A Study to Learn About the Study Medicine (Nirmatrelvir Plus Ritonavir) in Pregnant Women With COVID-19

NCT ID: NCT05386472

Last Updated: 2025-07-29

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

TERMINATED

Clinical Phase

PHASE1

Total Enrollment

25 participants

Study Classification

INTERVENTIONAL

Study Start Date

2022-06-22

Study Completion Date

2025-05-12

Brief Summary

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The purpose of this clinical trial is to learn about how study medicine (Paxlovid, which contains nirmatrelvir and ritonavir) is changed and eliminated from the body, as well as its safety, and the extent to which side effects can be tolerated for treatment of pregnant women with mild or moderate COVID-19 compared to non-pregnant women with mild or moderate COVID-19.

This study is seeking participants who:

* are expecting a healthy baby and are in their second or third trimester pregnancy and have mild or moderate COVID-19
* are not pregnant and have mild or moderate COVID-19.

All participants in this study will take Paxlovid by mouth every 12 hours for 5 days. We will study the experiences of people receiving the study medicine. This will help us decide if the study medicine is safe.

All participants will take part in this study for at least 34 days; pregnant participants will take part until their delivery, so that the study duration may be up to 6 months, depending on their delivery date.

During this time, participants will have 7to 8 visits and, if pregnant, a visit at delivery. Around 2 to 3 visits and the delivery visit will be done in person (at the clinic or at the participant's home). The other 5 visits may be done over the phone, unless in-person visit is necessary as decided by the doctor. Blood samples will be collected on the first 4 to 5 study visits (and at other study visits, if necessary).

Detailed Description

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Conditions

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COVID-19

Study Design

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Allocation Method

NON_RANDOMIZED

Intervention Model

PARALLEL

Primary Study Purpose

TREATMENT

Blinding Strategy

NONE

(Open Label)

Study Groups

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Cohort 1

Pregnant women in their second trimester

Group Type EXPERIMENTAL

nirmatrelvir

Intervention Type DRUG

Nirmatrelvir (tablets) administered by mouth every 12 hours for 5 days (10 doses total)

ritonavir

Intervention Type DRUG

Ritonavir (capsules) administered by mouth every 12 hours for 5 days (10 doses total)

Cohort 2

Pregnant women in their third trimester

Group Type EXPERIMENTAL

nirmatrelvir

Intervention Type DRUG

Nirmatrelvir (tablets) administered by mouth every 12 hours for 5 days (10 doses total)

ritonavir

Intervention Type DRUG

Ritonavir (capsules) administered by mouth every 12 hours for 5 days (10 doses total)

Cohort 3

Non-pregnant women

Group Type EXPERIMENTAL

nirmatrelvir

Intervention Type DRUG

Nirmatrelvir (tablets) administered by mouth every 12 hours for 5 days (10 doses total)

ritonavir

Intervention Type DRUG

Ritonavir (capsules) administered by mouth every 12 hours for 5 days (10 doses total)

Interventions

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nirmatrelvir

Nirmatrelvir (tablets) administered by mouth every 12 hours for 5 days (10 doses total)

Intervention Type DRUG

ritonavir

Ritonavir (capsules) administered by mouth every 12 hours for 5 days (10 doses total)

Intervention Type DRUG

Other Intervention Names

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PF-07321332

Eligibility Criteria

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Inclusion Criteria

* All cohorts: Mild-to-moderate COVID-19 infection confirmed in sample collected ≤5 days prior to enrollment; onset within 5 days prior to enrollment and presence of ≥1 sign/symptom on the day of enrollment.
* Cohorts 1\&2: Expecting single baby; Pregnant in 2nd trimester, 14 0/7 to 27 6/7 weeks of gestational age (Cohort 1) or 3rd trimester, ≥28 0/7 and ≤34 6/7 weeks of gestational age (Cohort 2), by ultrasound.
* All cohorts: Otherwise healthy participants who are determined by medical history, physical examination, and clinical judgment to be appropriate for inclusion in the study

Exclusion Criteria

* All cohorts: Current need for hospitalization or anticipated need for hospitalization in the clinical opinion of the site investigator.
* Cohorts 1\&2: Prior/current major condition or illness of mother/fetus substantially increasing risk of study participation/completion or impacting pregnancy/fetal outcomes in investigator's judgement.
* All cohorts: Current use of any medications that are highly dependent on CYP3A4 for clearance, and which are contraindicated in combination with nirmatrelvir/ritonavir.
* All cohorts: Has received or is expected to receive monoclonal antibody treatment, convalescent COVID-19 plasma, or anti-viral treatment (eg, molnupiravir) for the current SARSCoV-2 infection.
* All cohorts: Participants with moderate to severe kidney impairment
Minimum Eligible Age

18 Years

Maximum Eligible Age

50 Years

Eligible Sex

FEMALE

Accepts Healthy Volunteers

No

Sponsors

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Pfizer

INDUSTRY

Sponsor Role lead

Responsible Party

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Responsibility Role SPONSOR

Principal Investigators

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Pfizer CT.gov Call Center

Role: STUDY_DIRECTOR

Pfizer

Locations

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University of Alabama at Birmingham/Center for Women's Reproductive Health

Birmingham, Alabama, United States

Site Status

Beautiful Minds Clinical Research Center

Cutler Bay, Florida, United States

Site Status

Omega Research Debary

DeBary, Florida, United States

Site Status

Omega Research Orlando

Orlando, Florida, United States

Site Status

Santos Research Center

Tampa, Florida, United States

Site Status

Clinical Research Prime

Idaho Falls, Idaho, United States

Site Status

Boeson Research MSO

Missoula, Montana, United States

Site Status

Origin Health

Missoula, Montana, United States

Site Status

Maximos Ob/Gyn

League City, Texas, United States

Site Status

University of Utah

Salt Lake City, Utah, United States

Site Status

University of Utah

Salt Lake City, Utah, United States

Site Status

University of Utah Clinical Neuroscience Center

Salt Lake City, Utah, United States

Site Status

University of Utah Hospital

Salt Lake City, Utah, United States

Site Status

Countries

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United States

Related Links

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https://pmiform.com/clinical-trial-info-request?StudyID=C4671035

To obtain contact information for a study center near you, click here.

Other Identifiers

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NCT05386472

Identifier Type: REGISTRY

Identifier Source: secondary_id

C4671035

Identifier Type: -

Identifier Source: org_study_id

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