The pharmaceutical giant Johnson & Johnson has announced it has submitted a supplemental Biologics License Application (sBLA) to the US Food and Drug Administration (FDA), seeking approval of IMAAVY (nipocalimab-aahu) as the first-ever treatment for patients with warm autoimmune haemolytic anaemia (wAIHA).
Why this matters
wAIHA is a rare and life-threatening disease in which pathogenic immunoglobulin (IgG) autoantibodies attach to and destroy red blood cells, leading to debilitating anaemia.
The condition is linked to significant morbidity and mortality, with individuals affected by the disease experiencing a 20-30% higher risk of death.
Currently, there are no approved treatments available, despite the large unmet need, as the disease affects approximately 1 in 8000 people in the US.
"People living with warm autoimmune haemolytic anaemia face a serious, life-threatening disease with no approved treatment options and a high risk of complications, including profound chronic fatigue, transfusion dependence and organ failure," said Dr David M Lee, Global Immunology Therapeutic Area Head, Johnson & Johnson.
The submission of this sBLA represents an important milestone for the wAIHA community and underscores our commitment to advancing targeted, immunoselective therapies that can deliver meaningful, rapid improvement for these patients.
wAIHA occurs when harmful immunoglobulin G (IgG) autoantibodies attach to and destroy red blood cells, leading to anaemia.
IMAAVY is designed to selectively block the neonatal Fc receptor (FcRn), a key regulator of IgG recycling.
By reducing circulating IgG, including autoantibodies, IMAAVY targets the underlying cause of disease while preserving critical immune functions, including some humoral B-cell responses to new infections.
The sBLA submission is supported by the Phase II/III ENERGY multicenter, randomised, double-blind, placebo-controlled study evaluating IMAAVY in adults with warm autoimmune haemolytic anaemia (wAIHA).
The data showed that more patients treated with nipocalimab achieved the stringent primary endpoint of a durable haemoglobin response compared with placebo.
A durable response was defined as achieving a haemoglobin level above 10 g/dL and an increase of at least 2 g/dL for at least 28 days, without the need for rescue therapy.
In addition to a rapid and durable improvement in haemoglobin, more patients treated with IMAAVY experienced rapid and sustained improvement in fatigue as assessed by FACIT-Fatigue, an outcome of significant importance to people living with wAIHA.
"The ENERGY study demonstrated clinically meaningful results in adults living with warm autoimmune haemolytic anaemia," said Dr Bruno Fattizzo, Assistant Professor at the Department of Oncology and Haematology-Oncology, Università degli Studi di Milano.
These results provide a strong rationale for the potential of IMAAVY to rapidly improve fatigue and provide durable haemoglobin response while maintaining favourable tolerability.
IMAAVY was found to be generally well tolerated in ENERGY, with no new safety signals identified and a safety profile consistent with the IMAAVY label.
IMAAVY was approved in the United States in April 2025 for the treatment of generalised myasthenia gravis (gMG) in adult and paediatric patients 12 years of age and older who are acetylcholine receptor (AChR) or muscle-specific kinase (MuSK) antibody positive.