Pfizer released additional data about its pill to treat COVID-19 that shows it was effective in preventing hospitalization and death when taken by people with mild to moderate illness within a few days of first symptoms.
The medicine, called Paxlovid, is taken twice a day for five days in combination with a second medicine called ritonavir, a generic antiviral.
The results from a study involving more than 2,200 people at high risk for developing serious COVID-19 found the drug reduced the risk of hospitalization or death by 89%, compared with a placebo, when taken within three days of first symptoms of illness. When taken within five days, the drug reduced the risk of hospitalization and death by 88%.
"If you would treat 100,000 patients of this type with Paxlovid, you would prevent more than 5,500 hospitalizations and save some 1,100 lives," Pfizer's chief scientific officer Mikael Dolsten tells NPR.
Preliminary results from a second study showed a 70% reduction in hospitalization risk among several hundred people at lower risk for severe disease.
The company also looked at the effect of the drug on suppressing the amount of virus in the body, the so-called viral load, and found it led to a tenfold drop compared with a placebo. A reduction in viral load could reduce people's infectiousness.
Reactions to the drug and placebo were similar and most were mild, Pfizer said.
Pfizer said it has submitted the results to the Food and Drug Administration. If the agency authorizes the medicine, the U.S. government has a contract with Pfizer to buy 10 million courses for $5.3 billion.