Efficacy of innovative therapies in myasthenia gravis: A systematic review, meta-analysis and network meta-analysis

Background and purpose: Therapy for myasthenia gravis (MG) is undergoing a profound change, with new treatments being tested. These include complement inhibitors and neonatal Fc receptor (FcRn) blockers. The aim of this study was to perform a meta-analysis and network meta-analysis of randomized and placebo-controlled trials of innovative therapies in MG with available efficacy data.

Methods: We assessed statistical heterogeneity across trials based on the Cochrane Q test and I² values, and mean differences were pooled using the random-effects model. Treatment efficacy was assessed after 26 weeks of eculizumab and ravulizumab, 28 days of efgartigimod, 43 days of rozanolixizumab, 12 weeks of zilucoplan, and 16, 24 or 52 weeks of rituximab treatment.

Results: We observed an overall mean Myasthenia Gravis-Activities of Daily Living scale (MG-ADL) score change of -2.17 points (95% confidence interval [CI] -2.67, -1.67; p < 0.001) as compared to placebo. No significant difference emerged between complement inhibitors and anti-FcRn treatment (p = 0.16). The change in Quantitative Myasthenia Gravis scale (QMG) score was -3.46 (95% CI -4.53, -2.39; p < 0.001), with a higher reduction with FcRns (-4.78 vs. -2.60; p < 0.001). Rituximab did not significantly improve the MG-ADL (-0.92 [95% CI -2.24, 0.39]; p = 0.17) or QMG scores (-1.9 [95% CI -3.97, 0.18]; p = 0.07). In the network meta-analysis, efgartigimod had the highest probability of being the best treatment, followed by rozanolixizumab.

Conclusion: Anti-complement and FcRn treatments both proved to be effective in MG patients, whereas rituximab did not show a significant benefit for patients. Within the limitations of this meta-analysis, including efficacy time points, FcRn treatments showed a greater effect on QMG score in the short term. Real-life studies with long-term measurements are needed to confirm our results.