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
Last updated:
Last updated
The date of the most recent update for each trial record in the Canadian Clinical Trial Search Portal.
2026-07-18
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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
Intervention/treatment:
Intervention/treatment
Name given to the drug used in the clinical trial. This may be a code name, a chemical name of the active ingredient, a non-proprietary name or brand name.
NIRMATRELVIR (PF-07321332) / RITONAVIR
Medical condition:
Medical condition
The disease or condition that's being studied in the clinical trial.
CORONAVIRUS DISEASE (COVID-19)
Protocol code:
Protocol Code
An alpha-numeric sequence generated by the sponsor that can vary in length. Used as a reference to help identify a specific clinical trial protocol. Formerly referred to as 'protocol number'.
C4671042
Control number:
Control number
A unique 6-digit identification number Health Canada assigns to each clinical trial application.
268341
Status:
Trial Status
The status for the clinical trial as a whole. Note that the status for each site may be different and should always be confirmed with the clinical trial sponsor. Health Canada uses information provided by the sponsor to an international clinical trial registry to determine status values for each clinical trial. Status values on the portal can include:
• Not yet recruiting - Participants are not yet being recruited or enrolled at any site. • Recruiting - Participants are currently being recruited. • Active, not recruiting - The clinical trial is ongoing but new participants are not currently being recruited or enrolled. • On hold - The clinical trial has been temporarily stopped, but it may start again. • Closed - The clinical trial has either ended normally and participants are no longer being examined or treated, or it has stopped early and will not start again. • Unknown - The status of the clinical trial has not been verified in the registry in the last 2 years. Please contact the sponsor. • No match, ongoing - Please contact sponsor for status information. • Other - Please contact sponsor for status information.
Closed
Approved:
Approved
The date that the clinical trial has been determined to meet Health Canada’s regulatory requirements. For drug clinical trials, this means that a no objection letter or an authorization was issued.
October 28, 2022
Date Completed:
Date completed
The date of the last participant’s last visit in the global study. The completion date may be actual or estimated, depending what was provided to the registry. Estimated completion dates may be in the past or future.
Trial phase:
Trial phase
The stage of a clinical trial, based on factors such as the objectives of the trial and number of participants. Phase data displayed in the portal is taken from international registry data.
For more information see "Phases of drug trials" on the Definitions webpage
This is an external link. The information is not authorized by the Government of Canada.
Eligibility
Eligibility
The characteristics people must have or the requirements they must meet to participate in the clinical trial. Eligibility criteria include both inclusion criteria (must have for a person to participate) and exclusion criteria (prevent a person from participating).
Review the exact criteria from the registry or the sponsor before making a decision to participate. The following values may be available on the portal:
Sex: an eligibility criteria based on biological characteristics. Information in the portal is based on available data and will default to 'all' when no other data is available.
Age: The age a person must be to participate in the clinical trial.
Accepts Healthy Volunteers: People who do not have the disease or condition can participate in the clinical trial.
Sex:
ALL
Age
12 Years and older
Accepts healthy volunteers:
No
Contacts and locations
Contact
Contact
Information for an individual or organisation that can respond to questions about this clinical trial. This information comes from the international registry.
The sponsor conducts the clinical trial and is responsible for every aspect. For example this could be a company, a university or an individual researcher.
