Core Insights - Regeneron Pharmaceuticals announced that cemdisiran monotherapy met primary and key secondary endpoints in the Phase 3 NIMBLE trial for generalized myasthenia gravis (gMG), showing a 2.3-point placebo-adjusted improvement in the Myasthenia Gravis Activities of Daily Living (MG-ADL) total score [1][4][9] - The U.S. regulatory submission for cemdisiran monotherapy is planned for the first quarter of 2026, pending discussions with the FDA [1][9] Group 1: Trial Results - Cemdisiran demonstrated an average of 74% inhibition of complement activity, while the combination therapy with pozelimab achieved nearly 99% inhibition [1][2] - In the NIMBLE trial, patients receiving cemdisiran (600 mg every 12 weeks) showed a placebo-adjusted treatment difference of -2.30 in MG-ADL total score and -2.77 in the Quantitative Myasthenia Gravis (QMG) total score [5][6] - The trial included patients with symptomatic gMG who have antibodies to the acetylcholine receptor and assessed changes in daily functioning through patient-reported and physician-administered questionnaires [2][12] Group 2: Efficacy and Safety - Both cemdisiran and cemdi-poze showed improvements in daily functioning at week 24, with cemdisiran showing numerically better results across all gMG-specific outcomes [4][8] - Treatment-emergent adverse events (TEAEs) occurred in 69% of patients treated with cemdisiran, compared to 81% with cemdi-poze and 77% with placebo, with serious TEAEs occurring in 3% of the cemdisiran group [8][7] - No meningococcal infections were reported in the cemdisiran arm, and there were no treatment discontinuations due to adverse events through week 24 [7][8] Group 3: Future Directions - The results of the NIMBLE trial suggest the potential for cemdisiran to provide a best-in-class profile for treating myasthenia gravis with a convenient quarterly subcutaneous administration [2][4] - Regeneron is also investigating the use of cemdisiran and cemdi-poze in other complement-mediated diseases, including paroxysmal nocturnal hemoglobinuria (PNH) and geographic atrophy secondary to age-related macular degeneration [2][13]