Imaging in clinical trials of rheumatoid arthritis: where are we in 2025?

Accurate detection and assessment of inflammatory activity is crucial not only for diagnosing patients with rheumatoid arthritis but also for effective monitoring of treatment effect. Ultrasound and magnetic resonance imaging (MRI) have both been shown to be truthful, reproducible, and sensitive to change for inflammation in joints and tendon sheaths and have validated scoring systems, which altogether allow them to be used as outcome measurement instruments in clinical trials. Furthermore, MRI also allows sensitive and discriminative assessment of structural damage progression in RA, also with validated outcome measures. Other relevant imaging techniques, including the use of artificial intelligence, pose interesting possibilities for future clinical trials and will be briefly addressed in this review article.