Positive phase III results for nipocalimab in generalised myasthenia gravis

The Vivacity-MG3 phase IIIAu cours d’un essai clinique de phase III, un médicament, pour lequel on a déterminé lors d’essais antérieurs l’innocuité et le dosage optimum (essais de phase I et II), est administré à un grand groupe de malades, sur une longue durée, dans le but d’évaluer son efficacité thérapeutique en la comparant à celle d’un traitement de référence ou un placebo. Il permet aussi de mettre en évidence les interactions indésirables et les effets secondaires du traitement à moyen terme. Au terme de cet essai, le médicament peut obtenir une autorisation de mise sur le marché. trial included 153 adults with generalised myasthenia to evaluate nipocalimab, a monoclonal antibody targeting the neonatal Fc receptor (FcRn).

• Of all the patients, 88% had anti-RACh autoantibodies, 11% had anti-MuSK autoantibodies and 2% had anti-LRP4 autoantibodies.
• Patients were randomised into two groups: 77 received nipocalimab and 76 a placeboLe placebo est un produit dont la présentation est identique à celle d’un médicament, mais qui ne contient pas de principe actif. Dans un essai clinique, un placebo est utilisé pour mesurer l’action réelle du médicament testé, en comparant les effets du médicament testé contenant le principe actif et ceux du placebo., every fortnight for six months. All patients received additional care as usual.
• A significantly greater reduction in the MG-ADL score compared with baseline (primary endpoint) was observed at six months in the nipocalimab group than in the placebo group.
• A significantly greater reduction in the Quantitative Myasthenia Gravis (QMG) score at six months compared to baseline was also observed with nipocalimab.
• A rapid and sustained reduction in IgG, correlated with a greater improvement in symptoms, was observed with nipocalimab.
• Nipocalimab was well tolerated, with mostly mild to moderate adverse events.

The open-label extension phase of the Vivacity-MG3 trial will provide longer-term efficacy and safety data.

Safety and efficacy of nipocalimab in adults with generalised myasthenia gravis (Vivacity-MG3): a phase 3, randomised, double-blind, placebo-controlled study. Antozzi C, Vu T, Ramchandren S et al. Lancet Neurol. 2025 Feb.