New Non-Steroidal Topical Therapies for Inflammatory Dermatoses-Part 1: Ruxolitinib

For the twenty-year period from 2001 to 2021, only one new topical molecular entity for an inflammatory skin disease was approved in the United States. This situation has shifted dramatically, with three non-steroidal new molecular entities, each with completely different mechanisms of action, receiving FDA approval in the past year. As a three-part series, each non-steroidal molecule will be reviewed. We focus first on topical ruxolitinib, which received FDA approval in September of 2021 as the first Janus Kinase Inhibitor (JAK) for the treatment of atopic dermatitis. Other topical therapies covered in this review series include tapinarof, an aryl hydrocarbon receptor modulating agent, which was approved for the treatment of psoriasis in May 2022 and topical roflumilast, a highly potent phosphodiesterase-4 inhibitor, which was recently approved in July 2022 for treatment of plaque psoriasis. In addition to their unique mechanisms of action and spectra of activity, each of these agents have unique clinical characteristics - including degree of efficacy, rapidity of onset of efficacy, potential remittive effects, and safety and tolerability profiles. In this review series, we review and summarize the data surrounding each agent, providing a comprehensive overview which will allow dermatology providers to confidently and appropriately integrate them into treatment paradigms. As stated, this contribution focuses on topical ruxolitinib, the only topical JAK therapy FDA approved for treatment atopic dermatitis, and most recently, the first ever approved therapy for nonsegmental vitiligo.