Aridis Pharmaceuticals, Inc. announced that patient enrollment is closed in the AR-301 Phase 3 clinical study. The Company is on track to complete database lock, data analyses, and expects to disclose top-line data in December 2022. The AR-301-002 Phase 3 'ASAP-1' study compares the superiority of adjunctive use of the investigational, targeted immunotherapy candidate AR-301 with standard of care (SOC) antibiotics versus SOC antibiotics alone, for the treatment of ventilator associated pneumonia (VAP) caused by Gram-positive bacteria Staphylococcus aureus (S. aureus).

Patients enrolled will complete their treatment and 28-day follow-up per study protocol. Safety and efficacy of the fully human monoclonal antibody AR-301 (20 mg/kg infusion given once) are being evaluated using a randomized, double-blinded, placebo-controlled, superiority clinical trial design. The study was initiated as a globally harmonized Phase 3 study after the design and primary endpoint of clinical cure of pneumonia were reviewed by the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA).

This global study involved 153 clinical sites in 20 countries across U.S., Latin and South Americas, Europe, and Asia. ASAP-1 is the first ever Phase 3 superiority clinical study evaluating immunotherapy with a human monoclonal antibody to treat acute pneumonia. In the study, all patients received SOC antibiotics in combination with either AR-301 immunotherapy or placebo by intravenous infusion following the diagnosis of severe pneumonia and confirmation of S. aureus in the patient's lung fluid, using either the classical microbiology test and/or a rapid diagnostic test.

The primary endpoint of clinical cure of pneumonia is a composite endpoint which comprises three objectively measured outcomes that must be met for declaration of treatment success, namely 1) survival, 2) removal of mechanical ventilation, and 3) resolution of signs and symptoms of pneumonia. The ongoing Phase 3 study remains blinded. The independent Data Safety Monitoring Committee, which has access to unblinded data, has not expressed any safety concerns.

ASAP-1 is the first of two Phase 3 studies required for licensure. AR-301 is a fully human IgG1 monoclonal antibody that specifically targets S. aureus alpha-toxin, an important virulence factor that is secreted by both methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA).