Safety of baricitinib in East Asian patients with moderate-to-severe active rheumatoid arthritis: An integrated analysis from clinical trials

Aim We evaluated the safety of baricitinib in an East Asian (EA) patient population with moderate-to-severely active rheumatoid arthritis (RA), through an integrated sub-analysis of data from the overall baricitinib RA clinical program. Methods Data from EA patients who received any dose of baricitinib from five completed studies (1 Phase 2, 4 Phase 3) and an ongoing long-term extension study were pooled up to 1 September, 2016. Exposure-adjusted incidence rates (EAIR) and incidence rates (IRs), both per 100 patient-years (PY), were calculated. Results This analysis included 740 EA patients with 1294 PY of total baricitinib exposure (maximum 3.5 years). Overall, 109 patients discontinued baricitinib due to adverse events (AEs); EAIR: 8.4. No deaths were reported in this cohort. Serious AEs were reported by 125 patients (EAIR: 9.7). Serious infections were the most common serious AEs (n = 53, IR: 4.15). IR of herpes zoster infection was 6.2; the majority of events were of mild-to-moderate severity. Three cases (IR: 0.23) of tuberculosis were reported. The IRs of malignancy (excluding non-melanoma skin cancer) was 0.99 and EAIR specifically of lymphoma was 0.1. The IR of major adverse cardiovascular events was 0.26, and deep vein thrombosis was reported in four patients (EAIR: 0.3). Two cases of gastrointestinal perforations (EAIR: 0.2) were reported. Conclusion Integrated data show that baricitinib is well-tolerated in EA patients with moderate-to-severely active RA in the context of demonstrated efficacy, which is generally consistent with safety results of the overall study population.