Whole body-MRI identifies widespread, low intensity inflammation in peripheral joints, and axial involvement in a third of patients with early, treatment-naïve, active psoriatic arthritis: Data from the GOLMePsA clinical trial

Objectives To describe the prevalence and extent of whole body (WB)-MRI detected joint disease features and their response to therapy in patients with early, active PsA.

Methods Newly diagnosed PsA patients (treatment-naïve), recruited in GOLMePsA randomized trial (methotrexate plus golimumab and steroids, GOLMTX vs methotrexate plus steroids, PBOMTX), underwent a multi-joint MRI protocol (baseline; week 24 [primary outcome] and week 36). The validated WIPE (peripheral joints and entheses); HIMRISS, KIMRISS (hip and knee); HEMRIS (heel); and CANDEN and SPARCC (sacroiliac joints (SIJs), spine) scores were recorded. Exploratory estimates of difference or ratios (with confidence intervals - CI; 75-95%) between groups at weeks 24 and 36, were obtained using multiple binary logistic or quantile (median) regression.

Results Overall, 93 paired scans from 31 participants (median symptom duration 10.5 months; IQR 4.2-18.3; absolute range 1.8-197.7; 68% polyarticular) were included. Baseline scores showed widespread low intensity inflammation in peripheral tissues (median MRI-WIPE score: 37 – CI 19.0-55.0). SIJs and spine inflammation (SPARCC score ≥2) was seen in 25.8% (10/31) and 32.3% (10/31), respectively. Participants achieved median MRI-WIPE delta (the difference between time-points) of -10 at week 24 and -7 at week 36 in the GOLMTX and -6 and -9 in PBOMTX arms respectively. No differences between treatment groups were observed.

Conclusions In this exploratory analysis, WB-MRI identified widespread although low intensity inflammation in peripheral joints and enthesis with improvements seen at 24 and 36 weeks and no meaningful differences between treatment arms. Axial abnormalities were seen in one third of patients at baseline.