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

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

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.

Study Overview

• Status: Completed
• Conditions: COVID-19
• Intervention / Treatment: Drug: PF-07321332; Drug: Ritonavir; Drug: Placebo

• Study Type: Interventional
• Enrollment (Actual): 2091
• Phase: Phase 2; Phase 3

Contacts and Locations

Study Locations

• Argentina
  • Buenos Aires
    • Zarate, Buenos Aires, Argentina, B2800DGH
      • Instituto de Investigaciones Clínicas Zarate
  • Tucuman
    • San Miguel de Tucuman, Tucuman, Argentina, 4000
      • Hospital De Clínicas Presidente Dr.Nicolas Avellaneda
• Brazil
  • Distrito Federal
    • Brasilia, Distrito Federal, Brazil, 72145-450
      • Chronos Pesquisa Clínica
  • Pernambuco
    • Recife, Pernambuco, Brazil, 52051-380
      • Hospital Agamenon Magalhaes
  • SAO Paulo
    • Jau, SAO Paulo, Brazil, 17201-130
      • CECIP JAÚ - Centro de Estudos Clínicos do Interior Paulista - LTDA
• Bulgaria
  • Burgas, Bulgaria, 8001
    • Individual Practice for Primary Medical Care - IPPMC - Dr. P. Panayotov EOOD
  • Haskovo, Bulgaria, 6300
    • "Specialized Hospital for Active Treatment of Pneumo-Phthisiatric Diseases-Haskovo" Ltd
  • Kozloduy, Bulgaria, 3320
    • MHAT "Sv.Ivan. Rilski'' Kozloduy EOOD
  • Lom, Bulgaria, 3600
    • Diagnostic-Consultative Center I Lom EOOD
  • Lom, Bulgaria, 3600
    • Multiprofile Hospital for Active Treatment- Sveti Nikolay Chudotvoretz EOOD
  • Lovech, Bulgaria, 5500
    • Medical Centre Leo Clinic EOOD
  • Pleven, Bulgaria, 5800
    • MHAT Heart and Brain EAD
  • Plovdiv, Bulgaria, 4000
    • DCC Sveti Georgi EOOD
  • Plovdiv, Bulgaria, 4004
    • MHAT "St. Panteleimon "- Plovdiv
  • Razgrad, Bulgaria, 7200
    • Multiprofile Hospital for Active Treatment Sveti Ivan Rilski - Razgrad AD
  • Ruse, Bulgaria, 7002
    • "Specialized Hospital for Active Treatment of Pneumo-Physiatric Diseases Dr. Dimitar Gramatikov -
  • Ruse, Bulgaria, 7013
    • UMHAT Medica Ruse OOD
  • Samokov, Bulgaria, 2000
    • Multiprofile Hospital for Active Treatment - Samokov EOOD
  • Sevlievo, Bulgaria, 5400
    • Medical Center-1-Sevlievo EOOD
  • Shumen, Bulgaria, 9700
    • Multiprofile Hospital For Active Treatment Shumen AD
  • Sliven, Bulgaria, 8800
    • Multiprofile hospital for active treatment - Sliven to Military Medical Academy
  • Sliven, Bulgaria, 8801
    • MHAT "Dr. Ivan Seliminski" AD, Sliven
  • Sofia, Bulgaria, 1113
    • Diagnostic-Consultative Center XXII- Sofia ЕООD
  • Sofia, Bulgaria, 1618
    • MHAT "St. Sofia" EOOD
  • Stara Zagora, Bulgaria, 6000
    • Specialized hospital for active treatment in pulmonology and phthisiology "Stara Zagora" EOOD
  • Targovishte, Bulgaria, 7700
    • Multiprofile Hospital for Active Treatment Targovishte AD
  • Tsarevo, Bulgaria, 8260
    • Outpatient Clinic for Primary Outpatient Medical Care "Puls" - Dr. Mladen Buchvarov EOOD
  • Varna, Bulgaria, 9020
    • Medical Center Leo Clinic EOOD
  • Vratsa, Bulgaria, 3000
    • Specialized Hospital for Active Treatment of Pneumo-Phthisiatric Diseases Vratsa EOOD
• Colombia
  • Quindio
    • Armenia, Quindio, Colombia, 630004
      • Fundacion Cardiomet Cequin
• Czechia
  • Protivín, Czechia, 398 11
    • Zdravi-fit, s.r.o.
  • Slany, Czechia, 274 01
    • Nemocnice Slaný
• Hungary
  • Bekescsaba, Hungary, 5600
    • Trial Pharma Kft.
  • Debrecen, Hungary, 4031
    • Debreceni Egyetem Klinikai Kozpont Infektologiai Klinika
  • Eger, Hungary, 3300
    • Agria-Study Kft.
  • Gyula, Hungary, 5700
    • Trial Pharma Kft.
  • Nyiregyhaza, Hungary, 4400
    • Medifarma-98 Kft.
• India
  • New Delhi, India, 110075
    • Aakash Healthcare Private Limited
  • Pavan PURI Bikaner, Rajasthan, India, 334003
    • Sardar Patel Medical College
  • Chhattisgarh
    • Raipur, Chhattisgarh, India, 492099
      • AIIMS Raipur
  • Gujarat
    • Vadodara, Gujarat, India, 390012
      • Jupiter Hospital
  • Karnataka
    • Bangalore, Karnataka, India, 560060
      • BGS Global Institute of Medical Sciences and Hospital
  • Kerala
    • Kochi, Kerala, India, 682018
      • Lisie Hospital
  • Maharashtra
    • Pune, Maharashtra, India, 411001
      • Jehangir Clinical Development Centre Pvt. Ltd
    • Pune, Maharashtra, India, 411057
      • Lifepoint Research LLP
  • Rajasthan
    • Ajmer, Rajasthan, India, 305001
      • Jawahar Lal Nehru Medical College
    • Jaipur, Rajasthan, India, 302017
      • Apex Hospitals Pvt Ltd
    • Jaipur, Rajasthan, India, 302039
      • Maharaja Agrasen Superspeciality Hospital
  • WEST Bengal
    • Kolkata, WEST Bengal, India, 700014
      • Nil Ratan Sircar Medical College and Hospital
• Japan
  • Chiba
    • Narita, Chiba, Japan, 286-8520
      • International University of Health and Welfare Narita Hospital
  • Hokkaido
    • Sapporo, Hokkaido, Japan, 063-0005
      • National Hokkaido Medical Center
  • Osaka
    • Izumisano, Osaka, Japan, 598-8577
      • Rinku General Medical Center
  • Tokyo
    • Hachioji, Tokyo, Japan, 1930998
      • Tokyo Medical University Hachioji Medical Center
    • Shinjuku City, Tokyo, Japan, 162-8655
      • National Center for Global Health and Medicine
• Korea, Republic of
  • Daegu, Korea, Republic of, 41404
    • Kyungpook National University Chilgok Hospital
  • Incheon, Korea, Republic of, 22532
    • Incheon Medical Center
  • Nam-gu, Korea, Republic of, 61748
    • Chonnam National University Bitgoeul Hospital
  • Seoul, Korea, Republic of, 07061
    • SMG-SNU Boramae Medical Center
• Malaysia
  • Sarawak
    • Kuching, Sarawak, Malaysia, 93586
      • Hospital Umum Sarawak
    • Miri, Sarawak, Malaysia, 98000
      • Hospital Miri
• Mexico
  • Acapulco, Mexico
    • Centro de Investigacion Clinica Del Pacifico SA de CV
  • Aguascalientes, Mexico, CP 201230
    • Hospital Cardiologica Aguascalientes
  • Durango, Mexico, 34000
    • Instituto de Investigaciones Clínicas para la Salud
  • Veracruz, Mexico, 91900
    • Sociedad de Metabolismo y Corazón S.C.
  • Veracruz, Mexico, 91900
    • FAICIC S. de R.L. de C.V.
  • Veracruz, Mexico, 91910
    • Arké SMO S.A de C.V
  • Coahuila
    • Saltillo, Coahuila, Mexico, 25020
      • Clinical Research Institute Saltillo S.A. de C.V.
  • Hidalgo
    • Pachuca de Soto, Hidalgo, Mexico, 42070
      • Asociacion Mexicana para la Investigacion Clinica A.C. (AMIC)
  • Jalisco
    • Guadalajara, Jalisco, Mexico, 44670
      • Instituto Jalisciense de Metabolismo, S.C.
  • Morelos
    • Cuernavaca, Morelos, Mexico, 62290
      • JM Research SC
  • Nuevo LEON
    • Monterrey, Nuevo LEON, Mexico, 64060
      • Christus - Latam Hub Center of Excellence and Innovation Center S.C.
    • Monterrey, Nuevo LEON, Mexico, 64718
      • Eukarya Pharmasite S.C.
  • Oaxaca
    • Oaxaca de Juarez, Oaxaca, Mexico, 68000
      • Oaxaca Site Management Organization
  • Tijuana
    • Baja California, Tijuana, Mexico, 22010
      • InfectoLab Consultorios de Especialidad en Infectologia
  • Yucatan
    • Merida, Yucatan, Mexico, 97070
      • Kohler & Milstein Research S.A. De C.V.
  • Yucatán
    • Mérida, Yucatán, Mexico, 97000
      • Eme Red Hospitalaria
• Poland
  • Bialystok, Poland, 15-704
    • KLIMED Marek Klimkiewicz
  • Wroclaw, Poland, 51-162
    • Centrum Badań Klinicznych Piotr Napora Lekarze Spółka Partnerska
• Puerto Rico
  • Ponce, Puerto Rico, 00780
    • Clinical Research Management Group Inc
  • San Juan, Puerto Rico, 00926
    • Advance Medical Research Center
• Russian Federation
  • Barnaul, Russian Federation, 656045
    • Barnaul City Hospital Number 5
  • Moscow, Russian Federation, 115419
    • KDC "Evromedservis", OJSC
  • Smolensk, Russian Federation, 214019
    • Smolensk State Medical University
  • Moscow Region
    • Odintsovo, Moscow Region, Russian Federation, 143005
      • LLC Trekhgorka Medicine
• South Africa
  • FREE State
    • Welkom, FREE State, South Africa, 9460
      • MERC Welkom
  • Gauteng
    • Benoni, Gauteng, South Africa, 1500
      • East Rand Research Centre T/A Worthwhile Clinical Trials
    • Pretoria, Gauteng, South Africa, 0122
      • Botho ke Bontle Health Services
  • Kwazulu Natal
    • Durban, Kwazulu Natal, South Africa, 4001
      • Synapta Clinical Research Center
  • Limpopo
    • Thabazimbi, Limpopo, South Africa, 0380
      • Limpopo Clinical Research Initiative
  • Mpumalanga
    • Middelburg, Mpumalanga, South Africa, 1055
      • MERC Middelburg
• Spain
  • A Coruña, Spain, 15006
    • Complexo Hospitalario Universitario da Coruna
  • Barcelona [barcelona]
    • Centelles, Barcelona [barcelona], Spain, 08540
      • EBA Centelles
• Thailand
  • Bangkok
    • Bangrak, Bangkok, Thailand, 10500
      • Bangkok Centre Hotel
    • Pathum Wan District,, Bangkok, Thailand, 10330
      • Chula Field Hospital, Chulalongkorn University Sport center (Chantanayingyong Gymnasium)
    • Pathumwan, Bangkok, Thailand, 10330
      • The HIV Netherlands Australia Thailand Research Collaboration (HIV-NAT),
    • Pathumwan,, Bangkok, Thailand, 10330
      • Thai Red Cross Emerging Infectious Diseases (EDI) Clinic
  • Khon Kaen
    • Muang, Khon Kaen, Thailand, 40002
      • Faculty of Medicine - Khon Kaen University
  • Songkhla
    • Hat Yai, Songkhla, Thailand, 90110
      • Department of Internal Medicine, Faculty of Medicine, Prince of Songkla University,
• Turkey
  • Ankara, Turkey, 06230
    • Ankara University Medical Faculty, Ibni-Sina Hospital
  • Ankara, Turkey, 06230
    • Hacettepe University Medical Faculty Hospital
  • Antalya, Turkey, 07059
    • Akdeniz Universitesi Hastanesi
  • Beykoz / Istanbul, Turkey, 34810
    • Istanbul Medipol University Clinical Research Ethics Committee
  • Gaziantep, Turkey, 27300
    • Gaziantep University Medical Faculty
  • Istanbul, Turkey, 34098
    • Istanbul University Cerrahpasa-Cerrahpasa Medical Faculty
  • Istanbul, Turkey, 34480
    • Başakşehir Çam ve Sakura Şehir Hastanesi
  • Istanbul, Turkey, 34020
    • Istanbul Yedikule Gogus Hastaliklari ve Gogus Cerrahisi Egitim Arastirma Hastanesi
  • Istanbul, Turkey, 34303
    • Acibadem Saglik Hizmetleri ve Tic.A.S, Acibadem Atakent Hastanesi
  • Istanbul, Turkey, 34452
    • Istanbul Universitesi Klinik Arastirmalar Mukemmeliyet Uygulama ve Arastirma Merkezi
  • Kocaeli, Turkey, 41380
    • Kocaeli University Medical Faculty
  • Konak/Izmir, Turkey, 35170
    • Sbü Dr. Suat Seren Göğüs Hastaliklari Ve Cerrahisi Eğitim Ve Araştirma Hastanesi
  • Mersin, Turkey, 33110
    • Mersin University Health Research and Application Hospital
  • Sakarya, Turkey, 54100
    • Sakarya University Training and Research Hospital
  • Trabzon, Turkey, 61080
    • Karadeniz Teknik Üniversitesi Farabi Hastanesi
• Ukraine
  • Dnipro, Ukraine, 49069
    • Communal non-profit enterprise "City Clinical Hospital #16" of Dnipro City Council
  • Ivano-Frankivsk, Ukraine, 76007
    • Municipal Nonprofit Enterprise "Ivano-Frankivsk Regional Clinical Infectious Diseases Hospital of
  • Ivano-Frankivsk, Ukraine, 76018
    • Communal nonprofit enterprise "Central City Clinical Hospital of Ivano-Frankivsk City Council"
  • Kharkiv, Ukraine, 61096
    • Municipal Nonprofit Enterprise of Kharkiv Regional Council "Regional Clinical Infectious Diseases
  • Kharkiv, Ukraine, 61002
    • Municipal Nonprofit Enterprise "City Student Hospital" of Kharkiv City Council
  • Kyiv, Ukraine, 02091
    • Municipal non-commercial enterprise "Kyiv City Clinical Hospital #1" Of Executive Body Of the Kyiv
  • Kyiv, Ukraine, 03049
    • Kyiv Railway Clinical Hospital No.2 of Branch "Health Center of the Public Joint Stock Company
  • Kyiv, Ukraine, 04050
    • Polyclinic of Center for Medical Services and Rehabilitation of State Joint-Stock Holding Company
  • Kyiv, Ukraine, 01601
    • "Municipal Non-Profit Enterprise "Alexander Clinical Hospital of Kyiv" of the Kyiv City Council
  • Lviv, Ukraine, 79011
    • Municipal Nonprofit Enterprise "Lviv City Clinic Hospital #4"
  • Lviv, Ukraine, 79008
    • Municipal NonProfit Enterprise of the Lviv Regional Council Lviv Regional Information and Analitical
  • Poltava, Ukraine, 36011
    • Municipal Enterprise "Poltava Regional Clinical Infectious Diseases Hospital" of Poltava Regional
  • Tarasove Village, Ukraine, 45625
    • Municipal Enterprise "Volyn Regional Clinical Hospital" of Volyn Regional Council
  • Vinnytsia, Ukraine, 21029
    • Municipal Non-commercial Enterprise "Vinnytsia City Clinical Hospital №1"
  • Zhytomyr, Ukraine, 10002
    • Communal Enterprise "Hospital #1" of Zhytomyr City Council
• United States
  • Alabama
    • Pelham, Alabama, United States, 35124
      • Cahaba Research Inc
  • Arizona
    • Mesa, Arizona, United States, 85210
      • The Institute for Liver Health dba Arizona Clinical Trials
    • Tucson, Arizona, United States, 85712
      • The Institute for Liver Health dba Arizona Clinical Trials
  • California
    • Canoga Park, California, United States, 91303
      • HOPE Clinical Research
    • Fullerton, California, United States, 92835
      • Ascada Research
    • La Palma, California, United States, 90623
      • Atella Clinical Research LLC.
    • Long Beach, California, United States, 90806
      • Ark Clinical Research
    • Los Angeles, California, United States, 90017
      • American Institute of Research
    • Redondo Beach, California, United States, 90277
      • South Bay Clinical Research Institute
    • West Hills, California, United States, 91304
      • Hope Clinical Research (COVID Satellite Site)
  • Colorado
    • Colorado Springs, Colorado, United States, 80907
      • Future Innovative Treatments, LLC
  • Florida
    • Boca Raton, Florida, United States, 33487
      • Xera Med Research
    • Brandon, Florida, United States, 33511
      • MOORE Clinical Research, Inc.
    • Clearwater, Florida, United States, 33756
      • Innovative Research of West Florida, Inc.
    • Coral Gables, Florida, United States, 33134
      • Herco Medical and Research Center Inc
    • Cutler Bay, Florida, United States, 33157
      • Advance Clinical Research Group
    • Cutler Bay, Florida, United States, 33157
      • Beautiful Minds Clinical Research Center
    • Hialeah, Florida, United States, 33010
      • Qway Research
    • Hialeah, Florida, United States, 33013
      • Eastern Research Inc
    • Hialeah, Florida, United States, 33013
      • Inpatient Research Clinic
    • Hialeah, Florida, United States, 33016
      • Doral Medical Research LLC.
    • Hialeah, Florida, United States, 33016
      • Doral Medical Research,LLC
    • Hialeah Gardens, Florida, United States, 33018
      • Unlimited Medical Research Group, LLC
    • Loxahatchee Groves, Florida, United States, 33470
      • Advanced Pulmonary Research Institute
    • Miami, Florida, United States, 33135
      • Suncoast Research Group, LLC
    • Miami, Florida, United States, 33126
      • LCC Medical Research Institute, LLC
    • Miami, Florida, United States, 33122
      • Angels Clinical Research Institute
    • Miami, Florida, United States, 33126
      • Premium Medical Research Corp
    • Miami, Florida, United States, 33135
      • Global Health Clinical Trials Corp
    • Miami, Florida, United States, 33135
      • South Florida Research Center, Inc.
    • Miami, Florida, United States, 33144
      • I.V.A.M. Clinical & Investigational Center, LLC
    • Miami, Florida, United States, 33174
      • C'A Research
    • Miami, Florida, United States, 33175
      • ProLive Medical Research, Corp.
    • Miami, Florida, United States, 33176
      • Entrust Clinical Research
    • Miami, Florida, United States, 33176
      • Reed Medical Research
    • Miami, Florida, United States, 33186
      • Clinical Site Partners, Inc d/b/a CSP Miami
    • Miami, Florida, United States, 33186
      • Coral Research Clinic Corp
    • Miami, Florida, United States, 33185
      • Kendall South Medical Center
    • Miami Lakes, Florida, United States, 33014
      • Savin Medical Group, LLC
    • Orlando, Florida, United States, 32808
      • Omega Research Orlando, LLC
    • Pompano Beach, Florida, United States, 33064
      • NAPA Research LLC
    • Port Saint Lucie, Florida, United States, 34952
      • CDC Research Institute
    • Saint Petersburg, Florida, United States, 33705
      • GCP, Global Clinical Professionals
    • South Miami, Florida, United States, 33143
      • USPA Advance Concept Medical Research Group LLC
    • Sunrise, Florida, United States, 33325
      • Sunrise Research Institute
    • Tampa, Florida, United States, 33615
      • Santos Research Center, CORP
    • Winter Park, Florida, United States, 32789
      • Clinical Site Partners, Inc. dba CSP Orlando
  • Illinois
    • Chicago, Illinois, United States, 60643
      • Research by Design, LLC
  • Louisiana
    • Marrero, Louisiana, United States, 70072
      • Tandem Clinical Research GI, LLC
    • Marrero, Louisiana, United States, 70072
      • New Orleans Sinus Center (COVID-19 Testing)
  • Montana
    • Butte, Montana, United States, 59701
      • Mercury Street Medical Group, PLLC
  • Nevada
    • Las Vegas, Nevada, United States, 89109
      • Excel Clinical Research
  • New York
    • Endwell, New York, United States, 13760
      • Meridian Clinical Research, LLC
  • North Carolina
    • Monroe, North Carolina, United States, 28112
      • Monroe Biomedical Research
    • Wilmington, North Carolina, United States, 28401
      • Accellacare
  • Tennessee
    • Clarksville, Tennessee, United States, 37040
      • Premier Medical Group
  • Texas
    • Amarillo, Texas, United States, 79109
      • PharmaTex Research, LLC
    • Austin, Texas, United States, 78745
      • ARC Clinical Research at William Cannon
    • Bellaire, Texas, United States, 77401
      • St Hope Foundation
    • Conroe, Texas, United States, 77304
      • Conroe Willis Medical Research
    • Corpus Christi, Texas, United States, 78413
      • South Texas Clinical Research
    • Houston, Texas, United States, 77057
      • Next Level Urgent Care
    • Houston, Texas, United States, 77008
      • SignatureCare Emergency Center
    • Houston, Texas, United States, 77008
      • Trio Clinical Trials, LLC
    • Houston, Texas, United States, 77022
      • C & R Research Services USA
    • Mesquite, Texas, United States, 75149
      • SMS Clinical Research, LLC
    • Mesquite, Texas, United States, 75149
      • SMS Clinical Research
    • Pearland, Texas, United States, 77584
      • LinQ Research, LLC
    • Red Oak, Texas, United States, 75154
      • Epic Medical Research
    • San Antonio, Texas, United States, 78215
      • Sun Research Institute
    • San Antonio, Texas, United States, 78249
      • BFHC Research
    • Webster, Texas, United States, 77598
      • Tranquility Research
  • Virginia
    • Newport News, Virginia, United States, 23606
      • TPMG (Tidewater Physicians Multispecialty Group) Clinical Research

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / 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 or capsule)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of Participants With Covid-19 Related Hospitalization or Death From Any Cause Through Day 28- Modified Intent-To-Treat (mITT) Population	Percentage of participants with COVID-19 related hospitalization or death from any cause during the first 28 days of the study was estimated using the Kaplan-Meier (KM) method. Using KM method, survival probability for each time interval was calculated as the number of participants surviving divided by the number of participants at risk. Participants who had the event, dropped out, or moved out were not counted as "at risk" i.e., participants who were lost were considered "censored" and were not counted in the denominator.	From Day 1 to Day 28

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants With Treatment Emergent Adverse Events (TEAEs)	An adverse event (AE) was any untoward medical occurrence in a participant, temporarily associated with the use of study intervention, whether or not considered related to the study intervention. Serious adverse event (SAE) was any untoward medical occurrence that, at any dose: resulted in death; required inpatient hospitalization or prolongation of existing hospitalization; was life-threatening; resulted in persistent or significant disability/ incapacity; congenital anomaly/birth defect; a suspected transmission via a Pfizer product of an infectious agent, pathogenic or non-pathogenic and other important medical events. AEs included both SAEs and all non-SAEs. An AE was considered as TEAE if the event started on or after start date of study intervention.	From start of study intervention (Day 1) up to end of safety follow-up (Day 34)
Number of Participants With AEs Leading to Discontinuation and Serious Adverse Events (SAEs)	An AE was any untoward medical occurrence in a participant, temporarily associated with the use of study treatment, whether or not considered related to the study treatment. An SAE was any untoward medical occurrence that, at any dose: resulted in death; required inpatient hospitalization or prolongation of existing hospitalization; was life-threatening; resulted in persistent or significant disability/ incapacity; congenital anomaly/birth defect; a suspected transmission via a Pfizer product of an infectious agent, pathogenic or non-pathogenic and other important medical events.	From start of study intervention (Day 1) up to end of safety follow-up (Day 34)
Percentage of Participants With Covid-19 Related Hospitalization or Death From Any Cause Through Day 28- Modified Intent-To-Treat 1 (mITT1) Population	Percentage of participants with COVID-19 related hospitalization or death from any cause during the first 28 days of the study was estimated using the Kaplan-Meier method.	From Day 1 to Day 28
Time to Sustained Alleviation of All Targeted COVID-19 Signs and Symptoms Through Day 28- mITT Population	Sustained alleviation of all targeted COVID-19 signs/symptoms was defined as the event occurring on the first 4 consecutive days when all symptoms scored as moderate or severe at the time of enrollment were scored as mild or absent and those scored mild or absent at the time of enrollment were scored as absent. The first day of the 4 consecutive-day period was considered date of first event. Time to sustained alleviation (event) was calculated as first event date minus first dose date plus 1, for participants with event. For participants who completed Day 28 or discontinued the study before Day 28 without sustained alleviation (censored), time was calculated as censoring date (last date on which symptom alleviation was assessed) minus first dose date plus 1 or Day 25 whichever occurred first.	From Day 1 (baseline) to Day 28
Time to Sustained Alleviation of All Targeted COVID-19 Signs and Symptoms Through Day 28- mITT1 Population	Sustained alleviation of all targeted COVID-19 signs/symptoms was defined as the event occurring on the first 4 consecutive days when all symptoms scored as moderate or severe at the time of enrollment were scored as mild or absent and those scored mild or absent at the time of enrollment were scored as absent. The first day of the 4 consecutive-day period was considered date of first event. Time to sustained alleviation (event) was calculated as first event date minus first dose date plus 1, for participants with event. For participants who completed Day 28 or discontinued the study before Day 28 without sustained alleviation (censored), time was calculated as censoring date (last date on which symptom alleviation was assessed) minus first dose date plus 1 or Day 25 whichever occurred first.	From Day 1 (baseline) to Day 28
Time to Sustained Alleviation of All Targeted COVID-19 Signs and Symptoms Through Day 28- Modified Intent-to-Treat 2 (mITT2) Population	Sustained alleviation of all targeted COVID-19 signs/symptoms was defined as the event occurring on the first 4 consecutive days when all symptoms scored as moderate or severe at the time of enrollment were scored as mild or absent and those scored mild or absent at the time of enrollment were scored as absent. The first day of the 4 consecutive-day period was considered date of first event. Time to sustained alleviation (event) was calculated as first event date minus first dose date plus 1, for participants with event. For participants who completed Day 28 or discontinued the study before Day 28 without sustained alleviation (censored), time was calculated as censoring date (last date on which symptom alleviation was assessed) minus first dose date plus 1 or Day 25 whichever occurred first.	From Day 1 (baseline) to Day 28
Percentage of Participants With Severe Covid-19 Signs and Symptoms Through Day 28- mITT Population	Participants were required to record the severity of their Covid-19 symptoms over the past 24 hours daily on a 4-point scale ranging from 0 to 3, higher scores indicated more severity. The scale was reported as 0= no symptoms, 1=mild, 2=moderate and 3=severe. A participant with severe score for any targeted symptoms post-baseline was counted as severe. Percentage of participants with severe Covid-19 signs and symptoms were reported.	From Day 1 to Day 28
Percentage of Participants With Severe Covid-19 Signs and Symptoms Through Day 28- mITT1 Population	Participants were required to record the severity of their Covid-19 symptoms over the past 24 hours daily on a 4-point scale ranging from 0 to 3, higher scores indicated more severity. The scale was reported as 0= no symptoms, 1=mild, 2=moderate and 3=severe. A participant with severe score for any targeted symptoms post-baseline was counted as severe. Percentage of participants with severe Covid-19 signs and symptoms were reported.	From Day 1 to Day 28
Percentage of Participants With Severe Covid-19 Signs and Symptoms Through Day 28- mITT2 Population	Participants were required to record the severity of their Covid-19 symptoms over the past 24 hours daily on a 4-point scale ranging from 0 to 3, higher scores indicated more severity. The scale was reported as 0= no symptoms, 1=mild, 2=moderate and 3=severe. A participant with severe score for any targeted symptoms post-baseline was counted as severe. Percentage of participants with severe Covid-19 signs and symptoms were reported.	From Day 1 to Day 28
Time to Sustained Resolution of All Targeted COVID-19 Signs and Symptoms Through Day 28- mITT Population	Sustained resolution was defined as when all targeted symptoms were scored as absent for 4 consecutive days. Time to sustained resolution (event) was calculated as first event date minus first dose date plus 1, for participants with event. For participants who completed Day 28 or discontinued the study before Day 28 without sustained resolution (censored), time was calculated as censoring date (last date on which symptom resolution was assessed) minus first dose date plus 1 or Day 25 whichever occurred first.	From Day 1 (baseline) to Day 28
Time to Sustained Resolution of All Targeted COVID-19 Signs and Symptoms Through Day 28- mITT1 Population	Sustained resolution was defined as when all targeted symptoms were scored as absent for 4 consecutive days. Time to sustained resolution (event) was calculated as first event date minus first dose date plus 1, for participants with event. For participants who completed Day 28 or discontinued the study before Day 28 without sustained resolution (censored), time was calculated as censoring date (last date on which symptom resolution was assessed) minus first dose date plus 1 or Day 25 whichever occurred first.	From Day 1 (baseline) to Day 28
Time to Sustained Resolution of All Targeted COVID-19 Signs and Symptoms Through Day 28- mITT2 Population	Sustained resolution was defined as when all targeted symptoms were scored as absent for 4 consecutive days. Time to sustained resolution (event) was calculated as first event date minus first dose date plus 1, for participants with event. For participants who completed Day 28 or discontinued the study before Day 28 without sustained resolution (censored), time was calculated as censoring date (last date on which symptom resolution was assessed) minus first dose date plus 1 or Day 25 whichever occurred first.	From Day 1 (baseline) to Day 28
Time to Sustained Alleviation of Each Targeted COVID-19 Signs and Symptoms- mITT Population	Sustained alleviation of each targeted COVID-19 signs/symptoms was defined as the event occurring on the first 4 consecutive days when each symptom scored as moderate or severe at the time of enrollment were scored as mild or absent and those scored mild or absent at the time of enrollment were scored as absent. The first day of the 4 consecutive-day period was considered date of first event. Time to sustained alleviation (event) was calculated as first event date minus first dose date plus 1, for participants with event. For participants who completed Day 28 or discontinued the study before Day 28 without sustained alleviation (censored), time was calculated as censoring date (last date on which symptom alleviation was assessed) minus first dose date plus 1 or Day 25 whichever occurred first.	From Day 1 (baseline) to Day 28
Time to Sustained Alleviation of Each Targeted COVID-19 Signs and Symptoms- mITT1 Population	Sustained alleviation of each targeted COVID-19 signs/symptoms was defined as the event occurring on the first 4 consecutive days when each symptom scored as moderate or severe at the time of enrollment were scored as mild or absent and those scored mild or absent at the time of enrollment were scored as absent. The first day of the 4 consecutive-day period was considered date of first event. Time to sustained alleviation (event) was calculated as first event date minus first dose date plus 1, for participants with event. For participants who completed Day 28 or discontinued the study before Day 28 without sustained alleviation (censored), time was calculated as censoring date (last date on which symptom alleviation was assessed) minus first dose date plus 1 or Day 25 whichever occurred first.	From Day 1 (baseline) to Day 28
Time to Sustained Alleviation of Each Targeted COVID-19 Signs and Symptoms- mITT2 Population	Sustained alleviation of each targeted COVID-19 signs/symptoms was defined as the event occurring on the first 4 consecutive days when each symptom scored as moderate or severe at the time of enrollment were scored as mild or absent and those scored mild or absent at the time of enrollment were scored as absent. The first day of the 4 consecutive-day period was considered date of first event. Time to sustained alleviation (event) was calculated as first event date minus first dose date plus 1, for participants with event. For participants who completed Day 28 or discontinued the study before Day 28 without sustained alleviation (censored), time was calculated as censoring date (last date on which symptom alleviation was assessed) minus first dose date plus 1 or Day 25 whichever occurred first.	From Day 1 (baseline) to Day 28
Time to Sustained Resolution of Each Targeted COVID-19 Signs and Symptoms- mITT Population	Sustained resolution was defined as when each targeted symptom was scored as absent for 4 consecutive days. Time to sustained resolution (event) was calculated as first event date minus first dose date plus 1, for participants with event. For participants who completed Day 28 or discontinued the study before Day 28 without sustained resolution (censored), time was calculated as censoring date (last date on which symptom resolution was assessed) minus first dose date plus 1 or Day 25 whichever occurred first.	From Day 1 (baseline) to Day 28
Time to Sustained Resolution of Each Targeted COVID-19 Signs and Symptoms- mITT1 Population	Sustained resolution was defined as when each targeted symptom was scored as absent for 4 consecutive days. Time to sustained resolution (event) was calculated as first event date minus first dose date plus 1, for participants with event. For participants who completed Day 28 or discontinued the study before Day 28 without sustained resolution (censored), time was calculated as censoring date (last date on which symptom resolution was assessed) minus first dose date plus 1 or Day 25 whichever occurred first.	From Day 1 (baseline) to Day 28
Time to Sustained Resolution of Each Targeted COVID-19 Signs and Symptoms- mITT2 Population	Sustained resolution was defined as when each targeted symptom was scored as absent for 4 consecutive days. Time to sustained resolution (event) was calculated as first event date minus first dose date plus 1, for participants with event. For participants who completed Day 28 or discontinued the study before Day 28 without sustained resolution (censored), time was calculated as censoring date (last date on which symptom resolution was assessed) minus first dose date plus 1 or Day 25 whichever occurred first.	From Day 1 (baseline) to Day 28
Number of Participants With Progression to a Worsening Status in 1 or More Self-reported COVID-19 Associated Symptoms Through Day 28-mITT Population	Participants were required to record the severity of their Covid-19 symptoms over the past 24 hours daily on a 4-point scale where 0 = no symptoms; 1= mild; 2= moderate; and 3= severe. Vomiting and diarrhea were each rated on a 4-point frequency scale where 0= no occurrence, 1= mild for 1 to 2 times, 2= moderate for 3 to 4 times, and 3= severe for 5 or greater. Progression to a worsening status for any targeted symptom was based up on increasing severity (i.e. the first time any targeted symptoms worsened after treatment relative to baseline).	From Day 1 (baseline) to Day 28
Number of Participants With Progression to a Worsening Status in 1 or More Self-reported COVID-19 Associated Symptoms Through Day 28-mITT1 Population	Participants were required to record the severity of their Covid-19 symptoms over the past 24 hours daily on a 4-point scale where 0 = no symptoms; 1= mild; 2= moderate; and 3= severe. Vomiting and diarrhea were each rated on a 4-point frequency scale where 0= no occurrence, 1= mild for 1 to 2 times, 2= moderate for 3 to 4 times, and 3= severe for 5 or greater. Progression to a worsening status for any targeted symptom was based up on increasing severity (i.e. the first time any targeted symptoms worsened after treatment relative to baseline).	From Day 1 (baseline) to Day 28
Number of Participants With Progression to a Worsening Status in 1 or More Self-reported COVID-19 Associated Symptoms Through Day 28-mITT2 Population	Participants were required to record the severity of their Covid-19 symptoms over the past 24 hours daily on a 4-point scale where 0 = no symptoms; 1= mild; 2= moderate; and 3= severe. Vomiting and diarrhea were each rated on a 4-point frequency scale where 0= no occurrence, 1= mild for 1 to 2 times, 2= moderate for 3 to 4 times, and 3= severe for 5 or greater. Progression to a worsening status for any targeted symptom was based up on increasing severity (i.e. the first time any targeted symptoms worsened after treatment relative to baseline).	From Day 1 (baseline) to Day 28
Percentage of Participants With a Resting Peripheral Oxygen Saturation >=95% at Days 1 and 5- mITT Population	In this outcome measure, the percentage of participants with a resting peripheral oxygen saturation >=95% were reported.	Day 1, 5
Percentage of Participants With a Resting Peripheral Oxygen Saturation >=95% at Days 1 and 5- mITT1 Population	In this outcome measure, the percentage of participants with a resting peripheral oxygen saturation >=95% were reported.	Day 1, 5
Percentage of Participants With a Resting Peripheral Oxygen Saturation >=95% at Days 1 and 5- mITT2 Population	In this outcome measure, the percentage of participants with a resting peripheral oxygen saturation >=95% were reported.	Day 1, 5
Percentage of Participants Who Died Through Week 24- mITT Population	In this outcome measure, percentage of participants with death due to any cause was presented.	From Day 1 up to Week 24
Percentage of Participants Who Died Through Week 24- mITT1 Population	In this outcome measure, percentage of participants with death due to any cause was presented.	From Day 1 up to Week 24
Percentage of Participants Who Died Through Week 24- mITT2 Population	In this outcome measure, percentage of participants with death due to any cause was presented.	From Day 1 up to Week 24
Plasma Concentration Versus Time Summary of PF-07321332		1 Hour post-dose on Day 1 and pre-dose on Day 5
Change From Baseline in Logarithm to Base10 (Log10) Transformed Viral Load at Day 3, 5, 10 and 14- mITT Population	The viral load was measured in nasal or nasopharyngeal samples using reverse transcription polymerase chain reaction (RT-PCR).	Baseline, Day 3, 5, 10 and 14
Change From Baseline in Log10 Transformed Viral Load at Day 3, 5, 10 and 14- mITT1 Population	The viral load was measured in nasal or nasopharyngeal samples using RT-PCR.	Baseline, Day 3, 5, 10 and 14
Change From Baseline in Log10 Transformed Viral Load at Day 3, 5, 10 and 14- mITT2 Population	The viral load was measured in nasal or nasopharyngeal samples using RT-PCR.	Baseline, Day 3, 5, 10 and 14
Number of COVID-19 Related Medical Visits- mITT Population	Medical visits included emergency room, practitioner's office, home healthcare services, urgent care, telephone consultation, outpatient infusion center, other, COVID-19-related-hospitalization (intensive care unit [ICU] and non-ICU stays). In this outcome measure, COVID-19-related medical visits of participants were reported.	From Day 1 up to Day 34
Number of COVID-19 Related Medical Visits- mITT1 Population	Medical visits included emergency room, practitioner's office, home healthcare services, urgent care, telephone consultation, outpatient infusion center, other, COVID-19-related-hospitalization (ICU and non-ICU stays). In this outcome measure, COVID-19-related medical visits of participants were reported.	From Day 1 up to Day 34
Number of COVID-19 Related Medical Visits- mITT2 Population	Medical visits included emergency room, practitioner's office, home healthcare services, urgent care, telephone consultation, outpatient infusion center, other, COVID-19-related-hospitalization (ICU and non-ICU stays). In this outcome measure, COVID-19-related medical visits of participants were reported.	From Day 1 up to Day 34
Number of Days in Hospital and ICU for the Treatment of COVID-19- mITT Population		From Day 1 up to Day 34
Number of Days in Hospital and ICU for the Treatment of COVID-19- mITT1 Population		From Day 1 up to Day 34
Number of Days in Hospital and ICU for the Treatment of COVID-19- mITT2 Population		From Day 1 up to Day 34

Collaborators and Investigators

• Sponsor: Pfizer
• Investigators: Study Director: Pfizer CT.gov Call Center, Pfizer

Publications and helpful links

General Publications

• Hammond J, Leister-Tebbe H, Gardner A, Abreu P, Bao W, Wisemandle W, Baniecki M, Hendrick VM, Damle B, Simon-Campos A, Pypstra R, Rusnak JM; EPIC-HR Investigators. Oral Nirmatrelvir for High-Risk, Nonhospitalized Adults with Covid-19. N Engl J Med. 2022 Apr 14;386(15):1397-1408. doi: 10.1056/NEJMoa2118542. Epub 2022 Feb 16.

Helpful Links

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

Study record dates

Study Major Dates

• Study Start (Actual): July 16, 2021
• Primary Completion (Actual): December 9, 2021
• Study Completion (Actual): April 25, 2022

Study Registration Dates

• First Submitted: July 10, 2021
• First Submitted That Met QC Criteria: July 10, 2021
• First Posted (Actual): July 13, 2021

Study Record Updates

• Last Update Posted (Actual): July 10, 2025
• Last Update Submitted That Met QC Criteria: July 8, 2025
• Last Verified: July 1, 2025

More Information

Terms related to this study

• Keywords: severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)
• Additional Relevant MeSH Terms: Respiratory Tract Infections; Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases; Lung Diseases; Pneumonia, Viral; Pneumonia; Coronavirus Infections; Coronaviridae Infections; Nidovirales Infections; COVID-19; Viral Protease Inhibitors; Anti-Infective Agents; Molecular Mechanisms of Pharmacological Action; Protease Inhibitors; Enzyme Inhibitors; Antiviral Agents; Cytochrome P-450 Enzyme Inhibitors; Anti-HIV Agents; Anti-Retroviral Agents; HIV Protease Inhibitors; Cytochrome P-450 CYP3A Inhibitors; Nirmatrelvir; Ritonavir
• Other Study ID Numbers: C4671005; 2021-002895-38 (EudraCT Number); EPIC-HR (Other Identifier: Alias Study Number)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD 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.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No