The amazing thing about science writing is that it's never static. What you read one day might be totally different the next, and this final chapter of the COVID trilogy is accompanied by news that completely, pleasantly, contradicted my understanding of our progress towards a vaccine.
To start this post, we've talked about the dangers of SARS-CoV-2 as a novel virus, and we've talked about how now at least we have the ability to detect the virus in humans. So now, for the final boss- how do we beat this thing? Sadly this answer is not as simple as the other ones have been, because there is lots of science, but much less conclusive science in this realm so far.
Why is that? Why could we figure out what this virus is about, and how to test for it, all in the course of a few months but we can't figure out a way to treat it equally as fast?
For starters- no one (or very few people) wants to sign up to be the first person to receive an experimental treatment or vaccine. People don't exactly jump at the idea that they might try something, and it could work, but it also could have major adverse side effects that scientists haven't discovered yet. Or, even worse, science might show that there are no adverse side effects- and then that first trial patient might be the "special case" that experiences something completely unpredictable.
Scenarios like this go on and on, but luckily, there are a lot of scientific practices that prevent this from happening (or, at least, they do their best). There are several rounds of preclinical trials and testing that take place, often on animal subjects, that allow scientists to figure out what the best and worst types of treatments will be for people with different pre-existing conditions, genetic predispositions to things, and even people in different age groups.
Once you move past the animal-testing-phase, you enter clinical trials, which is a four- to five-phase process that allows scientists to start slowly testing the efficacy of their drug on human patients. Depending on what the drug specifically treats, the length and difficulty of these studies can vary quite a bit, but overall it's a set of tests designed to keep the public safe while also moving medicine along as out scientific knowledge progresses.
So it's a good thing- we have a system of tests in place that makes sure that not only are the drugs we receive effective, but are also very safe for the vast majority of the human population to use. We also already know what the potential side effects of drugs are, and the proper dosage depending on our age or pre-existing conditions.
This is excellent news, with a small caveat... getting a drug from research to market takes a VERY long time, and in the process of approval from the FDA, a lot of drugs face rejection. In the US, it takes an average of 12 years for a new drug to get from a scientists benchtop to the hands of patients. The odds of a drug even making it that far are also pretty slim- out of every 5,000 drugs submitted for approval, only five make it to human testing, and of those five only one will actually make it to market.
That's a long time, and pretty poor odds, for a drug to get approved. So when it comes to COVID-19 therapeutics how are we ever going to find a treatment to this without waiting 15 years for the approval process to finish up?
Luckily, the FDA can use a special "bypass" for some of the longest part of this process- it's called issuing an EUA. EUA stands for emergency use authorization, which was put in place specifically for states of medical emergency... such as a pandemic.
It was because the FDA issued an EUA that just earlier this month, a monoclonal antibody treatment was approved in the US for patients at high risk, such as those over the age of 65 or with predispositions to experience the most severe symptoms of COVID-19. This treatment uses what are called mAb, or monoclonal antibodies, to help patients' immune systems fight off an established SARS-CoV-19 infection. This treatment is mostly reserved for patients who are already hospitalized and require breathing assistance at this point, and if I had to guess, that's probably the way it will stay for the time being.
While mAbs are a great therapeutic for established infections that require targeted attention, they're not a sustainable solution for people with ongoing symptoms or as a preventative measure. Usually, our bodies produce antibodies as a response to an invading pathogen, and then continues to produce them until the invader is defeated. In the case of mAb treatment, however, you get a single dose (or a series of a few doses) of antibodies, and then no more. This doesn't teach your body to create the antibodies for itself, necessarily, so you're not armed for another invasion from the same pathogen.
Plus, producing monoclonal antibodies involves a lot of precise biological engineering and use of laboratory animals, which overall adds up to a pretty expensive treatment.
Luckily, there's a lot of really excellent research going on towards developing a therapeutic for COVID-19 that could be used in a more widespread way. While I would love to dive into each type of development individually, it would be hard to fit all of that in this post (without everyone, myself included, getting kind of science-d out). So I've decided to play favorites and talk about one therapeutic that is being developed at my alma mater.
Dr. Erik Procko from the University of Illinois at Urbana-Champaign has developed a way to trick SARS-CoV-2 into binding a decoy molecule, rather than to our cells. Usually the virus infects by using it's spike protein to bind to ACE2, a receptor protein on our cells' surfaces (as discussed in part 1 of this COVID trilogy). What Dr. Procko's lab has engineered is a fake-ACE2 protein that can be released into our bodies that would bind to all of the SARS-CoV-2 virus particles, and then never let go. This would incapacitate the virus, and keep it from binding to any of our actual ACE2 receptors on our cells, thereby stopping an infection even when the virus is present in our bodies.
The big question, with any viral treatment or vaccine or therapeutic... what if the virus mutates? The best part about this decoy-protein treatment that Dr. Procko developed is, it accounts for mutations. The virus has the capacity to mutate that spike protein, the one that would be bound by the decoy protein, such that the decoy ACE2 protein wouldn't be able to bind and incapacitate the viral particles anymore. However, if the spike protein were to mutate in such a way that the decoy couldn't bind to it, the virus would actually lose the ability to bind to our natural ACE2 receptors as well. This is because the decoy was designed to be extremely similar to the endogenous protein in our bodies, just a stronger version.
And like I said before, there are countless other therapeutics being developed currently such that hopefully soon we'll have an easier time treating patients who test positive for SARS-CoV-2, and keeping people from developing symptoms severe enough to land them in the hospital.
Now, however, onto the BREAKING NEWS as promised at the start of this post. Therapeutics are very important in the battle against COVID-19, however, everyone's been asking about something very different since quarantine started- when will we have a vaccine?
Vaccines take a long time to develop, test, and approve for public release, similar to what we talked about earlier with drug development. This is because a vaccine is usually a small dose of a weakened version of a pathogen, so that your body has a chance to develop it's response to the pathogen without dealing with a full-on infection. After your body sees an invader once, it can remember the response it used that worked best to combat the infection, so if that same invader rolls around again, you can mount a quicker response and experience fewer symptoms (if any at all).
At first, when I heard people talking about vaccines for COVID-19, I figured it was extremely optimistic to even think about. Vaccines are finicky and SARS-CoV-2 has proven itself to be a tricky virus to work with, so I wasn't expecting any promising news surrounding a vaccine for at least another year, or two... or three.
So I was pleasantly surprised to read about Pfizer's new RNA-based vaccine that has been shown to be around 90% effective in patients who become infected with SARS-CoV-2. This is a pretty impressive number, especially since the CDC has stated that the threshold of effectiveness they will require to release a COVID-19 vaccine to the public is only 50%.
RNA-based vaccines are a very new technology, that should be much cheaper to produce than the typical weaken-viral-particles vaccines. Basically, rather than introducing your body to an entire weak version of SARS-CoV-2, this type of vaccine introduces your cells to the first thing it will encounter once the virus successfully invades: RNA. SARS-CoV-2 is an RNA virus, so the genetic material it injects into human cells is RNA. This RNA will become DNA, this DNA will code for proteins that the virus needs to make more of itself, and the infection goes on. Specifically, the RNA used in Pfizer's vaccine is for the spike protein, the one your cells have to be the most prepared to defend against. The idea is your body develops antibodies specifically for this protein so that upon infection, your body has a response ready to tag the viral particles for degradation, and if the antibodies bind in a way that the spike protein cannot bind ACE2, the antibodies also buy your immune system some time by preventing the virus from invading your cells.
This is exciting, because results like 90% effective don't happen every day in science. This is a huge step forward in the COVID-19 research community, and hopefully means my projection of a couple of years for a vaccine being released to the public will be wrong.
There are still lots of other vaccine options being explored, and lots more testing to be done on Pfzier's vaccine too (RNA is hard to store, so actually producing and then storing and then shipping this vaccine will be a feat for researchers to tackle). But I'm happy to say we are moving forward, even quicker than we thought we could.
Until then, however, everyone needs to keep being good, and this is what I'm going to finish this trilogy with. There are treatment options on the way, and promising results from vaccine trials, and those facts should absolutely be beacons of hope for the world amidst this pandemic. However, everyone needs to keep on doing their part to keep other people safe while we wait for a vaccine or a treatment that is safe for the public. Just because we're getting closer to these options doesn't mean the virus going to disappear, this is something people are going to have to continue to think about and take responsibility for (probably for several more months, at least).
So I've said it many times before and I'll say it again, WEAR YOUR MASKS. Practice social distancing, and PLEASE don't go to parties. Please don't throw parties either. The more careful we are and the more conscious we are of how our actions will effect the state of the pandemic, the easier these months leading up to a treatment or vaccine will be.
Keep having Zoom-happy-hours, and keep on spending more nights in. Keep seeing people in groups smaller than 10. Keep meeting people outside. Keep working together by staying far apart. Keep your masks on, and your chins up. We will get through this as long as we stay strong, and there will be an end to this pandemic.
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