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Evaluation of Protease Inhibition for COVID-19 in Standard-Risk Patients (EPIC-SR).

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
ClinicalTrials.gov Identifier: NCT05011513
Recruitment Status : Terminated (Enrollment ceased due to a very low rate of hospitalization or death observed in the standard-risk patient population)
First Posted : August 18, 2021
Last Update Posted : December 12, 2022
Information provided by (Responsible Party):

Brief Summary:
The primary hypothesis to be tested is whether or not there is a difference in time to sustained alleviation of all targeted COVID-19 signs and symptoms through Day 28 between PF-07321332/ritonavir and placebo.

Condition or disease Intervention/treatment Phase
COVID-19 Drug: PF-07321332 Drug: Ritonavir Drug: Placebo Phase 3

Detailed Description:
Throughout the study period, provision will be made to allow study visits to be conducted at a participant's home or at another non-clinic location, if available. The total study duration is up to 24 weeks.

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 1411 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)
Masking Description: Double-blind
Primary Purpose: Treatment
Actual Study Start Date : August 25, 2021
Actual Primary Completion Date : July 25, 2022
Actual Study Completion Date : July 25, 2022

Resource links provided by the National Library of Medicine

Drug Information available for: Ritonavir

Arm Intervention/treatment
Experimental: PF-07321332/ritonavir
Orally administered PF-07321332+ritonavir
Drug: PF-07321332
PF-07321332 (tablet)

Drug: Ritonavir
Ritonavir (capsule)

Placebo Comparator: Placebo
Orally administered Placebo
Drug: Placebo
Placebo (tablet)

Drug: Placebo
Placebo (capsule)

Primary Outcome Measures :
  1. Time to Sustained Alleviation of All Targeted COVID-19 Signs/Symptoms [ Time Frame: Baseline through Day 28 ]
    Analysis set includes COVID-19 symptom onset 1-3 days before treatment.

Secondary Outcome Measures :
  1. Percentage of Participants Who Experience Adverse Events (AEs) [ Time Frame: Baseline through Day 34 ]
  2. Percentage of Participants Who Experience an AE(s) or Serious Adverse Events (SAEs) that Leads to Study Discontinuation [ Time Frame: Baseline through Day 34 ]
  3. Proportion of Participants With Severe Signs/Symptoms Attributed to COVID-19 [ Time Frame: Baseline through Day 28 ]
  4. Time to Sustained Resolution of All Targeted COVID-19 Signs/Symptoms [ Time Frame: Baseline through Day 28 ]
  5. Duration of Each Targeted COVID-19 Sign/Symptom [ Time Frame: Baseline through Day 28 ]
  6. Proportion of Participants Progressing to a Worsening Status In 1 or More COVID-19 Signs/Symptoms [ Time Frame: Baseline through Day 28 ]
  7. Proportion of Participants With a Resting Peripheral Oxygen Saturation ≥95% [ Time Frame: Days 1, 5 ]
  8. Number of COVID-19 Related Medical Visits [ Time Frame: Baseline through Day 28 ]
  9. Number of Days in Hospital and Intensive Care Unit (ICU) Stay in Participants With COVID-19 Related Hospitalization [ Time Frame: Baseline through Day 28 ]
  10. Proportion of Participants With COVID-19 Related Hospitalization or Death From Any Cause [ Time Frame: Baseline through Day 28 ]
  11. Proportion of Participants With Death (all cause) [ Time Frame: Baseline through Week 24 ]
  12. Minimal Concentration (Ctrough) of PF-07321332 [ Time Frame: Baseline through Day 5 ]
  13. Viral Titers Measured Via Reverse Transcription Polymerase Chain Reaction (RT-PCR) in Nasal Swabs [ Time Frame: Baseline through Day 14 ]
  14. Time to Sustained Alleviation of All Targeted COVID-19 Signs/Symptoms [ Time Frame: Baseline through Day 28 ]
    Analysis set includes COVID-19 symptom onset 1-5 days before treatment.

Information from the National Library of Medicine

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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 5 days prior to randomization
  • Initial onset of COVID-19 signs/symptoms within 5 days of randomization
  • Fertile participants must agree to use a highly effective method of contraception

Exclusion Criteria:

  • Has at least one underlying medical condition associated with an increased risk of developing severe illness from COVID-19
  • History of or need for hospitalization for the medical treatment of COVID-19
  • Prior diagnosis of SARS-CoV-2 infection (reinfection)
  • Known medical history of liver disease
  • Receiving dialysis or have known renal impairment
  • Known Human Immunodeficiency Virus (HIV) infection with viral load > 400 copies/ml or taking prohibited medications for HIV treatment
  • Suspected or confirmed concurrent active systemic infection other than COVID-19
  • Current or expected use of any medications or substances that are highly dependent on Cytochrome P450 3A4 (CYP3A4) for clearance or are strong inducers of CYP3A4
  • Has received or is expected to receive monoclonal antibody treatment or convalescent COVID-19 plasma
  • Has received any SARS-CoV-2 vaccine within 12 months of screening
  • Participating in another interventional clinical study with an investigational compound or device, including those for COVID-19
  • Known prior participation in this trial or other trial involving PF-07321332
  • Oxygen saturation of < 92% on room air
  • Females who are pregnant or breastfeeding

Information from the National Library of Medicine

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): NCT05011513

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Sponsors and Collaborators
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Study Director: Pfizer CT.gov Call Center Pfizer
Additional Information:
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Responsible Party: Pfizer
ClinicalTrials.gov Identifier: NCT05011513    
Other Study ID Numbers: C4671002
2021-002857-28 ( EudraCT Number )
EPIC-SR ( Other Identifier: Alias Study Number )
First Posted: August 18, 2021    Key Record Dates
Last Update Posted: December 12, 2022
Last Verified: December 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

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Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Pfizer:
SARS-CoV-2 Infection
Additional relevant MeSH terms:
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Respiratory Tract Infections
Pneumonia, Viral
Virus Diseases
Coronavirus Infections
Coronaviridae Infections
Nidovirales Infections
RNA Virus Infections
Lung Diseases
Respiratory Tract Diseases
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