By Chris Wack

Aridis Pharmaceuticals shares doubled in premarket trading to 37 cents a share on Wednesday after the company said it received positive feedback from the Food and Drug Administration on its proposed single confirmatory Phase 3 study of investigational monoclonal antibody candidate AR-301.

The clinical-stage antibiotic add-on discovery company said it is developing AR-301 as an adjunctive therapy in combination with standard-of-care antibiotics for the treatment of pneumonia caused by Gram-positive bacteria Staphylococcus aureus in mechanically ventilated hospitalized patients.

Aridis said the FDA agreed on the design of a single confirmatory Phase 3 superiority study required to support the submission of a biologics license application for AR-301.

The FDA also agreed to a proposed expansion of the confirmatory Phase 3 study of S. aureus ventilator-associated pneumonia patients to include ventilated hospital-acquired pneumonia and ventilated community-acquired pneumonia patients.

The Phase 3 study's primary efficacy endpoint would be a clinical cure of pneumonia in adults 65 years old and over, at day 21 post-treatment. Its secondary endpoints would include clinical cure rates of pneumonia in study subjects less than 65 years of age, safety levels including all-cause mortality, and healthcare utilization.

Write to Chris Wack at chris.wack@wsj.com

(END) Dow Jones Newswires

May 31, 2023 09:28 ET (13:28 GMT)