Real-world experience with efgartigimod in generalized myasthenia gravis: a single-center retrospective study in China.

OBJECTIVE

This study aimed to evaluate the real-world efficacy, safety, and application patterns of efgartigimod in Chinese patients with generalized myasthenia gravis (gMG), with a focus on individualized treatment strategies.

METHODS

We conducted a single-center, retrospective analysis of 81 gMG patients who received at least one standard cycle of efgartigimod (10 mg/kg weekly for 4 weeks). Disease severity was assessed using Myasthenia Gravis Activities of Daily Living (MG-ADL), Quantitative Myasthenia Gravis (QMG), and Myasthenia Gravis Composite (MGC) scores at baseline, week 2, and week 4. Retreatment and regimen modifications were individualized, which included exploration of a reduced-frequency regimen (2 infusions every 2 weeks) in selected patients.

RESULTS

In the overall cohort, 65 (80.25%) and 63 (77.78%) patients achieved MG-ADL (reduction ≥2) and QMG (reduction ≥3) responses, respectively, after the first cycle. 65 (80.25%) patients received only one cycle; among them, 41 (63.07%) maintained disease control with concomitant immunosuppressive therapies without requiring additional efgartigimod. The 16 patients receiving multiple cycles (≥2) had higher baseline disease severity (higher Myasthenia Gravis Foundation of America class, MG-ADL, and QMG scores) and showed progressive improvement with flexible retreatment. In a selected subgroup of 9 patients (based on age, robust response, and significant IgG reduction), a reduced-frequency regimen (2 infusions every 2 weeks) maintained efficacy while reducing the infusion burden. Adverse events were mostly mild, with no new safety signals.

INTERPRETATION: Efgartigimod demonstrated rapid and broad efficacy in a real-world gMG cohort. An "induction-maintenance" strategy, using efgartigimod for acute control and conventional immunosuppressants for long-term management, proved effective in most patients. A reduced-frequency regimen may be feasible in selected cases, highlighting the value of individualized treatment approaches in optimizing outcomes and reducing treatment burden.