Real-world comparative risks of herpes virus infections in tofacitinib and biologic-treated patients with rheumatoid arthritis.

Objective To evaluate the risks of herpes zoster (HZ) and herpes simplex virus (HSV) infection associated with tofacitinib compared with biologic agents among patients with rheumatoid arthritis (RA).Methods Using health plan data from 2010 to 2014, patients with RA initiating tofacitinib or biologics with no history of HZ or HSV were identified, as were incident cases of HZ or HSV. Crude incidence rates were calculated by drug exposure. Cox proportional hazards models evaluated the adjusted association between tofacitinib and HZ, and a composite outcome of HZ or HSV