Why You Shouldn’t Worry About a Paxlovid ‘Rebound’
Ever since news reports that President Biden had a “rebound” infection of COVID-19 after taking the antiviral drug Paxlovid, our primary care doctors in Delray Beach have heard questions from some of our patients who are now concerned about using it.
Here’s why you should not hesitate to take it if you’re eligible.
Paxlovid is a prescription antiviral drug manufactured by Pfizer, specifically to treat mild to moderate symptoms of COVID-19. Studies show it is nearly 90 percent effective at preventing serious illness and hospitalizations.
The U.S. Food and Drug Administration (FDA) authorized Paxlovid if:
- you tested positive for COVID-19
- you’re at least 18 years old, or at least 12 years old and weigh at least 88 pounds
- you have one or more risk factors for severe COVID-19 (i.e., are immunocompromised, have one or more underlying medical conditions, or are 65 or older)
It is an oral pill taken at home twice a day for five days. It is not recommended for those taking certain medications, because Paxlovid can interact with some drugs and cause serious side effects, the FDA says. (https://www.fda.gov/media/158165/download)
The Centers for Disease Control and Prevention (CDC) recommends that people begin taking Paxlovid as soon as possible after symptoms first appear or after testing positive for the virus, and no later than within five days of when symptoms start.
“Don’t delay: Treatment must be started within days of when you first develop symptoms to be effective,” the CDC says.
The CDC defines so-called “rebound” cases as “characterized by a recurrence of COVID-19 symptoms or a new positive viral test after having tested negative.”
Rebound cases shouldn’t be confused with reinfection: Rebound cases occur within days of the original infection; reinfection happens weeks or months after recovery from COVID-19.
Symptoms in rebound cases are usually milder than the initial illness, and sometimes may not be present at all. This was the case with Biden, 79, whose rebound case was caught only because of the repeated testing initiated due to his age and position.
Approximately 5 percent of Paxlovid users have experienced rebound cases so far, White House COVID response coordinator Dr. Ashish Jha said at a news conference in June.
Albert Ko, an epidemiologist at the Yale School of Public Health, told NBC News that regardless of rebound cases, the message is clear: Paxlovid is working.
“Paxlovid is doing what it’s supposed to do: prevent us from getting life-threatening COVID,” he said. “Even though these rebounds are happening, it’s preventing the severe outcomes.”
Is it the Paxlovid?
And despite the reports of Paxlovid-related rebounds, it may be the virus itself—or some people’s reactions to it—that could be causing rebounds.
In studies of more than 2,200 COVID-19 patients during clinical trials, Pfizer said there were rebound cases in both those taking the drug and those who took the placebo, CNN reports.
Another researcher, however, Dr. Michael Charness of the Veterans Administration (VA) Medical Center in Boston, studied more than 1,000 cases of COVID-19 diagnosed between December and March in players and supports staff of the National Basketball Association (NBA). His researcher team didn’t find a single rebound case among those who had not taken Paxlovid, he told CNN.
But another study, published online this month, found that around a third of those with COVID-19 will experience a rebound of their symptoms, regardless of whether they’ve taken Paxlovid, NBC News reported.
The study has not been peer-reviewed yet, but study co-author Davey Smith, chief of infectious diseases at the University of California, San Diego School of Medicine, told NBC, “It happens all the time. . . . It’s just the variability in the natural course of the infection.”
Paul Sax, clinical director of the division of infectious diseases at Brigham and Women’s Hospital in Boston, agreed.
“In some ways, that’s the natural history of all respiratory viral infections,” he told NBC. “There are good days and bad days, and they they eventually get better.”
Paxlovid is not technically a cure for COVID-19, but a treatment that in clinical trials cut the risk of hospitalizations and deaths by 89 percent by interrupting the replication of the virus in the body.
This may help explain why you can still transmit the virus even during a course of Paxlovid, because the virus is still present, although in smaller amounts. And it is possible to infect others during a rebound case, even if you don’t have symptoms.
“People who experience rebound are at risk of transmitting to other people, even though they’re outside what people accept as the usual window for being able to transmit,” Charness told CNN.
Nevertheless, the drug is still a potent weapon in the fight against the coronavirus.
Scott Roberts, an assistant professor of infectious diseases at Yale School of Medicine, maintains the risk of rebound is worth if it lessens symptoms and keeps people out of the hospital.
“Preventing these bad outcomes is the main benefit of Paxlovid, even in spite of the potential rebound,” he told NBC’s Make It.
“I would strongly suggest that people who qualify for Paxlovid take it and don’t worry about the rebound risk,” he added.