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EPIC-HR: Study of Oral PF-073...

EPIC-HR: Study of Oral PF-07321332/Ritonavir Compared With Placebo in Nonhospitalized High Risk Adults With COVID-19

Last Updated: 2025-07-10

Study Results

Results available

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Basic Information

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Recruitment Status

COMPLETED

Clinical Phase

PHASE2/PHASE3

Total Enrollment

2091 participants

Study Classification

INTERVENTIONAL

Study Start Date

2021-07-16

Study Completion Date

2022-04-25

Brief Summary

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The purpose of this study is to determine whether PF-07321332/ritonavir is safe and effective for the treatment of adults who are ill with COVID-19 and do not need to be in the hospital, but are at an increased risk of developing severe illness. Throughout the study period, provision will be made to allow study visits to be conducted at a participant's home or another non-clinic location if available. The total study duration is up to 24 weeks.

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Detailed Description

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Conditions

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COVID-19

Study Design

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Allocation Method

RANDOMIZED

Intervention Model

PARALLEL

Eligible participants with a confirmed diagnosis of SARS-CoV-2 infection will be randomized (1:1) to receive PF-07321332/ritonavir or placebo orally every 12 hours for 5 days (10 doses total).

Primary Study Purpose

TREATMENT

Blinding Strategy

QUADRUPLE

Participants Caregivers Investigators Outcome Assessors

Study Groups

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PF-07321332/ritonavir

Orally administered PF-07321332+ritonavir

Group Type EXPERIMENTAL

PF-07321332

Intervention Type DRUG

PF-07321332 (tablet)

Ritonavir

Intervention Type DRUG

Ritonavir (capsule)

Placebo

Orally administered placebo

Group Type PLACEBO_COMPARATOR

Placebo

Intervention Type DRUG

Placebo (tablet or capsule)

Interventions

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PF-07321332

PF-07321332 (tablet)

Intervention Type DRUG

Ritonavir

Ritonavir (capsule)

Intervention Type DRUG

Placebo

Placebo (tablet or capsule)

Intervention Type DRUG

Eligibility Criteria

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Inclusion Criteria

* Confirmed SARS-CoV-2 infection within 5 days prior to randomization
* Initial onset of COVID-19 signs/symptoms within 5 days prior to the day of randomization and at least 1 of the specified COVID-19 signs/symptoms present on the day of randomization
* Fertile participants must agree to use a highly effective method of contraception
* Has at least 1 characteristic or underlying medical condition associated with an increased risk of developing severe illness from COVID-19

Exclusion Criteria

* History of or need for hospitalization for the medical treatment of COVID-19
* Prior to current disease episode, any confirmed SARS-CoV-2 infection
* Known medical history of active liver disease
* Receiving dialysis or have known moderate to severe renal impairment
* Known human immunodeficiency virus (HIV) infection with a viral load greater than 400 copies/mL or taking prohibited medications for HIV treatment
* 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 are strong inducers of CYP3A4
* Has received or is expected to receive convalescent COVID-19 plasma
* Has received or is expected to receive any dose of a SARS-CoV-2 vaccine before the Day 34 visit
* Participating in another interventional clinical study with an investigational compound or device, including those for COVID-19 through the long-term follow-up visit
* Known prior participation in this trial or other trial involving PF-07321332
* Oxygen saturation of \<92% on room air, or on their standard home oxygen supplementation for those who regularly receive chronic supplementary oxygen for an underlying lung condition
* Females who are pregnant or breastfeeding

Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

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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Cahaba Research Inc

Pelham, Alabama, United States

Site Status

The Institute for Liver Health dba Arizona Clinical Trials

Mesa, Arizona, United States

Site Status

The Institute for Liver Health dba Arizona Clinical Trials

Tucson, Arizona, United States

Site Status

Hope Clinical Research

Canoga Park, California, United States

Site Status

Ascada Research

Fullerton, California, United States

Site Status

Atella Clinical Research LLC.

La Palma, California, United States

Site Status

Ark Clinical Research

Long Beach, California, United States

Site Status

American Institute of Research

Los Angeles, California, United States

Site Status

South Bay Clinical Research Institute

Redondo Beach, California, United States

Site Status

Hope Clinical Research (COVID Satellite Site)

West Hills, California, United States

Site Status

Future Innovative Treatments, LLC

Colorado Springs, Colorado, United States

Site Status

Xera Med Research

Boca Raton, Florida, United States

Site Status

MOORE Clinical Research, Inc.

Brandon, Florida, United States

Site Status

Innovative Research of West Florida, Inc.

Clearwater, Florida, United States

Site Status

Herco Medical and Research Center Inc

Coral Gables, Florida, United States

Site Status

Advance Clinical Research Group

Cutler Bay, Florida, United States

Site Status