Rheumatic Immune-Related AEs With Immune Checkpoint Inhibitors More Severe Than Previously Reported

TUESDAY, Sept. 22, 2026 (HealthDay News) — For patients receiving immune checkpoint inhibitors (ICIs), rheumatic immune-related adverse events (rh-irAEs) are usually moderate or severe, with more than one-third leading to permanent ICI discontinuation, according to a study published online Sept. 8 in ACR Open Rheumatology.

Didzis Gailis, M.D., from the Ludwig-Maximilians-Universität University Hospital in Munich, and colleagues describe clinical phenotypes, treatment, and outcomes of rh-irAEs in a multicenter, observational registry of adults receiving ICIs.

Sixty patients were included as of Jan. 1, 2026; the main malignancy was melanoma (40.0 percent). The researchers found that the leading phenotype was rheumatoid arthritis-like polyarthritis, followed by polymyalgia rheumatica-like and peripheral spondyloarthritis-like syndrome (41.7, 18.3, and 11.7 percent, respectively). Younger patients had axial spondyloarthritis-like syndrome. Ninety percent had moderate or severe rh-irAEs; 23.3 and 38.3 percent required hospitalization and permanently discontinued ICIs, respectively. Eighty-five percent used systemic glucocorticoids (GCs); 58.3 and 53.3 percent were GC-refractory and required second-line immunomodulatory therapy, respectively. Overall, 33.3 and 51.7 percent achieved complete remission and partial remission, respectively. Fifteen percent had oncological progression; 28.1 percent of patients required second-line therapy. The strongest predictor of second-line systemic therapy was male sex.

“Strikingly, 53.3 percent of patients required immunomodulatory therapy beyond GCs,” the authors write. “The therapeutic demand of rh-irAEs, particularly in a rheumatologists-referred setting, is greater than previously reported.”

Several authors disclosed ties to the biopharmaceutical and health care industries.

Abstract/Full Text