Janus Kinase Inhibitors: Next-Generation Treatment for Uveitis

A large proportion of patients with visual impairment secondary to non-infectious uveitis may require DMARDs. Although these are highly effective, some patients may require alternatives to the currently available immunomodulators due to an inadequate response or undesirable side effects. Janus Kinase Inhibitors (JAKi) are already approved for several autoimmune diseases in rheumatology, gastroenterology and dermatology. To date, JAKi have been studied in phase 3 trials in various types of uveitis. Mechanism of Action: JAKi work by inhibiting the phosphorylation of Janus kinases, which are transmembrane proteins. This blocks the activation of transcription factors, which in turn downregulates cytokine expression and inflammatory mediators. JAKi represent an extremely effective novel therapeutic approach in rheumatology, gastroenterology and dermatology. They have already been approved for the treatment of rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, ulcerative colitis and atopic eczema. In earlier comparative studies with conventional biologics, a better therapeutic response was reported in some cases. Several published case reports report reduced cortisone levels in patients with uveitis who had responded poorly to conventional and biological DMARDs. Approval studies are under way for JIA-associated and ANA-positive anterior uveitis. In summary, JAKi represent an innovative treatment option for patients with non-infectious uveitis in whom DMARDs are contraindicated or ineffective.