AC Immune SA shares were down 4.26% at $2.47 at the time of publication Thursday after the clinical-stage biopharmaceutical company reported favorable interim Phase 1 results for ACI-19764, an oral small-molecule inhibitor of the NLRP3 inflammasome. The European study found the drug safe and well tolerated across single and multiple ascending dose groups in healthy volunteers, with doses tested up to 20mg daily, a serum half-life exceeding 30 hours, no serious adverse events and no treatment withdrawals. Cerebrospinal fluid exposure provided evidence of brain penetration, while daily doses of 10mg or less reached concentrations above the IC90, the level associated with 90% inhibition. Blinded whole-blood assays also showed dose-dependent inhibition of IL-1beta release. The program has advanced to a Phase 1b cohort involving patients at cardiovascular disease risk, including participants with elevated high-sensitivity C-reactive protein levels and either obesity or type 2 diabetes. Recruitment is active, with initial results expected before year end and further clinical updates anticipated in the first half of 2027. ACI-19764 is intended to reduce pro-inflammatory signaling and chronic inflammation linked to inflammatory, metabolic and neurological diseases.