Itching control and long-term remission of atopic dermatitis by TAP1503

Summary: Abstract Body: Atopic dermatitis (AD) is a chronic inflammatory disease often causes intense itching. Inflammatory mediators can directly stimulate itch receptors in the skin or sensitize nerve fibers, leading to heightened itch perception. Additionally, persistence of pathogenic resident memory T cells(TRM) , repeated barrier disruption and heightened immune responsiveness in previously affected areas may contribute to lesion recurrence after therapy is discontinued.Tapinarof has been shown to reduce TRM generation and pruritus in inflammatory skin conditions, potentially by activating the aryl hydrocarbon receptor (AhR) and modulating key inflammatory pathways. Through these mechanisms, it may also help stabilize the skin barrier and dampen local immune responses.Here, we report the results from a randomized, double-blind, parallel group, vehicle-controlled Phase III clinical study(CTR20231413), which conducted in more than 30 sites in China. The study evaluated the efficacy and safety of tapinarof(TAP1503) or vehicle applied twice daily for 8 weeks to 272 adults and children 2 years of age and older with moderate-severe AD. Afterward, 43 participants volunteered for a long-term follow-up of 52 weeks, discontinuing medication once their Investigator’s Global Assessment (IGA) score reached 0, and resuming treatment if their IGA returned to 2. Itching began to improve on Day 1, with a mean PP-NRS change rate of -5.23%. By Day 2, there was a further, more significant improvement (mean PP-NRS change rate: -8.00%; 95% CI, -16.46% to 0.46%), it was also significantly improved compare with the vehicle-controlled group(p=0.032). During the extended follow-up, approximately 70% of participants in the experimental group did not experience any AD flare-ups after discontinuing treatment, up to the 52-week endpoint. In conclusion, this first and only study in China to use tapinarof (TAP1503) for treating AD-associated pruritus and examining its long-term effects demonstrates that it provides rapid relief and may extend the duration of remission. Yan Zhao¹, Jianzhong Zhang¹, Genhui Chen² 1. Peking University People's Hospital, Beijing, Beijing, China. 2. Shanghai Thederma Pharmaceutical Co., Ltd, Shanghai, China. Clinical Research: Interventional Research