Antibody found to block COVID-19 virus 100% in experiments 

US-based Sorrento Therapeutics has announced that an antibody has demonstrated its ability to completely block SARS-CoV-2 infection of healthy cells in preclinical laboratory experiments.

SARS-CoV-2 is the virus responsible for the COVID-19 pandemic.

The results on Friday showed that Sorrento's anti-SARS-CoV-2 antibody, STI-1499, completely neutralised the virus infectivity at a very low antibody dose, making it a prime candidate for further testing and development.

Initial biochemical and biophysical analyses also indicate STI-1499 is a potentially strong antibody drug candidate, said the antibody-centric biopharmaceutical company headquartered in San Diego, California.

"Our STI-1499 antibody shows exceptional therapeutic potential and could potentially save lives following receipt of necessary regulatory approvals," Henry Ji, Chairman and CEO of Sorrento, said in a statement.

"We at Sorrento are working day and night to complete the steps necessary to get this product candidate approved and available to the waiting public."

Sorrento aims to generate an antibody cocktail product that would act as a "protective shield" against SARS-CoV-2 coronavirus infection and remain effective even if virus mutations render a single antibody therapy less effective over time.

The company has been screening billions of antibodies and has so far identified hundreds of antibody candidates that bind the S1 subunit of the SARS-CoV-2 Spike protein.

Approximately one dozen of these antibodies have demonstrated the ability to block the S1 protein's interaction with human angiotensin-converting enzyme 2 (ACE2), the receptor used for viral entrance into human cells, Sorrento said.

These blocking antibodies were further tested in an in vitro SARS-CoV-2 virus infection model pursuant to a preclinical testing agreement for COVID-19 therapeutic candidates that was previously announced on March 31.

Among the antibodies showing neutralizing activity, the antibody, STI-1499, stood out for its ability to completely block SARS-CoV-2 infection of healthy cells in the experiments.

Sorrento said STI-1499 will likely be the first antibody in the antibody cocktail (COVI-SHIELD) it is developing.

STI-1499 is also expected to be developed as a stand-alone therapy, (COVI-GUARD) because of the high potency it has exhibited in experiments to date.