Antivirals may change the course of the pandemic
New pills to treat COVID-19 are now showing promise at curbing illness and saving lives.
Years before the rise of the COVID-19 pandemic, virologists started a quest to find drugs called antivirals that can protect people against emerging coronaviruses. The journey has been slow and failures have been frequent. But with Britain’s authorization this week of Merck’s new drug molnupiravir, and a cash infusion into antiviral R&D, the outlook for these treatments is getting much brighter.
Unlike vaccines that can prevent infection, antivirals act as a second line of defense, slowing down and eventually arresting progression of a disease when infections occur. They’re also important when effective vaccines aren’t available against viral diseases, as is the case for HIV, hepatitis C, and herpes.
But developing antivirals is an expensive and difficult endeavor. That’s especially true for acute respiratory diseases, for which the window for treatment is short. In the case of SARS-CoV-2, the coronavirus that has unleashed the devastating COVID-19 pandemic, researchers have resorted to repurposing old drugs or compounds that were being tested against other diseases.
“That’s typical,” says Katherine Seley-Radtke, a medicinal chemist at the University of Maryland, Baltimore County. “Every time a new virus emerges or an old one re-emerges, you pull out what’s there in the cupboard to see what works.”
So far remdesivir, originally developed by biopharmaceutical company Gilead Sciences for hepatitis C and Ebola infections, is the only antiviral drug approved by the U.S. Food and Drug Administration to treat COVID-19. It must be administered via injection while a patient is in the hospital, although there isn’t consensus regarding its ability to treat COVID-19.
Experts think oral antivirals like Merck’s are set to be the most promising tools to work alongside vaccines at combating the pandemic. Provided they are affordable, antivirals could be especially important among people who remain unvaccinated either out of choice or due to limited access and economic constraints.
By Priyanka Runwal
Published November 5, 2021 – National Geographic Society