Pfizer’s own studies found that Paxlovid reduced the risk of hospitalizations and deaths by 88 percent in unvaccinated individuals at high risk for severe Covid, so long as the drug was taken within the first five days of symptom onset.
The new research, published on Wednesday in The New England Journal of Medicine, showed the drug to be effective mostly in older Covid patients.
“The big story is that it works, and saves quite a few lives and hospitalizations,” said Dr. Ronen Arbel, the study’s first author and a health outcomes expert at Clalit Health Services in Tel Aviv. “It’s very important that it’s helpful for older patients.”
Other authors included Yael Wolff Sagy, Dr. Doron Netzer and Ariel Hammerman, all affiliated with Clalit Health Services, a large health care provider in Israel. The researchers reviewed medical records of almost 110,000 members of Clalit who tested positive for Covid from January through March, when the Omicron variant was dominant.
The patients were at least 40 years old and were considered to be at high risk for severe disease. Most had either been vaccinated, previously infected with Covid, or both. The mean age of patients was 60, and more than half were women.
About 4,000 were treated with Paxlovid, and the medication was highly effective when administered to individuals 65 and over, the researchers found.