The Effect of Tumor Necrosis Factor-Alpha Inhibitors on Uveitis in Patients with Ankylosing Spondylitis

BACKGROUND: Tumor necrosis factor-alpha (TNF-α) inhibitors (TNFis), which are the main treatment for ankylosing spondylitis (AS), have been reported not only to reduce the incidence of anterior uveitis (AU) but also to induce it, and these effects differ among the various types of TNFis in clinical use. The present study investigated the effect of TNFis on uveitis by analyzing the long-term clinical course of AU in AS patients treated with TNFi therapy. METHODS: Patients treated with at least one TNFi between January 2007 and July 2017 were reviewed, and 54 patients with at least one episode of AU were included in this study. The TNFis included anti-TNF-α antibodies (adalimumab, infliximab, and golimumab), and a soluble TNF receptor molecule (etanercept). The effect of prevention of AU, the likelihood of new-onset uveitis after the initiation of TNFi therapy, and the effects of drug switching and dose escalation were assessed. RESULTS: The first uveitis flare was observed before TNFi therapy in 39 patients and after TNFi therapy in 15 patients. Anti-TNF-α antibodies were more efficacious in decreasing the recurrence of AU than etanercept. Among patients in which uveitis first occurred after beginning TNFi therapy, patients on etanercept tended to first develop AU less than 1 year after starting the drug, and their AS tended to be well-controlled at the time of uveitis flares. Patients with a uveitis flare before their medication was switched did not recur afterwards, and five of eight patients showed no relapse after dose escalation. CONCLUSION: TNFis have various effects on AU. TNFis, particularly anti-TNF-α antibodies, should be considered in patients with AS and frequent AU relapse. Additionally, clinicians should consider whether AU is due to an absence of a therapeutic response of AS to TNFi treatment or to TNFi treatment itself, and appropriate treatment changes should be made accordingly.