LAUSR

Background Tofacitinib is an oral Janus kinase (JAK) inhibitor. Immunomodulatory therapies can increase the risk for herpes zoster (HZ) in patients with psoriasis. Objective To evaluate the relationship between tofacitinib use and HZ risk. Methods We used phases 2 and 3 and long‐term extension (LTE) data from the tofacitinib development program in psoriasis to calculate HZ incidence rates (IR; events per 100 patient‐years); potential HZ risk factors were evaluated using Cox‐proportional hazard models. Results One hundred thirty (3.6%) patients on tofacitinib (IR 2.55), no patients on placebo, and 2 using etanercept (IR 2.68) developed HZ. Nine patients (7%) were hospitalized, and 8 (6%) had multidermatomal HZ; no encephalitis, visceral involvement, or deaths occurred. In total, 121 (93%) patients on tofacitinib continued or resumed use after HZ. HZ risk factors included Asian descent (hazard ratio [HR] 2.92), using tofacitinib 10 mg twice daily (vs 5 mg twice daily; HR 1.72), prior use of biologics (HR 1.72), and older age (HR 1.30). Limitations Generalizability to other psoriasis populations might be limited. The effect of HZ vaccination was not studied. Conclusion Tofacitinib is associated with increased HZ risk relative to placebo. Asian race, increasing age, higher dose, and prior biologic exposure are associated with heightened risk.