Some Questions On The Future Of The Coronavirus Vaccine, Answered

May 8, 2020
Originally published on May 8, 2020 5:12 pm
Copyright 2020 NPR. To see more, visit https://www.npr.org.

MARY LOUISE KELLY, HOST:

The global race for a coronavirus vaccine is on. And around the world, hopes for a vaccine are high.

(SOUNDBITE OF MONTAGE)

UNIDENTIFIED REPORTER #1: Tests on humans are already underway in the U.S., China, the United Kingdom and Germany.

UNIDENTIFIED REPORTER #2: The time that it takes to do these things is being at a level that no one has ever seen.

UNIDENTIFIED REPORTER #3: Good morning, Andrew. Pfizer and its German partner BioNTech starting the dosing of the first U.S. participants in their clinical trial.

UNIDENTIFIED REPORTER #4: And, Jim, Moderna is going to be a talking point this morning. FDA approval for phase 2 trial of its vaccine candidate, mRNA...

KELLY: So what is a realistic timeline for a coronavirus vaccine, and when might we, the public, actually be able to get it? Well, those are the million-dollar questions that NPR science correspondent Joe Palca is here to address.

Hey, Joe.

JOE PALCA, BYLINE: Hello.

KELLY: So we have heard so many target dates for when we might have a coronavirus vaccine. We've heard Dr. Fauci, Anthony Fauci of the White House task force, saying maybe by January. Drug companies are giving similarly optimistic timelines. But just to be clear from the start, getting a vaccine together by January, that would break, like, every record on the books, right?

PALCA: Yes, it really would. And it is seem likely - it does seem likely at this point that there will be a vaccine faster than ever before. That does seem to be the case. But there's only some things that you can speed up, and others, not so much. The bureaucracy - I know that the Food and Drug Administration is going to be evaluating the various stages of testing with great speed in this case. But you have, first, to prove a vaccine is safe, then you need to prove it generates the immune response you want, and then you need to find out if it actually prevents people from getting sick if they're exposed to the virus.

KELLY: And how would they know? I mean, in a lab, how would they know if they have developed a vaccine that works?

PALCA: The way you know that the vaccine is effective is that you give a vaccine to one group of people and a placebo, or an inert injection, to another group, and you see if they come down with the illness. Now, they're only going to come down with the illness if they're exposed to it. So how are they going to get exposed to it? Well, if there's a lot of virus circulating in the population, that's one way. Another possible way that people have talked about is actually giving them the virus on purpose and seeing if the vaccine prevents them from getting sick.

KELLY: Huh.

PALCA: It's a kind of a funny conundrum because you want people to be exposed because you need to know if your vaccine is working, and you don't want them being exposed in another sense because you don't want them to get sick. So it's kind of a problem.

KELLY: Let me turn you to a parallel challenge, which is, say you've got a vaccine, and you think it's going to work. Then you have to manufacture this thing, right?

PALCA: Yeah, absolutely. And I spoke with Emilio Emini about that. He's been working on vaccines for decades. Today he's with the Bill & Melinda Gates Foundation. And I should say, Gates is one of NPR's funders. He put the issue this way.

EMILIO EMINI: The requirement to scale up to the kinds of numbers we're talking about within the short timeframe that we're speaking about would be an extraordinary effort.

KELLY: Joe, stay with that point for a second because I have been wondering. I mean, all kinds of businesses scale up manufacturing things all the time. Why is this such an extraordinary effort to scale up a vaccine?

PALCA: Well, the tools that you need for a vaccine manufacturing plant vary considerably depending on the kind of vaccine you're making. But in many cases, you need something called a bioreactor, which is a giant tank that allows the organisms that are actually spewing out the vaccine of interest to grow. And sometimes you could be talking about a 200,000-gallon bioreactor, and you're not going to go down to your local hardware store and pick one of those up. So that's one issue. There's specialty equipment that has to be made.

Fred Porter is another vaccine expert. Now he's with the gene therapy company Adrenas Therapeutics. And he says in addition to the big stuff, there's little stuff like medical grade glass.

FRED PORTER: You have to put a product into a sterile vial or syringe, and there's only so much of that glass to go around. And if we're thinking about billions of doses to be able to deliver vaccines around the world, that becomes a significant bottleneck.

KELLY: That raises the question of what the role of the federal government is here in trying to unclog that bottleneck. Should the federal government be taking the lead in preparing for the manufacture and distribution of a vaccine?

PALCA: Well, somebody is going to have to do some sort of organization. And it's particularly an issue of getting the vaccine to people who don't maybe have the wherewithal to pay for it or don't have the medical infrastructure to develop their own vaccine.

Seth Berkley, he's the CEO of an organization called Gavi, the Vaccine Alliance, and he says that it's not an issue that you can decide by one country at a time.

SETH BERKLEY: We're not going to be safe as a world unless everywhere is safe. So even if we had parts of the world that would have low spread or no spread, if you had large reservoirs of the virus in other places, of course you have a risk of reintroduction.

PALCA: And so it's really going to be the case that everybody is going to have to figure out a solution for this together. And that's going to be tricky.

KELLY: Well, and - I mean, just to your point about everybody trying to figure this out, there are something like more than 100 vaccines in development all over. Safe to say, the majority of them are never going to become viable candidates. They're not going to succeed.

PALCA: And they may not succeed for a variety of different reasons. I mean, they may work, but they may be too hard to manufacture, or they may not work. I mean, there's a lot of reasons, but that's not surprising. I mean, at this stage of development, many are expected to fail.

KELLY: Is one possible scenario, Joe, that we don't just get one vaccine but that multiple vaccines are developed that might work even in somewhat different ways?

PALCA: Yeah. I think that's actually kind of likely. I mean, there are multiple approaches to making vaccines that have advantages and disadvantages. Some are tried and true and have worked for other viral illnesses. Some you can make much faster and may work and may be available faster, but it's unclear that they'll be as effective. I talked to Emilio Emini of the Gates Foundation, and he says developing multiple vaccines in parallel is a good thing.

EMINI: It's my perspective that this is going to require more than one successful vaccine. It's going to require at least several, if not more, that are successfully developed in parallel so that the scope of what will be needed can be satisfied.

KELLY: Do we know, Joe, if the coronavirus vaccine is going to look closer to the flu vaccine we're all supposed to get every year, which we know they change every year because the virus changes every year, or will it be something more like the measles or the polio vaccine, which my understanding is they're fixed?

PALCA: It's a good question. And unfortunately right now, the answer is, it's not clear. There is some indication that this virus doesn't change very rapidly. And so if you find a vaccine that works against it, it may work in perpetuity. But we also don't know how long immunity to this virus lasts. So it may be that we need to get booster shots, not a different shot every year but a booster of the same shot, to make the vaccine actually work for multiple years.

KELLY: So to the central question, the basic question at the heart of this, I mean, how hopeful should we be that there will be a vaccine that works, that we can get our hands on by next year?

PALCA: It's hard to say. I mean, there are good reasons for optimism, but vaccine people will tell you that every time you start working on a vaccine for a new virus, you don't know what the hurdles are that you're going to have to overcome. So obviously there's a lot of work that needs to be done before we can answer that question with any certainty.

KELLY: That is NPR's science correspondent Joe Palca on what we know and what we don't know about the race to develop a coronavirus vaccine.

Joe, many thanks.

PALCA: Oh, you're welcome.

(SOUNDBITE OF KIASMOS'S "BLURRED") Transcript provided by NPR, Copyright NPR.