Radiographic progression is less in psoriatic arthritis achieving a good response to treatment: data using newer composite indices of disease activity

Objectives: The purpose of this study was to compare radiographic outcomes according to the magnitude of the response utilizing three new psoriatic composite disease activity measures (the Psoriatic Arthritis Disease Activity Score (PASDAS), the GRAPPA Composite Exercise (GRACE), and the Disease Activity in PsA (DAPSA). The data were taken from the GO-REVEAL dataset, a large randomised, double-blind, study which evaluated the safety and efficacy of 2 doses of the TNF inhibitor golimumab in subjects with active PsA. Methods: Response criteria at 24 weeks were applied across the whole dataset, irrespective of treatment group. Radiographic scores at baseline and 24 weeks were assessed using the Sharp van der Heijde method, modified for PsA. Results: Overall, for each measure, radiographic progression was significantly greater in subjects with a moderate or poor outcome, and absent in those with a good outcome. The proportion of subjects without radiographic progression in the good outcome group was: PASDAS, 83%, χ2 = 7.9, p = 0.02; GRACE, 80%, χ2 = 5.8, p = 0.05; DAPSA, 76% χ2 = 3.4, p = 0.19. Conclusions: Response criteria for disease specific composite measures enable separation between groups in terms of radiographic progression and may therefore be used as suitable targets for interventional studies, as well as in the clinic.