A Study to Learn About the Study Medicine Ibuzatrelvir in Adults With COVID-19 Who Are Severely Immunocompromised
AN INTERVENTIONAL EFFICACY AND SAFETY, PHASE 3, RANDOMIZED, DOUBLE-BLIND, 3-ARM STUDY TO INVESTIGATE IBUZATRELVIR IN ADULTS WITH SYMPTOMATIC COVID-19 WHO ARE SEVERELY IMMUNOCOMPROMISED
2 other identifiers
interventional
300
18 countries
152
Brief Summary
This is a Phase 3, randomized, actively controlled, double-blinded, double-dummy, superiority study to evaluate the efficacy and safety of ibuzatrelvir alone and in combination with remdesivir IV compared to remdesivir IV alone for the treatment of symptomatic COVID-19 in severely immunocompromised adult participants who are non-hospitalized or are hospitalized for observation or study intervention administration but do not require supplemental oxygen for COVID-19.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P50-P75 for phase_3
Started Jul 2025
Typical duration for phase_3
152 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
May 5, 2025
CompletedFirst Posted
Study publicly available on registry
June 10, 2025
CompletedStudy Start
First participant enrolled
July 14, 2025
CompletedPrimary Completion
Last participant's last visit for primary outcome
September 27, 2027
ExpectedStudy Completion
Last participant's last visit for all outcomes
February 25, 2028
July 30, 2026
July 1, 2026
2.2 years
May 5, 2025
July 29, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (1)
The difference in the proportion of patients meeting the primary composite endpoint, between ibuzatrelvir and remdesivir vs remdesivir groups in symptomatic adult participants with COVID-19 who are severely immunocompromised
The difference in the proportion of participants with the composite endpoint of a) COVID-19-related ED visits with administration of supplemental oxygen, COVID-19 antiviral, or IV treatment; COVID-19-related hospitalization; or all-cause mortality, and b) Evidence of recurrent or persistent SARS-CoV-2 infection
38 days
Secondary Outcomes (8)
Time to sustained alleviation of all targeted COVID-19 symptoms
38 days
Proportion of participants with evidence of recurrent or persistent SARS-CoV-2 infection.
38 days
Proportion of participants with COVID-19-related ED visits with administration of supplemental oxygen, COVID-19 antiviral, or IV treatment, COVID-19-related hospitalization, or all-cause mortality.
38 days
Change from baseline in SARS-CoV-2 RNA level in NP or nasal swabs over time
38 days
Proportion of participants with SARS-CoV-2 NP or nasal RNA <LLOQ at each time point
38 days
- +3 more secondary outcomes
Study Arms (3)
Ibuzatrelvir
EXPERIMENTALParticipants will receive ibuzatrelvir orally twice a day + IV placebo for remdesivir
Ibuzatrelvir + Remdesivir
EXPERIMENTALParticipants will receive ibuzatrelvir orally twice a day + IV remdesivir
Remdesivir
EXPERIMENTALParticipants will receive placebo for ibuzatrelvir orally twice a day + IV remdesivir
Interventions
injection, for intravenous use
Eligibility Criteria
You may qualify if:
- years of age or older at screening who are non-hospitalized or hospitalized for observation or with the intent of administering the study intervention.
- Confirmed SARS-CoV-2 infection as determined by RAT (or other locally approved test) collected within 2 days prior to randomization. Initial onset of symptoms attributable to COVID-19 within 5 days prior to the day of randomization and at least 1 of the specified symptoms attributable to COVID-19 present on the day of randomization.
- Severely immunocompromised due to:
- Solid organ or islet cell transplant recipient who is receiving immunosuppressive therapy;
- Active hematologic malignancy (eg, chronic lymphocytic leukemia, non-Hodgkin lymphoma, multiple myeloma, acute leukemia);
- Receipt of CAR-T-cell therapy or HCT either within 2 years of transplantation or who are receiving immunosuppressive therapy;
- Currently receiving or recently received B-cell depleting therapies (eg, rituximab), where the immunosuppressive effect is still ongoing.
You may not qualify if:
- Severe COVID-19, or current need for supplemental oxygen for treatment of COVID-19.
- Receiving dialysis or have current kidney failure (ie, eGFR consistently \<15 mL/min/1.73 m2)
- Active liver disease
- History of hypersensitivity or other contraindication to any of the components of the study interventions, as determined by the investigator
- Suspected or confirmed concurrent active systemic infection other than COVID-19 that may interfere with the evaluation of response to the study intervention.
- Life expectancy less than 30 days at study entry due to an underlying condition, in the judgement of the investigator.
- Any medical or psychiatric condition including recent (within the past year) or active suicidal ideation/behavior or laboratory abnormality that may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study.
- Has received any other antiviral for the treatment of the current COVID-19 infection
- Current use of any prohibited concomitant medication(s) or unwillingness or inability to use a required concomitant medication(s).
- Current or previous administration of an investigational product (drug or vaccine) within 30 days (or as determined by local requirement) or 5 half lives preceding the first dose of study intervention used in this study (whichever is longer). Authorized or products with conditional approval are not considered investigational.
- Prior participation in this trial or any clinical trial of ibuzatrelvir.
- Females who are pregnant, breastfeeding, or who are planning to become pregnant within the timeframe of the study.
- Investigator site staff directly involved in the conduct of the study and their family members, site staff otherwise supervised by the investigator, and sponsor and sponsor delegate employees directly involved in the conduct of the study and their family members.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Pfizerlead
Study Sites (152)
Hope Clinical Research, Inc.
Canoga Park, California, 91303, United States
Amicis Research Center - Granada Hills
Granada Hills, California, 91344, United States
Jacobs Medical Center at UC San Diego Health
La Jolla, California, 92037, United States
UC Davis CTSC Clinical Research Center
Sacramento, California, 95817, United States
University of California Davis Health
Sacramento, California, 95817, United States
UC San Diego Medical Center - Hillcrest
San Diego, California, 92103, United States
University of California San Diego Health
San Diego, California, 92103, United States
UCHealth Anschutz Inpatient Pavilion - Anschutz Medical Campus
Aurora, Colorado, 80045, United States
University of Colorado Anschutz Medical Campus
Aurora, Colorado, 80045, United States
University of Colorado Clinical and Translational Research Center
Aurora, Colorado, 80045, United States
University of Colorado Hospital
Aurora, Colorado, 80045, United States
Georgetown University Medical Center
Washington D.C., District of Columbia, 20007, United States
BRP- Hialeah Hospital
Hialeah, Florida, 33013, United States
D&H Cancer Research Center LLC
Margate, Florida, 33063, United States
Kendall South Medical Center
Miami, Florida, 33185, United States
Velocity Clinical Research, Savannah
Savannah, Georgia, 31406, United States
Humphreys Diabetes Center
Boise, Idaho, 83702, United States
St. Luke's Idaho Elks Children's Pavilion
Boise, Idaho, 83712, United States
Northwestern Memorial Hospital
Chicago, Illinois, 60611, United States
Northwestern University Feinberg School of Medicine
Chicago, Illinois, 60611, United States
Johns Hopkins Hospital
Baltimore, Maryland, 21287, United States
Jadestone Clinical Research
Silver Spring, Maryland, 20904, United States
Brigham and Women's Hospital
Boston, Massachusetts, 02115, United States
Clinical Trials Center
Boston, Massachusetts, 02115, United States
Clinical Trials Hub
Boston, Massachusetts, 02115, United States
University of Massachusetts Chan Medical School
Worcester, Massachusetts, 01655, United States
University of Michigan
Ann Arbor, Michigan, 48109, United States
Henry Ford Hospital
Detroit, Michigan, 48202, United States
Profound Research LLC
Farmington Hills, Michigan, 48334, United States
Holy Name Medical Center
Teaneck, New Jersey, 07666, United States
Duke Vaccine and Trials Unit
Durham, North Carolina, 27703, United States
Duke Vaccine and Trials Unit
Durham, North Carolina, 27705, United States
Duke University - Main Hospital and Clinics
Durham, North Carolina, 27710, United States
University of Cincinnati Medical Center
Cincinnati, Ohio, 45219, United States
University of Cincinnati College of Medicine (UC Holmes)
Cincinnati, Ohio, 45267, United States
TRC
Pittsburgh, Pennsylvania, 15213, United States
University of Pittsburgh Medical Center
Pittsburgh, Pennsylvania, 15213, United States
UPMC Division of Infectious Disease Clinic
Pittsburgh, Pennsylvania, 15213, United States
UPMC Presbyterian IDS
Pittsburgh, Pennsylvania, 15213, United States
UPMC Presbyterian Shadyside
Pittsburgh, Pennsylvania, 15213, United States
UPMC Hillman Cancer Center
Pittsburgh, Pennsylvania, 15232, United States
UPMC Shadyside IDS
Pittsburgh, Pennsylvania, 15232, United States
UPMC Shadyside
Pittsburgh, Pennsylvania, 15232, United States
Medical University of South Carolina Infectious Disease Clinic
Charleston, South Carolina, 29425, United States
Medical University of South Carolina Investigational Drug Services (IDS)
Charleston, South Carolina, 29425, United States
Medical University of South Carolina Investigational Drug Services Pharmacy
Charleston, South Carolina, 29425, United States
Medical University of South Carolina Research Nexus Clinic
Charleston, South Carolina, 29425, United States
Medical University of South Carolina Translational Research Nexus Clinic and Laboratory
Charleston, South Carolina, 29425, United States
Medical University of South Carolina
Charleston, South Carolina, 29425, United States
West Tennessee Research Institute
Jackson, Tennessee, 38305, United States
Zenos Clinical Research
Dallas, Texas, 75230, United States
Baylor Scott & White Health - Center for Advanced Heart and Lung Disease
Dallas, Texas, 75246, United States
Baylor Scott & White Research Institute - Clinical Trials Office
Dallas, Texas, 75246, United States
Baylor University Medical Center
Dallas, Texas, 75246, United States
Houston Methodist Hospital
Houston, Texas, 77030, United States
Memorial Hermann Hospital
Houston, Texas, 77030, United States
The University of Texas Health Science Center at Houston
Houston, Texas, 77030, United States
UT Physicians
Houston, Texas, 77030, United States
Seattle Rheumatology Associates
Seattle, Washington, 98104, United States
Swedish Ambulatory Infusion Center- First Hill
Seattle, Washington, 98104, United States
Swedish Cancer Institute Treatment Center
Seattle, Washington, 98104, United States
Swedish Medical Center- Innovative Therapeutics & Research Unit
Seattle, Washington, 98104, United States
Swedish Organ Transplant and Liver Center
Seattle, Washington, 98104, United States
Fred Hutchinson Cancer Center
Seattle, Washington, 98109, United States
Fred Hutchinson South Lake Union Clinic
Seattle, Washington, 98109, United States
Swedish Medical Center - First Hill Campus
Seattle, Washington, 98122, United States
University of Washington Medical Center
Seattle, Washington, 98195, United States
Hospital Italiano de La Plata
La Plata, Buenos Aires, B1900XI, Argentina
Hospital Italiano de Buenos Aires
ABB, Buenos Aires F.D., C1199ABB, Argentina
Instituto Médico Río Cuarto
Río Cuarto, Córdoba Province, X5800AEV, Argentina
Sanatorio Sagrado Corazón
Buenos Aires, 1039, Argentina
UZ Brussel
Brussels, Brussels Capital, 1090, Belgium
Université Libre de Bruxelles - Hôpital Erasme
Brussels, Bruxelles-capitale, Région de, 1070, Belgium
AZ Sint-Jan Brugge-Oostende AV
Bruges, West-vlaanderen, 8000, Belgium
Jules Bordet Institute
Anderlecht, 1070, Belgium
School of Medicine Federal University of Minas Gerais
Belo Horizonte, Minas Gerais, 30130-100, Brazil
Hospital Nossa Senhora das Graças
Curitiba, Paraná, 80810-040, Brazil
Centro Médico São Francisco
Curitiba, Paraná, 80810-050, Brazil
Hospital de Clinicas de Porto Alegre
Bairro Santa Cecília, Rio Grande do Sul, 90630-165, Brazil
Hospital e Maternidade Celso Pierro
Campinas, São Paulo, 13060-803, Brazil
CECIP - Centro de Estudos do Interior Paulista
Jaú, São Paulo, 17201130, Brazil
Instituto Nacional de Infectologia Evandro Chagas
Rio de Janeiro, 21040-360, Brazil
Icesp - Instituto Do Câncer Do Estado de São Paulo
São Paulo, 01246-000, Brazil
Sociedade Beneficente Israelita Brasileira Hospital Albert Einstein
São Paulo, 05652-900, Brazil
Rigshospitalet
Copenhagen, Capital Region, 2100, Denmark
Aarhus Universitetshospital, Skejby
Aarhus, Central Jutland, 8200, Denmark
Odense Universitetshospital
Odense, Region Syddanmark, 5000, Denmark
Aalborg Universitetshospital, Syd
Gistrup, 9260, Denmark
Hopital Claude Huriez - CHU de Lille
Lille, NORD, 59037, France
Centre Hospitalier Universitaire Dijon Bourgogne - Hôpital François Mitterrand
Dijon, 21000, France
Hôpital Saint Antoine
Paris, 75012, France
Hôpital Bichat - Claude-Bernard
Paris, 75018, France
Hôpital Saint-Louis
Paris, Île-de-France Region, 75010, France
TUM Klinikum
München, Bavaria, 81675, Germany
Universitaetsklinikum Koeln
Cologne, North Rhine-Westphalia, 50937, Germany
UKE Hamburg
Hamburg, 20246, Germany
University General Hospital of Alexandroupoli
Alexandroupoli, Anatolikí Makedonía KAI Thráki, 681 00, Greece
Evangelismos General Hospital of Athens
Athens, Attikí, 106 76, Greece
Alexandra General Hospital of Athens
Athens, Attikí, 115 28, Greece
General Hospital of Athens "Laiko"
Athens, Attikí, 11527, Greece
University General Hospital of Heraklion
Irakleio, 715 00, Greece
Ippokrateio General Hospital of Thessaloniki
Thessaloniki, 546 42, Greece
Fujita Health University Hospital
Toyoake, Aichi-ken, 470-1192, Japan
International University of Health and Welfare Narita Hospital
Narita, Chiba, 286-8520, Japan
Aso Iizuka Hospital
Iizuka, Fukuoka, 820-8505, Japan
Rinku General Medical Center
Izumisano, Osaka, 598-8577, Japan
Tokyo Medical University Hachioji Medical Center
Hachiōji, Tokyo, 1930998, Japan
National Center for Global Health and Medicine
Shinjuku, Tokyo, 162-8655, Japan
Tachikawa Hospital
Tachikawa, Tokyo, 190-8531, Japan
National Hospital Organization Kyushu Medical Center
Fukuoka, 810-8563, Japan
Nagasaki University Hospital
Nagasaki, 852-8501, Japan
Saga University Hospital
Saga, 849-8501, Japan
Fundación Santos y de la Garza Evia I.B.P
San Pedro Garza García, Nuevo León, 66278, Mexico
FAICIC S. de R.L. de C.V.
Veracruz, Veracruz Ignacio de LA Llave, 91900, Mexico
Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran
Mexico City, 14080, Mexico
Radboudumc
Nijmegen, 6525 GA, Netherlands
Erasmus MC
Rotterdam, 3015GD, Netherlands
BRCR Global Puerto Rico
San Juan, United States of America, 00907-1509, Puerto Rico
BRCR Medical Center - Ponce
Ponce, 00717, Puerto Rico
Canas Medical Center
Ponce, 00728, Puerto Rico
Fakultna nemocnica s poliklinikou F.D.Roosevelta Banska Bystrica
Banská Bystrica, Banská Bystrica Region, 974 01, Slovakia
Narodny ustav detskych chorob
Bratislava, Bratislava Region, 833 40, Slovakia
Fakultna nemocnica Trnava
Trnava, Trnava Region, 917 02, Slovakia
Narodny onkologicky ustav
Bratislava, 833 10, Slovakia
Nemocnica s poliklinikou Stefana Kukuru Michalovce, a.s.
Michalovce, 07101, Slovakia
Gachon University Gil Medical Center
Namdong-gu, Incheon-gwangyeoksi [incheon], 21565, South Korea
Chonnam National University Hospital
Gwangju, Kwangju-kwangyǒkshi, 61469, South Korea
The Catholic University of Korea, Eunpyeong St. Mary's Hospital
Seoul, Seoul-teukbyeolsi [seoul], 03312, South Korea
Asan Medical Center
Seoul, Seoul-teukbyeolsi [seoul], 05505, South Korea
CHUAC-Complejo Hospitalario Universitario A Coruña
A Coruña, A Coruña [LA Coruña], 15006, Spain
Hospital Universitario Reina Sofia
Córdoba, Andalusia, 14004, Spain
Hospital Germans Trias i Pujol
Badalona, Barcelona [barcelona], 08916, Spain
Parc de Salut Mar - Hospital del Mar
Barcelona, Barcelona [barcelona], 08003, Spain
Hospital Universitari Vall d'Hebron
Barcelona, Barcelona [barcelona], 08035, Spain
Hospital de la Santa Creu i Sant Pau
Barcelona, Catalunya [cataluña], 08041, Spain
Hospital Universitario La Paz
Madrid, Madrid, Comunidad de, 28046, Spain
CHUVI- Hospital Alvaro Cunqueiro
Vigo, Pontevedra [pontevedra], 36212, Spain
Hospital General Universitario Dr. Balmis
Alicante, 03010, Spain
Hospital Universitario Virgen de Valme
Seville, 41014, Spain
Skånes Universitetssjukhus Malmö
Malmö, Skåne LÄN [se-12], 205 02, Sweden
Karolinska Universitetssjukhuset Huddinge
Huddinge, 141 86, Sweden
Far Eastern Memorial Hospital
New Taipei City, NEW Taipei, 220, Taiwan
Kaohsiung Medical University Chung-Ho Memorial Hospital
Kaohsiung City, 807, Taiwan
Taichung Veterans General Hospital
Taichung, 407, Taiwan
Taipei Veterans General Hospital
Taipei, 11217, Taiwan
Acibadem Universitesi Atakent Hastanesi
Istanbul, İ̇stanbul, 34303, Turkey (Türkiye)
Hacettepe Universite Hastaneleri
Ankara, 06230, Turkey (Türkiye)
Ibni Sina Hospital
Ankara, 06230, Turkey (Türkiye)
Gaziantep Universitesi Sahinbey Arastirma ve Uygulama Hastanesi
Gaziantep, 27310, Turkey (Türkiye)
Kocaeli Üniversitesi
Kocaeli, 41380, Turkey (Türkiye)
Sakarya Training and Research Hospital
Sakarya, 54100, Turkey (Türkiye)
Karadeniz Technical University
Trabzon, 61080, Turkey (Türkiye)
Related Links
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Study Officials
- STUDY DIRECTOR
Pfizer CT.gov Call Center
Pfizer
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 3
- Allocation
- RANDOMIZED
- Masking
- TRIPLE
- Who Masked
- PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
- Masking Details
- This is a double-blind study, with required dedicated unblinded staff for dose preparation for remdesivir and placebo for remdesivir.
- Purpose
- TREATMENT
- Intervention Model
- PARALLEL
- Sponsor Type
- INDUSTRY
- Responsible Party
- SPONSOR
Study Record Dates
First Submitted
May 5, 2025
First Posted
June 10, 2025
Study Start
July 14, 2025
Primary Completion (Estimated)
September 27, 2027
Study Completion (Estimated)
February 25, 2028
Last Updated
July 30, 2026
Record last verified: 2026-07
Data Sharing
- IPD Sharing
- Will share
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.