FOSTER CITY, Calif. — October 9, 2026
Sagimet Biosciences Inc. announced positive full 52-week results from the Phase 3 ASC40-304 open-label extension trial of denifanstat in patients with moderate-to-severe acne vulgaris. The findings, generated by licensing partner Ascletis BioScience in China, will be presented alongside mechanistic data at the 2026 Fall Clinical Dermatology Conference in Las Vegas. Denifanstat demonstrated continued improvement across efficacy endpoints, including 57% Investigator’s Global Assessment (IGA) success, a 72% reduction in total lesions, and a 77% reduction in inflammatory lesions. The treatment was generally well tolerated throughout the study.
FASN Inhibition Targets Key Acne Mechanisms
Denifanstat is an investigational, once-daily oral small-molecule inhibitor of fatty acid synthase (FASN), an enzyme involved in lipid production. By inhibiting FASN, the therapy is designed to reduce de novo lipogenesis, sebum production and inflammation, addressing important biological mechanisms involved in acne development. Clinical and preclinical findings presented by Sagimet and Ascletis support further investigation of FASN inhibition as a potential oral treatment approach for moderate-to-severe acne. The reported findings do not establish regulatory approval or confirm long-term comparative efficacy because the extension study was open-label.
Phase 3 Extension Builds on Earlier Clinical Findings
The ASC40-304 extension enrolled 240 patients who had previously participated in the 12-week randomized, double-blind, placebo-controlled Phase 3 ASC40-303 trial. Participants received denifanstat 50 mg once daily for up to 40 additional weeks, allowing those originally assigned to denifanstat to receive up to 52 weeks of treatment. The extension primarily evaluated long-term safety, with efficacy measures including IGA success and changes in total and inflammatory lesion counts. According to the company, improvements across efficacy endpoints continued beyond the results observed at week 12, and denifanstat was generally well tolerated.
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U.S. AURORA Phase 3 Trial Advances Toward Enrollment
Sagimet is advancing denifanstat outside China, while Ascletis holds the exclusive license for its development in China. The AURORA Phase 3 trial is preparing to evaluate denifanstat in approximately 800 U.S. patients aged 12 years and older with moderate-to-severe acne, including an anticipated 450 adolescents. Participants will be randomized in a 2:1 ratio to receive denifanstat 50 mg or placebo once daily for 12 weeks. The study will assess treatment success using a global assessment score and changes in inflammatory and non-inflammatory lesion counts. Sagimet reported that trial sites have been activated, institutional review board approvals are in place, and patient screening has begun.
Source::Sagimet Biosciences press release
