The Use of Biologic Therapies in Uveitis

Therapy for autoimmune ophthalmic disease is currently evolving. The improved understanding of the abnormal immune response in the various forms of uveitis has resulted in targeted therapy. The aberrations of the immune system have been characterized by atypical cell populations, cytokine expression, and cell-cell interactions. Different patterns of cytokine expression have now been delineated in the abnormal uveal tract with exaggerated and/or abnormal expression of TNF, IL-1, IL-2, IL-6, and IL-17. The development of therapies for other conditions in which these cytokines play an important role has resulted in the availability of biological agents that have been adopted for use in the therapy for uveitis. Adalimumab and infliximab have been the best studied anti-TNF agents and indeed have now been recommended by an expert panel as first-line treatment of ocular manifestations of Behçet's disease and second-line treatment for other forms of uveitis (Levy-Clarke et al. (Ophthalmology, 2013). Other anti-TNF agents have been studied as well. Daclizumab, a monoclonal antibody directed against the IL-2 receptor, has also demonstrated utility in treating uveitis as have some of the anti-IL1 agents. Gevokizumab has been granted orphan drug designation for the treatment of resistant forms of uveitis. Therapies affecting IL-6, including tocilizumab are being studied, and available medications that block antigen presenting cell and T cell interaction such as abatacept have been reported to be effective in uveitis. Interferons as well as rituximab have also been evaluated in small studies. Although these biologic therapies have provided a larger armamentarium to treat uveitis, challenges remain. Uveitis is not a single illness; rather, it is a manifestation of many potential systemic diseases that may have very specific individual therapeutic targets. Identifying and characterizing these underlying diseases is not always achieved, and more importantly, the most effective therapies for each entity have not been defined.