SARAH MCCAMMON, HOST:
A highly anticipated study of a COVID-19 vaccine has finally produced results. And the results are really, really good. The vaccine is made by the Maryland biotech company Novavax. And the study found that the vaccine was 100% effective against the original strain of the coronavirus and 93% effective against some of the more worrisome strains. Joining us now to discuss the latest results is NPR science correspondent Joe Palca. Good morning, Joe.
JOE PALCA, BYLINE: Morning, Sarah.
MCCAMMON: So 100% effective, that sounds pretty good - 93% against variants, not bad either.
PALCA: (Laughter) Yep. Yep.
MCCAMMON: What is different about this Novavax vaccine?
PALCA: Well, the vaccines all work by showing the immune system that looks like a virus but really isn't. And that something is called the spike protein. Now, in the case of the mRNA vaccines made by Moderna and Pfizer-BioNTech and the Johnson & Johnson vaccine, the genetic instructions for making that protein are sent into the body. And the body makes the protein. And then the immune cells say, oh, look; I've got to do something. That's the spike protein, looks like a virus. In this case, the Novavax vaccine sends the protein directly into the body, no assembly necessary. It gives it exactly the thing that looks like a virus but really isn't. And it's a technology that's been known for some decades now. And it's used for things like the hepatitis B vaccine and the pertussis - whooping cough vaccine. But, yeah, the results were pretty spectacular. I spoke with Novavax president for research and development Gregory Glenn about them. And here's what he said when I asked him how he felt about the results.
GREGORY GLENN: Well, great. I mean, it's good, exceeding my wildest dreams.
PALCA: Now, the study that we're talking about here enrolled 29,960 participants across 119 sites in the U.S. - the United States - and Mexico. And it was - two-thirds of the people got the vaccine. One-third just got a placebo. And they were counting cases from January through April. That's when they offered everybody in the study the vaccine. But according to - here's what Gregory Glenn said about the results again.
GLENN: We had no cases of moderate or severe disease. The only breakthrough cases we had with the vaccine were mild, so 100% protection against moderate and severe disease.
MCCAMMON: Joe, you talk about the effectiveness of this vaccine. What about safety? Does it compare in terms of safety to the other vaccines?
PALCA: Oh, yeah. Well, you know, all these vaccines have some results. You know, when you get the shot, you get a sore arm. You might get headache or chills. According to Gregory Glenn, a lot of the patients in - or a lot of the volunteers in this study, they didn't even know which they were getting, the vaccine or the placebo, which is a statement about how small the side effects were. And they didn't see any of the worrisome side effects you might have heard of about, you know, myocarditis or immune response, something strange. Those may turn up, actually, as the vaccine gets used more. But from this efficacy study and safety study, they've seen no signals that are worrisome.
MCCAMMON: So lots of good news here. Of course, there are already three vaccines available in the U.S. Why, Joe, have people been eager to see how this Novavax vaccine would perform?
PALCA: Well, as I say, it works differently than the others. And some people may find it easier to tolerate. So it has some properties that are attractive and should make it a useful addition to the ones that are out there.
MCCAMMON: Now that the results are in, what does that mean? Will people be able to get this vaccine soon?
PALCA: Well, no. There's still a regulatory process to go through. But they are hoping to start that early, as early as next month. And they'll be asking for regulatory approval around the world.
MCCAMMON: And quickly, how much is the company prepared to provide?
PALCA: A hundred million doses a month to start with, more coming later.
MCCAMMON: That's NPR's Joe Palca. Thanks, Joe.
PALCA: You're welcome. Transcript provided by NPR, Copyright NPR.