New Phase 3 trial data support efficacy of nipocalimab in gMG
Treatment leads to significant reductions in disease severity in pivotal study
Treatment with nipocalimab led to significant reductions in disease severity among people with generalized myasthenia gravis (gMG), as assessed by a drop in the MG Activities of Daily Living (MG-ADL) score, according to top-line data from a pivotal Phase 3 trial.
Findings from the trial, dubbed VIVACITY-MG3 (NCT04951622) — which is evaluating the nipocalimab’s efficacy and safety in adults with gMG — were presented by therapy developer Johnson & Johnson at this year’s European Academy of Neurology (EAN) Congress, which wrapped up earlier this month in Finland.
The trial is still recruiting patients at sites across North America, Europe, East Asia, and Australia, and is expected to conclude in 2026. Based on its findings, the company expects to submit applications to regulatory authorities later this year requesting nipocalimab’s approval for gMG.
“We are thrilled to present yet another dataset for nipocalimab at the EAN 2024 Annual Meeting highlighting our commitment to providing innovative treatments for autoantibody-driven diseases,” Katie Abouzahr, MD, vice president and leader of the autoantibody and maternal-fetal immunology disease area at Johnson & Johnson Innovative Medicine, said in a company press release.
Carlo Antozzi, MD, Johnson & Johnson’s medical consultant and a neurologist at the Neurological Institute Foundation Carlo Besta, in Italy, added that the company is “encouraged by the potential of nipocalimab to uniquely help address this gap for people living with myasthenia gravis.”
Treatment designed to block activity of FcRn protein
MG occurs when self-reactive antibodies mistakenly attack proteins at the neuromuscular junction — the site where nerve and muscle cells come into contact and communicate. gMG is a more severe type of the disease, characterized by widespread muscle weakness and fatigue.
Nipocalimab is designed to block the activity of the neonatal Fc receptor (FcRn), a protein that normally helps to prevent immunoglobulin G (IgG) antibodies, including the self-reactive ones that drive MG, from being degraded. The therapy is thereby expected to help ease MG severity by promoting the degradation and lowering the levels of IgG antibodies.
The safety and efficacy of nipocalimab were earlier assessed in the Phase 2 VIVACITY-MG study (NCT03772587), which enrolled 68 adults with moderate to severe gMG.
In that study, nipocalimab was well tolerated and led to a significant reduction in IgG levels. The treatment also eased MG severity, as assessed by a significantly higher proportion of nipocalimab-treated patients showing a reduction in MG-ADL scores — which was sustained for at least four weeks, or about one month — compared with those given a placebo (51.9% vs. 15.4%).
Drop in daily living activities score seen with nipocalimab use
The Phase 3 study is further evaluating nipocalimab’s safety and efficacy in about 199 adults with gMG. Most participants (153) had self-reactive antibodies targeting acetylcholine receptors (AchRs), muscle-specific kinase (MuSK), and/or low-density lipoprotein receptor-related protein 4 (LRP4).
Patients were randomly assigned to receive either nipocalimab or a placebo, plus standard of care, for up to 24 weeks or about six months. Nipocalimab was given by into-the-vein (intravenous) infusions every two weeks after an initial loading dose, also administered intravenously.
The trial met its primary goal, with nipocalimab-treated patients seeing their MG-ADL scores decrease by a mean of 4.7 points from the study’s start (baseline) to weeks 22 to 24 — a significant drop compared with the mean 3.25-point reduction seen in those receiving the placebo.
Critical secondary outcomes also were met, including a significant improvement in muscle strength and function after 22 to 24 weeks. This was measured by the Quantitative MG (QMG) scale, a clinician-rated measure of MG disease severity in which higher scores indicate more severe disease. Specifically, patients receiving nipocalimab had a mean reduction of 4.86 points in QMG, while those on a placebo had a mean reduction of 2.05 points.
The sustained response of nipocalimab over six months among this broad myasthenia gravis population is an important finding given the chronic, unpredictable exacerbations typically seen with myasthenia gravis.
Safety and tolerability findings were consistent with other trials, with the overall incidence of adverse events, serious adverse events, and adverse events leading to treatment discontinuation being similar in the two treatment groups.
Antozzi said the company was pleased with these results.
“The sustained response of nipocalimab over six months among this broad myasthenia gravis population is an important finding given the chronic, unpredictable exacerbations typically seen with myasthenia gravis,” Antozzi said.
Johnson & Johnson stated in the release that the therapy was the “first-and-only FcRn blocker to demonstrate superiority in activities of daily living … over placebo when added to standard of care over 24 weeks in antibody positive patients.”
About the Author
