Efgartigimod in the treatment of severe Guillain-Barre syndrome with overlapping autoantibody syndrome: a case report and updated clinical review.

Guillain-Barre syndrome (GBS) is an immune-mediated acute inflammatory polyradiculoneuropathy, with intravenous immunoglobulin (IVIG) and plasma exchange (PLEX) established as standard first-line treatments. A subset of severe overlapping GBS patients carrying multiple pathogenic anti-ganglioside immunoglobulin G (IgG) antibodies typically exhibits poor therapeutic responses to IVIG. Efgartigimod, a neonatal Fc receptor (FcRn) antagonist, accelerates the clearance of circulating pathogenic IgG, conferring theoretical therapeutic value for IgG-driven autoimmune neurological disorders. Herein, we present a 51-year-old female patient with severe multi-antibody-positive overlapping GBS who failed full-course standard IVIG treatment; sequential salvage Efgartigimod administration induced progressive recovery of limb muscle strength. We further performed a systematic literature review pooling 15 previously published cases of efgartigimod-treated GBS to synthesize global clinical evidence. Our pooled analysis suggests that Efgartigimod could act as a salvage therapeutic candidate for IVIG-refractory severe GBS complicated by multiple anti-ganglioside antibody positivity. Nevertheless, the definitive efficacy and optimal timing of intervention remain to be validated by large‑sample randomized controlled trials.