To evaluate the efficacy and safety of efgartigimod in patients with myasthenia gravis (MG) and to determine whether response differs between AChR-positive and AChR-negative subtypes.

MG is an autoimmune neuromuscular disorder caused by IgG antibodies targeting the neuromuscular junction. Efgartigimod, a newly FDA-approved engineered Fc fragment of human IgG1, acts by blocking the neonatal Fc receptor, reducing IgG and pathogenic antibodies.

A comprehensive search was conducted in PubMed, Scopus, Web of Science, and Cochrane CENTRAL databases until September 2025. Studies assessing the efficacy and safety of efgartigimod in MG were included. A random-effects model was used to calculate mean difference (MD) and proportions with corresponding 95% confidence intervals (CIs). Subgroup and sensitivity analyses were conducted. 

Twenty-nine studies (1649 patients) were included. Overall, 83% of patients achieved clinically meaningful improvement (CMI; ≥ 2-point reduction in MG Activities of Daily Living [MG-ADL] score), and 36% achieved minimal symptom expression (MSE; MG-ADL score of 0 or 1) with no significant difference between AChR-positive and AChR-negative subtypes. MG-ADL score significantly decreased from baseline (MD: -4.3 points, 95% CI: -4.99 to -3.61), with no difference between the MG subtypes. Quantitative Myasthenia Gravis score (QMG; MD: -3.6 points, 95% CI: -4.28 to -2.91), Myasthenia Gravis Quality of Life 15-item revised scale (MG-QoL15r; MD: -5.57 points, 95% CI: -6.7 to -4.24), IgG levels (MD: -4.5 gram/litre, 95% CI: -7.02 to -1.99), and corticosteroid use (MD: -6.74 milligram/day, 95% CI: -9.4 to -4.09) showed significant reductions in the AChR-positive subtype, however, these outcomes were not reported in AChR-negative subtype. Serious Adverse events were reported in 6.5% of patients.

Efgartigimod significantly improved clinical symptoms and quality of life in MG patients with no difference between subtypes. Further studies directly comparing efgartigimod with other interventions are needed, regardless of antibody subtype.