Risk of venous thromboembolism associated with tofacitinib in patients with rheumatoid arthritis: a population-based cohort study

Objective To evaluate the risk of venous thromboembolism (VTE) with tofacitinib compared with TNFis in patients with RA. Methods RA patients initiating tofacitinib or a TNFi without use of any biologic or tofacitinib any time prior were identified from IBM 'MarketScan' (2012-18), Medicare (parts A, B and D, 2012-17) or 'Optum' Clinformatics (2012-19) and followed until treatment discontinuation, treatment switch, insurance disenrollment or administrative censoring. The primary outcome, VTE, was identified using inpatient claims for pulmonary embolism or deep vein thrombosis. A Cox proportional hazards model provided hazard ratio (HR) and 95% CIs after accounting for confounding through propensity score fine-stratification weighting. HRs were pooled across databases with inverse variance meta-analytic method. Results A total of 42 201, 25 078 and 20 374 RA patients were identified from MarketScan, Medicare and Optum, respectively, of whom 7.1, 7.1 and 9.7% were tofacitinib initiators. The crude incidence rates per 100 person-years (95% CI) were 0.42 (0.20-0.77) and 0.35 (0.29-0.42) in MarketScan, 1.18 (0.68-1.92) and 0.83 (0.71-0.97) in Medicare, and 0.19 (0.04-0.57) and 0.34 (0.26-0.44) in Optum for tofacitinib and TNFis, respectively. Propensity score-weighted HRs showed no significant differences in the risk of VTE between tofacitinib and TNFis in any database with a pooled HR (95% CI) of 1.13 (0.77-1.65). Conclusion Overall, VTE occurred infrequently (<1 per 100) in a total of 87 653 RA patients initiating tofacitinib or a TNFi. We observed no evidence for an increased risk of VTE for tofacitinib vs TNFis in RA patients.