A Study to Learn About a Repeat 5-Day Treatment With the Study Medicines (Called Nirmatrelvir/Ritonavir) in People 12 Years Old or Older With Return of COVID-19 Symptoms and SARS-CoV-2 Positivity After Finishing Treatment With Nirmatrelvir/Ritonavir

Summary

The purpose of this study is to learn about the safety and effects of nirmatrelvir/ritonavir for the potential treatment of COVID-19 rebound. The study is seeking participants who: * Have completed treatment with nirmatrelvir/ritonavir * Have a rebound in COVID-19 symptoms * Are SARS-CoV-2 (COVID-19) positive All study medications will be taken 2 times a day by mouth for 5 days. The first dose of study medication is taken at the study clinic and the rest at home. We will examine the experiences of people receiving the study medicines to those who do not. This will help us determine if the study medicines are safe and effective. People taking part will be in this study for about 24 weeks. Enrolled participants will need to visit the study clinic at least 8 times during the study.

Timeline

Start

2022-10-19

Primary completion

2023-09-27

Completion

2024-02-09

Publications

• Zhang W, Terra SG, Weinstein EA, Bramson C, Leister-Tebbe H, Baniecki ML, Guan S, Agyemang A, Antonucci S, Wisemandle W, Hammond J. Retreatment With Nirmatrelvir/Ritonavir Following Return of COVID-19 Symptoms and SARS-CoV-2 Positivity. Clin Infect Dis. 2026 Feb 9;82(1):e33-e40. doi: 10.1093/cid/ciaf548.
• Baniecki ML, Guan S, Rai DK, Yang Q, Lee JT, Hao L, Weinstein E, Hyde C, Cardin RD, Soares H, Hammond J. Integrated virologic analysis of resistance to nirmatrelvir/ritonavir in individuals across four phase 2/3 clinical studies for the treatment of COVID-19. EBioMedicine. 2025 Aug;118:105819. doi: 10.1016/j.ebiom.2025.105819. Epub 2025 Jun 30.

Drugs

Indications