Tofacitinib, effective treatment for juvenile idiopathic arthritis: Lancet

USA: Tofacitinib, an oral Janus kinase inhibitor, is effective for the treatment of patients with polyarticular course juvenile idiopathic arthritis (JIA), show findings from a pivotal trial published in The Lancet. The researchers add that new oral therapies may be particularly relevant for those children and adolescents who might prefer to avoid injections. 

Polyarticular juvenile idiopathic arthritis is a subset of juvenile idiopathic arthritis (JIA) that is defined by the presence of more than four affected joints during the first six months of illness. Nicolino Ruperto, IRCCS Istituto Giannina Gaslini, UOSID Centro Trial, PRINTO, Genova, Italy, and colleagues aimed to assess the efficacy and safety of tofacitinib versus placebo in patients with polyarticular course juvenile idiopathic arthritis in a double-blind, placebo-controlled, withdrawal phase 3 randomized trial. 

The trial enrolled patients with polyarticular course JIA (extended oligoarthritis, rheumatoid factor-positive or rheumatoid factor-negative polyarthritis, or systemic JIA without active systemic features) aged 2 years to younger than 18 years. The trika was performed at 64 centres of the Paediatric Rheumatology International Trials Organisation and Pediatric Rheumatology Collaborative Study Group networks in 14 countries. For exploratory endpoints, patients with psoriatic arthritis or enthesitis-related arthritis were enrolled. 

In part 1 of the study, patients received oral open-label tofacitinib (weight-based doses; 5 mg twice daily or lower) for 18 weeks. Patients achieving at least JIA/American College of Rheumatology 30 response were randomly assigned (1:1) to continue tofacitinib or switch to placebo in part 2 of the study for 26 weeks. 

The primary endpoint was JIA flare rate by week 44 in part 2 in patients with polyarticular course JIA; the intention-to-treat principle was applied. Safety was evaluated throughout part 1 and part 2 of the study in all patients who received one dose or more of study medication. 

Of 225 patients enrolled between June 10, 2016, and May 16, 2019, 184 (82%) patients had polyarticular course JIA, 20 (9%) had psoriatic arthritis, and 21 (9%) had enthesitis-related arthritis. 147 (65%) of 225 patients received concomitant methotrexate. In part 2, 142 patients with polyarticular course JIA were assigned to tofacitinib (n=72) or placebo (n=70). 

"The results of this pivotal trial show that tofacitinib is an effective treatment in patients with polyarticular course JIA," wrote the authors.

Reference:

The study titled, "Tofacitinib in juvenile idiopathic arthritis: a double-blind, placebo-controlled, withdrawal phase 3 randomised trial," is published in The Lancet. 

DOI: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)01255-1/fulltext