EPIC-HR: Study of Oral PF-07321332/Ritonavir Compared With Placebo in Nonhospitalized High Risk Adults With COVID-19
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ClinicalTrials.gov Identifier: NCT04960202 |
Recruitment Status :
Completed
First Posted : July 13, 2021
Last Update Posted : October 25, 2022
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
COVID-19 | Drug: PF-07321332 Drug: Ritonavir Drug: Placebo | Phase 2 Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 2245 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Intervention Model Description: | 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). |
Masking: | Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor) |
Primary Purpose: | Treatment |
Official Title: | AN INTERVENTIONAL EFFICACY AND SAFETY, PHASE 2/3, DOUBLE-BLIND, 2-ARM STUDY TO INVESTIGATE ORALLY ADMINISTERED PF-07321332/RITONAVIR COMPARED WITH PLACEBO IN NONHOSPITALIZED SYMPTOMATIC ADULT PARTICIPANTS WITH COVID-19 WHO ARE AT INCREASED RISK OF PROGRESSING TO SEVERE ILLNESS |
Actual Study Start Date : | July 16, 2021 |
Actual Primary Completion Date : | December 9, 2021 |
Actual Study Completion Date : | April 25, 2022 |

Arm | Intervention/treatment |
---|---|
Experimental: PF-07321332/ritonavir
Orally administered PF-07321332+ritonavir
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Drug: PF-07321332
PF-07321332 (tablet) Drug: Ritonavir Ritonavir (capsule) |
Placebo Comparator: Placebo
Orally administered placebo
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Drug: Placebo
Placebo (tablet or capsule) |
- Proportion of participants with COVID-19 related hospitalization or death from any cause [ Time Frame: Day 1 through Day 28 ]
- Incidence of Adverse Events (AEs) and Serious Adverse Events (SAEs)of PF-07321332/ritonavir relative to placebo [ Time Frame: Day 1 through Day 34 ]
- Incidence of Treatment-emergent Adverse Events (TEAEs) of PF-07321332/ritonavir relative to placebo of PF-07321332/ritonavir relative to placebo [ Time Frame: Day 1 through Day 34 ]
- Duration of each targeted COVID-19 sign/symptom [ Time Frame: Day 1 through Day 28 ]
- Severity of each targeted COVID-19 sign/symptom [ Time Frame: Day 1 through Day 28 ]
- Proportion of participants with death (all cause) [ Time Frame: Day 1 through Week 24 ]
- Plasma Concentration in whole blood of PF-07321332 in nonhospitalized symptomatic adult participants with COVID 19 who are at increased risk of progression to severe disease [ Time Frame: Day 1: 30-90 minutes postdose, and Day 5: predose ]
- Viral titers measured by Reverse Transcription Polymerase Chain Reaction (RT-PCR) in nasal swabs [ Time Frame: Day 1 through Day 14 ]
- Number of COVID-19 related medical visits other than hospitalization [ Time Frame: Day 1 through Day 34 ]
- Number of days in hospital and intensive care unit for the treatment of COVID-19 [ Time Frame: Day 1 through Day 34 ]

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
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

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04960202

Study Director: | Pfizer CT.gov Call Center | Pfizer |
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: | Pfizer |
ClinicalTrials.gov Identifier: | NCT04960202 |
Other Study ID Numbers: |
C4671005 2021-002895-38 ( EudraCT Number ) EPIC-HR ( Other Identifier: Alias Study Number ) |
First Posted: | July 13, 2021 Key Record Dates |
Last Update Posted: | October 25, 2022 |
Last Verified: | October 2022 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Yes |
Plan Description: | 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. |
URL: | https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) |
COVID-19 Respiratory Tract Infections Infections Pneumonia, Viral Pneumonia Virus Diseases Coronavirus Infections Coronaviridae Infections Nidovirales Infections RNA Virus Infections Lung Diseases Respiratory Tract Diseases |
Ritonavir HIV Protease Inhibitors Viral Protease Inhibitors Protease Inhibitors Enzyme Inhibitors Molecular Mechanisms of Pharmacological Action Anti-HIV Agents Anti-Retroviral Agents Antiviral Agents Anti-Infective Agents Cytochrome P-450 CYP3A Inhibitors Cytochrome P-450 Enzyme Inhibitors |