The use of eculizumab in ventilator‐dependent myasthenia gravis patients

Abstract Introduction/Aims Eculizumab has been shown to be efficacious in acetylcholine receptor antibody–positive (AChR + ) Myasthenia Gravis Foundation of America (MGFA) class II, III, and IV generalized myasthenia gravis (gMG) patients. However, it has not been studied in MGFA class V gMG patients. Methods We report three AChR + , refractory, MGFA class V gMG patients treated with eculizumab. MGFA class, MG‐Composite (MGC) score and MG Activities of Daily Living (MG‐ADL) score were assessed before and after eculizumab. Results Two of three gMG patients, refractory to intravenous immunoglobulin, plasmapheresis, prednisone, and (in one case) rituximab, showed a robust response to eculizumab with marked improvement in MGFA, MG‐ADL, and MGC measures. The third patient showed a partial response to eculizumab but remained on noninvasive ventilation and gastrostomy intubation. Patients 1 and 2 achieved minimal manifestation status at week 4 and week 6, respectively, and showed continued improvement on MG‐ADL and MGC scores through weeks 55 and 43, respectively, with eculizumab. The third patient showed a partial response at week 10, followed by a slight decline in his MG‐ADL score, but noted a slow but an incomplete improvement afterward on MG‐ADL and MGC scores, possibly due to delayed eculizumab infusion. Discussion Eculizumab may play a role in the treatment of patients with MGFA class V, refractory gMG. Larger studies are required to provide further evidence.