COVID-19Phase 3NCT05261139
EPIC-Peds: A Study to Learn About the Study Medicine Called PF-07321332 (Nirmatrelvir)/Ritonavir in Patients Under 18 Years of Age With COVID-19 That Are Not Hospitalized But Are at Risk for Severe Disease
A Phase 3 study testing nirmatrelvir and ritonavir in people with COVID-19, run by Pfizer at 73 sites in 7 countries.
Trial summary
The purpose of this clinical trial is to learn about the safety, pharmacokinetics (pharmacokinetics helps us understand how the drug is changed and eliminated from your body after you take it), and efficacy (how well a study treatment works in the study) of the study medicine (called nirmatrelvir/ritonavir) for… Read more about this study
- Who is it for?
- Ages 0 to 17 years
- Conditions the study is for
- COVID-19
- What is being tested?
- nirmatrelvir and ritonavir
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 160 participants
- Where
- 73 sitesin 7 countries
- Study dates
- 7 Mar 2022to 30 Jul 2026
- Phase
- Phase 3
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 0 to 17 years
- All sexes
- No healthy volunteers
- Child
Who may be able to join
- Male and female, age 0 to < 18 years, able to swallow for some participants
- Confirmed SARS-CoV-2 infection within 72 hours prior to enrollment
- Initial onset of COVID-19 signs/symptoms within 5 days prior to the day of enrollment and at least 1 of the specified COVID-19 signs/symptoms present at enrollment
- Has at least 1 characteristic or underlying medical condition associated with an increased risk of developing severe illness from COVID-19
Who cannot join
- History of or need for hospitalization for the medical treatment of COVID-19
- Total bilirubin >=2X upper limit of normal (ULN) (except for Gilbert's syndrome)
- Receiving dialysis or have known moderate to severe renal impairment
- Suspected or confirmed concurrent active systemic infection other than COVID-19
- History of hypersensitivity or other contraindication to any of the components of the study intervention
- Current or expected use of any medications or substances that are highly dependent on CYP3A4 for clearance or strong inducers of cytochrome P450 (CYP)3A4
Show all 9Show fewer
- Has received or is expected to receive antibody treatment, antiviral treatment or convalescent COVID-19 plasma
- Participating in another interventional clinical study with an investigational compound or device, including those for COVID-19 through the study follow up
- Females who are pregnant or breastfeeding
Trial locations and contacts
73 sites in 7 countries. Contact the study team or a site near you to ask about taking part.
73 sites in 7 countries
United States50 sites, 24 recruiting
- Terminated
University of New Mexico Hospital, COVID-19 Research Clinic
Albuquerque, New Mexico, 87102
- Terminated
University of New Mexico Clinical and Translational Science Center
Albuquerque, New Mexico, 87106
- Recruiting
Children's Healthcare of Atlanta - Arthur M. Blank Hospital
Atlanta, Georgia, 30329
- Not yet recruiting
Johns Hopkins Hospital
Baltimore, Maryland, 21287
- Active, not recruiting
Boston Medical Center
Boston, Massachusetts, 02118
- Not yet recruiting
Suny University at Buffalo
Buffalo, New York, 14203
- Terminated
Clinical and Translational Research Center
Chapel Hill, North Carolina, 27514
- Terminated
investigational Drug Services Pharmacy, UNC Hospitals
Chapel Hill, North Carolina, 27514
- Terminated
UNC Children's Hospital
Chapel Hill, North Carolina, 27514
- Terminated
UNC Global Clinical Research North
Chapel Hill, North Carolina, 27514
- Terminated
University of North Carolina Medical Center
Chapel Hill, North Carolina, 27599
- Active, not recruiting
Ann & Robert H. Lurie Children's Hospital of Chicago
Chicago, Illinois, 60611
- Recruiting
University of Chicago Medical Center
Chicago, Illinois, 60637
- Active, not recruiting
University Hospitals Cleveland Medical Center
Cleveland, Ohio, 44106
- Not yet recruiting
Advanced Specialty Care
Commack, New York, 11725
- Not yet recruiting
Stony Brook Medicine Clinical Research Center
East Setauket, New York, 11733
- Not yet recruiting
Texas Children's Hospital
Houston, Texas, 77030
- Active, not recruiting
Children's Hospital Los Angeles
Los Angeles, California, 90027
- Active, not recruiting
Kaiser Permanente
Los Angeles, California, 90027
- Not yet recruiting
UCLA David Geffen School of Medicine
Los Angeles, California, 90095
- Not yet recruiting
UCLA
Los Angeles, California, 90095
- Active, not recruiting
UH Landerbrook Health Center
Mayfield Heights, Ohio, 44124
- Terminated
Biopharma Informatic, LLC
McAllen, Texas, 78503
- Recruiting
Life Spring Research Foundation
Miami, Florida, 33130
- Not yet recruiting
Childrens Hospitals and Clinics of Minnesota
Minneapolis, Minnesota, 55404
- Not yet recruiting
Cohen Children's Medical Center
New Hyde Park, New York, 11040
- Not yet recruiting
Columbia University Irving Medical Center
New York, New York, 10032
- Terminated
Children's Hospital & Medical Center
Omaha, Nebraska, 68114
- Active, not recruiting
UH Parma Medical Center
Parma, Ohio, 44129
- Active, not recruiting
Phoenix Children's Hospital
Phoenix, Arizona, 85016
- Not yet recruiting
Children's Hospital of Pittsburgh
Pittsburgh, Pennsylvania, 15213
- Active, not recruiting
Rhode Island Hospital
Providence, Rhode Island, 02903
- Active, not recruiting
The Miriam Hospital-Clinical Trials
Providence, Rhode Island, 02904
- Terminated
UNC Children's Raleigh
Raleigh, North Carolina, 27607
- Active, not recruiting
SKY Integrative Medical Center/SKYCRNG
Ridgeland, Mississippi, 39157
- Not yet recruiting
University of Utah
Salt Lake City, Utah, 84108
- Recruiting
Consano Clinical Research, LLC
Shavano Park, Texas, 78231
- Recruiting
Louisiana State University Health Sciences Shreveport
Shreveport, Louisiana, 71101
- Terminated
Avera McKennan Hospital & University Health Center
Sioux Falls, South Dakota, 57105
- Terminated
Avera Research Institute - Sioux Falls
Sioux Falls, South Dakota, 57108
- Not yet recruiting
St. Louis Children's Hospital
St Louis, Missouri, 63110
- Not yet recruiting
Washington University School of Medicine
St Louis, Missouri, 63110
- Not yet recruiting
Stony Brook University
Stony Brook, New York, 11794
- Not yet recruiting
Upstate Health Care Center
Syracuse, New York, 13202
- Not yet recruiting
Crouse Physicians Office Building
Syracuse, New York, 13210
- Not yet recruiting
SUNY Upstate Medical University
Syracuse, New York, 13210
- Not yet recruiting
Upstate Golisano Children's Hospital
Syracuse, New York, 13210
- Terminated
Rophe Adult and Pediatric Medicine/SKYCRNG
Union City, Georgia, 30291
- Active, not recruiting
Children's National Medical Center
Washington D.C., District of Columbia, 20010
- Terminated
University of Massachusetts Chan Medical School
Worcester, Massachusetts, 01655
Mexico11 sites, 2 recruiting
- Not yet recruiting
Centenario Hospital Miguel Hidalgo
Aguascalientes, 20259
- Active, not recruiting
JM Research SC
Cuernavaca, Morelos, 62290
- Active, not recruiting
Unidad de Atención Médica e Investigación en Salud
Mérida, Yucatán, 97000
- Active, not recruiting
Kohler & Milstein Research S.A. De C.V.
Mérida, Yucatán, 97070
- Active, not recruiting
Centro Multidisciplinario para el Desarrollo Especializado de la Investigacion Clinica en Yucatán S.
Mérida, Yucatán, 97130
- Not yet recruiting
Instituto Nacional de Pediatria
Mexico City, Mexico City, 04530
- Active, not recruiting
Hospital Infantil de Mexico Federico Gomez
Mexico City, Mexico City, 06720
- Active, not recruiting
Fundación Santos y De la Garza Evia
Monterrey, Nuevo León, 64710
- Terminated
Eukarya Pharmasite S.C.
Monterrey, Nuevo León, 64718
- Active, not recruiting
Arké SMO S.A de C.V
Veracruz, 91900
- Active, not recruiting
Sociedad de Metabolismo y Corazon S.C.
Veracruz, C.P. 91900
Bulgaria5 sites, 4 recruiting
- Not yet recruiting
МHAT "Sveti Ivan Rilski" Gorna Oryahovitsa
Gorna Oryahovitsa, 5100
- Not yet recruiting
"Specialized Hospital for Active Treatment of Pneumo-Physiatric Diseases Dr. Dimitar Gramatikov -
Rousse, 7002
- Not yet recruiting
Medical Center-1-Sevlievo EOOD
Sevlievo, 5400
- Terminated
DCC "Alexandrovska"
Sofia, 1431
- Not yet recruiting
Specialized Hospital for Active Treatment of Pneumo-Phthisiatric Diseases Vratsa EOOD
Vratsa, 3000
South Africa3 sites, 1 recruiting
- Active, not recruiting
Worthwhile Clinical Trials
Benoni, Gauteng, 1500
- Active, not recruiting
CRISMO Research Centre
Germiston, Gauteng, 1401
- Not yet recruiting
Botho Ke Bontle Health Services
Pretoria, Gauteng, 0184
Japan2 sites, 2 recruiting
- Not yet recruiting
Tokyo Metropolitan Children's Medical Center
Fuchū, Tokyo, 183-8561
- Not yet recruiting
Osaka City General Hospital
Osaka, 534-0021
Puerto Rico1 site, 1 recruiting
- Not yet recruiting
San Miguel Medical
Trujillo Alto, 00976
United Kingdom1 site
- Active, not recruiting
St. George's Hospital
London, England, SW17 0QT
About this study
Official title: A PHASE 2/3, INTERVENTIONAL SAFETY, PHARMACOKINETICS, AND EFFICACY, OPEN-LABEL, MULTI-CENTER, SINGLE-ARM STUDY TO INVESTIGATE ORALLY ADMINISTERED PF-07321332 (NIRMATRELVIR)/RITONAVIR IN NONHOSPITALIZED SYMPTOMATIC PEDIATRIC PARTICIPANTS WITH COVID-19 WHO ARE AT RISK OF PROGRESSION TO SEVERE DISEASE
The purpose of this clinical trial is to learn about the safety, pharmacokinetics (pharmacokinetics helps us understand how the drug is changed and eliminated from your body after you take it), and efficacy (how well a study treatment works in the study) of the study medicine (called nirmatrelvir/ritonavir) for potential treatment of coronavirus disease 2019 (COVID-19).
The study medicine will be given to patients under 18 years of age with COVID-19 that are not hospitalized but are at risk for severe disease.
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
nirmatrelvirDrug
PF-07321332
ritonavirDrug
ritonavir
| Study group | Role | What they receive |
|---|---|---|
| Cohort 1 nirmatrelvir/ritonavir | Experimental | nirmatrelvir/ritonavir will be given by tablets or powder by mouth twice a day for 5 days (10 doses total).
Weight ≥40 kg
1. ≥12 to <18 years
2. ≥6 to <12 years Receives: Drug: nirmatrelvir; Drug: ritonavir |
| Cohort 2 nirmatrelvir/ritonavir | Experimental | nirmatrelvir/ritonavir will be given as powder by mouth twice a day for 5 days (10 doses total) Weight ≥20 to <40 kg, ≥6 to <18 years Receives: Drug: nirmatrelvir; Drug: ritonavir |
| Cohort 3 nirmatrelvir/ritonavir | Experimental | nirmatrelvir/ritonavir
≥2 to <6 years Receives: Drug: nirmatrelvir; Drug: ritonavir |
| Cohort 4 nirmatrelvir/ritonavir | Experimental | nirmatrelvir/ritonavir
≥1 month (≥28 days) to <2 years Receives: Drug: nirmatrelvir; Drug: ritonavir |
| Cohort 5 nirmatrelvir/ritonavir | Experimental | nirmatrelvir/ritonavir <1 month (<28 days) old Receives: Drug: nirmatrelvir; Drug: ritonavir |
What is being measured
The primary outcome is the main question the study is designed to answer.
Cohort 1-2: Maximum Observed Plasma Concentration (Cmax) of nirmatrelvir and ritonavir
Measured: Day 1: 1 hour-post dose; Day 4: pre-dose; Day 5: pre-dose, and 1, and 2 hours post dose
Cohort 1-2: Area Under the Curve to the End of the Dosing Period (AUC0-tau) of nirmatrelvir and ritonavir
Measured: Day 1: 1 hour-post dose; Day 4: pre-dose; Day 5: pre-dose, and 1, and 2 hours post dose
Incidence of Treatment Emergent Adverse Events (TEAEs) leading to discontinuations.
Measured: From Baseline up through Day 34
Incidence of Serious Adverse Events (SAEs) leading to discontinuations.
Measured: From Baseline up through Day 34
Incidence of Adverse Events (AEs) leading to discontinuations.
Measured: From Baseline up through Day 34
Number of participants with change from Baseline in Vital Signs
Measured: From Baseline up through Day 34
Secondary outcomes (3)
Viral load assessment titers measured via reverse transcription polymerase chain reaction (RT-PCR) in nasopharyngeal or nasal swabs over time
Measured: Baseline, Day 5, 6, 10, 14 and 28
Proportion of participants with COVID-19 related hospitalization or death from any cause
Measured: From Baseline through Day 28
Patient assessment on acceptability and palatability of nirmatrelvir/ritonavir (film-coated tablets and oral powder)
Frequency of responses to visual questionnaire on taste.
Measured: At baseline only for tablets and after each dose for powder formulation
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted2 Mar 2022
- Study start7 Mar 2022
- Primary completion30 Jul 2026 (estimated)
- Study completion30 Jul 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for COVID-19Studies of the same condition, open and under way.
- More trials run by PfizerThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 160 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Pfizer
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Pfizer CT.gov Call Center, Study director, Pfizer
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05261139
- Sponsor's protocol ID
- C4671026
- Other IDs
- 2023-509773-23-00, 2023
- Status last verified
- Jul 2025
- First submitted
- 25 Feb 2022
- Last updated
- 17 Jul 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Yes: Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical\_trials/trial\_data\_and\_results/data\_requests.
Study at a glance
From the registry record, last updated by the sponsor on 17 Jul 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A PHASE 2/3, INTERVENTIONAL SAFETY, PHARMACOKINETICS, AND EFFICACY, OPEN-LABEL, MULTI-CENTER, SINGLE-ARM STUDY TO INVESTIGATE ORALLY ADMINISTERED PF-07321332 (NIRMATRELVIR)/RITONAVIR IN NONHOSPITALIZED SYMPTOMATIC PEDIATRIC PARTICIPANTS WITH COVID-19 WHO ARE AT RISK OF PROGRESSION TO SEVERE DISEASE
- ClinicalTrials.gov ID
- NCT05261139
- Acronym / sponsor ID
- C4671026
- Conditions
- COVID-19
- Keywords
- Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2), Pediatrics
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 160 participants (estimated)
- Lead sponsor
- PfizerIndustry (pharma, biotech, devices)
- Study start
- 7 Mar 2022 (actual)
- Primary completion
- 30 Jul 2026 (estimated)
- Study completion
- 30 Jul 2026 (estimated)
- First posted
- 2 Mar 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this clinical trial is to learn about the safety, pharmacokinetics (pharmacokinetics helps us understand how the drug is changed and eliminated from your body after you take it), and efficacy (how well a study treatment works in the study) of the study medicine (called nirmatrelvir/ritonavir) for potential treatment of coronavirus disease 2019 (COVID-19).
The study medicine will be given to patients under 18 years of age with COVID-19 that are not hospitalized but are at risk for severe disease.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 5
| Arm | Type | Receives |
|---|---|---|
| Cohort 1 nirmatrelvir/ritonavir | Experimental | Drug: nirmatrelvir, Drug: ritonavirnirmatrelvir/ritonavir will be given by tablets or powder by mouth twice a day for 5 days (10 doses total). Weight ≥40 kg 1. ≥12 to <18 years 2. ≥6 to <12 years |
| Cohort 2 nirmatrelvir/ritonavir | Experimental | Drug: nirmatrelvir, Drug: ritonavirnirmatrelvir/ritonavir will be given as powder by mouth twice a day for 5 days (10 doses total) Weight ≥20 to <40 kg, ≥6 to <18 years |
| Cohort 3 nirmatrelvir/ritonavir | Experimental | Drug: nirmatrelvir, Drug: ritonavirnirmatrelvir/ritonavir ≥2 to <6 years |
| Cohort 4 nirmatrelvir/ritonavir | Experimental | Drug: nirmatrelvir, Drug: ritonavirnirmatrelvir/ritonavir ≥1 month (≥28 days) to <2 years |
| Cohort 5 nirmatrelvir/ritonavir | Experimental | Drug: nirmatrelvir, Drug: ritonavirnirmatrelvir/ritonavir <1 month (<28 days) old |
Who may qualify
- Ages
- 0 to 17 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child
Key inclusion criteria (4 listed)
- Male and female, age 0 to < 18 years, able to swallow for some participants
- Confirmed SARS-CoV-2 infection within 72 hours prior to enrollment
- Initial onset of COVID-19 signs/symptoms within 5 days prior to the day of enrollment and at least 1 of the specified COVID-19 signs/symptoms present at enrollment
- Has at least 1 characteristic or underlying medical condition associated with an increased risk of developing severe illness from COVID-19
Key exclusion criteria (9 listed)
- History of or need for hospitalization for the medical treatment of COVID-19
- Total bilirubin >=2X upper limit of normal (ULN) (except for Gilbert's syndrome)
- Receiving dialysis or have known moderate to severe renal impairment
- Suspected or confirmed concurrent active systemic infection other than COVID-19
- History of hypersensitivity or other contraindication to any of the components of the study intervention
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| nirmatrelvirPF-07321332 | Drug | Cohort 1 nirmatrelvir/ritonavir, Cohort 2 nirmatrelvir/ritonavir, Cohort 3 nirmatrelvir/ritonavir, Cohort 4 nirmatrelvir/ritonavir, Cohort 5 nirmatrelvir/ritonavir |
| ritonavirritonavir | Drug | Cohort 1 nirmatrelvir/ritonavir, Cohort 2 nirmatrelvir/ritonavir, Cohort 3 nirmatrelvir/ritonavir, Cohort 4 nirmatrelvir/ritonavir, Cohort 5 nirmatrelvir/ritonavir |
Primary outcome
Cohort 1-2: Maximum Observed Plasma Concentration (Cmax) of nirmatrelvir and ritonavir
Time frame: Day 1: 1 hour-post dose; Day 4: pre-dose; Day 5: pre-dose, and 1, and 2 hours post dose
Cohort 1-2: Area Under the Curve to the End of the Dosing Period (AUC0-tau) of nirmatrelvir and ritonavir
Time frame: Day 1: 1 hour-post dose; Day 4: pre-dose; Day 5: pre-dose, and 1, and 2 hours post dose
Incidence of Treatment Emergent Adverse Events (TEAEs) leading to discontinuations.
Time frame: From Baseline up through Day 34
Incidence of Serious Adverse Events (SAEs) leading to discontinuations.
Time frame: From Baseline up through Day 34
Incidence of Adverse Events (AEs) leading to discontinuations.
Time frame: From Baseline up through Day 34
Number of participants with change from Baseline in Vital Signs
Time frame: From Baseline up through Day 34
3 secondary outcomes
Viral load assessment titers measured via reverse transcription polymerase chain reaction (RT-PCR) in nasopharyngeal or nasal swabs over time
Time frame: Baseline, Day 5, 6, 10, 14 and 28
Proportion of participants with COVID-19 related hospitalization or death from any cause
Time frame: From Baseline through Day 28
Patient assessment on acceptability and palatability of nirmatrelvir/ritonavir (film-coated tablets and oral powder)
Time frame: At baseline only for tablets and after each dose for powder formulation
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 17 Jul 2025.
- To obtain contact information for a study center near you, click here.Link provided by the sponsor.
- Individual participant dataSharing planned: Yes. Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Pfizer CT.gov Call Center study director
Pfizer
73 sites in 7 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing nirmatrelvir and ritonavir in people with COVID-19, run by Pfizer at 73 sites in 7 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 17 Jul 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 73 sites in United States, Mexico, Bulgaria, South Africa, Japan and 2 more countries. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Pfizer CT.gov Call Center (1-800-718-1021, ClinicalTrials.gov_Inquiries@pfizer.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Cohort 1-2: Maximum Observed Plasma Concentration (Cmax) of nirmatrelvir and ritonavir (time frame: Day 1: 1 hour-post dose; Day 4: pre-dose; Day 5: pre-dose, and 1, and 2 hours post dose). The study lists 6 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 17 Jul 2025.