POS0668 REAL WORLD EFFECTIVENESS OF BARICITINIB IN THE SWISS RHEUMATOID ARTHRITIS REGISTER (SCQM-RA)

Abstract

Background: When not responding to conventional synthetic DMARDs (csDMARDs), rheumatoid arthritis (RA) patients may receive biological DMARDs (bDMARDs) or targeted synthetic DMARDs (tsDMARDs) including baricitinib (BARI). While BARI has demonstrated efficacy in randomized controlled trials, limited studies have established comparative effectiveness in real world settings, in particular when used in b/tsDMARD-naive patients. Objective(s): To analyze the effectiveness of BARI versus alternative bDMARDs, as assessed by drug maintenance over time and by response rates at 12 months. Method(s): This is a nested study of RA patients, within the prospective Swiss Clinical Quality Management (SCQM) observational cohort. All treatment courses (TC) with BARI or alternative bDMARDs initiated between 2017-09-01 and 2020-06-01, with at least one follow-up visit, were included. TC with BARI were compared to TC with alternative bDMARDs (non-BARI), including all b/tsDMARDs except rituximab. The non-BARI group was then subdivided into TNF inhibitors (TNFi) and other mode of action bDMARDs (OMA), excluding tsDMARDs. A secondary analysis focusing specifically on b/tsDMARD naive patients was conducted. Baseline characteristics were compared using ANOVA or chi2 tests. A Cox-model survival analysis assessed drug maintenance. 12-month response rates were estimated using an attrition-corrected, confounder-adjusted approach (1). CDAI score < 0.001). Drug maintenance was also numerically shorter for the OMA group compared to BARI, but the difference was not significant (HR 1.18 (95% CI [0.87 -1.60]); p = 0.28). These differences were larger when analysing only bDMARD-naive patients (Figure 1a). All TC taken together, the rates of LDA and remission did not differ significantly between the 3 groups at 12 months. LDA ranged from 63% to 67% (BARI vs OMA p = 0.87; BARI vs TNFi p = 0.81) and remission from 19% to 23% (BARI vs OMA p = 0.30; BARI vs TNFi p = 0.77; Figure 1b). Conclusion(s): BARI demonstrated a significantly higher overall drug maintenance than TNFi, and a similar drug maintenance to OMA, both in a bDMARD-naive population and in the overall population. The adjusted 12-month response rates did not differ between BARI, TNFi and OMA groups. These results suggest that prescription of BARI after csDMARD has at least similar outcomes as alternative bDMARDs.