Welcome to another COVID-19 update, and we're gonna be talking about the AstraZeneca vaccine in this update. Daily new cases in the United States are atan all time high, but it may be peaking. We don't know, need to get some more data here. But if you look at the data you can see that there has been some what of a slowdown in the number of cases. Of course with deaths, they lag behind, may be a couple to three weeks, and the daily new deaths are increasing as well at this point. Again, we're gonna have to wait for further data.
Now we're gonna talk about the AstraZeneca-Oxfordvaccine, and we're gonna compare to the ones that have gone before it, like the Pfizer-BioNTech vaccine, and the Moderna vaccine. Now, as you will recall, the Pfizer-Biontech vaccine and the Moderna vaccine are basically new vaccines in the sense that they are injecting messenger RNA into your cells to tell the cells to produce the protein that is the same as a portion of the spike protein that is on the virus, and that is what generates the immune response. So in other words, we're giving instructionsto the cell to make the form protein, which causes the immune response and that is actually very similar to the AstraZeneca-Oxford vaccine, except, instead of using messenger RNA, they're using DNA to do that.
So once again, in terms of a picture, imagine we have the cell and we've got the nucleus. And what we were doing before, was we were taking messenger RNA and that messenger RNA was being translated by ribo somes and converted into the protein. What we did with the Pfizer-Biontech vaccine and the Moderna vaccine, is we were getting the messenger RNA into the cytoplasm of the cell. The cytoplasm is the outside portion, as opposed to the nucleus. How do we get that messenger RNA in the Pfizer-Biontech vaccine and the Moderna vaccine in? Well we used a lipid bilayer, or a micelle as we called it, to get those fragments, or the messenger RNA, into the cytoplasm. And then from there, it's fairly straight forward.
The cell uses its own cell machinery, which is the ribosomes, to cause translation to occur and you make the protein in question. How this is different is AstraZeneca uses a different technique. And it uses a virus called an adenovirus, but not a human one, but a chimpanzee. Now why would it do that? Chimpanzee adenoviruses have not really been exposed to the human population, so it's very unlikely that humans would create an immune response against the adenovirus specifically itself.
We don't want that to happen. Because if that happens, then the vaccine is not going to be effective at getting its instructions into the cell. Of course, AstraZeneca knows that if this vaccine is successful and is used on a number of people -- millions, billions of people worldwide -- then it's probably going to have to abandon the chimpanzee adenovirus platform for delivering instructions.
Now, the adenovirus here does not use RNA, like we've been talking about. It uses DNA, and DNA is a double-stranded form of instructions. Now, there's a portion there in the middle of that, that is used for replication of the virus. Well, the genetic engineers simply delete that portion, so the virus can no longer replicate and cause an infection in the human body, and instead they replace that portion of the DNA with genetic code (the instructions) that the geneticists have engineered. And so what happens when you deliver this adenovirus in the vaccine, it goes into the cell and it releases the DNA into the cytoplasm, and then that gets taken up and goes into the nucleus.
That DNA -- according to scientists at AstraZeneca-- does not get incorporated into the host's genome. It does not go into your DNA in the cell, but rather it is transcribed into RNA, and that RNA then exits the nucleus as a messenger RNA and then exactly the same thing happens as what we saw with the Pfizer-Biontech vaccine. The Moderna vaccine, which is that the messenger RNA, which is now a product of the transcription of the DNA, gets converted into the spike protein through translation by the ribosomes and then this goes on once again to cause the immunogenic response.
Now there's a couple of points that you should underst and about the trial, the AstraZeneca and Oxford trial, that's been looking at this vaccine. Let me just stress to you that the results that we have gotten here in the last few days are via press releases and not peer-review edarticles that have been published and reviewed. So the first differences we talked about is that it is a DNA virus platform, and there's been many areas that they've been doing research and predominantly, let's take a look at two of those areas. The first one was in Brazil, and the second are a that they did the trials was in the UK. Be also aware, though, that they are doing trials in the United States as well.
From the numbers -- and I'm rounding these off -- there's been about 9,000 people that have been enrolled in Brazil, and about 3,000 that were enrolled in the UK. Now, just like the other two vaccines that we were talking about, this is also a two-step process. So, there's two injections, or two vaccinations, and they're about a month apart. Now by some error that occurred in the UK trial, they gave half a dose first, followed by a full dose. Now, in the Brazil trial, they gave a full dose, like they were supposed to, followed by a full dose, and this happened approximately 28 days apart. Now, if you've listened to us when we talked about the other two vaccines, you'll know that in those other two vaccines they did the trial a little differently in terms of the fact that they waited for subjects to become symptomatic with COVID-19 symptoms.
Before looking at the end point there, ora midway point, to see whether or not the vaccine was effective. Here in the AstraZeneca case, they were not doing it that way. No, in fact they were doing swabbing and they were checking for infections. This is a huge deal, because where as with the Pfizer-BioNTech vaccine candidate and also the Moderna vaccine, all we can really say about those two -- even now with the results that we have -- is that it is definitely effective if what they're saying is true at preventing the symptoms of COVID-19, at preventing the disease, at preventing the things that cause people to go to the hospital.
What we don't know right now about those two vaccines is whether or not the vaccine prevents infections. That's important because infections leads to transmission and transmission leads to spread of the virus. Now here with the AstraZeneca-Oxford study, they actually checked for infections by doing nasal swabs, and so what we can say here is that whether or not there has been a stoppage or a ceasing of transmission and thereforeinfections.
Now what was really interesting and kind of a headscratcher is in the Brazilian portion of this study, where they gave the full dose on the first injection and the full dose on the second injection, the efficacy was only about 62 percent. Now I say "only" because we're comparing it to what we know now about the other two vaccines, but 62 percent is not a bad result. And it certainly meets the bench mark, or the threshold, for getting emergency-use authorization from the FDA both here in the United States and also in Europe.
However, the part that's kind of a headscratcheris that when they, by some serendipitous error, they injected the subjects in the UK with half a dose on the first shot and then a full dose on the second shot, this one was actually 90 percent effective, and that's not just for preventing COVID-19, as I said. That may also, according to the preliminary results, prevent infections from what they're telling us.
So the US trial was paused because there were some events in two subjects in the United Kingdom, and one subject in Brazil, that was deemed later not to be related to the vaccine, but it took them time to investigate. They have restarted the USA portion of the trial, but now they want to see if they can, in midstream, modify that to introduce some half-dosing as well, combined with perhaps full-dosing to see whether or not they're going to get a similar result, either 62 or 90 percent or something in between.
Now the other thing that was very interesting about this is that obviously some people are getting placebos, but in not every situation are those placebos just saline or salt water. In fact, in the first injection, what they have been doing is getting a meningitis vaccine dose, because they wanted to reproduce the symptoms that people got, when they got an injection. Because when you get an injection with saline, it doesn't cause irritation at the site as much, it doesn't cause pain at the site as much, but a regular vaccine that would have nothing to do with coronavirus, such as ameningitis vaccine, might do that.
So , AstraZeneca-Oxford trial is a little different than the other two in that they were giving other vaccines as placebo. The reason that they're doing this is to get a more realistic placebo effect so that the subjects can't tell whether or not they've gotten the vaccine, in this case, or whether they're in the placebo arm. So what are the other possible advantages? Well, with the Moderna vaccine, as we talked about, it had to be stored, if you wanted to store it for 30 days, at negative 20 degrees centigrade or negative 4 Fahrenheit, and as you recall from the Pfizer vaccine, it was even more extreme. It was at negative 70 degrees Centrigrade or negative 94 degrees Fahrenheit to store it for six months.
Here, just a regular refrigerator is all that is necessary. In fact, it only needs to be stored at 2 to 8 degrees Centrigrade or 36 to 46 degrees Fahrenheit. So those are some advantages there. And of course because of that you don't need to build an infrastructure system, you just need regular refrigeration to store this vaccine.
The other thing that's very interesting as well, is that AstraZeneca has promised not to make any profit during the pandemic on this vaccine. So while the cost of giving the other two vaccines is around the $20 range, the AstraZeneca-Oxford vaccine is going to be sold for anywhere between $3-5. And not only that, the AstraZeneca-Oxford vaccine is potentially going to hit about 3 billion doses. What's interesting is that because they only needed a half dose for the 90 percent efficacy, they would actually be able to save some of that material and that could immediately go as high as 4.5 billion doses worldwide.
The other thing thats interesting politically as well is that because the United Kingdom is leaving the EU, they would be able to get this fast-tracked within their own country without depending on EU approval. However they are applying for EU approval as well. Other things that came out in the press release is that there were no serious side effects. The other thing that said too was that there were not severe COVID cases in those patients that got the vaccine. So let's review: how is the AstraZeneca-Oxford vaccine similar to the Pfizer-Biontech and the Moderna vaccine. Well, it's similar in that two vaccinations are necessary, approximately one month apart.
It's also similar in that it delivers the instructions to the cell, for the cell itself to make the protein antigen that stimulates the body to make the immune response. But this candidate is different in the fact that it's a DNA virus. It's also different in that it doesn't really require subzero temperatures to preserve it. It's also different in terms of the fact that it's going to be a lot more affordable, especially for countries that don't have the infrastructure to keep these vaccines at very low temperatures.
It's also different that there is this headscratcher type of situation here, where we don't really understand why this small UK group had such high efficacy especially with only half the dose on the first dose. So right now we're kind of feeling around in the dark. What we really need to have and what we are going to have very shortly is the actual data released that will be peer-reviewed and published. If you like this information, follow follow for more contents like this. Thanks for joining us.
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