Efficacy and safety data based on historical or pre-existing conditions at baseline for patients with active rheumatoid arthritis who were treated with baricitinib

Background: Patients (pts) with rheumatoid arthritis (RA) often experience comorbidities that may affect efficacy and safety when treated with different drugs.1 Baricitinib (BARI) is a selective inhibitor of Janus kinase2,3 1 and 2 that improves disease activity in pts with RA with an acceptable safety profile.4-6 Objectives: To investigate the effect of selected comorbidities on safety and efficacy outcomes in pts treated with BARI. Methods: Pts were selected for this post hoc analysis on the basis of historical or ongoing conditions defined by Medical Dictionary for Regulatory Activities and divided by the following comorbidity subgroups: depression, osteoporosis, hepatic disorders, and previous cardiovascular events. Efficacy outcomes included 20% and 50% improvement in American College of Rheumatology 20 Response (ACR20) and American College of Rheumatology 50 Response (ACR50) criteria, respectively; the proportion of pts who achieved a Disease Activity Score for 28- joint count using high-sensitivity C-reactive protein (DAS28-hsCRP) score ≤3.2; and change from baseline in Health Assessment Questionnaire-Disability Index (HAQ-DI) at week 12. Pts who had an inadequate response (IR) to conventional disease-modifying antirheumatic drugs (cDMARDS) from 5 studies with BARI 4 mg and placebo (PBO) were included in efficacy analyses (N=1684) and safety analyses (N=1683). The interaction of comorbidity by treatment was analysed using logistic regression or analysis of variance modelling. Interaction tests were performed within each comorbidity subgroup, and the effect size in pts with and without the comorbidity was analysed. Results: Pts in the efficacy set had similar baseline demographic and diseaseactivity characteristics across treatments within each comorbidity subgroup. The presence of a comorbid condition did not affect the incidence of treatmentemergent adverse events (TEAEs), serious adverse events (AE), discontinuations, or deaths caused by AEs for BARI 4 mg vs PBO (Table 1). The most common TEAEs across the subgroups for BARI and PBO were nasopharyngitis and upper respiratory tract infection. For cDMARD-IR pts, change from baseline for each comorbidity subgroup for ACR20, ACR50, DAS28-hsCRP ≤3.2 response, and HAQ-DI was higher for BARI 4 mg compared with PBO. Within each comorbidity subgroup, BARI responses compared with PBO were similar (interaction P >0.1) (Table 2). Conclusions: Treatment with BARI 4 mg showed similar effect in selected comorbidity subgroups with depression, osteoporosis, cardiovascular events, and hepatic impairment for efficacy and safety. No trends were noted for pts in each comorbidity subgroup for increased risk of events after treatment with BARI 4 mg compared with PBO.