A Study to Test How Safe Pozelimab and Cemdisiran Combination Therapy and Cemdisiran Alone Are and How Well They Work in Adult Patients With Generalized Myasthenia Gravis

Summary

This study is researching the experimental drugs called pozelimab and cemdisiran, and cemdisiran monotherapy. The study is focused on patients with generalized Myasthenia Gravis (gMG). Myasthenia gravis is a disease that causes weakness and fatigue in muscles in the body because the nerves and muscles are not communicating properly. The aim of the study is to see how effective pozelimab and cemdisiran are when used in combination and when pozelimab and cemdisiran are used alone for patients with gMG. The study is looking at several other research questions, including: * What side effects may happen from taking the study drugs * How the study drugs work inside the body * How much of the study drugs are in the blood at different times * Whether the body makes antibodies against pozelimab and cemdisiran (which could make the drugs less effective or could lead to side effects)

Timeline

Start

2021-12-14

Primary completion

2025-07-08

Completion

2028-11-11

Outcome

Met primary endpoint

paper Placebo-adjusted least-squares mean differences in MG-ADL score at week 24 were -2·3 (SE 0·7; 95% CI -3·6 to -1·0; p=0·0005) PMID 42030965 ↗

paper -1·7 (0·7; -3·0 to -0·4; p=0·0086) in the combination group. PMID 42030965 ↗

release “primary and key secondary endpoints were met in the Phase 3 NIMBLE trial assessing investigational cemdisiran monotherapy in adults with generalized myasthenia gravis” regeneron.com ↗

release “NIMBLE trial met its primary and key secondary endpoints at week 24” regeneron.com ↗

Publications

• Vu T, Habib AA, Jacob S, Mantegazza R, Murai H, Vissing J, Shaibani A, Levine T, Hussain Y, Meisel A, Adamczak-Ratajczak A, Ilkowski J, Sgobbi P, Guerreiro A, Luo S, Pavani R, Chaudhari U, Jalali N, DeVeaux M, Moore W, Meagher KA, Burczynski ME, Kokate S, Sherman S, Pawaskar D, Singh N, Souttou A, Sirulnik A, Perlee L, Yancopoulos GD, Howard JF Jr; NIMBLE Trial Investigators. Efficacy and safety of cemdisiran siRNA in myasthenia gravis (NIMBLE): a double-blind, randomised, placebo-controlled, phase 3 trial. Lancet. 2026 May 2;407(10540):1712-1725. doi: 10.1016/S0140-6736(26)00690-2. Epub 2026 Apr 21.

Drugs

Evaluation	Drug	Modality	Dose	Route
Subject	Cemdisiran	Small interfering RNA (siRNA)	200 mg	Subcutaneous
Subject	Cemdisiran	Small interfering RNA (siRNA)	600 mg	Subcutaneous
Subject	Pozelimab	Monoclonal antibody	200 mg	Subcutaneous

Indications