FDA Approves Nipocalimab Generalized Myasthenia Gravis for Adults, Children

The US Food and Drug Administration (FDA) approved nipocalimab-aahu (IMAAVY™) to treat generalized myasthenia gravis (gMG) in adults and children (> 12 years) who are anti-acetylcholine receptor (AChR) or anti-muscular-specific kinase (MuSK) antibody positive.1,2

Announced by Johnson & Johnson on April 30, 2025, the approval of this human FcRn blocking monoclonal antibody marks the second agent on the market for both common subtypes of gMG, following the 2023 approval of rozanolixizumab (Rystiggo; UCB) in adults. However, nipocalimab treats both adults and children.

“We consistently hear from individuals living with myasthenia gravis who are hopeful for new treatment options that may help bring greater stability, independence, and predictability to their lives," said Samantha Masterson, president and CEO of Myasthenia Gravis Foundation of America, in a statement.1 "Today's announcement provides another option which could help address the constant uncertainty and heavy physical and mental toll that MG symptom relapse presents to patients and their families."

Nipocalimab is supplied as a 300 mg/ 1.62 mL and a 1200 mg/6.5 mL (185 mg/mL) single-dose vial per carton for intravenous injection. This immunoselective therapy reduces immunoglobulin, including harmful IgE autoantibodies, without impacting other adaptive and innate immune functions.

Alongside the approval, Johnson & Johnson announced a US-based patient support program called IMAAVY withMe, which helps commercially insured patients prescribed with nipocalimab to receive their first treatment in as quickly as 1 week with payment as little as $0 per infusion. Nipocalimab still remains under review by several other regulatory authorities worldwide.

The FDA decision was backed by results of the ongoing 24-week double-blind, placebo-controlled phase 3 trial called VIVACITY-MG3.3 The trial included 199 adult patients with antibody-positive or negative gMG who had an insufficient response to ongoing standard-of-care therapy. Participants were randomized 1:1 to either nipocalimab plus current standard-of-care (30 mg/kg IV loading dose followed by 15 mg/kg every 2 weeks) or placebo plus standard-of-care.

The trial showed patients on nipocalimab had a 4.70-point improvement in the Myasthenia Gravis-Activities of Daily Living (MG-ADL) score. This was significantly more than the 3.35-point improvement in the placebo arm over weeks 22, 23, and 24 (P = .002). Participants on nipocalimab demonstrated a significant improvement in the Quantitative Myasthenia Gravis score over placebo through weeks 22 and 24 (P < .001).

The phase 2/3 study, VIBRANCE-MG (NCT05265273), supported nipocalimab as a treatment for adolescents with gMG. Investigators evaluated nipocalimab 30 mg/kg IV loading dose, followed by 15 mg/kg IV every 2 weeks, in 7 adolescents aged 12 – 18 years.3,4 Patients demonstrated a statistically significant reduction in total serum immunoglobulin over 24 weeks, with a mean change of –68.98% (SD, 7.561).

"The clinical results we've seen with IMAAVY represent a significant milestone in the treatment of gMG," said Nicholas J. Silvestri, MD, professor of neurology at the University of Buffalo, in a statement. 1 "Patients experienced substantial symptom relief and lasting disease control that translated into better daily function and did not fade over 24 weeks in the pivotal Vivacity-MG3 study. Having a treatment that delivers this level of durable symptom stability is a meaningful step forward for managing a complex and unpredictable disease like gMG, and to have it in both AChR+ and MuSK+ adults and pediatric patients 12 years and older brings an additional FcRn treatment to a broader range of patients."

References

1. 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). PR Newswire. April 30, 2025. https://www.prnewswire.com/news-releases/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-302442650.html. Accessed April 30, 2025.

2. Meglio, M. FDA Approves FcRn Blocker Nipocalimab for Broad Forms of Generalized Myasthenia Gravis. NeurologyLive. April 30, 2025. https://www.neurologylive.com/view/fda-approves-fcrn-blocker-nipocalimab-broad-forms-generalized-myasthenia-gravis. Accessed April 30, 2025.

3. Nipocalimab pivotal Phase 3 trial demonstrates longest sustained disease control in FcRn class. Johnson & Johnson. June 28, 2024. https://www.jnj.com/media-center/press-releases/nipocalimab-pivotal-phase-3-trial-demonstrates-longest-sustained-disease-control-in-fcrn-class. Accessed April 30, 2025.

4. Nipocalimab demonstrates sustained disease control in adolescents living with generalized myasthenia gravis in Phase 2/3 study. Johnson & Johnson. October 15, 2024. https://www.jnj.com/media-center/press-releases/nipocalimab-demonstrates-sustained-disease-control-in-adolescents-living-with-generalized-myasthenia-gravis-in-phase-2-3-study. Accessed April 30, 2025.