The 26-week, double-blind, randomized, placebo-controlled period (RCP) of the CHAMPION MG study (NCT03920293) demonstrated the efficacy and tolerability of the terminal complement C5 inhibitor ravulizumab in patients with anti-acetylcholine receptor antibody-positive (AChR Ab+) generalized myasthenia gravis (gMG). Patients who completed the RCP could receive ravulizumab in the ongoing open-label extension (OLE). _x000D_
To assess ravulizumab’s long-term efficacy and safety in adults with AChR Ab+ gMG._x000D_
In the OLE, patients receive intravenous ravulizumab (blind loading or bridging dose for those previously receiving placebo or ravulizumab, respectively, then 3000–3600 mg according to body weight every 8 weeks) for up to 4 years. Assessments include Myasthenia Gravis-Activities of Daily Living (MG-ADL) and Quantitative Myasthenia Gravis (QMG) total scores and safety evaluations. Interim analysis was conducted of data collected up to Week 60 from RCP baseline._x000D_
Long-term efficacy and safety of ravulizumab were analyzed in 161 and 169 patients, respectively. Patients (n=83) who switched from placebo in the RCP to ravulizumab in the OLE showed rapid improvements in MG-ADL and QMG total scores, which were maintained through 34 weeks: least-squares mean (95% CI) changes from OLE baseline at Week 34 of the OLE (Week 60 from RCP baseline) were -1.7 (-2.7, -0.8; p=0.0007) and -3.1 (-4.2, -1.9; p<0.0001), respectively. Improvements achieved by ravulizumab-treated patients (n=78) in the RCP were sustained through 60 weeks: least-squares mean (95% CI) changes from RCP baseline at Week 60 were -4.0 (-4.8, -3.1; p<0.0001) and -4.1 (-5.4, -2.9; p<0.0001) for MG-ADL and QMG total scores, respectively. Ravulizumab was well tolerated; no meningococcal infections were reported. Four deaths occurred, all assessed by the investigators as unrelated to study treatment. _x000D_ Conclusion:_x000D_ Ravulizumab, administered every 8 weeks, demonstrated sustained improvements in MG symptoms and was well tolerated for up to 60 weeks in adults with AChR Ab+ gMG."