Pfizer (NYSE:PFE) and its German partner BioNTech (NASDAQ:BNTX) reported incredible efficacy data from a phase 3 trial for their mRNA coronavirus vaccine candidate last Monday. While the 90% figure inspired much hope, investors should know this was interim data that have not yet been peer-reviewed. This week, Moderna (NASDAQ:MRNA) reported equally impressive results for its vaccine candidate that takes a similar approach.

The Motley Fool sat down with Dr. Jeremy Brown, author of Influenza: The Hundred-Year Hunt To Cure The Deadliest Disease In History and Director of Emergency Care Research at the National Institutes of Health. Dr. Brown shared what these hopeful developments mean for the world and for investors.


Corinne Cardina: Hi there, Fools! I am Corinne Cardina, Bureau Chief of Healthcare and Cannabis on I want to let our viewers know that we're using a question-and-answer service called Slido. You can open that up on your browser. There's also an app and our code is "MFLive". You can submit questions, up there are other people's questions for ones you want to see answered. But I'm so excited to welcome Dr. Jeremy brown. Dr. Brown is the author of "Influenza: The Hundred-Year Hunt to Cure the Deadliest Disease in History". Dr. Brown is leading the National Institutes of Health office of Emergency Care Research. Dr. Brown, I know this is not your first interview with The Motley Fool, so welcome back.

Dr. Jeremy Brown: Thank you. It's really a pleasure to be back.

Cardina: Great. Fools, we're going to talk for the next 30 minutes about the coronavirus. We'll start with the latest on the COVID-19 vaccine development that was announced on Monday. Then we will talk more broadly about the pandemic and glean some of the learnings that Dr. Brown has to share based on his book and his experience. Let's start with the big news on Monday that everybody is talking about. We have Pfizer and BioNTech released a press release on Monday, gave the public new information about their COVID-19 vaccine candidate. An important thing to know is that this data has not yet been peer reviewed and we do not have the raw data. This was a summary in a press release, but a lot of experts are heralding this as proof of concept for vaccines that taken mRNA approach which is new. It's never been on the market before. Right now, the early data indicates that the efficacy, meaning that it accomplishes its goal of preventing COVID-19 is more than 90%. For context, the FDA had said 50% would be good enough to license. Dr. Brown, can you tell us a little bit more about what this really means? How encouraged are you by this new information?

Brown: Well, this is really a wonderful piece of good news that everybody I think is happy about. Imagine if the news would come out that it had failed, that would be awful for the prospects of a vaccine soon. But this news, even though it is preliminary, as you said, is exciting and it's optimistic. We do have to be careful as you pointed out, and as others have pointed out that, this is a preliminary press release which is not in any way a scientific review of what happened. Just to give people a context in this large study involving, I think over 30,000 or 40,000 people, the groups are split into two. Half the people got the Pfizer vaccine and the other half got a placebo, which is an inert equivalent if you like, a substance that is injected but is not actually the vaccine. They waited to see what would happen in a natural way to the people in the groups. How many in each group would actually come down with COVID. As you said, a success rate of over 50 percent reduction would have been meaningful to go ahead and actually produced this for everybody. but the results so far are that it is 90 percent effective. What we don't know is the following, is it 90 percent effective in all age groups and especially in the elderly? As we know, their immune systems often are a little bit harder to get energized and they sometimes actually they quite frequently require different kinds of vaccinations than the younger people. We don't know if it helps, specifically people in that age group. We also not sure of course, about people in specific with underlying medical conditions, whether it helped people in those age groups. Although, it certainly should. So good news all round and we'll have to wait and see.

Cardina: Absolutely. When that raw data is released, are there any particular safety or efficacy data points that you're going to be looking for?

Brown: Well, the safety aspect of it is, of course, critically important and it is something that is done before we reach this phase of the vaccine trials, is done in the very early stage. Phase I where it's just given to human volunteers. Maybe a dozen of the most or a couple of dozen to see if there are any side effects as you said. We just pass those stages and also smaller trials, the Phase 2 trials. But in terms of the safety of any drug, what we need are tail studies to follow these people who have gotten the vaccine for months and sometimes even years. Certainly, there have been examples of drugs which have been approved for the market and only a few years later was it discovered that they had dangerous side effects and were later pulled. Hopefully, that won't happen as well with this vaccine.

Cardina: Absolutely. We have mentioned that this is an mRNA coronavirus vaccine candidate. There's another company that's taking this approach, Moderna. Dr. Brown, is there anything you can tell us about how this is different from the traditional vaccine approach that we see with like a flu vaccine?

Brown: Sure. In the traditional approaches, what people do is they grow the virus and grow it in such a way that it is inactivated. There are different clever ways of doing this, but basically, you have what we could call a dead virus. Although, of course it's a question whether viruses are living in the first place, but let's assume that it's a living thing and it's killed. But its body is still there that is presented to the our body, to our immune system. The immune system learns what the virus is and so it's primed and ready should that virus return. That's what happens with influenza. A little bit more complicated with influenza though, because each year, there are several different strengths of influenza that are especially dangerous or especially likely to cause disease. We get the influenza vaccine, which contains three or sometimes four different subtypes of the influenza virus. Now with these other vaccines that we're now seeing from Pfizer, Moderna, others, they are using genetic engineering in a wonderfully clever way. Taking a small part of the messenger RNA and amplifying it in such a way that the human body learns to understand it. Then is primed in a way to that bit of the vaccine, if you like not to the whole vaccine, but that bit. That bit is enough of course, to allow our bodies to mount an immune response and fight the vaccine off should we become reinfected. It's the next version of vaccine development. Vaccines go back to the time of Louis Pasteur and Edward Jenner in the 1700s, smallpox and so on. But nobody has had the tools that we have to allow us to bypass many of the steps and go directly to building a vaccine based on the genetic makeup of the virus itself.

Cardina: Great point. I think one of the questions on everyone's mind is the timeline. Of course, the very first vaccine doses will go to the people on the frontlines, probably the demographics who are most at risk. What is your most realistic prediction for when a coronavirus vaccine might be available to the public?

Brown: I'm following what Pfizer itself says. I think there's no reason to think they don't get this right. But again, if assuming that the final studies demonstrate this effectiveness of upwards of 90 percent and the safety again, is verified. Pfizer itself has said that maybe we could get as many as 50 million doses this year. Many times that, perhaps into the billions next year. But as you've pointed out, the first people to get the vaccine should be the people who are, if you like, most in need of it. Now while we are all in need of it, it's some people who are on the frontlines of taking care of patients with COVID healthcare workers, as well as the elderly, and those with underlying medical problems that make them more likely to get the virus, excuse me. Those specific groups should of course be targeted specifically and early. Then the general population, those without special risks, factors or increased likelihood of exposure than they could come in the next release of the vaccine. We're all going to have to get in line and be patient as the vaccine is given to people who are most in need of it first.

Cardina: Definitely. I think a lot of us are of the mind that this is not necessarily a winner-take-all market. The first company that gets an emergency use authorization from the FDA certainly won't be the only company that has an effective and safe vaccine. Would you agree with that?

Brown: Yes. Look, the vaccine that Pfizer's developed shows us that you can jump-start the program. Vaccines typically take upwards of 10 to 15 to 20 years from the very beginning of their developments until they're finally released to market. Somewhere in the region of 90-95 percent of all vaccine trials that start at the very beginning fail. What the Pfizer experienced so far shows us is that those price statistics about the failure rate of vaccines are really exactly that. Perhaps we're now dealing with a different reality in which because of the ability to start building a vaccine directly based on the molecular and genetic structure of the virus, but those old failure rates may be a thing of the past. The other contenders if you'd like or the other approaches to building a COVID vaccine, that they also perhaps a slightly more likely now to actually be successful based on the Pfizer experience.

Cardina: Yeah, that's really promising news. Do you foresee any challenges with getting a vaccine to the masses? There's been a lot of noise made about the cold chain for the mRNA vaccine candidates. These drugs have to be kept insanely cold. Not all neighborhood pharmacies have the kind of refrigeration required, any thoughts on that? Is that something we should be concerned about?

Brown: Yes, that's right. People in the business of logistics called this the final mile problem or the last mile problem, which is you can build out your product, you can get it ready and distributing it down to the people who actually need it rather than having it locally or just the few distribution points. That's a big problem. This final mile approach is of course something that needs to be carefully thought out. I don't think it's a problem that it's insurmountable. But as you point out, the vaccine that was produced together with the German firm BioNTech, it has to be stored at something around minus 70 degrees Celsius or about minus 90 Fahrenheit. Now, that's a very cold temperature indeed. Other vaccines as people who know who have gotten that flu vaccine, for instance, this year will know that the flu vaccine is usually just kept in refrigerator. But it is certainly possible from my understanding of the capabilities of Pfizer, it's certainly possible to develop a storage unit that can indeed deliver a vaccine kept at this very cold temperature. Even it maybe possible to do this in other less industrial countries as ours, what we call third world countries, where the ability to keep the product cold might be more challenging. But my understanding is that even in that setting, the Pfizer is confident that it can keep the product cold enough for it to remain active if you like, and can start be given appropriately. It is a problem. It will be very interesting to see how it is played out. But I think that it's a problem that is not one that is instrumental.

Cardina: That's good news. What would you say the biggest misconception about coronavirus vaccine says it's out there that we should correct?

Brown: Well, that's a very interesting question. I guess, the answer is we don't know a lot about coronavirus vaccine yet because we don't have one. But let me take a look at the influenza vaccine, which we've had for upwards of 50 years now. One of the problems with the influenza vaccine as I mentioned a few minutes ago, is that there are lots of different strains of influenza around. That means that each year we have to change the vaccine so that it incorporates the three or four most likely strains of influenza. That's a problem and that's one of the reasons we need to get the vaccine each and every year. Now, will this vaccine, the Pfizer vaccine, will this also have to be given on a yearly basis, or will our immune system remain vigilant and prime based on what appears to be a two-dose regimen? In other words, you going to have to get the vaccinated once and then come back a few weeks later and get the second dose. This by the way a common way of giving child with vaccines, often have to be given in two or three separate doses. But the question is whether will our immune system remain prime against the coronavirus or whether you will have to get this on a yearly or every five or ten years like for instance, the Tetanus vaccine, which you need every ten years or so. That's one of the questions that we have and of course the other question is different strains of coronavirus. Does this messenger RNA technology that Pfizer is using, does this make it a vaccine that will be active against different coronavirus strains as they mutate? Or will you have to sort of develop a new one for each strain in the way that we do for influenza? I think as somewhat of an open question as well, and we will just have to wait and see what the signs tells us.

Cardina: Absolutely, we will stay tuned. I have a question for you. We are all investors on Of course, you're doctor, so I'm going to try to keep it as general as possible. But what would you say to anyone who might be considering buying stocks of companies that are involved in the coronavirus vaccine landscape.

Brown: Well, if you look at my investment portfolio am the last person you really want to ask those questions to. It's certainly a huge market here. The question will be, of course, stock prices, are they already at their peak based on the news and any small amount of bad news if you like, on news that isn't pristine, will that fake stock price? It's certainly possible that we see hiccups along the road when the full data is released, it turns out that the vaccine is not as effective for example, in older people and that might be a problem for that segment of society networks with younger members of the society. The news, though encouraging, is not final and as to whether or not Pfizer stock is at its peak based on this or is only going to go up. Well, I have no idea.

Cardina: Absolutely. We need to be paying attention to valuation for sure in this sector right now. Looking beyond Pfizer and BioNTech, are there any other near-term catalysts that investors should be keeping an eye on any upcoming trial data? What are you going to be watching?

Brown: Well, there are, I think around nine or 10 Phase 3 trials across the world that are currently running. So we have to wait and see what they show. They will use slightly different approaches and new Phase 3 trials are being announced all the time. One good piece of news is the fact that if Pfizer could do it in a short amount of time, as I said earlier, it is likely to mean that other companies are also going to be able to produce something. But which of those and how long it's going to take and which of those vaccine trials in Phase 3 will fail? That's an open question, as I said, if you look historically, at least 90% of all vaccine trials fail, if you look from the very earliest development of the vaccine all the way through to Phase 3. In terms of Phase 3 trial failure rate somewhere in the region of half of them may fail. We don't know again, if those are statistics based on what has happened in decades that have passed where the vaccines were not built in this laser-sharp focused way, or whether that failure rate is going to be a thing of the past that because we are now building vaccines with this amazing technology. The old failure rates in the old statistics about who is likely to succeed and fail maybe they're a thing of the past now. It could be the candidates that get to this final stage of testing with these newer techniques are actually far more likely to succeed. Again, we'll have to wait and see what happens with these other dozen or so Phase 3 trials, before we're able to look back over our shoulder in the rearview mirror and say, going forward, I think that new vaccine trials will have a success rate not of 10% but of 60%. That would change things greatly, certainly for people who are looking to invest in the companies that produce them.

Cardina: Absolutely. To borrow from the investing community, past performance may not indicate future success in this, thanks to all these technological advances. I'd like to get a little bit more general now, I want to hear about influenza. You, of course, did an insane amount of research for your book about influenza. I'm curious, what is still relevant for today's pandemic that you've learned 100 years after the influenza pandemic?

Brown: Well, as you said, I wrote this book in influenza that came out two years ago now, seems like forever or two years ago in 2018, which the 100th anniversary of the great influenza pandemic of 1918. I looked at what had happened over the last 100 years. I did tell the story of what happened in 1918, which is very sobering of course. Fifty to one hundred million people died across the world, 675,000 people in the United States died, which is the equivalent in today's population of about three million. So it was far more deadly, at least in terms of numbers than the COVID pandemic is so far. Let's hope that COVID pandemic does not catch up to that awful number of deaths in the US and across the world. But influenza does remain, of course a perennial challenge for us. We are still trying to find that vaccine that can be given once and once only that will cover all different types of influenza virus, all the different viruses, across the world they differ from each other. So you can get a vaccine that's given once, it'll be good against all the different kinds of the virus and it will last for many years. Just given a vaccine each year is a problem because people have to remember and they have to come back. If we can have a vaccine that will give us the long-term protection that for instance, the MMR, Mumps, Measles, Rubella vaccine gives us that would be an incredible breakthrough as well. We don't have that yet, with the influenza vaccine. Influenza each year in the United States kills anywhere between 12,000 and over 100,000 people each year. We don't have good statistics about it simply because it's very difficult for everybody to agree on whether a death is caused by influenza or secondary pneumonia from influenza or heart failure caused by influenza in older people and younger people. It's unfortunately easier to decide that this was a death directly from influenza. So we have a very wide range of estimation of the number of people who died. Certainly, the very beginning of the outbreak of COVID people were mourning. I think I was one of them as well. We said, look, so far, this was in January time, the enemy is influenza rather than COVID. Now of course, we know that that changed very quickly. But influenza certainly remains a challenge for all of us. What I am hopeful for is that because of the precautions that all of us are or should be taking with mask and hand washing and social distancing, that the influenza numbers actually will be way lower than they are in a normal year. We would expect that because influenza is passed in much the same way as COVID is passed on droplets. If you're not in the office or on the bus or on the subway being sneezed on by other people who have it, then you're less likely to get it. So one would expect that when the dust settles and we're able to look back at the flu season last year initially, we will actually see a decrease in the number of deaths from influenza. That of course, will again remind us that every year we need to be taking these precautions, COVID will go away eventually, either through a vaccine or through the natural process, all pandemics come to an end. The question is how much damage they can cause while they are active. But when COVID has gone away, I think that we will be able to learn and remind ourselves that just taking these very basic precautions, it's not only good for reducing the risk of COVID, but it's also a very good way to stay healthy over the winter to more flu and other winter viruses. Couple of wonderful studies that were done in which kindergarten children were put into different groups. One class would wash their hand several times a day and the other class would not be told to wash their hand several times a day just as needed. When you compare the two different groups, of course, the kindergartners who washed their hand several times a day had a much lower absentee rate because of virus infections and so on. That's just a little morsel that remind us these very basic precautions that we're all now taking are good, not only for COVID, but for all of the winter viruses.

Cardina: Absolutely. I also hope that people will be more likely to take the flu vaccine this year. We don't have a coronavirus vaccine yet, but what we do have will also help you stay healthy.

Brown: That's right, especially in those members of the population and your listeners who are especially vulnerable, that's the elderly, that's people with underlying medical conditions. Women who are pregnant are also at increased risk of complications of flu. So it's especially important in those vulnerable populations. But of course, the rest of us also should really get vaccinated.

Cardina: Definitely. My last question for you is about those winter months that we just discussed. Of course, we have some holidays coming up. Canada already celebrated their Thanksgiving holiday and their cases went up afterwards. The U.S. is heading in a bad direction. Do you have anything to share about how we should be approaching the coming winter months, the holidays, in the best ways to protect ourselves?

Brown: Yes unfortunately, as you pointed out, the virus is really rampant now not only in North America, but also across Europe. If you've been paying attention to what's going on, England recently entered its second or third full lockdown. Because of the uptick. Much of this is expected to be quite honest. All of the winter viruses are winter viruses, because they do better that time of the year. They don't like the warm, humid weather. They prefer cold, dry weather. They're more sensitive to that warm climate and they reproduce better, they live as well longer in those cold winter climate. I think anybody who knows about the winter viruses would have expected to see this uptick. But the question is to whether we should be getting together with our loved ones for Thanksgiving, I think is something that each family needs to really think about. It's so easy to spread this virus right now. The last thing that anybody wants to remember their Thanksgiving of 2020 for, is that they passed on a coronavirus to grandma or grandpa and that person then died. It would be a horrible Thanksgiving indeed. I would really ask people to decide whether the risks of meeting up with loved ones are really worth of the dangers. It's true that the overwhelming majority of people get COVID and are just fine. But we've experienced over a quarter of a million deaths here in the US. Even though the overwhelming number of people who get coronavirus do well, because of the sheer numbers, we have this terrible mortality. What I hope that people will think about is even if you're going to get together as a family, if there are people within your family who are older, and certain people who are immunocompromised, people who have underlying medical conditions, that would mean that they are more likely to come down with the virus. Skip that this year. Let them Zoom in. We have the technology, have a virtual Thanksgiving dinner. Next year, hopefully we will be able to come together with all of us having safely been vaccinated and we'll be able to tell the story of our virtual Thanksgiving dinner while remaining healthy.

Cardina: That's so great, very optimistic view of what's going to be some tough choices for everyone. But thank you so much Dr. Brown. Fools, make sure you check out his book Influenza: The Hundred-Year Hunt To Cure The Deadliest Disease In History. Dr. Brown, thank you again. We will keep in touch and I hope you stay safe.

Jeremy Brown: Thank you, Corinne, you too and happy Thanksgiving to everybody.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.