Efficacy and safety of baricitinib in Japanese patients with rheumatoid arthritis: Subgroup analyses of four multinational phase 3 randomized trials

• Published in: Modern rheumatology Vol. 28; no. 4; pp. 583 - 591
• Main Authors: Tanaka, Yoshiya, Atsumi, Tatsuya, Amano, Koichi, Harigai, Masayoshi, Ishii, Taeko, Kawaguchi, Osamu, Rooney, Terence P., Akashi, Naotsugu, Takeuchi, Tsutomu
• Format: Journal Article
• Language: English
• Published: United States Taylor & Francis 04.07.2018
• Subjects: Baricitinib; Janus kinase (JAK); Japanese; phase 3 clinical trials; rheumatoid arthritis; Janus kinase (JAK); Japanese; rheumatoid arthritis; Baricitinib; phase 3 clinical trials
• ISSN: 1439-7595; 1439-7609
• DOI: 10.1080/14397595.2017.1392057

Objectives: To evaluate efficacy/safety of baricitinib for rheumatoid arthritis (RA) in Japanese subpopulations from four phase 3 studies, and assess whether results in these subpopulations are consistent with the overall study populations. Methods: Subgroup analyses (394 patients) of four phase 3 randomized controlled trials: RA-BEGIN [no or limited treatment with disease-modifying antirheumatic drugs (DMARDs)], RA-BEAM [inadequate response (IR) to methotrexate], RA-BUILD [IR to conventional synthetic DMARDs (csDMARDs)], and RA-BEACON (IR to tumor necrosis factor inhibitors receiving csDMARDs). Results: For American College of Rheumatology 20% improvement (ACR20) response rate, Japanese patients receiving baricitinib 4-mg showed similar improvement compared to methotrexate at Week 24 (72 versus 69%; RA-BEGIN), and greater improvement compared with placebo at Week 12 (67 versus 34%; RA-BEAM). Japanese patients receiving baricitinib 4-mg also showed greater improvement compared with placebo at Week 12 in RA-BUILD and RA-BEACON. Across all studies, baricitinib was well-tolerated, with no deaths and one malignancy. In RA-BEGIN and RA-BEAM, herpes zoster rates were higher for Japanese patients than for overall populations; all events were mild/moderate. Conclusion: Data for baricitinib, with/without methotrexate, in Japanese subpopulations across all stages of the RA treatment continuum accord with the efficacy/safety profile in overall study populations. Baricitinib appears to be similarly effective in Japanese patients.