SARS-CoV-2 Monoclonal Antibody Treatment

SARS-CoV-2 Monoclonal Antibody Treatment Description

The main target of SARS-CoV-2 neutralizing monoclonal antibodies is the surface spike glycoprotein that mediates viral entry into host cells. Essentially all monoclonal antibodies of interest target this protein.

These agents are often created by identifying pathogen-specific B cells of patients who have recently recovered from COVID-19 or by immunizing mice genetically modified to have a humanized immune system and harvesting effective antibodies from them.

Monoclonal antibodies have singular activity against a predetermined target; they, therefore, differ from convalescent plasma, which consists of polyclonal antibodies in serum derived from patients who are convalescing from an infection.

SARS-CoV-2 Monoclonal Antibodies - U.S. FDA Emergency Use Authorized

The FDA has currently authorized three anti-SARS-CoV-2 monoclonal antibody products. These products are authorized to treat non-hospitalized patients with mild to moderate COVID-19.

The three products that have been FDA authorized are:

Regeneron's (NASDAQ: REGN) REGEN-COV2 (Casirivimab and Imdevimab) is potent, virus-neutralizing antibodies that form the REGEN-COV Antibody Cocktail bind non-competitively to the critical receptor binding domain of the virus's spike protein, which diminishes the ability of mutant viruses to escape treatment and protects against spike variants that have arisen in the human population, as detailed in Science, published on August 21, 2020.

Eli Lilly's (NYSE: LLY) Bamlanivimab (LY-CoV555) neutralizing IgG1 monoclonal antibody (mAb) is directed against the spike protein SARS-CoV-2 coronavirus. Bamlanivimab was designed to block viral attachment and entry into human cells, thus neutralizing the virus, potentially preventing and treating COVID-19. In addition, a second Lilly antibody, LY-CoV016, which binds a different epitope in the SARS-CoV-2 spike region, has been added to the BLAZE-1 clinical trial. Etesevimab (LY-CoV016, also known as JS016) is a recombinant fully human monoclonal neutralizing antibody, which specifically binds to the SARS-CoV-2 surface spike protein receptor-binding domain with high affinity and can block the binding of the virus to the ACE2 host cell surface receptor.

Vir Biotechnology, Inc.'s Sotrovimab (VIR-7831, GSK4182136) (Xevudy®) is a fully human anti-SARS-CoV-2 monoclonal antibody selected based on its potential to neutralize the virus in vitro, kill infected cells, provide a high barrier to resistance, and achieve high concentrations in the lungs. Vir Biotechnology's (NASDAQ: VIR) antibody binds to an epitope on SARS-CoV-2 shared with SARS-CoV-1. The data that support the EUA for sotrovimab come from the Phase 3 COMET-ICE trial, which included outpatients with mild to moderate COVID-19 who were at high risk for progression to severe disease and/or hospitalization.

SARS-CoV-2 Monoclonal Antibodies - Experimental

Brii Biosciences Limited - BRII-196/BRII-198 are non-competing SARS-CoV-2 monoclonal neutralizing antibodies derived from convalesced COVID-19 patients. They have been specifically engineered to reduce the risk of antibody-dependent enhancement and prolong the plasma half-lives for potentially more durable treatment effect. In addition, their non-overlapping epitope binding regions provide a high degree of neutralization activity against SARS-CoV-2. Authorizations are pending in the USA and China.

AstraZeneca - Positive high-level results from the PROVENT Phase III pre-exposure prophylaxis trial showed AstraZeneca's COVID-19 Antibody AZD7442 achieved a statistically significant reduction in the incidence of symptomatic COVID-19, the trial's primary endpoint.

SARS-CoV-2 Monoclonal Antibodies News

August 26, 2021 - UK medicines regulator has approved Ronapreve (REGEN-COV) for COVID-19 treatment. Ronapreve is administered as an infusion or multiple injections. This product is already licensed for emergency use in more than 20 countries – including the US, Japan, and India.

August 25, 2021 - Brii Biosciences (HKG: 2137) announced positive results from the NIAID-sponsored Activ-2 trial in outpatients. “We are thrilled to announce the interim Phase 3 results from ACTIV-2, which demonstrate a significant reduction in the endpoint of hospitalizations or death among non-hospitalized people with mild COVID-19 who were treated with BRII-196/BRII-198,” said Teresa H. Evering, M.D., M.S., Weill Cornell Medicine, co-lead investigator of BRII-196/BRII-198 in ACTIV-2.