Potential Anti-SARS-CoV-2 Antibody Able to Inhibit In Vitro Virus Infection in Preclinical Studies

Sorrento Therapeutics announced anti-SARS-CoV-2 antibody, STI-1499, demonstrated 100% inhibition of SARS-CoV-2 virus infection in an in vitro virus infection experiment at a very low antibody concentration.

As recently announced, 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.

Sorrento has been screening billions of antibodies in its proprietary G-MAB™ fully human antibody library 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. These blocking antibodies were further tested for their ability to inhibit SARS-CoV-2 virus infection 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, 2020.

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

Sorrento has determined STI-1499 will likely be the first antibody in the antibody cocktail (COVI-SHIELD™) it is developing, as recently announced. 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. Sorrento plans to request priority evaluation and accelerated review from regulators to determine the best pathway to make any potential treatment available as soon as possible. Sorrento's existing state-of-the-art cGMP antibody manufacturing facility in San Diego is expected to be able to produce up to two hundred thousand doses per month and the Company intends to produce a million doses at risk while seeking FDA approval for any STI-1499 product candidate. The Company is seeking potential government support and pharmaceutical partners to further scale up STI-1499 manufacturing capacity with a goal of potentially providing tens of millions of doses in a short period of time to meet the vast projected demand.

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