An antibody first identified in a survivor of severe acute respiratory syndrome (SARS) can stop the new coronavirus in its tracks.
The antibody, called S309, targets the ‘spike proteins’ that are on the outside of the virus and are used to invade our cells.
Laboratory tests showed that S309 sticks to the proteins and effectively neutralizes them, say researchers at the University of Washington School of Medicine in Seattle.
It comes on as scientists a California biotech company claims to have found an antibody that completely blocks the virus.
With just a few treatments – and only allowed for emergencies – for the potentially deadly disease, the two new developments offer hope for a therapy or even a vaccine.
Scientists discovered an antibody that inhibits the family of coronaviruses, including the new virus (photo) and SARS, in the blood sample of a SARS survivor
The antibody, called S309, turns off the ‘spike proteins’ that the coronavirus uses to infect human cells. Pictured: Tel Aviv University researchers are studying the new coronavirus
The antibody is now in an accelerated development and testing trajectory at Vir Biotechnology, located in San Francisco.
If successful, it paves the way for the use of S309 – alone or in a cocktail – as a vaccine for at-risk groups or a drug to combat serious life-threatening symptoms
“We still have to demonstrate that this antibody is protective in living systems, which has not yet happened,” said Dr. David Veesler, assistant professor of biochemistry at the University of Washington School of Medicine, in a press release.
“At this time, there are no approved devices or approved therapies that have been proven to fight the coronavirus that causes COVID-19,” he added.
What makes this new antibody different is that it was discovered in 2003 – 17 years ago in someone infected with another coronavirus, SARS.
“This allowed us to move so fast compared to other groups,” said Veesler.
For the study, published in the journal Nature, the team identified several interesting antibodies from a blood sample of the SARS survivor in ‘memory B cells’ that form after an infectious disease.
They usually remember a pathogen that the body removed in the past, sometimes for a lifetime.
This causes the launch of a defense against antibodies to a re-infection.
Experiments found that S309 was particularly effective at targeting and knocking out the spike proteins.
It was able to destroy the virus known as SARS CoV-2 by contacting some of the peak protein near the host cell attachment site.
Tests have shown that the antibody recognizes a binding site seen in many coronaviruses – not just SARS and COVID-19.
The combination of S309 with other weaker antibodies found in the SARS patient increased destruction of the coronavirus.
This multiple cocktail can prevent the virus from mutating into a strain whose single ingredient is defenseless to stop.
It comes on the heels of San Diego-based Sorrento Therapeutics claimed that his antibody, called STI-1499, prevented the virus from entering 100 percent of healthy human cells in petri dishes.
In a press release, the company says it is capable of producing up to 200,000 doses of the antibody per month.
The company has filed for U.S. Food and Drug Administration approval and is currently waiting.