Pfizer Covid drug Paxlovid could scale back danger of lengthy Covid: research

A prescription for Pfizer’s Paxlovid tablets outside of his home in Philadelphia, Pennsylvania on April 25, 2022. (Photo by Rachel Wisniewski/For the Washington Post)

Rachel Wisniewski | The Washington Post | Getty Images

people who take PfizerAntiviral Covid treatment Paxlovid shortly after infection may reduce the risk of long-term Covid illness, regardless of age, vaccination status or infection history, new research suggests.

The study, published Thursday in the journal JAMA Internal Medicine, found that people who took Paxlovid within five days of testing positive for Covid saw a 26% lower risk of long-term Covid than those who didn’t take it . More than 35,000 people took the oral Covid pill in the study, while 246,000 did not.

Only people eligible for Paxlovid under an emergency authorization were enrolled in the study. This includes adults over 50 or those with an underlying medical condition such as high blood pressure or diabetes.

The results suggest Paxlovid’s benefits may extend beyond what the drug was designed for, which is treating adults and children who are at higher risk of ending up in hospital or dying from Covid infection. The drug still showed its intended benefit in the study, reducing the risk of death by 47% and the risk of hospitalization by 24% about a month after initial infection.

The new study comes as researchers work to close the knowledge gap about long Covid, an often debilitating condition with limited data and no proven treatment available.

According to the Centers for Disease Control and Prevention, long covid refers to new, recurring, or ongoing health problems more than four weeks after an initial covid infection. These problems can include fatigue, trouble breathing, chest pain, and brain fog, and can last for weeks, months, or even years. The CDC estimates that 1 in 5 Covid survivors ages 18 to 64 and 1 in 4 survivors age 65 or older have an ongoing health problem that could be due to a previous infection.

Most of what is known about long-term Covid is that certain people are at higher risk, and the Covid vaccine likely offers some protection against that, says Dr. Jessica Bender, Co-Medical Director at the University of Washington Post-COVID-19 Rehabilitation and Recovery Clinic. She called the new study “very exciting and promising” because it is the first to show a link between Paxlovid and a reduced risk of long Covid.

dr Anita Chopra, a board-certified internal medicine physician who treats patients at a University of Washington primary care medical center, added that prescribers can use the study results to encourage uptake of Paxlovid. Eligible patients will have more peace of mind knowing the drug can result in a significant reduction in their chances of developing the post-Covid condition, she said.

However, Chopra acknowledged that the study was an observational study, meaning the researchers observed participants who did or did not take Paxlovid without intervening. It wasn’t a randomized controlled trial — considered the gold standard for clinical research — where researchers can step in and better investigate a possible cause-and-effect relationship between taking a drug like Paxlovid and an outcome.

Bender emphasized the need to conduct a randomized controlled trial to “replicate these results.”

She said the study’s other limitation was that participants would be identified using health databases maintained by the Department of Veterans Affairs. According to Bender, researchers need to conduct studies on other patient populations outside of this healthcare system.

The study comes as Paxlovid moves closer to receiving full approval from the Food and Drug Administration, with the agency’s advisors voting overwhelmingly in support of the drug last week. The FDA is expected to make a decision in May.

More than 12 million cycles of Paxlovid have been shipped to pharmacies across the United States, according to the latest federal data. About 8 million Americans have taken the drug, with about 1.3 million doses available nationwide.

Correction: Bender said the study’s other limitation was that participants were identified using health databases maintained by the Department of Veterans Affairs. In a previous version, the name of the department and the last name of the doctor were incorrect.