Nipocalimab Becomes First Approved Treatment for Warm AIHA
The FDA approved nipocalimab (Imaavy) for warm autoimmune hemolytic anemia in adults and adolescents who have used corticosteroids. The drug blocks the neonatal Fc receptor to reduce pathogenic IgG autoantibodies while preserving B-cell function. In a phase II/III trial, 24% of treated patients achieved a durable hemoglobin response versus 8% with placebo.
The approval marks a shift from broad immunosuppression toward targeted therapy in wAIHA, a condition where IgG autoantibodies attack red blood cells at normal body temperatures. Prior standard care relied on corticosteroids and immunosuppressants, which manage symptoms but leave the underlying antibody-driven mechanism untouched. Nipocalimab's FcRn blockade selectively lowers pathogenic IgG while sparing B cells, offering a more precise intervention. The ENERGY trial enrolled patients with hemoglobin below 10 g/dL and confirmed hemolysis, allowing concurrent background treatments. Notably, nipocalimab already held approval for generalized myasthenia gravis, extending its clinical footprint into hematologic disease.
This approval could reshape care for wAIHA patients who have exhausted corticosteroid options, potentially reducing reliance on long-term immunosuppression with its attendant side effects. The modest response rate — 24% versus 8% placebo — suggests meaningful benefit for a subset, though many patients may still need additional therapies. Patients and hematologists may gain a new first-line targeted option, while payers and health systems will weigh the drug's cost against its demonstrated efficacy and safety profile.