Background: Eculizumab is a humanized monoclonal antibody that selectively targets the human complement C5 protein, inhibiting terminal complement activation. It is approved for the treatment of refractory generalized myasthenia gravis (gMG) associated with anti-acetylcholine receptor (AChR) antibody positivity. However, real-life data on the steroid-sparing effect of Eculizumab in patients with gMG are limited. The aim of this study is to examine the efficacy of eculizumab on steroid tapering in patients with AChR-positive refractory gMG.
Methods: We identified eight patients with AChR-positive refractory gMG who had been on oral steroids and underwent treatment with eculizumab for at least six months. Steroid tapering was assessed by comparing the dosage at the six-month follow-up to the baseline before the first eculizumab infusion.
Results: Five out of eight patients tapered their steroid dose from a median of 38 (range: 18.75–50) mg/day before starting eculizumab to 18.25 (12.5–31.25) mg/day at the six-month follow-up. Among these, three patients were also receiving additional immunosuppressive therapies. Two patients maintained a stable dose of oral steroids at a median of 10 (5-15) mg/day and were able to discontinue periodic intravenous immunoglobulin infusions. Only one patient required an increase in steroid dosage due to a poor response to eculizumab.
Conclusions: Eculizumab was effective in reducing steroid dosage in most patients with AChR-positive refractory gMG. This suggests a potential role for eculizumab as steroid-sparing drug in patients with refractory gMG.