Cemdisiran shows potential in Phase 3 myasthenia gravis trial

Phase 3 NIMBLE trial data for cemdisiran, an investigational small interfering RNA (siRNA) therapy, shows potential efficacy in treating generalized myasthenia gravis (gMG). Developed by Regeneron, cemdisiran targets the liver to reduce the hepatic production of complement component 5 (C5) before it enters circulation, offering a different mechanism than existing peripheral C5 inhibitors.

In the 24-week double-blind period of the NIMBLE trial, cemdisiran met its primary endpoint, showing a placebo-adjusted improvement in the Myasthenia Gravis–Activities of Daily Living score. Exploratory analysis regarding hospitalization also showed clinical significance: 3.8% of patients on cemdisiran experienced MG-related hospitalization compared to 15.3% in the placebo group. Notably, no patients treated with cemdisiran experienced a myasthenic crisis requiring hospitalization during the study period.

Ali Habib, MD, a professor of neurology at the University of California, Irvine, noted that preventing hospitalizations and myasthenic crises is critical for the patient population, which often includes older individuals with comorbid conditions.