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NIH Vaccine Chief Optimistic on Prospects for SARS-CoV-2 Vaccine
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Video summary and transcript by Mark Mascolini
In a video by fivethirtyeight.com editor Anna Rothschild, the director of the Vaccine Research Center at the US National Institutes of Health, John Mascola, says, "I am quite hopeful that we will . . . find a vaccine that works [against SARS-CoV-2] in the time frames that people like Dr. Fauci have been talking about [within 18 months]. . . . I think the data we have from the laboratory side of things suggests that a vaccine should work against a coronavirus."
The Rothschild video, "How Close Are We to a COVID-19 Vaccine?", can be viewed online at https://fivethirtyeight.com/videos/how-close-are-we-to-a-covid-19-vaccine/
or assessed via the following slightly abbreviated and edited transcript. These are the key points:
• A phase 1 trial of a SARS-CoV-2 vaccine has begun, the fastest a vaccine has ever entered clinical trials in the United States.
• The tested vaccine is an mRNA vaccine, and if licensed it would be the first mRNA vaccine against a human disease.
• mRNA vaccines are easy to design and make in quantities needed for human trials, but no facilities are set up to produce large quantities of an mRNA vaccine right now.
• The new coronavirus does mutate but not as fast as HIV mutates, for example. So Dr. Mascola does not expect that SARS-CoV-2 would mutate away from a vaccine within months or years.
• Preliminary reports have circulated about some recovered COVID-19 patients producing very low levels of antibodies. That might mean that some people could get COVID-19 more than once.
• Dr. Mascola said that should not affect prospects for coronavirus vaccine efficacy, because such a vaccine would be designed to promote a strong immune response.
Anna Rothschild (fivethirtyeight.com senior editor): Dr. Anthony Fauci [of the National Institute for Allergy and Infectious Diseases] says it will take a year to 18 months to make a vaccine for COVID-19. We still don't have a vaccine for HIV. Will we be more successful with COVID-19? And how are scientists going about it?
A vaccine just entered a phase 1 trial in Seattle, the fastest we've ever got a vaccine into trials in America.
Dr. John Mascola (director of the Vaccine Research Center at the National Institutes of Health): The reason we could do that so fast is the scientific community had been working on vaccines for SARS and MERS and had been thinking about the fact that another coronavirus could emerge.
Rothschild: Scientists had already been working on a vaccine for MERS that targeted the spike protein on the virus's outer coat. This gave scientists a head start in making an mRNA vaccine against SARS-CoV-2. Take a snippet of the virus's genetic code, just the part that codes for the spike protein. That gets injected into a person, making the person's immune system start producing the harmless coronavirus spike protein. In theory this helps a person build up an arsenal of weapons against a real SARS-CoV-2 virus if they ever encounter it in the future.
Mascola: We've already made mRNA vaccines in the lab for SARS and MERS.
Rothschild: The beauty of the mRNA vaccine is that they're easy to produce. But there are some drawbacks to this type of vaccine.
Mascola: So far there are no licensed RNA or DNA vaccines. So we still have to prove that this technology will work against SARS-CoV-2.
Rothschild: Will that make it harder to scale up production because there are fewer facilities that have the capability to make this kind of vaccine?
Mascola: The main challenge is that it hasn't been scaled up before. Other vaccine platforms have been scaled up before, so there's experience doing it. A lot of funding activity has been put into that question of scaling up.
Rothschild: But we're not at the manufacturing stage yet because we don't even know if this vaccine works. Dr. Mascola told me various scientific agencies in the US aren't pinning their hopes on this one trial and are considering vaccines using a number of different platforms.
But is a vaccine against SARS-CoV-2 even possible? There are certain viruses like HIV that mutate quickly and change the proteins that coat them. The minute your body learns to identify and fight the virus, it changes again.
What do we know currently about the speed with which this virus (SARS-CoV-2) changes and if a vaccine will actually be able to provide long-term immunity?
Mascola: We know a little bit and so far the data are encouraging. We know generally speaking that coronaviruses can mutate. But the rate of mutation of the new coronavirus seems to be at a level where we wouldn't expect it to mutate away from a vaccine in a short time frame of months or years.
But we'll have to keep an eye on that. There will be a whole group of medical epidemiologists that would track the [genetic] sequence of the virus over time and look for any changes. If those changes do occur, it will not necessarily mean we can't adjust. We can with vaccine technology adjust the vaccine if needed, include a second [viral] strain if we need it. So I don't think that will hold us up dramatically. It's something that we will have to keep a close eye on.
Rothschild: How hopeful are you feeling right now about what we're doing to make a vaccine and otherwise stem the spread of coronavirus [infection] in the US?
Mascola: I am quite hopeful that we will get a vaccine and find a vaccine that works in the time frames that people like Dr. Fauci have been talking about. There is a huge US government and public and private partnership effort in the US and around the world. Scientists working together, agencies working together, private companies and government working together. There are many handfuls of vaccines that are being developed. And I think the data we have from the laboratory side of things suggests that a vaccine should work against a coronavirus. So really we just have to prove it and we have to make a lot of it, and I'm pretty confident that we will get there.
Rothschild: Since I spoke with Dr. Mascola there have been some preliminary reports that some recovered COVID-19 patients have produced very low levels of antibodies. Those are the proteins that your immune system uses to remember and fight against a germ. In theory that might mean those people could get COVID-19 more than once.
I asked Dr. Mascola whether that would change our prospects for a vaccine since a vaccine teaches our immune system which antibodies to use to fight a particular virus. He told me over email that there's probably variability in peoples' reaction to getting COVID-19 but that a vaccine is designed to promote a really strong immune response. Depending on the platform you might need a few doses several weeks apart, or you might have to re-up your vaccinations every few years or decades, similar to what you do with other vaccines. But that's why those human trials are so important so we can figure out what's actually required.
If you have a question about COVID-19 or the process for creating vaccines, please let me know. And if you
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