Comparative efficacy of single-cycle intravenous efgartigimod versus intravenous immunoglobulin in generalized myasthenia gravis patients receiving concomitant immunosuppressive therapy.

Comparative evidence between efgartigimod and intravenous immunoglobulin (IVIg) in generalized myasthenia gravis (gMG) remains limited, especially regarding outcomes beyond the first month. We evaluated the 6-month efficacy and safety of single-cycle intravenous efgartigimod versus IVIg in 51 patients with moderate-to-severe gMG (efgartigimod: 26; IVIg: 25) receiving concomitant immunosuppressive therapy in a real-world setting. At month 1, significantly more efgartigimod-treated patients achieved the primary endpoint of minimal symptom expression (MSE) without intensive immunotherapy (42.3% vs. 12.0%; P = 0.023). Efgartigimod also demonstrated greater reductions in MG Activities of Daily Living scores at month 1 compared with IVIg (adjusted mean difference, -2.37; 95% CI, -3.99 to -0.74; P = 0.004). The median time to MSE was significantly shorter in the efgartigimod group (2.1 vs. 5.9 months; Breslow P = 0.030). However, clinical differences became non-significant at months 3 and 6. Rates of disease relapse or exacerbation remained comparable between groups. Both treatments were well tolerated. In conclusion, single-cycle intravenous efgartigimod was associated with faster early clinical improvement compared with IVIg, while outcomes were comparable at months 3 and 6 in the context of real-world immunosuppressive therapies. These findings suggest that efgartigimod may represent an alternative therapeutic option for patients with gMG requiring rapid symptom control.