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OBJECTIVES With the increased use of immune checkpoint inhibitors (ICIs), arthralgia has been the most commonly reported musculoskeletal immune-related adverse events (irAEs). We aimed to characterise arthralgia and its association with overall survival (OS). METHODS Randomised controlled trials (RCTs) reporting data for ICI-induced arthralgia from four online databases were comprehensively investigated. Odds ratios (OR) with 95% confidence intervals (CI) were calculated for arthralgia using a random effects model meta-analysis. Individual patient data were reconstructed from RCTs, assessing OS in patients with or without ICI-induced arthralgia. We also retrospectively collected data on the clinical features and outcomes of ICI-induced arthralgia in the Yokohama City University (YCU) registry. RESULTS We analysed 14,377 patients from 24 RCTs. The OR of ICI-induced arthralgia was 1.37 (95% CI 1.20-1.56). Of the 369 patients in YCU registry, 50 (13.6%) developed ICI-induced arthralgia. Among them, 30 had other grade ≥2 irAEs; noticeably more frequently vs. those without arthralgia (OR 1.92, 95% CI 1.04-3.52). By irAE types, a significant difference was found for relative adrenal insufficiency (OR 3.88, 95% CI 1.80-8.39). In the YCU registry, patients with (vs. without) ICI-induced arthralgia had better OS (log-rank, P < 0.001). OS results were validated from RCT patients with matched cancer types, drugs, and time to arthralgia onset (hazard ratio 0.34, 95% CI 0.17-0.65, P < 0.001). CONCLUSION If arthralgia develops after ICIs, another irAE, such as relative adrenal insufficiency, may have developed. The incidence of arthralgia was associated with better OS and patients' condition must be carefully evaluated to determine optimal management.