February 15, 2023 – A latest study shows that individuals who took the antiviral drug paxlovid to treat COVID-19 infections weren't more more likely to develop consecutive bouts of the virus.
The results provide clarity on fears that the usage of paxlovid, which stops the virus from spreading within the body, increases the chance of COVID-19 spreading again.
“A rebound is the recurrence of symptoms and an increase in viral load after a period of recovery,” the Center for Infectious Disease Research and Policy explained in a Summary the study.
The researchers found that the relapse rate was similar in patients who received paxlovid, one other antiviral called Lagevrio, or no antiviral medication, starting from 4.5% to six.6%.
The study was published on Monday within the magazine The Lancet Infectious Diseases and included 4,592 people in Hong Kong who were hospitalized inside 3 days of a COVID diagnosis. The study period was from February 26, 2022 to July 3, 2022, the period when the omicron subvariant BA.2.2 was predominant.
The study also found that the chance of rebound was related to age 18 to 65 (in comparison with older patients), chronic medical conditions, and steroid treatment. Another finding the authors considered vital was that paxlovid didn't appear to make rebounds worse. People who received paxlovid and had a rebound infection weren't more more likely to need intensive care, need a ventilator to breathe, or die.
In a comment Infectious disease expert Nicola Petrosillo, MD, noted in a study published parallel to the study that an unexpected finding was the connection between vaccination status and rebound.
“Surprisingly, the likelihood of a renewed increase in viral load in patients who [Paxlovid] significantly reduced in people who were not fully vaccinated,” he noted.
Petrosillo, who treated some of the earliest COVID cases in Rome said the study's conclusion was that it was vital to proceed offering antiviral drugs to people at high risk of becoming seriously unwell with COVID.