deltatrials
Completed PHASE2 INTERVENTIONAL 2-arm NCT05567952

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

AN INTERVENTIONAL, EFFICACY AND SAFETY, PHASE 2, RANDOMIZED, DOUBLE-BLIND, 2-ARM STUDY TO INVESTIGATE A REPEAT 5-DAY COURSE OF NIRMATRELVIR/RITONAVIR COMPARED TO PLACEBO/RITONAVIR IN PARTICIPANTS AT LEAST 12 YEARS OF AGE WITH REBOUND OF COVID-19 SYMPTOMS AND RAPID ANTIGEN TEST POSITIVITY

Sponsor: Pfizer

Conditions COVID-19
Interventions nirmatrelvir placebo for nirmatrelvir ritonavir
Updated 16 times since 2022 Last updated: Sep 17, 2024 Started: Oct 19, 2022 Primary completion: Sep 27, 2023 Completion: Feb 9, 2024
This information is for research purposes only and is not medical advice. Consult a healthcare provider before making any medical decision.

This PHASE2 trial investigates COVID-19 and is currently completed. Pfizer leads this study, which shows 16 recorded versions since 2022 — indicating substantial longitudinal coverage. Longitudinal tracking of infectious disease trials helps identify durability of treatment effects.

Status Flow

~Nov 2022 – ~Dec 2022 · 30 days · monthly snapshot~Dec 2022 – ~Jan 2023 · 31 days · monthly snapshot~Jan 2023 – ~Feb 2023 · 31 days · monthly snapshot~Feb 2023 – ~Mar 2023 · 28 days · monthly snapshot~Mar 2023 – ~Aug 2023 · 5 months · monthly snapshot~Aug 2023 – ~Sep 2023 · 31 days · monthly snapshot~Sep 2023 – ~Oct 2023 · 30 days · monthly snapshot~Oct 2023 – ~Nov 2023 · 31 days · monthly snapshot~Nov 2023 – ~Dec 2023 · 30 days · monthly snapshot~Dec 2023 – ~Mar 2024 · 3 months · monthly snapshot~Mar 2024 – ~Apr 2024 · 31 days · monthly snapshot~Apr 2024 – ~Jul 2024 · 3 months · monthly snapshot~Jul 2024 – ~Sep 2024 · 2 months · monthly snapshot~Sep 2024 – ~Nov 2024 · 2 months · monthly snapshot~Nov 2024 – ~Sep 2025 · 10 months · monthly snapshot~Sep 2025 – present · 11 months · monthly snapshot

Change History

16 versions recorded

  1. Sep 2025 — Present [monthly]

    Completed PHASE2

  2. Nov 2024 — Sep 2025 [monthly]

    Completed PHASE2

  3. Sep 2024 — Nov 2024 [monthly]

    Completed PHASE2

  4. Jul 2024 — Sep 2024 [monthly]

    Completed PHASE2

  5. Apr 2024 — Jul 2024 [monthly]

    Completed PHASE2

▶ Show 11 earlier versions

  1. Mar 2024 — Apr 2024 [monthly]

    Completed PHASE2

    Status: Active Not Recruiting → Completed

  2. Dec 2023 — Mar 2024 [monthly]

    Active Not Recruiting PHASE2

  3. Nov 2023 — Dec 2023 [monthly]

    Active Not Recruiting PHASE2

  4. Oct 2023 — Nov 2023 [monthly]

    Active Not Recruiting PHASE2

    Status: Recruiting → Active Not Recruiting

  5. Sep 2023 — Oct 2023 [monthly]

    Recruiting PHASE2

  6. Aug 2023 — Sep 2023 [monthly]

    Recruiting PHASE2

  7. Mar 2023 — Aug 2023 [monthly]

    Recruiting PHASE2

  8. Feb 2023 — Mar 2023 [monthly]

    Recruiting PHASE2

  9. Jan 2023 — Feb 2023 [monthly]

    Recruiting PHASE2

  10. Dec 2022 — Jan 2023 [monthly]

    Recruiting PHASE2

    Status: Not Yet Recruiting → Recruiting

  11. Nov 2022 — Dec 2022 [monthly]

    Not Yet Recruiting PHASE2

    First recorded

Oct 2022

Trial started

Per CT.gov start date — pre-dates our first snapshot

Eligibility Summary

No eligibility information available.

Contact Information

Sponsor contact:
  • Pfizer
Data source: Pfizer

For direct contact, visit the study record on ClinicalTrials.gov .

Study Locations

Anaheim, United States , Andrews, United States , Athens, Greece , Bay City, United States , Beaver, United States , Blackfoot, United States , Brandon, United States , Brownsville, United States , Butte, United States , Canoga Park, United States and 52 more locations