Some coronavirus-positive patients who have stopped treatment with the anti-COVID drug Paxlovid are on their way back to disease, and experts urge people to be careful if they develop COVID-like symptoms again and become contagious.
It is unclear how often “post-Paxlovid rebound” occurs, but the chairman of the UC San Francisco Department of Medicine, Dr. Robert Wachter, said he knows of at least one person who completed Paxlovid treatment and then became contagious again and spread the virus to other family members.
“It can happen,” Wachter said tweeted. “If you develop recurrent symptoms and have one [positive] quick test, you are contagious. Please act accordingly. “
Los Angeles County Public Health Director Barbara Ferrer said post-Paxlovid COVID-19 relapses are “real.”
“They have happened in a significant enough number that they have been noticed by many people in many different places,” she said.
In a announcement On its website, the U.S. Food and Drug Administration said it is aware of reports of COVID-19 symptoms returning after the end of Paxlovid treatment. “In some of these cases, patients tested negative on a direct SARS-CoV-2 viral test and then tested positive again,” the FDA said.
The agency said that in the clinical trial of Paxlovid, some patients – about 1% to 2% – tested negative and then became positive. The finding was not only in people taking Paxlovid; it also occurred in those who took placebo.
“Still, judging by all the anecdotes, rebound certainly seems more common than that – we’re waiting for good data,” Wachter tweeted. Wachter suggested that a person who has completed a Paxlovid cure and then tests positive again should be considered contagious.
Those who want to be especially careful about the risk of infecting others may want to consider wearing a mask in any indoor environment, even around family members from the same household, in a a few more days or maybe a week when Paxlovid treatment is complete, Wachter said.
Even a quick negative test after completing the five-day course of Paxlovid can provide false assurance that a person is not contagious. A negative quick test result suggests that a person is probably not contagious, but there is still a small chance – maybe 1% – that a person in this situation can test negative and still be contagious, Wachter wrote.
“Wearing masks for a few more days seems reasonable if you are careful,” he said.
Post-Paxlovid COVID-19 rebound still seems to be unusual, said Wachter, and is not harmful to the healthy patient. Wachter said news of the recovery should not deter people from taking Paxlovid because of its high efficacy against serious illness and death.
In addition, it is plausible, but not proven, that “lowering viral load quickly (which Paxlovid does) can lower the risk of long-term COVID and make people less contagious,” Wachter wrote.
The FDA agreed that the reports of post-Paxlovid COVID-19 rebound do not change scientists’ overall view that the drug is highly effective.
“Most importantly, there was no increased incidence of hospitalization or death or development of drug resistance,” the FDA said. “Thus, these reports do not alter the conclusions of Paxlovid’s clinical trials, which showed a marked reduction in hospitalization and death.”
The FDA said patients should wear a mask and stay home and isolate themselves if they have symptoms of COVID-19, whether or not they have been given an antiviral drug like Paxlovid.
A report from scientists at UC San Diego submitted online Wednesday analyzed the case history of a traveler who returned to the United States after a trip to South Africa and had recurrent COVID-19 after completing a Paxlovid course. The researchers said the most likely possibility of the recurring symptoms was “insufficient drug exposure.”
Among those who observed the setback was Dr. Paul Sax, an infectious disease expert at Harvard Medical School, told in a recent blog post post how a patient with COVID-19 recovered quickly after taking Paxlovid, but a week later called him back and said that she relapse. Although the symptoms were not as bad as her original illness, quick test results showed that she was “clearly positive again.”
“Her biggest concern was getting out into the world again without infecting anyone. She was really not that sick; she just wanted advice on when she could return to work and start socializing again,” Sax wrote. close contact with others until the test is ready, “I said.
The patient recovered completely and she started testing negative a few days later, Sax wrote.