BACKGROUND Tumour necrosis factor inhibitors (TNFi) are effective in the treatment of patients with spondyloarthritis (SpA), including psoriatic arthritis (PsA) and axial spondyloarthritis (axSpA). However, these drugs come with some disadvantages such as adverse events, practical burden for patients and high costs. Dose optimisation of TNFi after patients have reached low disease activity (LDA) has been shown feasible and safe in rheumatoid arthritis (RA). However, data on TNFi dose optimisation in PsA and axSpA are scarce, especially pragmatic, randomised strategy studies. METHODS We developed an investigator-driven, pragmatic, open-label, randomised, controlled, non-inferiority trial (DRESS-PS) to compare the effects of a disease activity-guided treat-to-target strategy with or without a tapering attempt in patients with SpA (PsA and axSpA combined), ≥ 16 years of age, who are being treated with TNFi, and have had at least 6 months of low disease activity. The primary outcome is the percentage of patients in LDA after 12 months of follow up. Patients are assessed at baseline, 3, 6, 9, and 12 months of follow up. Bayesian power analyses with a weakened prior based on a similar study performed in RA resulted in a sample size of 95 patients in total. DISCUSSION More knowledge on disease activity-guided treatment algorithms would contribute to better treatment choices and cost savings and potentially decrease the risk of side effects. In this article we elucidate some of our design choices on TNFi dose optimisation and its clinical and methodological consequences. TRIAL REGISTRATION Dutch Trial Register, NL6771. Registered on 27 November 2018 (CMO NL66181.091.18, 23 October 2018).

中文翻译：

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银屑病关节炎和轴向性脊柱关节炎的TNF抑制剂的减量和停药策略：实用，开放，随机，非劣效性试验的设计。

背景技术肿瘤坏死因子抑制剂（TNFi）可有效治疗包括银屑病关节炎（PsA）和轴向性脊柱关节炎（axSpA）在内的脊柱关节炎（SpA）患者。然而，这些药物具有一些缺点，例如不良事件，患者的实际负担和高成本。已经证明患者达到低疾病活性（LDA）后的TNFi剂量优化在类风湿关节炎（RA）中是可行且安全的。但是，关于PsA和axSpA中TNFi剂量优化的数据很少，尤其是实用的随机策略研究。方法我们开发了研究者驱动，务实，开放标签，随机，对照，非劣效性试验（DRESS-PS），用于比较以疾病活动为指导的从治疗到靶向策略在不超过16岁的SpA患者（PsA和axSpA合并）中进行或不进行渐进尝试的效果正在接受TNFi治疗，并且至少有6个月的低病情。主要结局是随访12个月后LDA患者的百分比。在基线，3、6、9和12个月的随访中对患者进行评估。基于在RA中进行的类似研究的先验减弱的贝叶斯功效分析导致总共95名患者的样本量。讨论有关疾病活动指导的治疗算法的更多知识将有助于更好的治疗选择和节省成本，并有可能降低副作用的风险。在本文中，我们阐明了关于TNFi剂量优化及其临床和方法学后果的一些设计选择。试用注册荷兰试用注册号NL6771。2018年11月27日注册（CMO NL66181.091.18，2018年10月23日）。