The efficacy, safety and cost-effectiveness of hydroxychloroquine, sulfasalazine, methotrexate triple therapy in preventing relapse among patients with rheumatoid arthritis achieving clinical remission or low disease activity: the study protocol of a randomized controlled clinical Trial (ESCoRT study)

BACKGROUND: Tumor necrosis factor α inhibitors (TNFi) is effective for rheumatoid arthritis (RA) patients who fail to conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs). Because of high cost, the discontinuation is common but often lead to disease relapse. The study aims to investigate, if the combination therapy of csDMARDs is more effective in reducing disease relapse than methotrexate (MTX) monotherapy, and more cost-effective than continuing TNFi and MTX. METHODS: It will be a two-stage trial. In the first stage, all RA patients who failed to csDMARDs treatment [disease activity score 28 (DAS28)-CRP > 3.2] will receive MTX plus TNFi for no more than 12 weeks. Patients achieving DAS28-CRP < 3.2 during the first stage will be randomized into three groups at 1:1:1 ratio: (A) add hydroxychloroquine (HCQ) and sulfasalazine (SSZ) for the first 12 weeks and then remove TNFi but continue other treatments for the next 48 weeks; (B) maintain TNFi + MTX for 60 weeks; and (C) maintain TNFi + MTX for the first 12 weeks and then remove TNFi but continue MTX monotherapy for the next 48 weeks. The primary outcome will be disease relapse (DAS28-CRP increases by at least 0.6 and > 3.2). Secondary outcomes will include the incremental cost per reducing 1 case of relapse; patient reported intolerance to the treatment; adverse events; change of mean disease activity measured by DAS28, clinical disease activity index (CDAI) and simplified disease activity index (SDAI); the proportion of modified Sharp score increase < 0.3; ultrasound-detected remission in hands; Health Assessment Questionnaire Disability Index (HAQ-DI) and health related quality of life [the five-level EuroQol-5D (EQ-5D-5L) and short form-6D (SF-6D)]. DISCUSSION: The aim of this trail will be to seek effective treatment options of preventing relapse of RA. The results of the current study may provide an instructive recommendation for more economical application of TNFi treatment in RA. Trial registration NCT, NCT02320630. Registered on 16 December 2014. https://register.clinicaltrials.gov/prs/app/action/LoginUser?ts=3&cx=-jg9qo2.