Prednisolone Versus Colchicine for Acute Gout in Primary Care (COPAGO): protocol for a two-arm multicentre, pragmatic, prospective, randomized, double-blind, controlled clinical trial of prednisolone and colchicine for non-inferiority with a parallel group design

Background Gout is the most common form of rheumatic disease in which monosodium urate crystals are deposited in the joints followed by acute inflammatory reactions. There are various approved drugs that can be prescribed for pain relief during an acute gout attack. However, to date, no direct comparison of efficacy of colchicine and prednisolone for the treatment of acute gout attacks has been investigated. Furthermore, the majority of previous research studies were not only conducted in tertiary centres but also excluded patients with common comorbidities due to contraindications to naproxen. Methods This pragmatic, prospective, double-blind, double-dummy, parallel-group, randomized, non-inferiority trial investigates whether prednisolone (intervention) is non-inferior to treatment with colchicine (active control) in patients with acute gout. Adult patients presenting with acute gout to their general practitioners in 60 practices across 3 university sites (Greifswald, Göttingen, and Würzburg) are eligible to participate in the study. Participants in the intervention group receive 30 mg prednisolone for 5 days. Those in the control group receive low-dose colchicine (day 1: 1.5 mg; days 2–5: 1 mg). The primary outcome is the absolute level of the most severe pain on day 3 (in the last 24 h) measured with an 11-item numerical rating scale. Day 0 is the day patients take their study medication for the first time. They are then asked to fill out a study diary the same time each day for pain quantification. Pain scores are used for comparison between the two medications. Secondary outcomes are average response to treatment, swelling, tenderness and physical function of the joint, patients’ global assessment of treatment success, use of additional pain medication and non-pharmacological pain therapies. For safety reasons, potential side effects and course of systolic blood pressure are assessed. Discussion This trial will provide evidence on the effectiveness of pain reduction and side effects of colchicine and prednisolone in acute gout in primary care. Trial registration ClinicalTrials.gov Identifier: NCT05698680 first posted on January 26, 2023 (retrospectively registered). URL of trial registry record: https://clinicaltrials.gov/study/NCT05698680