WHEN: Today, Wednesday, December 16th

WHERE: CNBC Healthy Returns Livestream

Following is the unofficial transcript of a CNBC interview with Dr. Moncef Slaoui, Operation Warp Speed Chief Advisor, and CNBC’s Senior Health and Science Reporter Meg Tirrell live during the CNBC Healthy Returns Livestream today, Wednesday, December 16th. Full video will be available at cnbc.com/healthy-returns.

All references must be sourced to CNBC Healthy Returns Livestream.

MEG TIRRELL: Welcome back everybody and thanks for sticking with us for this very special Healthy Returns Livestream. This, of course, has been the series throughout this year where we’ve talked with public health experts, researchers, the people who are helping us understand and get through this pandemic. I’m Meg Tirrell, CNBC’s Senior Health and Science Reporter and our guest now is Dr. Moncef Slaoui, Chief Scientific Adviser to Operation Warp Speed and one of the major reasons we are talking about records being shattered in modern medical history for the speed with which these vaccines or this pandemic have been developed. Dr. Slaoui, thanks for being here.

DR. MONCEF SLAOUI: Hi Meg. Thanks for having me.

TIRRELL: Well, why don’t we start with the news this week of course the Pfizer/BioNTech vaccine is going out across the US. From what you’re observing, how is the rollout going so far?

DR. SLAOUI: Well, touch wood up to now it’s going frankly very well. Distribution has now taken place to all 636 locations that we have identified and were given to us by the states. There have been reports of very small damages to the, to the boxes and things like that but not a single vial of vaccine lost or destroyed. You may have heard this morning in our press briefing that there were two pizza boxes as we call them of 975 doses of vaccine that had a temperature excursion downwards, colder than minus 80 Celsius, minus 92, which have been returned and are being assessed within Pfizer to make sure that they’re whether they’re okay or not. Other, other than that event frankly up to now it’s been excellent. And I would say on the, on the emotional side of things, seeing people being vaccinated, seeing the emotions that people were expressing and also seeing the recent polls suggesting that there is a much higher or improving acceptance of vaccination in the population, some of them even suggesting 70% or 80% of people now saying they, they would consider taking the vaccine, I think it’s very heartwarming and promising for the future so up to now going well.

TIRRELL: I think one of my favorite videos from the first day we’re seeing those healthcare workers in Boston literally dancing in the street at getting these, these vaccines and vaccinations to help really end this pandemic. I want to ask you about the challenges of this vaccination campaign that we’re now embarking upon. Are we actually able, at the last mile level to administer this vaccine to so many people millions of people so quickly?

DR. SLAOUI: So, you know, the benchmark we have frankly is the flu vaccination once a year. 80 million to 100 million vaccine doses distributed and injected in a period of probably five to six months. So here we’re talking about double to triple that. I think it is within reason to say that it’s an achievable objective. There is such a level of awareness, such a level of motivation and commitment and resilience in the system that, you know, our expectation and our hope is that it’s, it is going to work. I’m sure I’m sure Meg there will be instances where people were expecting to be vaccinated and, and they had to come the next day or things like that. But I think we need to look at the 90% of the story at the same time as we look at 10% or 5% or only 1% of the story. But, you know, it’s never been done. So, clearly there is a first time and the key assumption we made was let’s not invent something that’s never been tested. Let’s use all the path that’s being tested every year and let’s enhance it rather than invent something else and I think that’s a reasonable approach, minimizes the risk.

TIRRELL:  What does this start to look like for Americans as more vaccine becomes available. Give us your expectations for the timing of when different groups will be able to get access and when the general population will be able to, and then what does that vaccination campaign look like I mean, here in New Jersey, I’ve heard from my county already I’ll be getting my vaccine in a Kmart in, you know, the nearby town, it’s an empty, you know, big building so what is this going to look like for everybody?

DR. SLAOUI: So, I mean it’s may very much depend from one state to the other since, you know, that is the definition exactly, but I would say the following. First, I think there will be people for whom vaccine comes to them and people that go to the vaccine. And in the highest risk population, vaccine is going to be coming to them, whether it’s the healthcare workers, whether it’s people who are living in long term care facilities, whether it’s a whole series of first line workers. I think those people will have vaccine coming to them that’s compatible also with mass vaccination strategies and those, those will be the first flavors, I would say, as a majority of people immunized as you know, those categories of people if I add to them the people who are over the, over the age of 65 represent about 120 million people in our population and our plans is to be able to immunize 100 million of these people with two of those vaccine by the end of the first quarter of the year 2021, somewhere during the month of March and I say somewhere during the month of March because in the second half of February and in March, we will have a third vaccine we hope based on our plans and how they’re progressing up to now. We’d have a third vaccine, the Johnson’s (J&J) vaccine, that’s a one shot vaccine and, and if it is effective and if it is approved, it will help us accelerate even faster that covers the population. I think during that same period, maybe as of the month of February, some vaccine doses will start to be available or maybe even earlier but in significant numbers. In February, it will become available in the CVS and Walgreens, where people will be, I assume, asked to go and get vaccinated and people, for instance, people that are over the age of 65 that are living on their, you know on their own, independent, independence and, and then in the second quarter of the year 2021, mass vaccination of the general population can start and a very important point there is actually if, if one subtracts, the 70 to 80 million people who are below the age of 18 in the United States and let’s say more or less the 20 million people that unfortunately may decide not to be vaccinated for whatever reason, either because it’s contraindicated or because they have decided they don’t want to be vaccinated, we’re talking about immunizing 220 or 230 million people, of which 120 out of the high risk population, and 100 million are next, much lower risk adult population. I think that population will definitely go through in the month of April and May and then it’s going to depend when you know beyond the age, 16 to 18, when the trials that have started, the first one started today or yesterday evening, for instance, Moderna trial, driving the age down into the adolescent population to the age of 12, and then the age of five and then the age of toddler. And those may come in May, but they may, better data may come, you know, gradually between the month of May and the month of September to go all the way down into the ages.

TIRRELL: I want to ask you also about what lies within this month and we’ve heard you say, there’ll be enough for 20 million people by the end of December, and you’re also talking about 40 million doses being available by the end of December, but just looking at the math that’s happened so far, 2.9 million doses from Pfizer/BioNTech went out this week. If Moderna gets clearance, almost 6 million of Moderna’s vaccine will go out next week, I think I heard General Perna today say 2 million of Pfizer’s doses will also go out next week, that only gets us to around 11 million doses, with one week left of December, are we going to make the 20 million people or 40 million doses?

Dr. SLAOUI: So the plans is for Moderna expressed to have 20 million doses, which we know are already produced and filled. This is why the level of confidence is much higher. It’s a matter of the last, the last step in the quality control criteria which is the longest hole in the 10th, which is a sterility test. So, of course, until that test is available you cannot use the vials but that those vaccines are physically here and exist. 20 million doses Pfizer that it’s a little variable somewhere between 12 and 15, or 17 million doses, it’s really going to depend really by the day on how batches are released that that’s, this is a frankly one of the challenges around communicating the number of doses. The way we look at it here internally is as a cadence of, if I take, if I take for instance Moderna where we have a much more granular visibility on the manufacturing output as compared to Pfizer, the, you can calculate more or less, that every day, more or less, a million doses of vaccines are produced, and then filled, filled and finished, and then quality control released. When you are very early into the process, you know, you’re, you’re, you know, the first day was a million and a half doses today and then it was .4 million doses tomorrow and then it was 1.3 million doses day after, etc. But as you get into a cadence and we express it in weeks, we say okay well it’s about 7 million doses every week and we will be shipping vaccines once a week giving, giving a forecast and a plan to each one of the states and some weeks we may have 7.3 million doses and the next week we may have 6.4 million doses, but you adjust your, your cadence to really give a reasonably constant number of vaccine doses and after frankly after three or four weeks, that cadence will have set itself and our capacity to predict with much higher precision the number of doses that’s coming out will be, will be much higher but what’s happening here is the world is discovering with us together how manufacturing of a very complex product happens, which is, you know, you, you ramp up, scale up, we couldn’t create a stock before starting to use this vaccine because it would be unethical to hold it back. So we’re going to frankly learn this together and we are giving numbers as our high true, somewhat risk adjusted and then we will be transparent about what happens with them. Some, some months we may have a little bit more and some months we may have a little bit less.

TIRRELL: So, that last week of December, do you think it’s going to make up that difference with the 40 million doses or are we just saying, should we stick with 20 million people getting their first shot in December I guess is the question.

DR. SLAOUI: I mean, honestly, listen until last week, the commitments from the company from the companies were slightly more than 20 million for Pfizer and slightly less than 20 million for Moderna and now it’s 20 slightly more for Moderna, and a little bit less than 20 for Pfizer and that’s what I’m saying is, like, as we go on a daily basis, batches are made, filled, released so the plan is for 40, probably now the plan is for 37. But, yes, you’re right. The key point, which is frankly my preference is to talk about people immunized because that’s what counts. We can immunize 2 million people by the end of this month and give them a second dose within the month of January, as well as immunize another 20 to 30 million people, 30 million people in the month of January with their first dose.

TIRRELL: A key question for you. This comes from Mark C who submitted it via Twitter, and I know you’ve been asked us a lot I know I hear this a lot, but I think a lot of people are still very curious to hear your thoughts on it and I bet you even know what it’s going to be. He asked if I can ask you if you consider sending all the Moderna vaccine out now, with no second dose hold back in light of the 92% first dose efficacy at 14 plus days. He’s notes it’s 225,000 new daily infections indicate as much vaccine as possible needs to be pushed now.

DR. SLAOUI: Right here is, is the challenge with that first of course we’ve been asked the question and first. We, of course spends very significant time modeling, what could happen. And the various consequences. So the first thing to really realize is we don’t have 20 million doses we have 7 million this week at 7 million next week and 5 million the week after, and therefore deciding to give a first to give all the doses produced on an ongoing basis, that’s the key on the rolling ongoing basis. So, to always to new subjects or to new individuals, by definition means by definition means, we omit to give them the second dose. As a decision. I personally have a big problem with that. We have spent seven months explaining to the US population that we have developed these vaccines, according to the best science and the best regulatory requirements possible. What would be the first thing we do, as soon as we have them, is we use them completely in the dark of knowledge of what happens after day 28 or day 21. After one dose, because that’s the reality, we know that we have indeed amazing efficacy between day 14th and day 21 in Pfizer and between day 14 and day 28 with Moderna, but I can’t guarantee you that that efficacy will still be there on day 37, or day 52. And if we knowingly claim and tell people you are immune now, when they aren’t, because we don’t know, they may be but they may not be. I think this would be not responsible. And that could be actually dangerous. This is the number one thing. The second thing is that, because we are using every single vaccine those used. The only way is going to be at some moment, we’re going to have to stop vaccinating anybody and start giving the second dose to those people. Right. And imagine we checked eight weeks of immunization without giving a second dose after week eight week eight. After eight more weeks, we should be not immunizing anybody we should just giving a second dose to everyone that we gave us first those two. So when we did that calculation you realize that you can’t do it that way, that would be really, I think, not responsible, you could imagine to play a week. And if you play week the complexity, the complexity that you create into the system to gain, and we frankly model later ended up saying between one and 2 million people would benefit from vaccination, probably a month or  a half earlier than plan, but you run the risk of a wrongly suggesting to people that it’s okay not to get your second dose, or suggest to people that we break the rules of how you should use the vaccine on day one, or God forbid, if there are manufacturing challenges which we can’t predict. You can put people at a longer risk of, of having an incomplete immune response. So, this is, this is, it’s a difficult decision, but honestly I think it’s, I do think it’s the right decision and what we’re working very hard on is to make sure that the vaccine comes to the rescue, and then hopefully also the AstraZeneca vaccine comes to the rescue as humanely fast as possible to supplement the immunization.

TIRRELL: I know I there’s so much, so much curiosity about those two but I want to ask you, you know, sort of hoping that those will turn out to be effective enough to do to join the supply but right now we know Pfizer and Moderna vaccines work, they’re safe. Moderna should be on the market soon, too, but with Pfizer if you can clarify for us because there’s been conflicting information out there and public statements, you know, Dr. Scott Gottlieb was on CNBC last week, and again on Monday and he said the last offer Pfizer made to the US government to sell its second quarter allotment of doses was in November, you know after the advocacy data, and I know you were asked about this this morning and the operation warp speed briefing and you suggested that you hadn’t seen the efficacy data when the when they offered you the doses, can you just set the record straight for us.

DR. SLAOUI: Yes, I said two things I said first that previous offers is a very big word phone conversation saying we need, we’re going to commit vaccine to other countries. Are you sure you don’t want them happened in August happen in September and frankly, before the first analysis of the data. There is no way we should do it I don’t think it would be responsible to do it because you don’t know. You don’t know which faction you should acquire. After that, timing becomes very important, knowing that, yes, we would like to have another 100 million doses but we want to have them in the second quarter of the year, 2021, and, you know, to be very blunt, we wouldn’t be having all this conversation. If this the real point into the story Meg frankly, is that Pfizer needs, very significant more intense help. Then Pfizer was having because we were helping Pfizer with under conditions that wouldn’t. Create a risk reach of the government into Pfizer. I mean, if we have, for instance to use D pass at the, you know, Defense Act. Production Act Yeah, you know, that comes with consequences to prioritize access to raw material etc. You know, once you know, under normal conditions we did not have an assurance that we will have vaccine doses, in the second quarter of the year 2021. And as I said this morning it’s useless, frankly, to have vaccine doses. In the month of September or in the month of December. So the conversation was there. And what we are observing. And frankly, this would all be normal, discussions, outside of having to have them in the media is to say, we need help. On the one hand and we say yes, and we need vaccine doses so let’s sit together and work this out. We’re going to help you to the maximum and you’re going to make the vaccine those that we need. And that’s how life is. And that’s what’s happening. And as I said, we’re very confident that we will come to a conclusion, that’s a very constructive conclusion and have more vaccines doses for the American people.

TIRRELL: Is it complicated at all by fact that the Moderna vaccine and the Pfizer vaccine are both MRNA vaccines, they’re different, but is there overlap and the supplies that they need and does that complicate your ability to use the defense production act to prioritize materials to one or the other.

DR. SLAOUI: No we don’t. This is the point we never get. And, You know, we lived with five companies, that’s beyond messenger RNA all the vaccine product, use the same things vessels, vials syringes, chemicals, you name it, you know messenger RNA is one element into the equation. Right. And that’s, people need to really realize that and what we have done is really a very thorough job to optimize the portfolio of operational speed, and make sure no company is advantages one way or the other. What happened with Pfizer is Pfizer did not want that kind of help, actively said, No, I don’t want it. Right. And therefore, we couldn’t have them part of that equation, and now they actively want it so that’s very good. I think I don’t think there is an issue.

TIRRELL: You would be using the defense production act to help Pfizer and perhaps we would see a deal struck in the second quarter to deliver doses soon.

DR. SLAOUI: That’s a requirement I mean I don’t think the U.S. government should prioritize manufacturing of vaccine doses for Japan against vaccine doses for the US I think that’s reasonable I think they should. I would agree with that, if the US government is paying for it, and prioritizing it should prioritize the vaccine, the physical doses that will come to the U.S. population first, and then once that is served prioritize the physical doses that go to other people in the world and that’s what we’re doing. I mean, the r&d work, the manufacturing process setup the manufacturing facilities. Those are all things that are there, that would be useful for the globe and world. But I think the expectation of the US people is that we prioritize first immunizing the most people, and therefore we, we need to prioritize first the materials that will go to manufacture vaccines for the USP. I think that’s, I think it’s fair. Now, not a bad thing. If it. If it is limiting Meg sorry let me just made sure I what I’m saying, if a product is limiting, then we would need to prioritize for the US people, if a product is not limiting Of course we would not blindly say Oh, only, we only care about the US people we don’t care about any anybody else, just want to make sure, right. I’m talking about.

TIRRELL: Yeah, Albert Bourla from Pfizer was on Squawk Box with us on Monday morning and he did note that there were some supplies running at critical levels. He didn’t say which ones they were but from what you just mentioned you know the idea of prioritizing the US population over other countries like Japan in order, does that mean in order for the US to help with the defense production act prioritizing materials getting to Pfizer, would it need to break supply agreements it’s already made with other countries.

DR. SLAOUI: No, no, no, I think it’s actually, as I always talk about enhancing capacity and increasing capacity. That’s really what we’re discussing and that’s what the objective is.

TIRRELL: I understand okay I could ask you a million questions on that I want to ask you about the Moderna advisory committee meeting tomorrow and some really surprising data we saw come out in the documents from Moderna about prevention of asymptomatic infection. That seems to suggest this vaccine could prevent transmission. Tell us about the data and how much we can read into that at this point.

DR. SLAOUI: It’s early data, it’s preliminary data. It’s data that we’re taking at day, 28. In the subject immunized, and it has shown a clear imbalance between placebo and vaccine equates to 65% prevention of infection as detected by PCR and people who didn’t have any symptoms so this is clearly asymptomatic infection. I think that data will be very encouraging. Again, it’s short term protection remember it’s just for, you know, up to day 28. In fact, it’s a snapshot. Right. Probably for infections that occurred within a week or 10 days around day 28 and before day 28 and they were carrying over. One area by which – one approach by which we are going to be testing I would say more completely, although it has its limitations – I will tell them in a second – but more completely, the efficacy against infection is, we will be testing in the serum of all subjects vaccinated the presence of antibodies against proteins from the virus that are not in the vaccine. And people who would have gotten infected and were asymptomatic, would normally have an immune response against those proteins. And therefore, we would be able to assess how effective the vaccination has been against prevention of infection. The limitation – I think the data will be very important. And the 65% efficacy for the PCR test is very encouraging in relation to that data. The limitation of the data on prevention of infection as tested by seroconversion to non-vaccine antigen is that already in normal – the natural history of this infection and, quite a percentage of people who are asymptomatically infected, for instance, do not seroconvert, or seroconvert and then the antibodies waning very quickly. And it’s possible that in the face of vaccine, in your response that probably already further decreases the load of virus, maybe a number of asymptomatic infections that have a very small load of virus will not seroconvert to the non-vaccine antigen. I hope it’s clear what I said. So we may overestimate estimate the efficacy against asymptomatic infection. In order to build on this early data of prevention of infection, we are in active discussion of designing a clinical trial, for instance in college students, where students will be vaccinated, you know, they have low risk – high risk of infection, low risk of disease. High risk of transmission. Compare vaccine group to a placebo study that would need to be done quickly and then, for those people who come up on a daily basis with a positive swab see through a contact tracking strategy, whether they have transmitted the virus. Because then we can ask them two questions. A., does the vaccine prevent infection? and B., if it prevents infection or if it lowers the virus load in infected people, does it impact transmission? I hope we can put that study together. It will be an important element for the public health impact of the vaccines.

TIRRELL: Fascinating. I look forward to hearing more about that. I know that you have to go, so I’m going to ask one more viewer question and then one more of my own questions. This viewer question is from Deval Shah, who asks in terms of safety, how would you rank the different kinds of vaccines (RNA versus Adeno Vector)? And I’ll throw in the protein vaccines there as well. And I wonder if you could also just add in your expectation if there will be differences in the efficacy from these vaccines, as well.

DR. SLAOUI: So, if I start with safety first, on the basis of the short to midterm safety profile of the RNA vaccine – 70-80,000 subjects if I combine the Moderna and Pfizer data sets – that data doesn’t look different from a recombinant protein based vaccine. So, you know, really the injection site, and the systemic events associated with demunization itself so they are within 24, 36 hours of immunization. Other than that, there is nothing remarkable. That’s very similar if I take all the population to SHINGRIX vaccine that has – in it and I expected, it’s very similar, for instance, or slightly more higher percentage of pain in the injection site than vaccines using also novel adjuvant, whether they are flu vaccine for instance, or HPV vaccine. The unknown, which is an unknown, but we know that the midterm safety is a predictor of the very long term safety, is a very long term safety, and that we will learn as the pharmacovigilance observations will teach us and show us. And those are going to be super important. I think the – so on that basis, I ran messenger RNA similar and equivalent to the protein vaccine. If I take the life vector of that, it’s very important to know that these viruses are replication defective. And therefore, they actually don’t amplify themselves when they are injected. They are literally like a cargo plane, they deliver the DNA that encodes the protein of the COVID-19 virus to help us get immunized with it. At the doses used, their systemic reactogenicity in the short term – 24, 36 hours – is slightly higher than that of the messenger RNA and of the adjuvant protein vaccine. Slightly more chill, slightly more fever, mostly in the younger age group, same as the RNA vaccine and the same as the protein vaccine. Less in the higher age group. Otherwise, nothing remarkable less pain in the injection site. And then the adjuvant protein vaccine. One of them I know very well – used as part of the GSK and some of the vaccine. Again, a very safe adjuvant in terms of serious adverse events, and an adjuvant that incurs pain at the injection site, redness in duration and chills. Some fever again 24, 36 hours. So, firstly, I would rank the three platforms substantially similarly with the live vectors having slightly less local reaction in injection site, and slightly more systemic reaction. And all of that is within 24 to 36 hours. On the efficacy side of things. I’m impressed with the messenger RNA vaccine efficacy. Really impressed. But that level of impressed was already started at my time on the Moderna board and sharing their R&D committee. It’s really a new platform for vaccines. And it’s very impressive. The level of immune response and used, particularly in the elderly population, and I think a lot of that is actually thanks to the formulation of the messenger RNA, that plays, in a way, an important role in allowing the messenger RNA to get into the cells, and in helping the immune response to be an excellent one. I think I explained the protein vaccines to be very good. The early data from the vaccines are coming out those from Sanofi GSK are less than we hoped for, principally as in the press release, because that those wasn’t we needed to go higher on the dose and higher on purity. Those from Novavax are excellent. And I expect those from Sanofi to be excellent when the right dose gets there. I think the immunogenicity of the AZ vaccine as a two-dose vaccine is excellent. I think it’s so good that we thought this vaccine could go as a one dose vaccine. Because one of the characteristics of this vaccine platform compared to the others is that the immune response continues to go up after the first dose, even if you don’t give a second dose for a much longer period than other vaccines. And that’s one of one of the reasons we decided to take it forward. And I can’t say the same for the ages just because we don’t have that data over time genetically. But it should be similar I think they are at the level that the work done, principally through Oxford University has could have benefited from a more industrial setting. But now, AZ’s providing that and we think phase three trial we’re running here in the U.S. will give us a definitive answer as to the performance of that vaccine. Sorry long answer.

TIRRELL: A lot to cover basically the work you have been doing since May. My last question for you is, you know, a lot of folks say that seeing the people who work on these vaccines receive them will boost confidence. When can we expect to see you get your shot, and which one are you going to get?

DR. SLAOUI: So, I absolutely commit to get the vaccine in public. I’m struggling – any advice people can give me is very welcome. I don’t want to go ahead of the line and be told, you’re taking advantage. And I don’t want to go to the back of the line and be told, you know you don’t believe in it. Frankly, I need help, and somebody tell me –  I mean, I want to do the right thing. My objective is to take this vaccine. But you see my point. And, yeah, I’ll take the vaccine that happens to be coming out, just to show you how much I trust all of them, whatever vaccine happens when I’m told this is the right balance between speed of getting the vaccine and showing that it’s the right vaccine. So when you take it too, I’ll take that vaccine. If it’s a Pfizer, it’s Pfizer. If it’s Moderna, it’s Moderna – I’m 61 so I should get vaccinated, not too long from now.

TIRRELL: We’ll be watching. Dr. Slaoui, we really appreciate your time. Thank you so much for being with us.

DR. SLAOUI: Thank you for having me.

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