You've no doubt heard a lot about the COVID-19 vaccines from Pfizer (NYSE:PFE) and Moderna (NASDAQ:MRNA) that millions of Americans have already received. However, the advances in fighting the pandemic aren't limited to just vaccines. In this Motley Fool Live video recorded on Feb. 1, 2021, "The Wrap" host Jason Hall and Motley Fool contributors Keith Speights and Danny Vena discuss one big COVID-19 story that has nothing to do with vaccines.

Danny Vena: So I guess the last question here is, are there other big stories out there on the COVID front. Things that are going on that maybe we don't know about or things that we should perhaps keep an eye on.

Keith Speights: Yeah. There's one really, I think a big story that may be not quite as big as Johnson and Johnson's and Novavax's news, but it's up there.

Regeneron (NASDAQ:REGN) last week announced results, interim results from earlier results for late-stage study of an antibody cocktail, and they were using this cocktail to prevent COVID infection in people who have been exposed to it. People who are living in a household where one of their family members did have COVID. They hadn't been diagnosed with it yet, but they received this antibody cocktail as prophylaxis.

Now here's the cool thing. It prevented 100 percent of symptomatic infection. Basically, no one taking this antibody cocktail developed symptomatic COVID-19. Zero.

Danny Vena: That's impressive.

Keith Speights: We're talking about I think 186 participants. None of them developed COVID-19 and they've been exposed to it. All right.

Jason Hall: Known exposures, that's is the thing.

Keith Speights: Known exposures. Yeah. Regeneron's referring to this as passive vaccination. This isn't a vaccine, it's an antibody therapy. But it's very encouraging, and now about 50 percent, about half of the participants who took it did get infected. But it was asymptomatic infection and it went away in no more than a week.

To me, this is very encouraging. Now they're not going to have their final results, I think until maybe March or something like that, but this is something to really watch out for because it's an injection, and if everything continues to go well, in this study, we could see a very promising antibody cocktail on the market maybe by spring or summer. That could be very useful for folks who maybe haven't been vaccinated yet but have been exposed to COVID

Danny Vena: Just a quick follow up. What does that mean exactly, antibody cocktail versus vaccination. I'm not medically inclined.

Keith Speights: Sure. Let's just say what vaccines do Danny is they, well I want to take Moderna's vaccine as an example. But all the vaccines use a similar concept even though their approaches vary. Their idea is to make the body produce antibodies in response to what it thinks as the virus.

In Moderna's case and Pfizer's case, what they do is they put messenger RNA in the cells that tell the ribosomes to build proteins that are identical to the spike protein that occurs on the surface of the coronavirus. It just causes the body to mount that immune response.

What these antibody therapies are is they actually inject antibodies. They don't cause your body to produce antibodies, they put the antibodies into your body. Those antibodies fight the virus. That's the main difference between them. So Regeneron's isn't technically a vaccine, but it's accomplishing a similar goal as a vaccine. 

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