Tofacitinib is effective in the treatment of patients with polyarticular-course juvenile idiopathic arthritis (JIA), according to study results published in Lancet.
The aim of the trial was to determine the safety and efficacy of tofacitinib vs placebo in the treatment of polyarticular-course JIA.
In a double-blind, withdrawal, phase 3trial (ClinicalTrials.gov Identifier: NCT02592434), patients aged older than 2 years and younger than 18 years diagnosed with polyarticular-course JIA (extended oligoarthritis, rheumatoid factor (RF)-positive or RF-negative polyarthritis, or systemic JIA without active systemic features) were enrolled across 64 centers in 14 countries.
In the first part of the study, patients received oral open-label tofacitinib (weight-based doses; ≤5 mg twice daily) for 18 weeks. In part 2, patients achieving at least JIA/American College of Rheumatology (ACR) 30 response were randomly assigned 1:1 to continue to receive tofacitinib or switch to placebo for 26 weeks.
The JIA flare rate by week 44 in part 2 of the study in patients with polyarticular-course JIA was the primary endpoint; intention-to-treat principle was applied. During the entire study, safety was evaluated among all patients receiving 1 or more doses.
Overall, among 225 patients enrolled, 184 (82%) had polyarticular-course JIA, 20 (9%) had psoriatic arthritis (PsA), and 21 (9%) had enthesitis-related arthritis. Median disease duration was 2.5 years (IQR, 1.0-5.6 years); 147 (65%) patients received concomitant methotrexate. In part 2 of the study, of 142 patients enrolled, 72 were assigned to receive tofacitinib and 70 to receive placebo.
By week 44, flare rate was significantly lower for patients receiving tofacitinib compared with placebo (29% vs 53%, respectively; hazard ratio, 0.46, 95% CI 0.27-0.79; P =.0031).
Safety was similar among patients with polyarticular-course JIA, PsA, and enthesitis-related arthritis receiving tofacitinib or placebo. Most adverse events were mild. Severe adverse events were observed in 2 (2%) of the 225 patients during the tofacitinib-exposure period, all of which occurred in part 1 of the study. In total, 107 (48%) of the 225 patients had infections or infestations during the entire exposure period, and there were no deaths.
Study limitations included the use of an indirect measure of tofacitinib efficacy and JIA flare. Many patients receiving placebo met the flare criteria in part 2 of the study and discontinued the trial, potentially reducing the observed differences in efficacy. The study population was small and predominantly White, and it was not possible to detect rare adverse events.
Researchers concluded, “These findings suggest a [favorable] benefit-risk balance in patients with polyarticular course JIA treated with oral tofacitinib.” They added, “It will be important to confirm these results in clinical practice and with long-term follow-up.”
Disclosures: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.
Ruperto N, Brunner HI, Synoverska O, et al. Tofacitinib in juvenile idiopathic arthritis: a double-blind, placebo-controlled, withdrawal phase 3 randomised trial. Lancet. 2021;398(10315):1984-1996. doi:10.1016/S0140-6736(21)01255-1