Early real-life experience on Zilucoplan for generalized myasthenia gravis: ZILU25 multicenter observational study

Abstract

Background and objectives: Generalized Myasthenia gravis (gMG) is a rare chronic autoimmune disease affecting the postsynaptic membrane of the neuromuscular junction. New treatment options, such as the C5 inhibitors, are growing with promising results. In this study we investigated the real-world use of Zilucoplan for AChR-positive gMG in Italy.

Materials and methods: Zilucoplan was self-administered by daily subcutaneous injections. Efficacy was assessed by Myasthenia Gravis Foundation of America Post-intervention status (MGFA-PIS), Myasthenia Gravis Activity of Daily Living (MG-ADL), Myasthenia Gravis Composite (MGC), Myasthenia Gravis quantitative (QMG) scales and 15-items Myasthenia Gravis Quality of Life (MG-QOL-15) questionnaire at baseline and after 1, 4, 12, 24 and 48 weeks.

Results: 54 patients (37 females, aged 57.3) received zilucoplan with a mean follow-up of 26.4 weeks. We observed a clinical meaningful and significant reduction of MG-ADL, QMG, MGC and MG-QOL-15 scores from W4 to W12 and sustained at W24 of follow-up. The MG-ADL responder rate was 75.6 % at W12 and 82.9 % at W24. Minimal symptoms expression (MSE) was obtained in 55.6 % of patients at W48 with a mean reduction of the daily prednisone dose of 8.3 mg at W24. Chronic IVIg was associated to a better response to MG-ADL at W12 at multivariate analysis.

Discussion and conclusions: Zilucoplan was well-tolerated and effective in most patients with AChR-positive gMG. A clinical meaningful effect was reported since the first week and was sustained after 24 weeks. Further studies are needed to confirm these preliminary real-life data.

Keywords: AChR; C5 inhibitor; Complement inhibition; Zilucoplan; myasthenia gravis.