cell aplasia (PRCA) is a rare but significant complication following major ABO-incompatible allogeneic hematopoietic stem cell transplantation (HSCT). The persistence of recipient B lymphocytes producing anti-donor isohemagglutinins leads to reticulocytopenia and anemia, often resulting in transfusion dependence. Current treatment options for post-HSCT PRCA are limited and frequently yield suboptimal responses, complicating patient management. Herein, we report three cases of post-HSCT PRCA successfully managed with daratumumab, a monoclonal antibody targeting CD38-expressing plasma cells. All patients demonstrated rapid reticulocyte recovery and transfusion independence after daratumumab treatment, despite prior treatment failures. These findings suggest that daratumumab may provide a more effective therapeutic approach, with a favorable safety profile compared to traditional therapies. Given its demonstrated efficacy and safety, daratumumab warrants consideration as a first-line treatment for post-HSCT PRCA, potentially improving patient quality of life and reducing transfusion-related complications. Further studies should explore optimal dosing and long-term outcomes.