REGEN COV

Subject: Science & tech

Context: Regeneron to seek US approval for COVID-19 cocktail to be used for prevention.

Concept:

REGEN-COV, a combination of casirivimab and imdevimab, protected household contacts from exposure to SARS-CoV-2, with 72 per cent protection against symptomatic infections in the first week, and 93 per cent after that, according to trial data released by the company.
The current trial tested REGEN-COV for use as a passive vaccine, which involves direct delivery of virus-fighting antibodies into the body unlike traditional vaccines in which the receiver’s immune system is activated to develop its own antibodies.
These data using REGEN-COV as a passive vaccine suggest that it may both reduce transmission of the virus as well as reduce viral and disease burden in those who still get infected.

Antibody Cocktail

An antibody is a protein made by immune cells that is just the right shape and size to attach itself to a specific spot on a particular foreign substance, such as a virus or bacteria in the blood.
By attaching, the antibody can potentially directly stop these invaders from causing an infection, or it can mark them for destruction by immune cells.
The REGN-COV2 antibody cocktail in these trials is a combination of two potent, complementary, virus-neutralizing antibodies.
They were selected by Regeneron scientists after screening thousands of options. Each binds to the spike proteins on the virus, which is that corona we see in pictures of the virus.
Those spikes allow the virus to attach to and penetrate other cells. If we block that interaction, the virus is less successful at binding to healthy cells.
One antibody comes from a human survivor of COVID-19.. The other antibody is from a mouse that has been engineered to have a human immune system. The cocktail does not contain human blood products.