Analysis of relapse rates and risk factors of tapering or stopping pharmacologic therapies in axial spondyloarthritis patients with sustained remission

The objectives of this study are to evaluate whether tapering or stopping strategies of pharmacologic therapies are efficacious for maintaining remission in patients with axial spondyloarthritis (axSPA) and to analyze the risk factors of disease relapse. Patients diagnosed as axSPA with ankylosing spondylitis disease activity score based on C reactive protein (ASDAS-CRP) ≤2.0 for at least 3 months were randomized into three groups: continuing non-steroidal anti-inflammatory drugs (NSAIDs) and disease-modifying antirheumatic drugs (DMARDs) (group 1), tapering NSAIDs and DMARDs by 50% (group 2), or discontinuing NSAIDs and DMARDs (group3) after 6 months of tapering. The primary endpoint of observation was disease relapse or sustained remission till 12 months. One hundred and eight patients were analyzed in this study. All patients fulfilled ASDAS remission criteria at baseline. Other than NSAIDs therapy, 63.0% of the patients received sulfasalazine, 33.3% biological DMARDs, and 19.4% other DMARDs. Overall, 87 patients (80.6%) remained in remission for 12 months, whereas 21 patients (19.4%) relapsed at the end of the study. There were significant differences of relapse rates among three different study groups (group 1, 5.4%; group 2, 13.2%; group 3, 42.7%; p<0.001), while no significant difference was found between group 1 and group 2 (p=0.430). Multivariate logistic regression identified high ASDAS-CRP at baseline (p=0.001) and drug discontinuation (p<0.001) as predictors for relapse. This randomized controlled study demonstrated that tapering NSAIDs and DMARDs by 50% in patients with axSPA in sustained remission is a feasible treatment strategy. Besides, disease relapse may be related with ASDAS-CRP before treatment tapering.