Pfizer’s development is still one of the first oral antiviral drugs created specifically to fight the coronavirus. The drug, named PF-07321332, belongs to the class of antiviral agents – protease inhibitors.
Protease is an enzyme critical to viral replication mechanisms. Protease inhibitors have already been developed for the treatment of HIV / AIDS and hepatitis C.
“Protease inhibitors such as PF-07321332 are designed to block the activity of the main protease enzyme that the coronavirus needs to replicate,” Pfizer explains in a recent statement. “Co-administration with a low dose of ritonavir will help slow the metabolism or breakdown of PF-07321332 so that it stays in the body for longer periods of time at higher concentrations, thereby working continuously to help fight the virus.”
To date, two double-blind, placebo-controlled clinical trials are underway using the oral combination of PF-07321332 and ritonavir. Over the next few months, 3,000 people will be recruited to continue testing.
At the end of August, Pfizer also began to study the effect of the drug on patients at high risk of severe cases of COVID-19. Researchers will determine if PF-07321332 shortens the duration and severity of COVID-19 symptoms in healthy adults. 1140 people are planned to take part in this test.
According to the company, home treatment of coronavirus with pills should be started within three days after the first symptoms of COVID-19 appear. Therapy involves taking a pill every 12 hours for five days.