Biologic therapies and small molecules for the management of non-infectious scleritis: a narrative review

Scleritis refers to a wide spectrum of ocular conditions ranging from mild to sight-threatening scleral inflammation that may compromise visual function and threaten the anatomical integrity of the ocular globe. Most aggressive forms like necrotizing or posterior scleritis are often difficult-to-treat cases, refractory to conventional treatment. The association with systemic diseases, namely rheumatoid arthritis, Sjögren syndrome, granulomatosis with polyangiitis, and relapsing polychondritis, may have prognostic implications as well. A better understanding of the pathogenesis of ocular inflammatory diseases have paved the way to more effective and targeted treatment approaches. In this regard, a growing body of evidence supports the potential role of biologic agents in the management of non-infectious scleral inflammation, either idiopathic or in a background of immune-mediated systemic disorders. Biologic agents such as anti-tumor necrosis factor agents, interleukin-1 and interleukin-6 inhibitors as well as CD20 blockade have displayed promising results. More specifically, several studies have reported their ability to control scleral inflammation, reduce the overall scleritis relapses, and allow a glucocorticoid-sparing effect while being generally well tolerated. Anecdotal reports have also been described with other biologic agents including abatacept, ustekinumab, daclizumab, and alemtuzumab as well as targeted small molecules such as tofacitinib. Further studies are warranted to fully elucidate the role of biologic agents in non-infectious scleritis and investigate specific areas with the aim to administer treatments in the context of personalized medicine. This review summarizes the available data regarding clinical trials, small pilot studies, and real-life experience of the last two decades reporting the use of biologic agents in the management of non-infectious scleritis.