LAUSR

A method is reported using ionic liquids for topical delivery of siRNA into skin for the treatment of psoriasis. Systemic antibodies targeting tumor necrosis factor–α (TNF-α) and interleukin-17A (IL-17A) are effective in plaque psoriasis. Despite their popularity, safety concerns pose a challenge for systemic biologics. While anti–TNF-α and anti–IL-17A antibodies effectively inhibit respective proteins, we hypothesize that an approach based on local silencing of an upstream target such as NFKBIZ can be advantageous for treating psoriasis. However, effective delivery of small interfering RNA (siRNA) into the skin is a substantial hurdle due to skin’s barrier function and poor stability of siRNA. Using ionic liquids as an enabling technology, we report on the effective delivery of NFKBIZ siRNA into the skin and its therapeutic efficacy in a psoriasis model. Treatment with IL-siRNA suppressed aberrant gene expression and resulted in down-regulation of psoriasis-related signals including TNF-α and IL-17A. These results provide a framework for a topical delivery platform for siRNA.