Aridis Pharmaceuticals, Inc. announced the closing of patient enrollment in the multiple ascending dose (MAD) and dose-ranging cohorts in the Phase 2a clinical trial of AR-501 in cystic fibrosis (CF) patients. The Company is on track to complete database lock, data analyses, and disclose top-line data in the first quarter of 2023. The Phase 2a study enrolled 39 CF patients from 24 clinical centers in the US.

The CF patients were randomized and treated in 4 cohorts; 3 cohorts received three weekly multiple ascending doses of active drug at 6.4 mg, 20 mg and 40 mg or placebo, while the 4th Cohort being dose-ranging with subjects randomized to three weekly doses of AR-501 6.4 mg, 20 mg, or 40 mg, or placebo. CF subjects were followed for 28 days after last study dose for safety and pharmacokinetics (PK) of inhaled AR-501. Aridis previously reported positive Phase 1 safety data in June 2020 in healthy adults who were exposed to either a single ascending dose (SAD) regimen or a multiple ascending dose (MAD) regimen.

AR-501 is being developed in collaboration with the Cystic Fibrosis Foundation (CFF) and has been granted Orphan Drug Designation (ODD), Fast Track, and Qualified Infectious Disease Product (QIDP) designations by the US Food and Drug Administration (FDA). In addition, the European Medicines Agency (EMA) granted ODD to AR-501.