Topical tacrolimus nanoemulsion, a promising therapeutic approach for uveitis.

Uveitis is a sight threatening inflammatory disorder that affects all ages and remains a significant cause of visual loss. Inflammatory activity plays an important role in the whole pathogenesis of uveitis. Treatment of uveitis is mainly driven by corticosteroids that have potential side effects. Recent investigations demonstrated that tacrolimus inhibits T-cell proliferation and suppresses release of inflammatory cytokines. Since tacrolimus is a definite immunosuppressive agent, and since inflammatory process has been involved in uveitis, the compound must have effect on the progression of uveitis through reduction in inflammatory activity. Even results of the clinical trials demonstrate that tacrolimus have useful role in treatment of sight threatening uveitis that is refractory to other therapy. Studies also indicate that long term use of tacrolimus is well tolerated. However, its use in uveitis is limited because of its poor physico-chemical properties including poor aqueous solubility and high molecular weight (822 Da). Therefore, we have proposed that tacrolimus nanoemulsion administered topically is a promising therapeutic approach to treat uveitis. Based on previous evidences, we have hypothesized that nanoemulsion formulation of tacrolimus can improve efficacy and safety profile of tacrolimus.