Rebound Phenomenon After Nirmatrelvir/Ritonavir Treatment of Coronavirus Disease 2019 (COVID-19) in High-Risk Persons

Clin Infect Dis. 2023 Feb 8;76(3):e537-e539. doi: 10.1093/cid/ciac481.


In a cohort of 483 high-risk patients treated with nirmatrelvir/ritonavir for COVID-19, 2 patients (0.4%) required hospitalization by day 30. Four patients (0.8%) experienced rebound of symptoms, which were generally mild, at a median of 9 days after treatment, and all resolved without additional COVID-19-directed therapy.

Keywords: COVID-19; paxlovid; rebound phenomenon; therapeutics.

MeSH terms

  • COVID-19 Drug Treatment
  • COVID-19*
  • Humans
  • Ritonavir* / therapeutic use


  • nirmatrelvir
  • Ritonavir