Abstract
Immune checkpoint inhibitors (ICIs) play a crucial role in cancer therapy by enhancing anti-tumor immune responses. However, they may also induce immune-related adverse events (irAEs) such as polyradiculoneuropathy (PRN) and cardiomyopathy, which, although rare, can be life-threatening. Traditional treatments, including corticosteroids and intravenous immunoglobulin (IVIG), often show limited efficacy, underscoring the need for alternative therapeutic strategies. The present study reported the case of a 63-year-old female diagnosed with pancreatic ductal adenocarcinoma who developed profound neurological and cardiac dysfunction, including bilateral ptosis, limb weakness and dysphagia, following chemotherapy and ICI therapy. Initial immunotherapy with IVIG and corticosteroids resulted in only partial clinical improvement. Subsequent administration of efgartigimod induced significant neurological recovery, with normalization of both the Inflammatory Neuropathy Cause and Treatment disability score and Activities of Daily Living scale following four weekly doses. Clinical improvement was accompanied by reductions in both cytokine and immunoglobulin levels. This case illustrates the therapeutic potential of efgartigimod in managing ICI-induced PRN and cardiomyopathy, particularly in patients refractory to standard therapies. The observed improvements suggest that antibody-mediated pathways may play a pivotal role in the pathogenesis of irAEs. Further studies are warranted to confirm the efficacy and safety of efgartigimod in alleviating ICI-related irAEs in broader clinical settings.