On April 30, 2025, the U.S. Food and Drug Administration (FDA) approved Imaavy (nipocalimab-aahu) for the treatment of adults and adolescents (aged ≥12 years) with generalized myasthenia gravis (gMG) who are positive for acetylcholine receptor (AChR) or muscle-specific kinase (MuSK) antibodies. Developed by Johnson & Johnson, Imaavy is the first neonatal Fc receptor (FcRn) blocker to receive approval for this population, covering a broader spectrum of gMG patients than previous FcRn-targeting agents. The approval was based on data from the Phase III Vivacity-MG3 trial and its open-label extension, which demonstrated rapid and sustained reductions in pathogenic IgG levels, along with clinically meaningful improvements in muscle strength and daily function. The median duration of disease control extended beyond 20 months for many patients. Imaavy will be available at a list price of $12,480 per 1200 mg vial, with quarterly maintenance dosing projected after initial loading. Analysts anticipate peak global annual revenues exceeding $5 billion. This approval not only broadens the FcRn class in gMG but introduces the first option approved for both AChR- and MuSK-positive disease, including pediatric use, which may disrupt treatment algorithms currently dominated by Vyvgart and Zilbrysq.

Citation: https://www.investor.jnj.com/news/news-details/2025/Johnson--Johnson-receives-FDA-approval-for-IMAAVY-nipocalimab-aahu-a-new-FcRn-blocker-offering-long-lasting-disease-control-in-the-broadest-population-of-people-living-with-generalized-myasthenia-gravis-gMG/default.aspx

Implication: Imaavy’s approval reshapes the gMG landscape with broader antibody and pediatric inclusion, challenging existing FcRn incumbents.