Comparative Efficacy of Rozanolixizumab with Efgartigimod or Intravenous Immunoglobulin in Generalized Myasthenia...

Generalized myasthenia gravis (gMG) is a rare autoimmune disorder affecting neuromuscular transmission. New targeted treatments including FcRn antagonists have emerged, but direct comparative evidence is lacking. This study aimed to compare the efficacy of rozanolixizumab with efgartigimod or intravenous immunoglobulin (IVIg) using matching-adjusted indirect comparisons (MAICs).

Phase 3 studies of rozanolixizumab and efgartigimod were identified through a literature review. MAICs compared rozanolixizumab (7 mg/kg and 10 mg/kg) with efgartigimod 10 mg/kg IV and IVIg. Anchored comparisons (rozanolixizumab vs. efgartigimod) and unanchored comparisons (rozanolixizumab vs. IVIg) were used. Propensity score weighting balanced covariates between trial populations. Continuous outcomes were analysed using linear regression, and logistic regression for dichotomous outcomes. Treatment effects were presented as mean differences or odds ratios with 95% confidence intervals (CI). Scenario analyses were performed.

Rozanolixizumab efficacy was comparable to efgartigimod except for Quantitative Myasthenia Gravis (QMG) and Myasthenia Gravis Composite (MGC) scores at 6 weeks which were significantly in favour of rozanolixizumab 10 mg/kg (QMG mean difference - 2.80; 95% CI - 5.00, - 0.60; MGC mean difference - 3.89; - 6.72, - 1.05). Both rozanolixizumab doses significantly improved QMG scores from baseline at 2 weeks vs. IVIg (7 mg/kg: - 1.95; - 3.79, - 0.11; 10 mg/kg: - 1.99; - 3.71, - 0.26) and 4 weeks (7 mg/kg: - 3.40; - 5.23, - 1.56; 10 mg/kg: - 3.99; - 5.81, - 2.17). QMG responders at 2 weeks were not significantly different for rozanolixizumab vs. IVIg.

Without direct comparative evidence, these analyses provide additional context to inform treatment decisions for the management of gMG. These analyses suggest that FcRn inhibitors represent important targeted treatment options for gMG.