Baricitinib In The Bsrbr-Ra Registry: Characteristics And Status Of Patients At First Follow-Up

Abstract Background/Aims Baricitinib is a once-daily orally administered Janus kinase (JAK)-inhibitor approved for the treatment of moderate-to-severe active rheumatoid arthritis (RA). The British Society for Rheumatology Biologics Registry-RA (BSRBR-RA) captures real-world data on biologic (b) and targeted synthetic (ts) disease-modifying antirheumatic drugs (DMARDs), including baricitinib, in the UK. Patients are followed up 6-monthly for the first 3 years and annually thereafter. Objectives of this study were to describe baseline characteristics and status (continuation with baricitinib and disease activity) at first follow-up after initiating baricitinib. Analysis was performed independently of the register study team at BSRBR-RA. Methods The study included patients initiating baricitinib and registered in the BSRBR-RA baricitinib cohort between 1 January 2018 and 31 March 2019. Continuation with baricitinib and disease activity score for 28-joint count with erythrocyte sedimentation rate (DAS28-ESR) were assessed in those completing first follow-up at 6 months in the overall population and in the following subgroups: without prior b/tsDMARD experience; with prior b/tsDMARD experience; and receiving baricitinib monotherapy. Continuation was summarised as N (%) remaining on baricitinib at first follow-up (interruptions ≤28 days were permitted). Results During the study period, 409 patients enrolled in the baricitinib cohort. Most were female (76%), the mean disease duration was 13 years (standard deviation [SD] 10) and most had received a prior biologic (63%). Mean and median DAS28-ESR were 5.6 (SD 1.2) and 5.7 (interquartile range 5.1-6.4), respectively. Thirty-nine percent were on baricitinib monotherapy. Overall, 16% were on baricitinib 2mg, 84% on 4mg and 30% were receiving concomitant corticosteroids. First follow-up data were available for 163 patients, of whom 122 (75%) remained on baricitinib. DAS28-ESR was lower at first follow-up than at baseline both overall and in all subgroups (Table 1). Conclusion In an RA study population with severe longstanding disease, in which almost two thirds had received biologics, baricitinib showed good effectiveness and tolerability (continuation) in patients completing first follow-up. Although sample sizes were small, subgroup results suggested good baricitinib effectiveness in all subgroups studied. Further analyses are needed to assess longitudinal outcomes in larger sample sizes at follow-ups beyond 6 months. Disclosure C.J. Edwards: Honoraria; Abbvie, BMS, Biogen, Celgene, Fresenius, Gilead, GSK, Janssen, Lilly, Pfizer, MSD, Novartis, Roche, Samsung, Sanofi, UCB. Member of speakers’ bureau; Abbvie, BMS, Biogen, Celgene, Fresenius, Gilead, GSK, Janssen, Lilly, Pfizer, MSD, Novartis, Roche, Samsung, Sanofi, UCB. Grants/research support; Abbvie, Biogen. J. Mount: Other; Employee at Eli Lilly and Company. A. Meeks: Other; Contractor at Eli Lilly and Company. L. Zaremba-Pechmann: Other; Contractor at Eli Lilly and Company. A. Mian: Other; Employee at Eli Lilly and Company. E. Larsson: Other; Employee at Eli Lilly and Company. E. Dennision: Other; Lilly, Pfizer and UCB.