Regeneron's siRNA therapeutic cemdisiran met primary and secondary endpoints in the Phase III NIMBLE trial for generalised myasthenia gravis (gMG), showing 4.52-point improvement on the MG-ADL scale versus 2.22 for placebo at 24 weeks. The complement C5 inhibitor demonstrated efficacy with quarterly 600mg subcutaneous dosing, potentially offering superior convenience versus approved C5 inhibitors requiring biweekly or daily administration. Regeneron plans a regulatory submission in its US homeland in Q1 2026.

Safety data showed 69% treatment-emergent adverse events (TEAE) for monotherapy versus 77% for placebo, with no treatment discontinuations in the monotherapy arm. The trial evaluated both monotherapy and combination with pozelimab, though monotherapy showed numerically better outcomes. Cemdisiran, developed with Alnylam Pharmaceuticals, represents the first siRNA candidate for this autoimmune disorder affecting 85,000 US patients where complement activation drives neuromuscular junction impairment.

According to PharmCube's NextBiopharm® database, cemdisiran is under development in eight other indications. Click here to request a free trial for NextBiopharm®.