COVID-19 returns even after people take Paxlovid

Some coronavirus-positive patients who have completed treatment of the antiCOVID drug Paxlovid are rebounding into illness, and experts are urging people to be cautious if they develop COVID-like symptoms again and become infectious.

It’s unclear how often “post-Paxlovid rebound” occurs, but University of California, San Francisco Department of Medicine chair Dr. Robert Wachter said he knows of at least one per- son who completed Paxlovid treatment and then became infectious again, spreading the virus torelatives.

“It can happen,” Wachter tweeted. “If you develop recurrent symptoms and have a (positive) rapid test, you are infectious. Please act accordingly.”

Los Angeles County Public Health Director Barbara Ferrer said post-Paxlovid COVID-19 relapses are “real.”

“They’ve happened in a significant enough number that they’ve been noticed by lots of folks in lots of different places,” she said.

The U.S. Food and Drug Administration (FDA) autho- rized the use of Merck’s molnupiravir pill for treatment. The pill is cleared for use by adults 18 and older who have tested positive for COVID-19 and are at high risk of being hospitalized or dying.

The FDA said it is aware of reports of COVID-19 symptoms returning following the completion 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 FDA said that in the Paxlovid clinicaltrial, there have been some patients — about 1% to 2% — who tested negative and then became positive. The finding wasn’t only in people who took Paxlovid; it also occurred in those who took the placebo.

“Yet, judging by all the anecdotes, rebound sure seems more common than that — we’re waiting for good data,” Wachter tweeted. Wachter suggested that a person who has completed a course of Paxlovid and then tests positive again should be considered infectious.

Paxlovid’s clinical trial data were collected when the Delta variant of the coronavirus dominated nationwide, before the rise of the far-more-transmissible Omicron family that’s circulating now.