Ascletis Pharma Inc. has announced positive topline results from a randomized, double-blind, placebo-controlled Phase I clinical trial in the United States evaluating ASC50, a potential best-in-class oral small molecule IL-17 inhibitor. The study assessed the safety, tolerability, pharmacokinetics, and IL-17A target engagement profile of ASC50 in healthy participants who received single ascending doses ranging from 10 mg to 600 mg or placebo. The company stated that the elimination half-life of ASC50 ranged from 43 to 104 hours depending on the dose. Results from this study were announced on December 15, 2025. Ascletis will host a conference call to discuss the findings. The company noted that there is no guarantee of successful development, manufacturing, or commercialization of ASC50.