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The Dose Transcript for May 10, 2023

Host: Dr. Brian Goldman

STORIES FROM THIS EPISODE

BRIAN GOLDMAN: Hi, I'm Dr. Brian Goldman. Welcome to The Dose. Remember last fall and winter when adults and especially infants and young kids filled ICUs? And which led to er waits of 18 hours or more. The cause was the so-called triple-demic of viruses, two of them COVID and influenza, had vaccines. The third virus, respiratory syncytial virus, or RSV, did not. Well, we have an update. Last week, the U.S. Food and Drug Administration approved the first ever vaccine for RSV. So today we're asking, what do I need to know about this new RSV vaccine? Hi, Sabina. Welcome back to The Dose.

SABINA VOHRA-MILLER: Hi, Brian. Thanks for having.

BRIAN GOLDMAN: Me. So what was your reaction when you heard this vaccine was approved?

SABINA VOHRA-MILLER: I was frankly very thrilled to hear this. It's a long time in the making. And I think, you know, having another one of these vaccines in our arsenal, especially as we head into another, you know, flu fall, flu and influenza season, I think it's fantastic to have.

BRIAN GOLDMAN: Yeah, I think it is fantastic. And the thing I thought of, boy, it would have been nice to have it as the triple the triple-demic or even before the triple-demic was was unfolding. But, you know, we're we're here to hear about the fact the vaccine and everything that you know about it. But before we begin, can you give us a hi, my name is tell us what you do and where you do it. Just ad lib.

SABINA VOHRA-MILLER: Absolutely. My name is Sabina Vohra-Miller. I'm the founder of Unambiguous scientists at science based platform, where I really try and increase science literacy for the general population. I am and I also have a master's in clinical pharmacology, and I'm currently a doctor of public health student at the Dalla Lana School of Public Health at the University of Toronto.

BRIAN GOLDMAN: Okay, here we go. First off, what do we know about RSV as as a viral infection?

SABINA VOHRA-MILLER: Jan You know, RSV actually has been making the rounds lately quite a bit. I mean, as you mentioned, you know, last year, last fall, we had a really brutal fall with the triple-demic. In fact, there were some estimates that were suggesting that almost 40% of households had, you know, were experiencing this triple-demic of influenza, COVID and RSV. But, you know, RSV is not a new virus. It's been around from the very beginning, and it's a highly, highly contagious virus that causes infections of the lungs and the breathing passages. And the circulation is, you know, very similar to that what we see with influenza. So it's seasonal starts typically in the fall and, you know, peaks in the winter. Now, for most people, RSV causes very minor cold like symptoms, you know, usually just upper respiratory tract type illness. And people recover usually typically within a few days, but in younger people and older people and then some immunocompromised people, it can actually cause lower respiratory tract infections. And you know, with that, too, what it causes is something known as bronchiolitis, which is the inflammation of the small airways in the lung. I can also end up causing life threatening pneumonia and in some cases death as well. And so it can be quite severe in certain populations.

BRIAN GOLDMAN: And you know, Sabina, when it comes to older adults, frankly, I was surprised that a fair number of older adults had to be admitted with RSV during the fall and winter.

SABINA VOHRA-MILLER: Absolutely. I mean, if you look at the statistics, you know, per the CDC every single year, RSV results in between 60 to 120000 positions and 6000 to 10000 deaths among adults who are 65 years of age and older. So it's absolutely nothing to sneeze at. And the fact that we be, you know, trying to work on a vaccine specifically in this population for a very long time is really telling because there is such a severe burden of disease in the elderly.

BRIAN GOLDMAN: So that's RSV. What do we know about the new vaccine?

SABINA VOHRA-MILLER: Yeah, so the new vaccine was just approved by the FDA. It's actually the first RSV vaccine that's ever been approved. So this is huge news. And this this one actually is called our vaccine. It's by GSK, and it was approved for individuals who are 60 years of age and older. So this vaccine is a protein subunit vaccine. So it's actually very similar to other vaccines in terms of the technology. You know, for instance, the hepatitis B vaccine is also a protein subunit. And more recently, you know, many people are familiar with Novavax. That is also a protein subunit vaccine. And you know, what was amazing about this is because of that massive burden of disease, this vaccine received priority review with the FDA and the European Medicines Agency, the EMA as well, and it was just recently approved by the FDA.

BRIAN GOLDMAN: What kinds of side effects were seen in the clinical trial?

SABINA VOHRA-MILLER: Yeah. And so, you know, first of all, I want to mention the clinical trial was absolutely incredible in terms of how robust it was. So it's an ongoing randomized placebo controlled phase three trial and in fact included 25,000. Participants said, you know, as you know, in recruiting, these many participants in a clinical trial can get very tricky and it's very difficult to do. But they were, in fact, successful to recruit these many people in the study. And what they found with one dose of this vaccine, it significantly reduced the risk of developing any RSV associated lower respiratory tract disease by 82% and severe disease, in fact, by 94%. So extremely efficacious and efficacious for both, you know, RSV a as well as RSV and B subtypes. Now, in terms of adverse events, you know, what we saw were actually what we would typically see with any vaccine. So we saw things like injection site reactions like pain, some fatigue, some muscle pain, some joint stiffness and pain and some headache. But the good part is that the incidence of any serious adverse events were in fact similar between the vaccine group and the control group. So, you know, I think especially given the fact that ve been researching RSV vaccines for so long to find something that is efficacious and safe has culminated in this vaccine that had extraordinary efficacy and was also very, very well tolerated.

BRIAN GOLDMAN: So if if this works as well as we think it will in the general population as it did in the people who were studied in this large clinical trial, this vaccine could prevent a large number of deaths, couldn't it?

SABINA VOHRA-MILLER: Absolutely. Especially given the remarkable efficacy against severe disease. You know, I think that is one of the parameters that is so and, you know, critical to look at. And a reduction of 94% is is fantastic.

BRIAN GOLDMAN: So we've been talking a lot about older adults. But I want to ask you to remind us why it is that infants with RSV tend to get much sicker in general than than, say, you know, young adults or middle aged adults.

SABINA VOHRA-MILLER: Yes. Of the other population that is, again, very susceptible to RSV are infants. And this is because they have smaller lungs. Their their passages are much narrower as well, and their lungs are not fully developed. And so they tend to have a lot more of the lower respiratory tract illness that we see with severe infections. And so if you look at children under age five, it actually results in around 58,000 to 80,000 hospitalizations and, you know, up to 300 deaths annually. And it's actually the number one cause of hospitalizations for children under the age of one and the second leading cause of death in children under age one globally. So there is, again, another huge burden of illness in this population as well. And you know, the other thing about RSV infections in infants is that it's unpredictable. So all infants have this potential of developing a severe RSV infection. And in fact, most hospitalizations for RSV occur in completely healthy infants born that term. And then on top of that, you know, it also puts children at risk for developing other downstream issues, you know, such as, for instance, asthma. We have data to show that kids who get very sick with RSV in their first year of life end up having 2 to 4 fold higher risk of developing asthma later down in their life. So, again, it you know, it is that it does cause significant illness even in children who are under the egis of one.

BRIAN GOLDMAN: Now, the vaccine that you and I have been talking about will not be given to infants, but I gather that there are other vaccines in development or at least one other vaccine in development that could be given to pregnant women and that could have a positive benefit on their children once they're born.

SABINA VOHRA-MILLER: Absolutely. And so Pfizer you know, Pfizer actually has this vaccine in place, not just for the elderly population over age 60, but also this vaccine would be administered to pregnant people to see whether, you know, they can actually provide some of that protection to infants when they're born. So this is actually through transplant until a transfer of IGG antibodies. We call it passive immunity. And so what it does is it actually passes immunity from the pregnant person to the baby, and it lasts for the first few months in their lives. And, you know, the Pfizer vaccine, in fact, has just read out some of their data. It, again, looks very promising. And they have applied for FDA approval in February and they applied to Health Canada in April of this year. So we should, you know, see this vaccine available at least, you know, for use in maternal during pregnancy for infants who are under age six months, hopefully, in fact, by the end of this year.

BRIAN GOLDMAN: So if you if one were going to vaccinate a pregnant woman in order to protect her children, provide passive immunization to to the child through the placenta for, say, up to the first six months of of the infant's life. When would you have to deliver that vaccine to the pregnant woman?

SABINA VOHRA-MILLER: So the most ideal timing of actually delivering a vaccine for, you know, at the most efficacious transfer of IGG antibodies typically is in the early third trimester of pregnancy. So, you know, between 27 weeks to 32 weeks is ideally the time when you see the most transfer of antibodies. And, you know, and I think the reason why you want to actually have this vaccine given to pregnant people is that young babies do not really have a a robust immune system is not mature enough to actually make protective antibodies themselves in response to a vaccine. So for, you know, infants who are under age six months, who are at one of the highest risks for RSV, severe illness, the best way to, in fact, protect them is not necessarily by giving them the vaccines themselves, but in fact giving the vaccine to the pregnant person during pregnancy at that ideal time to allow for maximum transfer.

BRIAN GOLDMAN: But at some point, clearly, even with this kind of a strategy, an infant is going to run out of passive immunization courtesy of mum. So are there any vaccines in development that are aimed at infants, given the fact that there are lots of infant vaccines?

SABINA VOHRA-MILLER: Absolutely. So unfortunately, as of right now, none of the none of the vaccines that we have in development have started any of the pediatric trials. So what I mean by pediatric trials is actually giving the vaccine directly to the infants. So those studies have not started. I am hopeful that, you know, a lot of trials typically in the pediatric population is very much phased in as stepwise, where you want to make sure the first step is safe. You move on to the next step. And so, you know, I do think in the next few years we will have more vaccine candidates that can be given directly to infants. By this time, we don't have that. However, what we do have and again, this is something that is exceptionally exciting are monoclonal antibodies. And so this is actually just providing some of that immunity directly to infants. And so Sanofi and AstraZeneca, in fact, have developed a new monoclonal antibody it's called before it is. And this it's administered as a single dose to infants and newborns before their first RSV season to protect them for that RSV season. And this was actually already approved by the European Commission. And a couple of months ago when it was approved in Canada, end of April as well, and expected to get FDA approval by August of this year. And the most impressive part about this monoclonal antibody is that it's long acting. So up until now, we did have another monoclonal antibody called synigis that was given to specifically infants who were at very high risk of a premature. And it has to be given on a monthly basis. So it would be basically given every month for five months for the first RSV season. And where is this new monoclonal antibody just has to be given once per season and it protects you throughout. And because of that, you know, the efficacy is fantastic for for this new vaccine and because it's long acting. The CDC's ACIP committee that basically recommends use our vaccines have said that so far they would recommend this antibody for all infants. So not just premature and not just high risk children, but all infants for their first RSV season.

BRIAN GOLDMAN: All infants as opposed to infants at particularly high risk.

SABINA VOHRA-MILLER: Exactly. Now, hopefully, you know, we have similar recommendations here by NACI, but that's yet to be seen.

BRIAN GOLDMAN: So remind me, is this treatment approved in Canada, this new monoclonal antibody treatment? Is it something that that infants are going to lightly likely be able to to receive as a treatment anytime soon?

SABINA VOHRA-MILLER: So it was just approved less than two weeks ago. So very, very new. But yes, we do have approval for it. We're still waiting to hear Nancy's recommendations on who is. And we still have to understand what the manufacturing and supply looks like. But I am exceptionally hopeful that we're going to have this in our arsenal come fall 2023 as we head into the next, you know, influenza season.

BRIAN GOLDMAN: Wow. That's that's that's amazing news. Thank you for sharing that. How long? I want to get back to the to the vaccine that was approved by the Food and Drug Administration in the U.S. How long were vaccine researchers working on that particular vaccine?

SABINA VOHRA-MILLER: Oh, wow. What a great question. So, you know, this is the first RSV vaccine to be approved, but it has not been for lack of trying, let me tell you that. And we've just been very, very unsuccessful up until this point. In fact, we started trialing, you know, our designing and RSV vaccine back in the 1960s, you know, where we had this inactivated RSV vaccine for young children. And unfortunately, it completely backfired, you know, instead of preventing infections, ah, illnesses, in fact, it ended up causing more enhanced form of RSV, some more severe form of RSV in the infants who received the vaccine. And we, you know, immediately stopped that trial. And the last 50 years have been spent in terms of understanding what caused that. How did you know the vaccine failed so spectacularly and how to prevent it, how to actually get us to a point where we have a safe and efficacious vaccine. So it's been in development since the 1960s. You know, have you been doing that clinical research to try and make sure we get that really good data, really good due diligence until we have a vaccine that can be finally approved, which is, you know, we're finally there.

BRIAN GOLDMAN: And here we are with an explosion in new vaccines. Why do you think vaccine development is more successful today compared to years ago?

SABINA VOHRA-MILLER: You know, I think that there's a lot to be said about learning from previous mistakes, and I think that has actually been pivotal for us. You know, if you're looking at even the RSV vaccine, you know, for example, or the hypothesis that we have as to why the first vaccine failed is because we actually think the vaccines were not eliciting a really strong immune response. And so the antibodies were not binding strongly enough to the inactivated virus to produce a, you know, a really good protective immune response. Instead, the antibodies were sort of dragging the dengue virus with them wherever they went, and that ended up triggering this massive attack by the entire immune system, causing essentially things we didn't want to see. And so I think that, you know, the failure of that vaccine, in fact, really helped us understand what we need to need to be seeing when we're developing an effective vaccine. And in fact, we also have new technologies. You know, I mean, we talked a lot about the protein subunit vaccine, but Moderna is actually also in phase three trials looking at an RSV vaccine using their marinade technology. And again, we've had so many years in the last. I would say decade or two, where we been looking at many vaccines, understanding how we can use this technology. So we've come a long, long way. And I'm actually, frankly, very excited about what we're going to see in the future.

BRIAN GOLDMAN: So the new monoclonal antibody treatment has already been approved by Health Canada. I gather that the Pfizer vaccine, which would be given to pregnant women, that Pfizer has made application to Health Canada just as they've made application to the Food and Drug Administration for approval. What about the vaccine by GSK, the one that the FDA approved last week have? Has the company made application to Health Canada? When will we see that one here?

SABINA VOHRA-MILLER: Yeah. So they in fact, also applied to Health Canada last year in December. So December 2022 was when they applied for Health Canada approval. So I don't know if they actually received priority review, but my assumption is that they likely qualified for Health Canada priority review as well. And if so, we should actually see something from Health Canada by the end of the summer for the GSK vaccine in the 60 plus population as well. I'm keeping my fingers crossed. Hard for that.

BRIAN GOLDMAN: As as are all of us. Last question I'm going to ask you, given the fact that RSV, you know, most of the time it causes a mild illness but can cause severe illness. What are some of the symptoms that should trigger seeking medical attention, whether you're the parent of an infant or whether you're an older adult who is developing a more severe form of the infection.

SABINA VOHRA-MILLER: Yeah, You know, I think one of the first things we see, especially in infants, is actually, you know, with them struggling to to get a nice deep breath. And so, you know, personally, my son had RSV at ten weeks and our first indication was that he was in fact having these chest retractions that were quite severe. And you could see that he was really struggling to take that deep breath in. And so that was our first indication to take it to the emergency room and actually see what was happening. And we've been in adults as well. You see that where you can see that it's getting it makes it very hard for them to actually get that good deep breath in. They can have really sharp chest pain. They can be out of breath. You know, they can wheeze as well. So all of those symptoms and adults shows that you're really struggling to get that that good breath in. You can also have cough, shortness of breath. And, you know, I think fever is less common in adults, but it can occur. But fever was another symptom that we saw in our infant as well when when he had RSV. So, you know, I think one of the biggest indicators would be just to to see how hard someone is is working to get that deep breath in.

BRIAN GOLDMAN: And with new vaccine development, we see fewer and fewer infants and older children getting those symptoms and needing hospitalization. That would be a really good thing. Sabina Bora Miller, thank you so much for speaking with us.

SABINA VOHRA-MILLER: Thank you so much for having me. I really appreciate it.

BRIAN GOLDMAN: Sabina Vohra-Miller has a master of pharmacology and is a student in the Doctor of Public Health Program at the University of Toronto. She's a founder of the website Unambiguous Science. Here's your dose of smart advice. RSV is a common virus that usually causes mild, cold like symptoms, but the virus can also produce serious illness in infants and older adults. It's the number one cause of hospitalizations for infants under one year of age. A new vaccine by GlaxoSmithKline called a Rex feed recently got FDA approval. It is indicated for adults 60 years of age and older in a clinical trial. The vaccine reduced the risk of infection by 82% and reduced the risk of severe illness by 94%. Side effects of the vaccine include soreness at the injection site, muscle and joint aches and headaches. The vaccine has been submitted for approval to Health Canada. Another vaccine made by Pfizer that would be indicated for adults age 60 and older and pregnant women is under review by the FDA and by Health Canada. In addition, Health Canada just approved a new antibody drug to help protect babies up to age two from serious illness caused by RSV. Fortunately, most people have mild symptoms. For them, the treatment includes acetaminophen and ibuprofen to manage pain and fever as well as fluids. Seek emergency care for infants under six months of age and older adults who are having trouble breathing or who are dehydrated. If you have topics you'd like discussed or questions answered, our email address is the dose at cbc.ca. If you like this episode, please give us a rating and review wherever you listen. This edition of The Dose was produced by. Isobel Gallant, our senior producer is Colleen Ross. The Dose wants you to be better informed about your health. If you're looking for medical advice, see your health care provider. I'm Dr. Brian Goldman. Until your next dose.

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What do I need to know about the new RSV vaccine?- Transcript

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