Safety and outcomes with efgartigimod use for acetylcholine receptor-positive generalized myasthenia gravis in clinical practice. Muscle & nerve Katyal, N., Halldorsdottir, K., Govindarajan, R., Shieh, P., Muley, S., Reyes, P., Leung, K. K., Mullen, J., Milani-Nejad, S., Korb, M., Goyal, N. A., Mozaffar, T., Goyal, N., Habib, A. A., Muppidi, S. 2023

Abstract

Multiple novel therapies have been approved for patients with myasthenia gravis. Our aim is to describe the early experience of efgartigimod use in acetylcholine receptor antibody-positive generalized myasthenia gravis (AChR+ve gMG).This multicenter retrospective study included AChR+ve gMG patients from five major neuromuscular centers who were treated with efgartigimod and had both pre- and post-efgartigimod myasthenia gravis activities of daily living (MG-ADL) scores. Information regarding MG history, concomitant treatment(s), MG-ADL and other MG-specific measures, laboratory data, and adverse events were recorded.A total of 37 patients (M:23, F:14) with a mean age of 65.56 (±14.74) y were included in this cohort. A total of 36/37 patients completed at least one cycle and 28 patients completed at least two cycles of efgartigimod. A total of 72% (26/36) of patients had a clinically meaningful reduction (=2 point change) in MG-ADL after the completion of the first cycle of efgartigimod (mean pre-efgartigimod 8.02) (±3.09) versus post-efgartigimod 4.33 (±3.62). Twenty-five percent (9/36) achieved minimal symptom expression status after one cycle and 25% (7/28) after the second cycle. Treatment benefit was sustained after cycle 2. Three out of four patients with thymoma in this cohort had clinically significant reductions in MG-ADL scores. Immunoglobulin G (IgG) levels decreased by about 60% (n?=?10). One patient had a relapse of Clostridium difficile infection resulting in the discontinuation of therapy. Four patients had mild side effects.Efgartigimod led to clinically meaningful improvement in MG-ADL in diverse AChR+ve gMG patients but treatment frequency to achieve optimal symptom control needs to be explored.

View details for DOI 10.1002/mus.27974

View details for PubMedID 37695277