Real-world Comparative Risks of Herpes Virus Infections in Tofacitinib and Biologic-treated Patients with Rheumatoid Arthritis

Ann Rheum Dis. 2016 Apr 25;0:1–5 doi: 10.1136/annrheumdis-2016-209131

Herpes Zoster (HZ) complications can cause considerable morbidity including debilitating pain syndromes. Clinical trials of tofacitinib have suggested it may increase the risk of HZ. Although unclear, the mechanism may involve reduced CD4 T-cell function and interference of interferon signalling. Following approval of tofacitinib in the US in 2012, real-world data from Medicare (2006–2013) and from the US longitudinal database, Marketscan, (2010–2014) were analysed. A total of 2526 patients who had no previous history of HZ and who started taking tofacitinb were compared with patients initiating biologics (n=67,200). Abataceptwas included as referent because it is commonly used as a second- or subsequent-line therapy in RA. The primary outcome was the first HZ event. The composite outcome of HZ or herpes simplex virus (HSV) was also evaluated.After controlling for confounding factors including age, sex, and baseline factors including MTX use and glucocorticoid dose, risk for HZ was 2.01 (% CI 1.40–2.88) compared with abatacept. No biologics were significantly different compared to abatacept. After multivariable adjustment, composite HZ and HSV rates were also significantly different for tofacitinib compared with abatacept (HR=1.40, 95% CI 1.09–1.81). To check for surveillance bias, a sensitivity analysis included patients who received antiviral therapy, and this showed similar results.This first, real-life safety evaluation of the incidence of HZ in patients with RA is consistent with the clinical trial data but the importance of the findings should be considered in context with the overall risk profile of the therapy, as well as patient vaccination.