Paxlovid remains a lifesaving drug, but some patients may remain contagious during viral rebound

At a glance:
New study shows that viral rebound with Paxlovid is more common than previously believed.
Clinicians should counsel patients about the possible risk of transmitting virus during rebound.

A new study by Harvard Medical School researchers at Massachusetts General Hospital and Brigham and Women’s Hospital has found that one in five individuals taking nirmatrelvir-ritonavir therapy, commonly known as Paxlovid, to treat severe symptoms of COVID-19 had a positive test result and shed live potentially contagious virus following an initial recovery and negative test — a phenomenon known as virologic rebound. By contrast, people not taking Paxlovid experienced rebound only about 2 percent of the time.