At a Glance
- Johnson & Johnson has submitted a Biologics License Application (BLA) to the U.S. FDA for IMAAVY® (nipocalimab-aahu) in warm autoimmune hemolytic anemia (WAIHA).
- Nipocalimab is a first-in-class FcRn-blocking monoclonal antibody designed to reduce pathogenic IgG autoantibodies.
- If approved, it would become the first FDA-approved therapy specifically indicated for WAIHA.
- Phase 3 data demonstrated clinically meaningful and sustained hemoglobin improvement with a favorable safety profile
Written by: Marka Sheshi, PharmD
Reviewed By: Pharmacally Editorial Team
Johnson & Johnson recently submitted a supplemental Biologics License Application (sBLA) to the FDA for IMAAVY® (nipocalimab-aahu) to treat warm autoimmune hemolytic anemia (wAIHA), a rare disease with no approved therapies.
This milestone builds on positive Phase 2/3 ENERGY trial data, highlighting potential rapid hemoglobin improvements and fatigue reduction in affected adults.
ENERGY Trial Results
The Phase 2/3 ENERGY study (NCT04119050) was a randomized, double-blind, placebo-controlled trial in wAIHA adults. More nipocalimab-treated patients hit the primary endpoint: durable hemoglobin response (≥10 g/dL, ≥2 g/dL increase from baseline for ≥28 days without rescue therapy). Patients also showed rapid, sustained fatigue improvements via FACIT-Fatigue scores, with good tolerability matching the gMG label no new safety signals. Full results are pending for publication.
Safety Profile
IMAAVY® was well-tolerated in ENERGY, consistent with prior data. Common adverse reactions (≥10%) in gMG trials included respiratory tract infections, peripheral edema, and muscle spasms. For full details on warnings (e.g., infections, hypersensitivity, infusion reactions), precautions, and adverse reactions, see the official FDA prescribing information: IMAAVY™ Prescribing Information (PDF). Note: IMAAVY® is not approved for wAIHA yet.
Understanding wAIHA
Warm autoimmune hemolytic anemia affects about 1 in 8,000 people in the US, where IgG autoantibodies destroy red blood cells, causing anemia. Patients face severe risks, including 20-30% higher mortality, chronic fatigue, transfusion needs, and complications like thrombosis or organ failure. Current care relies on unapproved corticosteroids or immunosuppressants, leaving substantial unmet needs.
IMAAVY® Mechanism
IMAAVY® selectively blocks the neonatal Fc receptor (FcRn), reducing harmful IgG autoantibodies while sparing key immune functions like responses to new infections. Approved since April 2025 for generalized myasthenia gravis (gMG) in AChR- or MuSK-positive patients aged 12+, it targets autoantibody-driven diseases. IMAAVY® is also being studied for systemic lupus erythematosus (SLE) in the JASMINE trial and Sjögren’s disease in the landmark DAHLIAS Phase 2 trial
Regulatory Designations
Nipocalimab has received multiple FDA and EMA designations supporting its development, including Fast Track for wAIHA (July 2019), Orphan Drug status (December 2019), and Breakthrough Therapy for related indications like HDFN and Sjögren’s disease. These recognitions underscore its potential in rare autoantibody conditions, with Priority Review granted for gMG in 2024.
Reference
Johnson & Johnson seeks FDA approval of IMAAVY® (nipocalimab-aahu) as the first-ever FDA-approved treatment for warm autoimmune hemolytic anemia (wAIHA), 24 February 2026, Johnson & Johnson seeks FDA approval of IMAAVY® (nipocalimab-aahu) as the first-ever FDA-approved treatment for warm autoimmune hemolytic anemia (wAIHA)
Efficacy and Safety of M281 in Adults with Warm Autoimmune Hemolytic Anemia (ENERGY), ClinicalTrials.gov ID NCT04119050, https://clinicaltrials.gov/study/NCT04119050
About Writer
Marka Sheshi | Doctor of Pharmacy
Driven by a deep commitment to clinical excellence, research integrity, and impactful medical writing. With a strong foundation in pharmacotherapy and patient safety, specializes in transforming complex scientific evidence into authoritative, publication-ready content. Passionate about advancing healthcare through precise, evidence-based communication that informs practice, strengthens research visibility, and improves patient outcomes.