Johnson & Johnson has announced the submission of a supplemental Biologics License Application (sBLA) to the U.S. Food and Drug Administration (FDA) seeking approval of IMAAVY as a potential first-ever treatment for patients with warm Autoimmune Hemolytic Anemia (wAIHA).

Warm autoimmune hemolytic anemia is a rare and serious autoantibody-driven condition affecting approximately one in 8,000 people in the United States. The disease is associated with significant morbidity and mortality, with patients facing a 20–30 percent higher risk of death. Currently, there are no FDA-approved therapies specifically indicated for wAIHA.

The condition occurs when immunoglobulin G (IgG) autoantibodies bind to and destroy red blood cells, leading to anemia. IMAAVY is designed to selectively block the neonatal Fc receptor (FcRn), which regulates IgG recycling. By lowering circulating IgG levels, including pathogenic autoantibodies, the therapy aims to address the underlying cause of disease while preserving essential immune functions.

The sBLA submission is supported by results from the Phase II/III ENERGY study , a multicentre , randomised, double-blind, placebo-controlled trial evaluating nipocalimab in adults with wAIHA. Data from the study showed that a higher proportion of patients treated with IMAAVY achieved the primary endpoint of a durable hemoglobin response compared with placebo. Durable response was defined as maintaining hemoglobin levels above 10 g/dL with an increase of at least 2 g/dL for a minimum of 28 days without requiring rescue therapy.

In addition to hemoglobin improvement, patients receiving IMAAVY demonstrated rapid and sustained reductions in fatigue, as measured by the FACIT-Fatigue scale — a key patient-reported outcome in wAIHA.

David M. Lee, Global Immunology Therapeutic Area Head at Johnson & Johnson, said the filing marks a significant milestone for patients living with a life-threatening disease that lacks approved treatment options. He added that the company remains committed to developing targeted, immunoselective therapies that deliver meaningful clinical benefits.

Bruno Fattizzo, Assistant Professor at the Department of Oncology and Hematology-Oncology at the Università degli Studi di Milano, noted that the ENERGY study results demonstrated clinically meaningful improvements in both hemoglobin levels and fatigue while maintaining favorable tolerability.