Adding nipocalimab to standard-of-care (SoC) demonstrates sustained disease control through week 120 in antibody-positive adult patients with generalized myasthenia gravis (gMG), including anti-AChR* or anti-MuSK**, according to the Vivacity-MG3 open-label extension (OLE) study presented at AAN 2026.
“For people living with gMG, consistent and durable symptom control is the central goal of treatment,” said study co-author Associate Professor Constantine Farmakidis, University of Kansas Medical Center, in a press release.
“These long-term results, now extending beyond 2 years, provide further evidence that disease control, as initially observed in the nipocalimab phase III pivotal study, can be sustained, and add to the body of evidence that may guide clinical decision-making,” Farmakidis added.
Nipocalimab, added to SoC, is the first approved neonatal Fc receptor blocker for the treatment of gMG in adult and adolescent (aged ≥12 years) patients who are anti-AChR or anti-MuSK antibody positive, said co-author Dr Carlo Antozzi from Fondazione IRCCS Istituto Neurologico Carlo Besta in Milan, Italy, who presented the study.
In the double-blind phase of the study, individuals with AChR, MuSK, or LRP4*** antibody-positive gMG were randomly assigned in a 1:1 ratio to receive either nipocalimab+ (n=77) or placebo (n=76) in addition to SoC for 24 weeks.
Following completion of the 24-week double-blind phase, 137 antibody-positive participants entered the 120-week OLE phase, where those initially receiving nipocalimab continued their treatment regimen (nipocalimab/nipocalimab + SoC group), and those previously on placebo were switched to nipocalimab (placebo/nipocalimab + SoC group).
By week 96, improvements in MG-Activities of Daily Living (MG-ADL) scores were observed in both treatment groups, with mean reductions of 6.47 points in the nipocalimab/nipocalimab group and 6.69 points in the placebo/nipocalimab group. [AAN 2026, abstract 9-19]
As a result, 50 percent of the participants demonstrated minimal symptom expression (MSE), with nearly one-third achieving sustained MSE for ≥8 weeks.
Quantitative Myasthenia Gravis (QMG) scores were also improved in both the nipocalimab/nipocalimab and placebo/nipocalimab groups, with mean reductions of 6.47 and 6.69 points, respectively.
Levels of immunoglobulin G (IgG) were also reduced from baseline to week 96, with 64.06- and 63.24-percent reductions in the nipocalimab/nipocalimab and placebo/nipocalimab groups, respectively.
At baseline, approximately 45 percent of patients were using corticosteroids. Those in the nipocalimab/nipocalimab group began discontinuing corticosteroids as early as week 24, with a subsequent decline over time, resulting in more than half of patients (57.3 percent) reaching a prednisone equivalent dose of ≤10 mg per day.
In terms of safety, the rates of adverse events were comparable between the double-blind and OLE phases, with no new safety concerns observed, Antozzi noted.
“Overall, long-term treatment with nipocalimab demonstrated clinically meaningful and sustained disease control over 120 weeks in a broad population of autoantibody-positive patients with gMG, while maintaining an acceptable safety profile,” he concluded.