IMAAVY Shows Durable Haemoglobin Response in Phase 2/3 Study for Warm Autoimmune Haemolytic Anaemia
Thursday, June 11, 2026
Johnson & Johnson has reported positive results from the Phase 2/3 ENERGY study, showing that IMAAVY® (nipocalimab-aahu) achieved a statistically significant and durable haemoglobin response in patients with warm autoimmune haemolytic anaemia (wAIHA), a rare autoimmune disease with no FDA-approved treatments.
The results, presented at the European Hematology Association Congress 2026, showed that patients receiving the 30 mg/kg dose of IMAAVY were around three times more likely to achieve a durable haemoglobin response than those receiving placebo over a 24-week period.
Warm autoimmune haemolytic anaemia is a life-threatening condition in which the immune system mistakenly destroys red blood cells, leading to anaemia and severe fatigue. Current treatment options mainly rely on corticosteroids and broad immunosuppressive therapies.
The randomised, placebo-controlled ENERGY study met its primary endpoint of durable haemoglobin improvement. This was defined as achieving an increase in haemoglobin of at least 2 g/dL from baseline, maintaining haemoglobin levels of at least 10 g/dL, meeting these criteria across multiple visits, and doing so without the need for rescue therapy or changes to background treatment.
Patients treated with IMAAVY showed a rapid treatment effect, with an average haemoglobin increase of 1 g/dL observed as early as the first week of treatment, while no meaningful change was reported in the placebo group. By Week 24, nearly two-thirds of patients receiving the treatment achieved both a haemoglobin level of at least 10 g/dL and an increase of at least 2 g/dL from baseline.
The study also demonstrated improvements in patient-reported fatigue and reductions in steroid use, both of which were secondary endpoints. Improvements in fatigue were observed by Week 2 and were maintained throughout the treatment period.
IMAAVY demonstrated a safety profile consistent with that seen in its approved use for generalized myasthenia gravis. The most commonly reported adverse events in treated patients were peripheral oedema, diarrhoea and fever.
The therapy is designed to selectively target pathogenic IgG autoantibodies responsible for red blood cell destruction while preserving important immune system functions. This approach may offer a targeted treatment option for patients with wAIHA, a disease area where approved therapies remain unavailable.
The findings represent an important development for the treatment of warm autoimmune haemolytic anaemia and support the continued clinical advancement of IMAAVY in autoimmune diseases.
Source: prnewswire.com
