INCREASED THROMBOEMBOLIC RISK OF JAK INHIBITORS AFTER SWITCHING FROM BIOLOGIC DMARDS IN PATIENTS WITH RHEUMATOID ARTHRITIS

BackgroundSafety concerns regarding JAK inhibitors have grown since the ORAL surveillance trial reported that their use was associated with an increase in major adverse cardiovascular events compared to TNF inhibitors. However, real-world data on the association between JAKi and thromboembolic events are sparse.ObjectivesWe compared the incidence of thromboembolic events (TEs) before and after switching to Janus kinase inhibitors (JAKi) from biologic disease-modifying anti-rheumatic drugs (bDMARDs) in patients with rheumatoid arthritis (RA).MethodsAmong patients with a diagnostic code for RA taking bDMARDs, patients who switched to JAKi or another bDMARD between March 2015 and December 2020 were included in this self-controlled case series study. The outcome was the occurrence of TEs. The incidence rate ratios (IRRs) for TEs in the period after switching to JAKi or another bDMARD compared with the period before switching were calculated based on an assumed Poisson distribution.ResultsThere were 1,150 and 2,254 patients who switched to JAKi and another bDMARD, respectively. The mean follow-up duration was 4.5 ± 1.8 years. In the JAKi group, the IRR for TE after drug switching was 1.56 (95% confidence interval [CI] 1.22–1.98, P < 0.001) compared with the period before the drug switch; in the bDMARD group, the IRR was 1.16 (95% CI 0.98–1.38, P = 0.079).ConclusionSwitching from bDMARDs to JAKi was associated with an increase in TE incidence in RA patients in a real-world setting.Disclosure of InterestsNone declared