Comparison of the efficacy and safety of two starting dosages of prednisolone in early active rheumatoid arthritis (CORRA): study protocol for a randomized controlled trial

BACKGROUND: Although glucocorticoids are widely used in the treatment of patients with early rheumatoid arthritis, the best dosage of glucocorticoids with regards to efficacy and safety is not known. The aim of the study ‘Comparison of the efficacy and safety of two starting dosages of prednisolone in early active rheumatoid arthritis’ (CORRA) is to compare two standard glucocorticoid starting dosages and the non-use of glucocorticoids in the treatment of patients with early active rheumatoid arthritis on the background of the established ‘anchor’ therapy with methotrexate. METHODS/DESIGN: CORRA is an investigator-initiated, randomized, multicenter, double-blind, placebo-controlled trial with two treatment arms, starting with 60 mg or 10 mg prednisolone per day, tapered down to 5 mg prednisolone within eight weeks, and one placebo arm, each arm comprising 150 patients. The duration of the intervention is 12 weeks. In parallel, all patients will be treated with methotrexate (usual dosage 15 mg/week). The primary efficacy endpoint is the progression of radiographic joint damage after one year compared to baseline. Important secondary endpoints are the percentage of patients in remission, patient global assessment of disease activity, and changes of functional capacity. Safety monitoring is performed. The statistical analysis is performed in three hierarchical steps. The first step is an analysis of covariance (α = 0.05) to compare the group with the initial prednisolone dosage of 60 mg and the placebo group. In case of a statistically significant result, the comparison of the group starting with 10 mg prednisolone with the placebo group will be performed as a second step (α = 0.05). In case of superiority of the 10 mg prednisolone group versus the placebo group, the third step will be a non-inferiority test for the 10 mg prednisolone group versus the 60 mg prednisolone group (α = 0.025). DISCUSSION: The CORRA trial will yield information concerning the optimal glucocorticoid dosage schedule in the treatment of patients with early rheumatoid arthritis. TRIAL REGISTRATION: This trial was registered on 19 November 2013 at ClinicalTrials.gov. Registration number: NCT02000336.