Pfizer starts study of oral drug for preventing COVID-19


Pfizer has started testing an oral antiviral pill aimed at preventing COVID-19 infections, the pharmaceutical company announced Monday.
The drug, PF-07321332, is designed to block the main enzyme the coronavirus needs to multiply, Pfizer said. PF-07321332 will be co-administered with a small dose of ritonavir, an antiviral that is used in combination with other medications to treat HIV.
"If successful, we believe this therapy could help stop the virus early — before it has had a chance to replicate extensively — potentially preventing symptomatic disease in those who have been exposed and inhibiting the onset of infection in others," Mikael Dolsten, Pfizer's chief scientific officer and president of worldwide research, development, and medical, said in a statement.
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This antiviral could not only help treat people who will not get vaccinated against COVID-19, but would also be beneficial in countries where they expect it will take several years to get all residents fully vaccinated, Axios notes.
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Catherine Garcia has worked as a senior writer at The Week since 2014. Her writing and reporting have appeared in Entertainment Weekly, The New York Times, Wirecutter, NBC News and "The Book of Jezebel," among others. She's a graduate of the University of Redlands and the Columbia University Graduate School of Journalism.
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