TS: Once some amount of the virus gets in your body, it finds the right cells that it needs to infect. These viruses don't just infect any cell. It will be specific in some way. There is a protein on the outside of the cell called a receptor that the virus binds to in order to get inside your cells. These coronaviruses, especially the one that comes with COVID-19, seem to generally be contained in your respiratory tract.
Once some amount of cells are infected in your respiratory tract, those infected cells create thousands of copies of new virus cells that can spread to other cells. Ultimately, you could have millions and millions of copies of the virus in your respiratory tract.
DTH: How does EIDD-2801 work to fight this kind of disease?
TS: Viruses replicating in the presence of this drug create genomes and viruses that are defective.
The drug itself looks like one of the building blocks of life, like the DNA and RNA in our cells. Similarly, coronaviruses have RNA for genomes and while they're replicating themselves in cells, they're stealing blocks of RNA from our cells to make their genome. In the presence of EIDD-2801, which looks like a building block of RNA but is defective, the virus incorporates EIDD-2801 into its genome.
That subsequent genome does not work because EIDD-2801 doesn't work like a normal building block of RNA. In that way, you essentially drive the virus to extinction in a person’s body. That’s the hope.
DTH: Why is it significant that EIDD-2801 can be administered in pill form?
TS: An oral drug is advantageous because it is easy to take. Everybody has swallowed a pill before. It means that the access to this drug is potentially greater than one that has to be administered intravenously, which can’t be done at home. If you could get medicine to someone in their home, you could potentially lessen that person’s disease and their ability to transmit it to their family members by medicating them in their household.
DTH: What's UNC’s role in the development of this drug?
TS: What we do at UNC is work with companies and other academic institutions on the preclinical development of antiviral drugs and therapies. In the process of getting approval from the FDA, there is a laundry list of things that you need to show before a drug is given to a person. The preclinical development process would be checking those boxes. As part of that, we study how the drugs work against coronavirus in cells and in mouse models of coronavirus disease. So that's what we've been doing, and everything that happens after that stage we don't have direct involvement.
DTH: What should people know about the importance of drugs like EIDD-2801?
TS: In the past 20 years, we’ve seen three new human coronaviruses emerge through wild animals. Due to the great diversity found in nature, it is likely this will continue in the future. So we need to be better positioned for SARS-CoV-3 if it does in fact emerge, such that we don’t end up with a pandemic.
If we had drugs and therapeutics or vaccines on the shelf that were approved and didn’t need to be tested further, they could be immediately deployed to places where there are outbreaks. I think this current situation, although grave and depressing, will potentially give us an opportunity to better position ourselves for what I think is the likely emergence of another novel coronavirus sometime in the near future.