Aridis Reports Positive Preclinical Efficacy Data for Inhaled Treatment for COVID-19

Aridis Pharmaceuticals announced the development of a highly neutralizing monoclonal antibody AR-711, discovered from convalescent COVID-19 patients that successfully eliminated all detectable SARS-CoV-2 virus in infected animals at substantially lower doses than parenterally administered (injected) COVID-19 monoclonal antibodies (mAb). The potency of AR-711 and its direct delivery to the lungs by inhaled administration may facilitate broader treatment coverage and dose sparing not achievable by parenteral administration.

AR-711 is directed against the conserved receptor-binding domain (RBD) region of the original SARS-CoV2 virus and its newly emerging variants including the currently prevalent strain G614.

AR-711 is engineered to be long-acting in blood for up to six to 12 months.

In the animal challenge study, golden Syrian hamsters were pre-infected with SARS-CoV-2 before a single inhalation exposure of AR-711 liquid aerosols. AR-711 eliminated detectable SARS-CoV-2 virus at all dose levels tested, with the lowest lung deposited dose of 0.03 mg/kg.

AR-711 is stabilized using a proprietary formulation designed to protect the mAb from the physical stresses imparted by commercial nebulizer delivery devices on protein drugs.

An inhalable treatment that can be self-administered using a wide variety of commercially available nebulizers can facilitate broader coverage in non-hospitalized settings and at a scale not achievable using conventional inpatient IV infusion treatments.

"As we expected, combining a highly potent monoclonal antibody with direct delivery to the lungs, which is the main target of the COVID-19 virus, achieved impressive efficacy in these animal models. The therapeutic dose that we observed corresponds to an estimated adult human equivalent efficacious inhaled dose of 2 to 6 milligrams (mg) per dose. This compares very favorably to other clinical stage COVID-19 mAbs, where up to 8,000 mg are being studied to achieve clinical benefit," said Hasan Jafri, M.D., Chief Medical Offer of Aridis.

"Over 90% COVID-19 symptomatic patients are home bound, under quarantine, and often not treated. While these patients wait, their health can deteriorate, and they could infect those around them. Having a convenient way to self-medicate with the simplicity of an asthma inhaler where the drug is delivered directly to the infection site can have a transformative impact on patients' lives, expand treatment coverage, and ultimately reduce global transmissibility," said Vu Truong, Ph.D., Chief Executive Officer of Aridis Pharmaceuticals.

AR-711 is a fully human immunoglobulin 1, or IgG1, monoclonal antibody discovered from screening the antibody secreting B-cells of convalescent COVID-19 patients. AR-711 exhibits high affinity for SARS-CoV-2 spike protein, approximately 10-fold or higher than mAb candidates currently in late stage clinical testing. AR-711 was previously shown to be effective in prophylactic as well as therapeutic treatment modes in a SARS-CoV-2 viral challenge study. AR-711 was discovered at the University of Alabama at Birmingham and Texas Biomedical Research Institute (originally known as mAb '1212C2'), recently licensed and is currently being developed by Aridis as an inhaled, self-administered treatment for non-hospitalized patients suffering from mild to moderate COVID-19. AR-711 is also one the two mAbs in the company's AR-701 mAb cocktail, which is a separate program being developed as an intravenous treatment of moderate to severe, hospitalized COVID-19 patients.