Nipocalimab‐aahu in generalised myasthenia gravis: A new Fc receptor‐targeted option for antibody‐positive patients

Myasthenia gravis (MG) is an autoimmune disorder driven by pathogenic IgG autoantibodies, leading to muscle weakness and impaired quality of life. Conventional immunosuppressant therapies are often limited by side effects and incomplete efficacy. Nipocalimab-aahu (N-a), recently FDA-approved, is a novel neonatal Fc receptor (FcRn) antagonist that reduces circulating IgG levels, targeting the underlying disease mechanism. This review synthesizes evidence on N-a's efficacy, safety, and clinical positioning. Phase 2 and 3 trials (Vivacity-MG/MG3) demonstrated that N-a significantly improves the Myasthenia Gravis Activities of Daily Living (MG-ADL) score compared to placebo, with a favorable safety profile. The most common adverse events were nasopharyngitis and headache, with no increased serious infection risk or clinically significant hypoalbuminemia. Compared to other biologics, N-a offers a distinct mechanism, selective IgG reduction without broad immunosuppression and a convenient bi-weekly dosing regimen. While it shows promise for reduced systemic immunosuppression and potentially greater efficacy in MG-ADL improvement than some alternatives, cross-trial comparisons are limited. Key limitations include the need for long-term safety data and more research in underrepresented populations, including pediatric and seronegative patients. In conclusion, N-a represents a significant advancement in generalized MG (gMG) treatment, providing a targeted, effective, and well-tolerated option that addresses a key unmet need for patients with acetylcholine receptor (AChR) or muscle-specific kinase (MuSK) antibody-positive disease.