ARI SHAPIRO, HOST:
There is good news today about coronavirus vaccine research. Two of the leading experimental vaccines are showing promise in large studies. Reports published in The Lancet don't demonstrate that these vaccines are safe and effective, but the groundwork is now laid to find out. Joining us to talk about this is NPR science correspondent Richard Harris.
Hi, Richard; nice to have you joining us with some good news today.
RICHARD HARRIS, BYLINE: Hey, Ari, yes, indeed, nice to be with you.
SHAPIRO: Yeah. Tell us what these studies show.
HARRIS: Well, one comes from a Chinese research group based in Wuhan. They tested their experimental product on more than 500 people and showed that it provided a promising immune response without any major side effects. The second study is even bigger, involving more than a thousand people. I spoke to Adrian Hill who is principal investigator of that study, which is out of the University of Oxford in the U.K.
ADRIAN HILL: The vaccine's safety, as we had hoped, looks fine - usual vaccine side effects but nothing serious. And perhaps more importantly, the immune responses that we're measuring in the people vaccinated look rather encouraging.
HARRIS: Hill says most people who got the experimental shot developed antibodies that neutralized the virus at least in the lab. Their immune systems also produced custom T cells, which is another line of defense.
SHAPIRO: And what does that translate to in terms of, like, the ability of this experimental vaccine to actually prevent disease?
HARRIS: Right. It doesn't answer that question directly, but it is a good sign for sure. If the vaccine hadn't triggered these reactions, it would have been a big setback. Unfortunately, though, the only way to find out whether a vaccine works is to give it to a lot of people who are at risk for infection and then finding out if they're protected.
SHAPIRO: Have those kinds of big studies started yet with the Oxford vaccine at least?
HARRIS: Indeed, they have. Scientists have already given the experimental vaccine to 10,000 people in the U.K., Hill says, and they're starting to expand their studies in South Africa and Brazil.
HILL: And we anticipate in the next few weeks starting a much larger trial still of about 30,000 subjects in the U.S. led by AstraZeneca, our commercial partner.
SHAPIRO: So that's very good news about this experimental vaccine. But we've heard about dozens of potential vaccines for the coronavirus. Where do these two fit into the big picture?
HARRIS: Well, I would say these two are at the vanguard, especially with these two big studies now published. They both use a similar technology. It's a vaccine based on the idea of modifying a harmless virus with a bit of the coronavirus to trigger this immune response. You know, the strategy has been tested a lot for other diseases, which is why it was able to move so rapidly through the U.K.'s approval system. But that said, there is not a long track record for this technology. Vaccine specialist Naor Bar-Zeev, who is at Johns Hopkins, says these results are indeed encouraging. But he's also glad to see that there are other vaccines using other strategies in the works.
NAOR BAR-ZEEV: You never know what pitfalls lie ahead. It's a bit of a hurdle, that race, you know, to clear lots of hurdles. And so often it's good that there are many candidates because we know that not all of them are going to end up at the finish line.
SHAPIRO: OK. So speaking of the finish line, any guess how soon there could actually be a winner in this race, I mean, assuming that there is a winning vaccine that's actually safe and effective?
HARRIS: That's right. Well, I put that question to Adrian Hill at Oxford who laid out a best-case scenario for me.
HILL: If we got a result in, say, October and we had emergency use licensure (ph) by November, we would certainly hope to have many millions of doses available then in different countries from different manufacturers
HARRIS: The company working with Oxford hopes to have 2 billion doses ready to go in a year. But, you know, that's not enough to protect everyone on the planet. So it's another good reason to have a lot of other companies pushing hard on multiple fronts.
SHAPIRO: NPR science correspondent Richard Harris.
Thank you.
HARRIS: Anytime. Transcript provided by NPR, Copyright NPR.
