WASHINGTON (AP) – Pfizer’s COVID-19 pill appears to offer little or no benefit to younger adults, while reducing the risk of hospitalization and death for high-risk seniors, according to a major study published Wednesday.
The results of an Israeli study of 109,000 patients are likely to renew questions about the US government’s use of Paxlovid, which has become the treatment of choice for COVID-19 because of its convenience at home. The Biden administration has spent more than $10 billion to buy the drug and make it available at thousands of pharmacies through its test-and-treat initiative.
The researchers found that Paxlovid reduced hospitalizations among people 65 and older by about 75% when given soon after infection. That’s consistent with previous results used to approve the drug in the United States and other nations.
But people between the ages of 40 and 65 saw no measurable benefit, according to the analysis of medical records.
The study has limitations due to its design, which pooled data from a large Israeli health system rather than enrolling patients in a randomized, control-group trial — the gold standard for medical research.
The findings reflect the changing nature of the pandemic, where the vast majority of people already have some protection against the virus due to vaccination or previous infection. Especially for younger adults, this reduces the risk of serious COVID-19 complications. The Centers for Disease Control and Prevention recently estimated that 95% of Americans age 16 and older have acquired some level of immunity to the virus.
“Paxlovid will remain important for people at highest risk for severe COVID-19, such as seniors and those with compromised immune systems,” said Dr. David Boulware, a researcher and physician at the University of Minnesota, who was not involved in the study. “But for the vast majority of Americans who are now eligible, this doesn’t really have much benefit.”
A Pfizer spokesman declined to comment on the results, which were published in the New England Journal of Medicine.
The US Food and Drug Administration approved Paxlovid late last year for adults and children 12 and older who are considered high-risk due to conditions such as obesity, diabetes and heart disease. More than 42% of American adults are considered obese, representing 138 million Americans, according to the CDC.
At the time of the FDA decision, there were no options for treating COVID-19 at home, and Paxlovid was considered critical to curbing hospitalizations and deaths during the pandemic’s second winter wave. The drug’s results were also far stronger than a competing pill from Merck.
The FDA made its decision based on a Pfizer study in high-risk patients who had not been vaccinated or treated for previous COVID-19 infection.
“These people do exist, but they’re relatively rare because most people have now either been vaccinated or they’ve been infected,” Boulware said.
Pfizer reported earlier this summer that a separate study of Paxlovid in healthy adults – vaccinated and unvaccinated – showed no significant benefit. These results have not yet been published in a medical journal.
More than 3.9 million prescriptions for Paxlovid have been filled since the drug was approved, according to federal records. A course of treatment is three pills twice a day for five days.
A White House spokesman on Wednesday pointed to several recent papers suggesting that Paxlovid helps reduce hospitalizations among people 50 and older. The studies have not been published in peer-reviewed journals.
“The risk of severe outcomes from COVID is along a gradient, and the growing body of evidence shows that individuals between the ages of 50 and 64 may also benefit from Paxlovid,” Kevin Munoz said in an emailed statement.
Administration officials have worked for months to increase the use of Paxlovid, opening thousands of sites where patients who test positive can fill a prescription. Last month, US officials further expanded access by allowing pharmacists to prescribe the drug.
The White House recently signaled that it may soon stop buying covid-19 vaccines, drugs and tests, shifting responsibility to the private insurance market. Under that scenario, insurance companies can set new criteria for when they will pay for patients to receive Paxlovid.
Follow Matthew Perrone on Twitter: @AP_FDAwriter
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. AP is solely responsible for all content.