臨床研究等提出・公開システム

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

A Study to Learn About the Study Medicine Ibuzatrelvir in Adults With COVID-19 Who Are Severely Immunocompromised

Kawai Norisuke

Pfizer R&D Japan G.K.

Shinjuku Bunka Quint Bldg., 3-22-7 Yoyogi, Shibuya-ku, Tokyo

clinical-trials@pfizer.com

Clinical Trials Information Desk

Pfizer R&D Japan G.K.

Shinjuku Bunka Quint Bldg., 3-22-7 Yoyogi, Shibuya-ku, Tokyo

+81-3-5309-7000

clinical-trials@pfizer.com

Recruiting

July. 14, 2025

Interventional

randomized controlled trial

double blind

active control

parallel assignment

treatment purpose

1. 18 years of age or older at screening who are non-hospitalized or hospitalized for observation or with the intent of administering the study intervention.
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.

1. Severe COVID-19, or current need for supplemental oxygen for treatment of COVID-19.
2. Receiving dialysis or have current kidney failure (ie, eGFR consistently <15 mL/min/1.73 m2)
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.

Both

COVID-19

Drug: ibuzatrelvir
tablet
Drug: remdesivir
injection, for intravenous use
Other Names:
veklury
Drug: placebo for ibuzatrelvir
tablet
Drug: placebo for remdesivir
injection, for intravenous use

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 [Time Frame: 38 days]
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

Time to sustained alleviation of all targeted COVID-19 symptoms [Time Frame: 38 days]
The difference in median time to sustained alleviation of all targeted symptoms. Symptoms will be assessed through a daily electronic diary and include sore throat, cough, fever and diarrhea, among others.

Proportion of participants with evidence of recurrent or persistent SARS-CoV-2 infection. [Time Frame: 38 days]
The viral load is measured in nasal or nasopharyngeal samples using reverse transcription polymerase chain reaction (RT-PCR)

Proportion of participants with COVID-19-related ED visits with administration of supplemental oxygen, COVID-19 antiviral, or IV treatment (eg, hydration, antibiotics, or corticosteroids), COVID-19-related hospitalization, or all-cause mortality. [Time Frame: 38 days]

Change from baseline in SARS-CoV-2 RNA level in NP or nasal swabs over time [Time Frame: 38 days]
The viral load is measured in nasal or nasopharyngeal samples using reverse transcription polymerase chain reaction (RT-PCR)

Proportion of participants with SARS-CoV-2 NP or nasal RNA <LLOQ at each time point [Time Frame: 38 days]

Proportion of participants with viral rebound in SARS-CoV-2 RNA level in NP or nasal swabs [Time Frame: 38 days]
Virologic rebound is defined as:
Viral RNA is not detectable at the end of treatment, and later is detectable through Day 38
Viral RNA is detected at end of treatment, and viral RNA levels increase further through Day 38

Time to sustained NP or nasal swab SARS-CoV-2 RNA <LLOQ [Time Frame: 38 days]

Incidence of Treatment emergent adverse events, serious adverse events, and adverse events leading to discontinuation [Time Frame: 38 days]

+81-948-22-3800

May. 07, 2025

Yes

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.

South Korea/Spain/Taiwan/United States