Clinical trial Recruiting at 148 sites Phase 3 Interventional Ages 18 and up

Ibuzatrelvir alone or with remdesivir for severely immunocompromised adults with COVID-19

Official title: 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

Run by Pfizer · NCT07013474 · Data updated 2026-11-12

This will test whether ibuzatrelvir, taken alone or together with remdesivir, helps severely immunocompromised adults who recently developed COVID-19 symptoms.

More COVID-19 Infection trials

Quick facts

PhasePhase 3
Study typeInterventional
Ages18 Years and up
SexAll
Enrollment300 (estimated)
SponsorPfizer
Industry-sponsored
Drugs / interventionsrituximab, CAR-T
Locations159 sites (Canoga Park, California and 158 other locations)
StatusRecruiting
StartedJuly 14, 2025
Main results expectedSeptember 28, 2027
Study endsFebruary 5, 2028
Registry record updatedOctober 14, 2026
Trial IDNCT07013474 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Adults (≥18) who are severely immunocompromised—for example due to organ transplant, active hematologic malignancy, recent CAR‑T/HCT, or B‑cell depleting therapy—with confirmed SARS‑CoV‑2 infection and symptom onset within the past five days, who are non‑hospitalized or hospitalized without need for supplemental oxygen.

Probably not a fit

People who require supplemental oxygen for COVID‑19, are not severely immunocompromised, are more than five days from symptom onset, or are under 18 are unlikely to qualify or receive benefit from this protocol.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This is a randomized, double-blinded, double-dummy, phase 3 trial that compares three arms: remdesivir IV alone, oral ibuzatrelvir alone, and the combination of ibuzatrelvir with remdesivir. Eligible adults are severely immunocompromised, have a confirmed SARS‑CoV‑2 infection, and developed symptoms within five days; participants may be non‑hospitalized or hospitalized only for observation or to receive the intervention and must not require supplemental oxygen. Ibuzatrelvir is taken orally twice daily while remdesivir is administered as a daily IV infusion, with matching placebos used to maintain blinding. The study tests both efficacy and safety outcomes to see if the oral drug, alone or with remdesivir, reduces progression or persistence of symptomatic COVID‑19 in this high‑risk group.

Why it matters

Potential benefit: If successful, the treatment options could shorten illness, prevent progression to severe COVID‑19, and reduce persistent infection in severely immunocompromised patients.

How similar studies have gone: Remdesivir has shown antiviral benefit in prior COVID‑19 studies, but ibuzatrelvir and the specific oral plus IV combination remain novel in this population and have not yet been proven effective.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. 18 years of age or older at screening who are non-hospitalized or hospitalized with mild to moderate COVID-19
2. 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.
3. 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.

Exclusion Criteria:

1. Severe or critical COVID-19, or current need for supplemental oxygen.
2. Receiving dialysis or have current kidney failure (ie, eGFR consistently \<15 mL/min)
3. Active liver disease
4. History of hypersensitivity or other contraindication to any of the components of the study interventions, as determined by the investigator
5. Suspected or confirmed concurrent active systemic infection other than COVID-19 that may interfere with the evaluation of response to the study intervention.
6. Life expectancy less than 30 days at study entry due to an underlying condition, in the judgement of the investigator.
7. 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.
8. Has received any other antiviral for the treatment of the current COVID-19 infection
9. Current use of any prohibited concomitant medication(s) or unwillingness or inability to use a required concomitant medication(s).
10. 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.
11. Prior participation in this trial or any clinical trial of ibuzatrelvir.
12. Females who are pregnant, breastfeeding, or who are planning to become pregnant within the timeframe of the study.
13. 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.

Where it's running

  • Hope Clinical Research, Inc.
    Canoga Park, California, United States
    Recruiting
  • Amicis Research Center - Granada Hills
    Granada Hills, California, United States
    Recruiting
  • Jacobs Medical Center at UC San Diego Health
    La Jolla, California, United States
    Recruiting
  • UC Davis CTSC Clinical Research Center
    Sacramento, California, United States
    Recruiting
  • University of California Davis Health
    Sacramento, California, United States
    Recruiting
  • UC San Diego Medical Center - Hillcrest
    San Diego, California, United States
    Recruiting
Show 44 more locations
  • University of California San Diego Health
    San Diego, California, United States
    Recruiting
  • UCHealth Anschutz Inpatient Pavilion - Anschutz Medical Campus
    Aurora, Colorado, United States
    Recruiting
  • University of Colorado Anschutz Medical Campus
    Aurora, Colorado, United States
    Recruiting
  • University of Colorado Clinical and Translational Research Center
    Aurora, Colorado, United States
    Recruiting
  • University of Colorado Hospital
    Aurora, Colorado, United States
    Recruiting
  • Georgetown University Medical Center
    Washington D.C., District of Columbia, United States
    Recruiting
  • BRP- Hialeah Hospital
    Hialeah, Florida, United States
    Recruiting
  • D&H Cancer Research Center LLC
    Margate, Florida, United States
    Recruiting
  • Kendall South Medical Center
    Miami, Florida, United States
    Recruiting
  • Velocity Clinical Research, Savannah
    Savannah, Georgia, United States
    Recruiting
  • Humphreys Diabetes Center
    Boise, Idaho, United States
    Recruiting
  • St. Luke's Idaho Elks Children's Pavilion
    Boise, Idaho, United States
    Recruiting
  • Northwestern Memorial Hospital
    Chicago, Illinois, United States
    Recruiting
  • Northwestern University Feinberg School of Medicine
    Chicago, Illinois, United States
    Recruiting
  • Johns Hopkins Hospital
    Baltimore, Maryland, United States
    Recruiting
  • Jadestone Clinical Research
    Silver Spring, Maryland, United States
    Recruiting
  • Brigham and Women's Hospital
    Boston, Massachusetts, United States
    Recruiting
  • Clinical Trials Center
    Boston, Massachusetts, United States
    Recruiting
  • Clinical Trials Hub
    Boston, Massachusetts, United States
    Recruiting
  • University of Massachusetts Chan Medical School
    Worcester, Massachusetts, United States
    Recruiting
  • University of Michigan
    Ann Arbor, Michigan, United States
    Recruiting
  • Henry Ford Hospital
    Detroit, Michigan, United States
    Recruiting
  • Holy Name Medical Center
    Teaneck, New Jersey, United States
    Recruiting
  • NYU Langone Health
    New York, New York, United States
    Recruiting
  • Duke Vaccine and Trials Unit
    Durham, North Carolina, United States
    Recruiting
  • Duke Vaccine and Trials Unit
    Durham, North Carolina, United States
    Recruiting
  • Duke University - Main Hospital and Clinics
    Durham, North Carolina, United States
    Recruiting
  • University of Cincinnati Medical Center
    Cincinnati, Ohio, United States
    Recruiting
  • University of Cincinnati College of Medicine (UC Holmes)
    Cincinnati, Ohio, United States
    Recruiting
  • Trc
    Pittsburgh, Pennsylvania, United States
    Recruiting
  • University of Pittsburgh Medical Center
    Pittsburgh, Pennsylvania, United States
    Recruiting
  • UPMC Division of Infectious Disease Clinic
    Pittsburgh, Pennsylvania, United States
    Recruiting
  • UPMC Presbyterian IDS
    Pittsburgh, Pennsylvania, United States
    Recruiting
  • UPMC Presbyterian Shadyside
    Pittsburgh, Pennsylvania, United States
    Recruiting
  • UPMC Hillman Cancer Center
    Pittsburgh, Pennsylvania, United States
    Recruiting
  • UPMC Shadyside IDS
    Pittsburgh, Pennsylvania, United States
    Recruiting
  • UPMC Shadyside
    Pittsburgh, Pennsylvania, United States
    Recruiting
  • Medical University of South Carolina Infectious Disease Clinic
    Charleston, South Carolina, United States
    Recruiting
  • Medical University of South Carolina Investigational Drug Services (IDS)
    Charleston, South Carolina, United States
    Recruiting
  • Medical University of South Carolina Investigational Drug Services Pharmacy
    Charleston, South Carolina, United States
    Recruiting
  • Medical University of South Carolina Research Nexus Clinic
    Charleston, South Carolina, United States
    Recruiting
  • Medical University of South Carolina Translational Research Nexus Clinic and Laboratory
    Charleston, South Carolina, United States
    Recruiting
  • Medical University of South Carolina
    Charleston, South Carolina, United States
    Recruiting
  • West Tennessee Research Institute
    Jackson, Tennessee, United States
    Recruiting

+109 more sites. See ClinicalTrials.gov for the full list.

Study contacts

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How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.