Frontiers | Real-world effectiveness and safety of nirmatrelvir-ritonavir (Paxlovid)-treated for COVID-19 patients with onset of more than 5 days: a retrospective cohort study
A study in Guangzhou, China, with 248 COVID-19 patients found that Paxlovid is effective and safe when given within 10 days of onset, reducing viral load
Effectiveness decreases after 10 days, but multiple cycles may help if the viral load remains high
