Johnson & Johnson (NYSE: JNJ) announced data from its Phase 3 Vivacity-MG3 study showing that IMAAVY (nipocalimab-aahu) maintained disease control in adults with generalized myasthenia gravis through 120 weeks of follow-up.

The study tracked 153 antibody-positive patients, including those with anti-AChR and anti-MuSK antibodies. At 96 weeks in the open label extension phase, patients receiving IMAAVY showed mean reductions of 6.47 points on the MG-ADL scale and 5.97 points on the QMG scale, which measure symptom impact on daily living and muscle strength.

Half of the patients achieved minimal symptom expression, with nearly one-third maintaining this status for at least 8 weeks. Additionally, 57% of patients reached low corticosteroid doses of 10 mg/day or less, and total immunoglobulin G levels were reduced by more than 64%.

A post-hoc analysis from the 24-week double-blind portion found that patients receiving IMAAVY plus standard of care were four times more likely to achieve sustained minimal symptom expression compared to those on placebo. Patients who maintained this symptom control level showed greater improvements in quality of life.

"These long-term results, now extending to beyond two years, provide further evidence that disease control can be sustained," said Constantine Farmakidis, Associate Professor of Neurology at the University of Kansas Medical Center.

Johnson & Johnson also announced that its EPIC study, comparing IMAAVY with efgartigimod in adults with generalized myasthenia gravis who have never received an FcRn blocker, is now enrolling participants.

The company presented these findings among seven abstracts at the American Academy of Neurology 2026 Meeting in Chicago. IMAAVY is currently approved for treating generalized myasthenia gravis in adults and pediatric patients 12 years and older who are AChR or MuSK antibody positive.