FDA approves Imaavy for rare blood disorder wAIHA

The U.S. Food and Drug Administration (FDA) has approved Imaavy (nipocalimab-aahu), the first treatment specifically for warm autoimmune hemolytic anemia (wAIHA). The approval applies to adults and pediatric patients aged 12 and older who are currently or were previously treated with corticosteroids.

Developed by Johnson & Johnson, Imaavy is an immunoselective neonatal Fc receptor (FcRn) blocker. It is designed to reduce pathogenic immunoglobulin G (IgG) autoantibodies while preserving B-cell function. This mechanism targets the disease-driving antibodies that attack red blood cells, a process that leads to severe anemia, fatigue, and increased risk of morbidity.

The approval is based on results from the Phase 2/3 ENERGY clinical trial. The study demonstrated that patients receiving the approved dose of nipocalimab achieved a durable hemoglobin response at a rate approximately three times higher than those receiving a placebo. Additionally, patients showed improvements in fatigue scores.

Previously, wAIHA treatment relied on broad immunosuppressants or corticosteroids, which suppress the entire immune system rather than targeting specific autoantibodies. wAIHA affects approximately 1 in 8,000 people.