Successful Use of Sutimlimab in two Pediatric Patients With Refractory Cold Antibody‐Mediated Autoimmune Hemolytic Anemia

Cold antibody-mediated autoimmune hemolytic anemia, or cold agglutinin syndrome (CAS), in pediatrics is typically transient, although it can often be severe and require transfusion support. Recurrence in children is rare, but those with underlying immune dysfunction can have a refractory course with limited options available. We report a 4-year-old girl with Evans syndrome and life-threatening CAS refractory to transfusions, plasmapheresis, steroids, and immunosuppression as well as a 12-month-old boy status post liver transplant with CAS refractory to steroids, rituximab, and tacrolimus cessation with transition to sirolimus, both of whom received sutimlimab, a C1s inhibitor, with rapid improvement in hemolysis, transfusion independence, and a sustained remission. To our knowledge, these are the first reported uses of sutimlimab in the pediatric population.