Comparison between leflunomide and sulfasalazinebased triple therapy in methotrexate refractory rheumatoid arthritis: an open-label, non-inferiority randomized controlled trial.

Abstract

To compare efficacy and safety of two different combination csDMARD therapy in Methotrexate-failed Rheumatoid arthritis patients. In this 24-week open-label, parallel-group non-inferiority, single-center clinical trial, Methotrexate-failed Rheumatoid arthritis patients with disease duration < 2years, were randomized to either of the two treatment regimens-Methotrexate + Leflunomide + Hydroxychloroquine or Methotrexate + Sulfasalazine + Hydroxychloroquine. Primary endpoint was proportion of patients achieving EULAR good response at 12weeks. Non-inferiority of Leflunomide based therapy was confirmed if the upper limit of the 2-sided 95% confidence interval of treatment difference between the 2 groups was lower than the selected non-inferiority margin of (-20%) in primary endpoint at 12weeks. Secondary endpoints were improvement in DAS28, functional outcome and adverse events at 24weeks. 136 eligible patients were randomized to either Leflunomide or Sulfasalazine group (68 in each group).63 and 59 patients in Leflunomide and 66 and 61 patients in Sulfasalazine group completed 12 and 24weeks of trial, respectively. In Intension-to-treat analysis, EULAR good response was achieved by 58.8% and 54.4% patients (p = 0.7) at the end of 12weeks, and 61.7% and 64.7% patients (p = 0.8) at the end of 24weeks-in Leflunomide and Sulfasalazine group respectively. At 12weeks, the difference in EULAR good response with 2-sided 95% confidence interval between 2 groups was 4.4% (-12%, 20%) in intention-to-treat and 5.8% (-11%, 23%) in perprotocol analysis.15 and 21 adverse events were recorded in Leflunomide and Sulfasalazine group respectively. Parenteral Methotrexate was required more in Sulfasalazine group due to gastrointestinal intolerance. Leflunomide based csDMARD therapy is non-inferior to Sulfasalazine based csDMARD therapy in Methotrexate-failed Rheumatoid arthritis patients with comparable safety profile. Trial registered at clinicaltrials.gov (NCT02930343) dated 10.09.2016.