mRNA Technology Poised to Change Vaccine Landscape

Ivan Martinez, PhD, associate professor at the West Virginina University Cancer Institute and the West Virginia University School of Medicine in the Department of Microbiology, Immunology, and Cell Biology joined Drug Topics to discuss the latest in mRNA vaccine technology.

Drug Topics®: Good morning, Dr Martinez, thank you so much for joining us. I would love to get things started by having you introduce yourself.

Ivan Martinez, PhD: Thank you, good morning. My name is Ivan Martinez, I'm an associate professor here at West Virginia Univeristy (WVU), as part of the department of microbiology, immunology, and cell biology, but also part of the WVU Cancer Institute.

Drug Topics®: So I'd love to start things off with a high-level explanation of mRNA vaccine technology. What is it and how is it different from other available vaccine tech?

Martinez: Sure, sure. So to start, there is definitely a lot of people thinking that mRNA vaccines are something new. Yes, it's something new that is right now used of course, against the pandemic of COVID-19 but the technology itself is decades in the development. It was in the 1970s when people were already thinking about artificially making RNA, artificially making liposomes that is technically these fat bubbles that are going to cover the RNA and protected it. Of course it was not until many, many decades after that we were actually able to use it. So what technically is an mRNA vaccine? An mRNA vaccine is very different from previous vaccines. You know, most of the vaccines we always use are inactive. Vaccines like polio or rabies that is just dead, well an inactivated virus. They're not dead because they're not an organism that’s alive. So the particles are just inactivated by UV radiation or chemicals, so the virus cannot replicate.

Then there's also the live attenuated vaccines, such as the MMR, so the chickenpox where you let people pass the virus artificially until the virus is very, very mild. It doesn't really give too much of a disease. That's the one they’re used to. Of course, there are other ones like recombinant, toxoids, vaccines and so on. The mRNA vaccine really is nothing else other than the RNA that is actually going to produce a protein of the virus. In this case, SARS-CoV-2, the virus that causes COVID 19 is an RNA virus, that has a 30,000 base genome, pretty big.It’s going to express different proteins for the virus. One of the main proteins that are expressed is the spike. And this spike is, when you see a cartoon or virus images is the little parts that come out of the virus and they're very important. Because that's what the virus uses to recognize the receptors in our cells and attach to go inside. The RNA vaccine actually is an artificial RNA, artificial messenger RNA made in the lab that is going to express only this spike of the virus, not the entire virus, only this spike, because we have expressed this spike that gave us the ability. You develop this RNA, this messenger RNA and you're going to cover it with this, like a bubble, like a fat bubble that is going to protect the RNA, and that's really the nanoparticles that these RNA vaccines are made of. It's the RNA inside of these bubbles. And that's the thing that they injector with. So these bubbles are lipids, if you guys remember your classes, our cells, really the skin of our cells, are also lipids. So what is going to happen is this little bubble of lipid is going to contact our cells and it's going to fuse to our cells. It's going to release whatever is inside the bubble inside of our cells.

The artificial RNA goes inside of our cells. The thing that happened then is inside of our cells, we have this machinery that is sometimes called the translational machinery that is going to recognize messenger RNA and it's going to make a protein. This is happening constantly, all of the time in cells, tons and tons of times per second. And the cells when you put the artificial piece of messenger RNA, the spike of the virus. Our cells doesn't know that it is artificial RNA. So it just sees an RNA and is going to make a protein, thinking ‘oh this is a regular protein, just like any other protein created every single day’. But it turns out this is the spike of the virus and then this spike is going to be presented in the cell surface of our cells. And then this is going give the ability to our immune system to recognize it and say, ‘Hi, this is not ours, so we're going to create an antibody against this.’ And that's how you can create antibodies specifically against a spike of SARS-CoV-2. And that's how you develop this vaccine.

Drug Topics®: So you touched on this a little bit, but mRNA really became I think, a public kind of buzzword after the Pfizer, Moderna COVID vaccines were announced. But beyond these vaccines, there are numerous other mRNA vaccines that are in development across the spectrum for a variety of diseases. Could you touch on some of the potential applications for this technology?

Ivan Martinez, PhD: It is going to be incredible. I'm not exaggerating. And this is why, for many years, for many decades, scientists have been trying to make artificial RNA, messenger RNAs, or making artificial lipids, trying to use them as vehicles to put something inside of our cells. Always like in vitro, always been done in cells growing in the laboratory or maybe in animals, but never in humans until this time of course.But why is it going to be a game changer? Because one of the biggest problems that scientists have for many decades: number one, RNA is very fragile and number two RNA is also immunogenic. Meaning that there's a lot of viruses that infect not only humans, but animals, that their genome is RNA. So for millions of years, we've been evolving this ability to recognize that RNA and attack. Because if our cells suddenly see a piece of RNA just floating around, ‘oh, that's not ours, there's probably a virus’ and they will attack it and destroy it. So that's one of the biggest challenges they have for all these decades: how to develop an RNA that was stable and not immunogenic. That's why they developed these artificial messenger RNAs. Actually they changed some nucleotides to make them more stable and less recognizable to our immune system. That was the big leap in the technology of RNA, artificial RNA.

And then of course, the developing of these bubbles, these lipids, this particle that can cover and protect this RNA.I remember being recently in that meeting with the people from Moderna, and they explained to us how they came up with this technology for developing a COVID-19 vaccine. And it's just incredible. It's incredible, the technology and all of the information they have to have, to get to that point. The idea for them was actually before the pandemic. They were ready to go. Actually they were thinking about influenza first, to develop a messenger RNA vaccine against influenza. They were ready. They were already talking to the CDC and the NIH to try to figure out different ways to start some experiments already, with not only with animals, but also clinical research, and then suddenly SARS-CoV-2 appears. It was like perfect timing for them to have a technology in hand to use it against COVID. But before that they were actually thinking about other viruses.

Now why this is going to be a game changer again, because I am going to give you the second example, influenza, the flu vaccine. One of the problems with that flu vaccine is the flu is a virus that mutates so fast and there are so many different strains of it that the World Health Organization literally has to guesstimate what's going to happen next year. They have to start producing the vaccine for next year, six to eight months before because it takes a long time. They still do it the old fashioned way, infecting chicken eggs with a virus and grow the virus, isolate it, and then mass produce it. That takes months and months and months and months. And every year we'd have different flu strains. So they guesstimate saying ‘well we're going to make a flu vaccine that is going to target two or three influenza viruses for next year’ and hopefully those are the ones that are going to be more prevalent. And sometimes they guess well, and sometimes they can't. Sometimes they completely miss it. And sometimes people get the flu shot and still get the flu. That's one of the problems with this type of technology, old-fashioned technology that takes months and months and months to develop. If you have a messenger RNA vaccine, you can develop it in weeks. So that gives a huge advantage. For example, in the future for researchers and companies to develop something that really is going to be representative of that year's number of influenza strains, that's going to be a game changer for influenza and also for other viruses. And not only viruses, I'm thinking about bacterial infections that can be targeted with messenger RNA, even other diseases. Even cancer, I will not be surprised if people can develop that in the near future.

Drug Topics®: Is there one particular disease state or condition that has proved particularly challenging in terms of mRNA vaccine development? And if so, what have those challenges been?

Martinez: Well, the technology is so new that even Moderna and Pfizer they are still in clinical phase research and sometimes even before preclinical research for some of the virus ,so really we really don't understand yet what diseases will be more challenging than others. Like I just explained, influenza is going to be a challenge because again, we're talking about hundreds of different strains. Coronavirus, SARS-CoV-2 came and hit us hard.Unfortunately for us, we know that there are hundreds, if not 1000s of different coronaviruses in bats, that's most likely where these virus came from. Sooner or later maybe another coronavirus will come out. It’s called spillover. It will spill over to humans and could happen in you know, 5,10,100 years. We don't know. But it could happen. And then again, that will be a little bit challenging. But to be honest, I think this technology is so new that we don't know yet. Sometimes vaccines and sometimes some technologies works beautifully in vitro. It looks awesome and the moment you move to the animal model, that kind of works, and then you have humans it doesn't work at all. There's always this progression that you have to follow.

Drug Topics®: One notable issue with the Pfizer COVID-19 vaccine is the storage, it requires much colder temperatures than usual. Do other potential mRNA vaccines have these temperature maintenance issues? How can these be mitigated for future mRNA vaccines?

Martinez: Yeah, one of the challenges, I tried to explain to people that when computers came out for the first time, they have a lot of glitches and then they said, ‘oh, this is program 2.0 and this is the 3.0.’ So this version for Pfizer and Moderna is like version 1.0. They just started to investigate and start to understand this. There's still a lot of work to do on that. And you're right, one of the biggest challenges is the storage for Pfizer and Moderna. They have to get sort of very, very cold temperatures, sometimes minus 80 degrees Celsius. Because the lipids, it is mostly because of the stability of the lipids, of the nanoparticles. If you get into certain temperature they start getting unstable, and then they expose the RNA. Then the RNA is fragile and can get degraded. So that's the challenge. Actually, two months ago, Pfizer just published a paper that shows and demonstrates that they can leophylize, so they can thrive. The vaccine, the nanoparticles, they are pretty stable even after three months at room temperature and six months at four degrees. So again, that will be a game changer. Because now if you can leophylize the vaccine, the nanoparticles to a powder, you can send it to any place in the world. You just have to resuspend it and then you’re ready to go.

Drug Topics®: I just want to talk about the storage again. Why is the appropriate storage of vaccine components both during the R&D phase and then after the vaccine is completed, critical for patient safety?

Martinez: More than the patient safety, I think it's about the effectiveness of the vaccine. I don't think the problem is that something's going to happen to the patient. I think it's mostly that the vaccine is not going to be a very good vaccine if it doesn't get stored at that temperature. Because imagine you have 1000 nano particles of the messenger RNA in a vaccine and you put it in room temperature and then they become unstable and start opening, then the RNA starts getting degraded. Instead of putting 1000 particles to a patient, you only put 100.How much will that affect the vaccine efficacy to develop antibodies against a virus? I think that's the biggest challenge. I don't think it is much about a problem with the patient or having issues with being toxic or anything like that.

Drug Topics®: Can you talk about the RNA and mRNA research that you and your team have been undertaking and what advances you hope that this research will make in terms of mRNA vaccines?

Martinez: Sure, we have several researchers here in the lab. My lab is really an RNA lab, but also a virology lab. We are focusing mostly on noncoding RNAs. I'm going to explain a little bit what noncoding RNAs means. I love it, because it's kind of like dark matter in biology. Dark matter in astronomy, we know is there, but we don't know what it does. It’s the same thing for noncoding RNAs. Let me explain it to you in simple terms: Imagine that you have a bacteria.The genome of bacteria normally gets transcribed, meaning it is going to make RNA. Most of these genomes are going to make RNA, like 98% of the genome is transcribed to RNA. All of these RNAs are translated to proteins. 95% is translated for this purpose, very efficient, very simple organisms bacteria. How much of that is happening, for example, in an insect? Imagine the genome of a grasshopper. Most of their genome is also transcribing RNA, like 95%. And that RNA, how much is being translated to proteins? That's the final product of information. And it turns out, it's only 70% of the genome of an insect that is translated to protein. Then you have the same question for humans. How much of our genome is transcribed to RNA? We're still talking about a little bit more than 90% of our genome is transcribed to RNA. How much of that RNA is translated to protein? Only 2%. So that means that we have a universe of RNA inside of ourselves that doesn't code for a protein, doesn't make proteins. We always believed RNA was more like a messenger, that's why it's called messenger RNA. We thought that it’s just a messenger that takes information from our DNA, our genome to make proteins and yes, messenger RNA does this job, but messenger RNA is a very small percentage of the universe of RNA that we have in ourselves. So these other RNA that don't have that message to make a protein are called noncoding RNAs. These noncoding RNA, there are hundreds of 1000s of them. Most of them, we have no idea what they are.

That's my laboratory, we try to understand their function. In the last 20 years, there have been amazing discoveries, because now we know that a lot of these RNA are involved in viral infections, in cancer, in almost any human disease that you can think of. Diabetes, Alzheimer, there are actually noncoding RNA involved in these diseases. We just started to understand what is their role? What is their function?I'm going to give a quick example. In our laboratory, we discovered long noncoding RNA. It's called long noncoding because it's bigger than 200 bases. Any RNA that is bigger than 200 bases and doesn’t code for a protein is called a long noncoding RNA. These long noncoding RNA that we discovered gives sensitivity to radiation for lung cancer. Cells that have this RNA are more sensitive to radiotherapy in lung cancer cells. The interesting thing is this long noncoding RNA is only present in males. Why? Because it comes from the Y chromosome. We have no idea how different it is in females. One of the things we're discovering right now in the lab is that these long noncoding RNA and these tumors these male tumors, lung male tumors, some of them are resistant to radiation. They lost their Y chromosome. They don't have a Y chromosome anymore, even though they came from male patients. We're trying to understand how these long noncoding RNA are helping the cells to become more sensitive to radiation therapy.

In the future, of course, we want to hopefully create an RNA vaccine that we can include noncoding RNAs inside of the lipid. Give it to a patient that has resistant lung cancer. Give it to them and make them more sensitive to radiation therapy. So that will be a strategy for that. Now the other one that we have is for SARS-CoV-2. We are growing the virus artificially, in a very specialized laboratory, the biosafety level three facility that we have here at WVU. We're the only lab growing the virus there. We're actually infecting human lung cells in vitro. We're discovering that the virus is changing the expression of the messenger RNA in our cells and specifically some messenger RNA that are important as an antiviral mechanism, that is independent of our immune system. So the virus, it evolves. It’s very smart, in that sense that they want to avoid the immune system outside the cell, when they're outside the cell or in the moment they’re going inside the cell. They also want to avoid the immune system. How to avoid it? You change the expression of messenger RNA inside the cell so they don't expose the proteins that are against you as a virus. That's the thing we're trying to understand the importance of these RNAs.

Drug Topics®: As we wrap things up, are there any other key points or final takeaways that we haven't covered that you'd like to discuss today?

Martinez: Hopefully people understand that this is like the time where RNA is going to give them much more in not only vaccines, but in other types of research. As RNA researchers we will be waiting for this time. For a long time, people really didn't believe too much in RNA. They mostly believed in things that are based on proteins and another type of old-fashioned vaccines, but now that the RNA vaccines are out and now we understand better some of the mechanisms, I can see that this type of research and this type of technology could change dramatically how we are going to do research against certain diseases, but also how are we going to treat people with this type of technology that has so much potential.

Drug Topics®:Thank you so much again, Dr. Martinez for joining us. This was incredible. I feel like I learned so much. I think our audience will also take a lot away from it.