Title: FRI0137 Discontinuation of baricitinib after achieving low disease activity in patients with rheumatoid arthritis in clinical practice; a multicenter observational study.
Abstract: Background: Baricitinib (bari) is an oral Janus kinase (JAK) 1/JAK2 selective inhibitor that has shown good efficacy in patients with RA and adequate response to conventional synthetic DMARDs in some clinical trials [1,2]. However, concerning the high cost and long-term safety related to the inhibition of particular molecules, we would like to discontinue bari after achieving long low disease activity (LDA). Objectives: To evaluate the clinical outcomes in patients with RA who discontinued bari after achieving LDA for 24 weeks in real-world multicenter clinical data. Methods: Japanese 67 patients with RA who show an inadequate response to csDMARDs or bDMARDs were scheduled to receive bari 4 or 2 mg/day once daily dose as a monotherapy or in combination with other csDMARDs. We included 51 patients who achieved and maintained LDA at least for 24 weeks after baricitinib therapy. They were allowed to decrease baricitinib after discontinuation of prednisolone. Bari was either discontinued or continued after study enrolment. The decision of discontinuation and continuation of baricitinib was determined based on patient-physician decision making with informed consent. We divided patients into two groups: a discontinuation group (D group; n = 23) and a continuation group (C group; n = 28). We evaluated the proportion of patients who remained LDA for 24 weeks in both groups. Clinical outcomes including Clinical Disease Activity Index (CDAI), and HAQ-DI were compared between both groups. The last observational carried forward method was used for patients who could not discontinue baricitinib due to flare before 24 weeks. In D group, patients were treated with re-initiation of bari or initiation of the other DMARDs in the event of flare. We investigated the serial changes of patients treated with re-initiation of bari in CDAI after flare. Results: The baseline characteristics of the patients are summarized in Table. The titer of RF was lower in D group than that in C group. There were no significant differences in any other items. Ten of 23 (43.4%) in D group remained bari-free without disease activity flare. Serial changes of CDAI were summarized in Figure. CDAI in D group significantly increased from 3.6 at baseline to 9.8 at last observation. LDA rates in C group were 92.9% at last observation. CDAI in C group did not change throughout the follow-up period. CDAI at last observation was higher in D group than that in C group. HAQ-DI in D group changed from 0.28 at baseline to 0.45 at last observation. There was no significant change in HAQ-DI between both groups (P = 0.28). In D group, rescue by re-administration of bari or other DMARDs induced improvement, reducing CDAI from 15.5 at disease flare to 6.8. Especially, all patients treated with re-initiation of bari resulted in re-introduction of LDA in this study. Table. Characteristics of patients at baricitinib initiation D group (n=23) C group (n=28) p-value Age (years) 66.9 (8.6) 67.9 (12.7) 0.31 Gender, female, n (%) 6 (73.9) 24 (85.7) 0.49 Disease duration (years) 7.6 (10.3) 8.3 (9.9) 0.37 Prior use of biologics, n (0/1/2/≥3) (21/2/0/0) (17/6/4/1) ------ MTX (mg/w) 5.5 (3.8) 4.9 (4.3) 0.62 PSL (mg/d) 1.4 (1.9) 0.9 (0.9) 0.51 RF, U/ml 99 (141) 187 (214) 0.04 ACPA, U/ml 135 (173) 194 (214) 0.11 CDAI 24.4 (9.2) 22.5 (9.7) 0.36 HAQ-DI 0.83 (0.49) 0.83 (0.52) 0.98 Conclusion: It was possible to discontinue bari without flare in about 43% of patients with RA. Overall the patients treated with re-initiation of bari could result in re-introduction of LDA without deterioration of HAQ-DI. References: [1]Tanaka Y et al. Mod Rheumatol. 2018;28:583-91 [2]Tanaka Y et al. Mod Rheumatol. 2018;28:20-9 Disclosure of Interests: Eiji Torikai: None declared, Yuji Hirano Speakers bureau: Tanabe-Mitsubishi, Pfizer, Eisai, Abbie, Chugai, Bristol-Meyers, Jansen, Astellas, UCB, Eli-Lilly, Asahikasei, Daiichi-Sankyo, Amgen, Daisuke Suzuki: None declared, Yasuhide Kanayama: None declared