Monoclonal Antibody Cocktail Retains Effectiveness Against the Omicron Variant

California-based Aridis Pharmaceuticals, Inc. announced today that its fully human monoclonal antibody (mAb) cocktail AR-701 is broadly reactive against the Omicron SARS-CoV-2 variant. 

In vitro neutralization studies using live coronaviruses showed that AR-701 achieved broad, potent neutralization against all SARS-CoV-2 variants tested, and SARS (Severe Acute Respiratory Syndrome), MERS (Middle East Respiratory Syndrome Coronavirus), and seasonal ('common cold') human coronaviruses. 

AR-701 is engineered to be long-acting and is expected to provide relevant drug levels for up to one year from prophylactic or therapeutic treatment.

AR-701 consists of AR-703 and AR-720 mAbs; each neutralizes coronaviruses using distinct mechanisms of action, namely inhibition of viral fusion and entry into human cells (AR-703) and blockage of viral binding to the human 'ACE2' receptor (AR-720).

The two mAbs complement and synergistically enhance each other, creating a potent first-in-class cocktail. AR-703 binds to the 'S2' stalk region of spike proteins from betacoronaviruses and binds to the Omicron variant with no loss in affinity compared to the original Wuhan strain.

"Omicron has rendered current COVID-19 vaccines and monoclonal antibodies substantially less effective, and likely future COVID 19 variants will arise that continue this trend," said Vu Truong, Ph.D., CEO of Aridis Pharmaceuticals, in a press release.

"AR-701 is the result of our successful search for a mAb therapy that is directed against a conserved region of the virus that would be less vulnerable to mutations and new variants such as Omicron."

"To our knowledge AR-701 is the only COVID-19 therapy that targets two distinct viral mechanisms of action, making it much harder for the virus to generate resistance, and exhibits an unmatched combination of broad reactivity and high efficacy," continued Dr. Truong.

Aridis Pharmaceuticals, Inc., located in Los Gatos, CA,  utilizes its proprietary ʎPEXTM and MabIgX® technology platforms to rapidly identify rare, potent antibody-producing B-cells from patients who have successfully overcome infection and to manufacture mAbs rapidly) for treatment of critical infections.