Daratumumab for Delayed Red Cell Engraftment after Hematopoietic Stem Cell Transplant

We describe a case of treatment-refractory pure red cell aplasia following a major ABO-mismatchedallogeneic stem cell transplant successfully treated with daratumumab.The 72-year-old patient with MDS received a matched unrelated donor transplant with a major ABO incompatibility, recipient blood group O from blood group A donor. Despite prompt engraftment with WBC and platelet recovery he remained anemic and RBC transfusion dependent. Bone marrow biopsy showed <1% erythroid elements concerning for post-transplant PRCA. 200 days post-transplant he had persistent circulating anti-A antibodies and no signs of red cell recovery. Standard treatments including tapering of immunosuppression, steroids, rituximab and erythropoiesis stimulating agents had no effect. The patient remained transfusion dependent with 1-2 units per week. Following treatment with daratumumab 390 days post transplant, he achieved transfusion-independence promptly within one week of treatment with daratumumab and continues to have normal erythropoiesis 10 months after daratumumab treatment. Anti-A antibodies became undetectable. The patient tolerated daratumumab well and no signs of GVHD or opportunistic infections were observed.We describe the use of daratumumab in patients with PRCA after major ABO mismatch allogeneic stem cell transplant. We hypothesized that a selective treatment targeting the CD38 positive plasma cells would decrease anti-A antibody production and allow for RBC recovery. Our findings su...
Source: Blood - Category: Hematology Authors: Tags: 401. Basic Science and Clinical Practice in Blood Transfusion: Poster II Source Type: research