Johnson & Johnson (NYSE: JNJ) reported results from its Phase 2/3 ENERGY study showing IMAAVY (nipocalimab-aahu) produced statistically significant hemoglobin improvements in patients with warm autoimmune hemolytic anemia compared to placebo.

The randomized, placebo-controlled trial demonstrated that patients receiving the 30 mg/kg dose achieved durable hemoglobin levels at approximately three times the rate of those receiving placebo by 24 weeks. Patients treated with IMAAVY showed a mean hemoglobin improvement of at least 1g/dL as early as Week 1.

The study's primary endpoint measured durable hemoglobin improvement, defined as an increase from baseline of at least 2 g/dL, hemoglobin concentration of at least 10 g/dL for three visits over 28 days starting by Week 16, without rescue therapy or changes to background medications.

Nearly two-thirds of patients in the 30 mg/kg treatment group achieved both a hemoglobin level of at least 10 g/dL and an increase of at least 2 g/dL from baseline by Week 24. The treatment also showed improvements in fatigue and reduction in steroid use.

IMAAVY demonstrated a safety profile consistent with its approved use for generalized myasthenia gravis. The most common adverse reactions in patients with warm autoimmune hemolytic anemia were peripheral edema, diarrhea and fever, each occurring in at least 10% of patients.

Warm autoimmune hemolytic anemia is a rare, life-threatening condition with no FDA-approved treatment options currently available. The company has submitted a supplemental Biologics License Application for IMAAVY, which has received FDA Priority Review.

The results were presented at the European Hematology Association 2026 Congress, according to the company's statement.