Precision and cellular therapies for adult idiopathic inflammatory myopathies: Recent advances

Idiopathic inflammatory myopathies (IIMs) are a heterogeneous group of autoimmune diseases with variable extramuscular involvement and diverse treatment responses. Although glucocorticoids and conventional immunosuppressants remain the cornerstone of therapy, refractory disease and treatment intolerance are still common. Emerging biologic, pathway-based, and cellular therapies are expanding treatment options, particularly for selected patients with refractory disease, although the strength of evidence and current clinical applicability vary among approaches. Meanwhile, advances in single-cell and spatial omics are improving understanding of disease heterogeneity and facilitating more precise treatment stratification. This review summarizes current and emerging therapies for adult IIMs, with an emphasis on their clinical relevance, phenotype-specific application, and the evolving role of biomarker-informed precision medicine in refractory disease.