Front Immunol. 2026 Jul 15;17:1818836. doi: 10.3389/fimmu.2026.1818836. eCollection 2026.
ABSTRACT
BACKGROUND: A subset of cancer patients receiving monoclonal antibody PD-1/PD-L1 inhibitors may develop immune checkpoint inhibitor (ICI)-related neurological complications, such as ICI-related myasthenia gravis(MG)-myositis overlap syndrome and ICI-related myocarditis. Standard management typically involves intravenous immunoglobulin (IVIG), plasma exchange (PE), and high-dose corticosteroids. The use of efgartigimod, a neonatal Fc receptor blocker, for the treatment of ICI-related MG-myositis overlap syndrome remains investigational, with only four relevant cases all representing overlap syndromes (MG with myositis, with or without myocarditis) - reported to date.
OBJECTIVE: This report examines the therapeutic effect of efgartigimod in a patient with cervical cancer who developed ICI-related MG-myositis overlap syndrome after receiving tislelizumab, an anti-PD-1 antibody.
METHODS: Clinical data from the patient was collected. Relevant laboratory tests and examinations were conducted. Efgartigimod treatment was administered, and clinical severity was evaluated using standardized assessment scales.
RESULTS: A 69-year-old female with cervical cancer developed bilateral ptosis, dysarthria, and limb weakness following tislelizumab therapy. Examination revealed asymmetric ptosis, weak eye closure, and positive fatigability test. Serum creatine kinase was markedly elevated (553.82 U/L); electromyography showed myopathic changes with fibrillation potentials, while repetitive nerve stimulation was negative. Neostigmine test was positive, and anti-acetylcholine receptor antibodies were detected. She was diagnosed with ICI-related MG-myositis overlap syndrome. After four infusions of efgartigimod (10 mg/kg), creatine kinase normalized, the Activities of Daily Living (ADL) score decreased from 10 to 1, and the Quantitative Myasthenia Gravis (QMG) score improved from 16 to 5. The patient was asymptomatic at the 5 months follow-up with no need for a second treatment cycle.
CONCLUSION: Efgartigimod produced a positive therapeutic effect in this case with ICI-related MG-myositis overlap syndrome. The therapy was well-tolerated, and no adverse events were reported.
PMID:42529120 | PMC:PMC13415994 | DOI:10.3389/fimmu.2026.1818836