Radiographic Progression in Psoriatic Arthritis Achieving a Good Response to Treatment: Data Using Newer Composite Indices of Disease Activity.

OBJECTIVE: To compare radiographic outcomes according to the magnitude of the response utilizing 3 new psoriatic composite disease activity measures (the Psoriatic Arthritis Disease Activity Score [PASDAS], the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis Composite Exercise [GRACE], and the Disease Activity in PsA [DAPSA]).

METHODS: The data were taken from the GO-REVEAL data set, a large randomized, double-blind study that evaluated the safety and efficacy of 2 doses of the tumor necrosis factor inhibitor golimumab in subjects with active psoriatic arthritis (PsA). Response criteria at 24 weeks were applied across the whole data set, irrespective of treatment group. Radiographic scores at baseline and 24 weeks were assessed using the modified Sharp/van der Heijde method 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 83% using the PASDAS (χ2 = 7.9; P = 0.02), 80% using the GRACE (χ2 = 5.8; P = 0.05), and 76% using the DAPSA (χ2 = 3.4; P = 0.19).

CONCLUSION: 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.