Continued JAK inhibitor treatment on the risk of recurrent herpes zoster reactivation in patients with immune-mediated inflammatory diseases: A nationwide population-based study in South Korea

Abstract

BackgroundTo investigate the risk of recurrent herpes zoster (HZ) reactivation under continued Janus kinase inhibitor (JAKi) therapy in patients with immune-mediated inflammatory diseases (IMID) who developed HZ reactivation. MethodsData from the Korean Health Insurance Review and Assessment Service (HIRA) of patients with rheumatoid arthritis (RA) or ulcerative colitis (UC) gathered from 2007 to 2021 were analyzed. ResultsA total of 3947 (RA 3540, UC 407) receiving JAKi were included. After median 0.95 years (IQR, 0.93–2.58) of therapy, 611 (15.5%) patients developed HZ reactivation (incidence rate: 8.38/100 person-years [PY]). After excluding 151 patients with lack of data after HZ reactivation, 460 patients (JAKi continuation group, n = 386 [83.9%]; JAKi discontinuation group, n = 74 [16.1%]) were analyzed for the risk of subsequent recurrent HZ reactivation. During further follow-up of median 1.11 years (IQR, 0.53–1.91), 36 (9.3%) and 6 (8.1%) patients in the JAKi continuation group and JAKi discontinuation group experienced a recurrence of HZ, respectively. The incidence rate of subsequent recurrent HZ reactivation was not significantly different between the two groups (5.3/100 vs. 5.9/100 PY; P = 0.52). After adjusting for age, sex, usage of corticosteroids, and antiviral agents, continued use of JAKi was not a significant risk factor for subsequent HZ reactivation (adjusted hazard ratio, 0.71 [CI, 0.29–1.72], P = 0.45). ConclusionIn this nationwide population-based study on patients with RA or UC, continued use of JAKi was not associated with a significant risk of subsequent recurrent HZ reactivation. JAKi therapy may be maintained in patients with IMID even after HZ reactivation.