Aclaris Therapeutics Initiates Phase 1a/1b Program for its Novel Bispecific Antibody ATI-052

Core Insights - Aclaris Therapeutics has initiated a Phase 1a/1b clinical program for ATI-052, a bispecific antibody targeting TSLP and IL-4R, which is expected to be a best-in-class treatment for immuno-inflammatory diseases [1][2] Group 1: Clinical Development - The Phase 1a program will include single and multiple ascending dose (SAD/MAD) studies in healthy volunteers, followed by a Phase 1b proof of concept assessment in up to two undisclosed indications [2] - Completion of the Phase 1a SAD/MAD portion is anticipated by the end of 2025, with top line results expected in early 2026, and Phase 1b results in the second half of 2026 [2] Group 2: Mechanism of Action - ATI-052 is designed to exhibit high binding affinity and dual blockade of TSLP and IL-4R, inhibiting key proinflammatory pathways involved in Th2-mediated inflammation and allergic diseases [2][4] - The bispecific antibody's dual binding capability may enhance efficacy compared to traditional monoclonal antibodies, with potential applications for various immune-modulated diseases [3] Group 3: Product Profile - ATI-052 targets TSLP at the top of the inflammatory cascade and blocks downstream IL-4 and IL-13, which are critical cytokines in Th2-mediated inflammation [4] - The antibody utilizes the same TSLP antigen-binding fragment as bosakitug (ATI-045) but is engineered for tighter binding to the neonatal Fc receptor (FcRn), potentially extending its half-life [4] Group 4: Company Overview - Aclaris Therapeutics is a clinical-stage biopharmaceutical company focused on developing novel product candidates for immuno-inflammatory diseases, with a robust R&D pipeline [5]