Indirect Comparison of Nipocalimab Versus Efgartigimod and Rozanolixizumab in the Treatment of Generalized Myasthenia Gravis

INTRODUCTION: Nipocalimab, efgartigimod, and rozanolixizumab (the last two cyclically dosed) are approved neonatal Fc receptor (FcRn) blockers for treating generalized myasthenia gravis (gMG). No trials have directly compared these therapies; hence, indirect treatment comparisons (ITCs) were conducted to evaluate their relative efficacy. METHODS: Matching-adjusted indirect comparisons (MAICs) and Bucher ITCs were used to compare nipocalimab vs. efgartigimod and rozanolixizumab for changes from baseline (CFB) in Myasthenia Gravis Activities of Daily Living (MG-ADL) total score observed in their phase 3 registration trials. Bucher ITCs used the relative treatment effect vs. placebo. As there was considerable cross-trial heterogeneity, including uncertainty in using the placebo arm as a common comparator, active treatment arms were used in unanchored MAICs. MG-ADL CFB was compared between trials (1) at multiple timepoints to evaluate onset of action and disease control over time, and (2) using area under the curve (AUC) as a measure of cumulative effect normalized per week of follow-up. RESULTS: In both Bucher ITCs and MAICs, nipocalimab had a comparable MG-ADL CFB at week 1 vs. the other FcRn blockers. In MAICs, MG-ADL CFB was significantly greater with nipocalimab vs. efgartigimod at week 8 sustained up to 24 weeks (p < 0.05), and vs. rozanolixizumab at week 10 sustained up to 14 weeks (p < 0.05); results numerically favored nipocalimab in corresponding Bucher ITCs. Using normalized AUC, MG-ADL CFB with nipocalimab was significantly greater in MAICs (p < 0.05) and numerically greater in Bucher ITCs vs. the other FcRn blockers. CONCLUSIONS: Sustained disease control is an important consideration in managing chronic diseases with fluctuating symptoms such as gMG. Study results showed that nipocalimab provided a comparable onset of action and consistent and sustained disease control that was numerically or statistically significantly greater (depending on ITC method) when compared with the symptom-based cyclic FcRn blockers efgartigimod and rozanolixizumab.