A Study of How Ibuzatrelvir is Taken up Into the Blood of Healthy Adults After Taking Different Tablets of Ibuzatrelvir

NCT07552779 | Recruiting Phase 1 FDA Drug

• 2 other identifiers: C50910292025-525041-43-00
• Study Type: interventional
• Target: 18
• Locations: 1 country
• Sites: 1

Brief Summary

Healthy adults will be enrolled into this open-label, Phase 1 research study. Participants will spend about 9 nights and 10 days in the clinical research unit (CRU) and the total time in the study will be about 11 weeks. The goal of this clinical trial is to compare how much of the study drug ibuzatrelvir is in participants' blood after taking one of the two different types of tablets containing the same amount of ibuzatrelvir without food. The study will also measure how much ibuzatrelvir is in participants' blood after taking one type of the tablets dispersed in water and when one type of the tablets is taken with food. This study drug is taken by mouth.

Conditions

Coronavirus Disease 2019; COVID-19; Pneumonia; Coronavirus Disease 2019 (COVID-19); Upper Respiratory Tract Infections; Respiratory Tract Infection; Respiratory Tract Diseases; COVID-19 Infection; COVID-19 SARS-CoV-2 Infection; Lung Diseases; COVID-19 (Coronavirus Disease 2019)

Keywords

COVID-19 infection; Pneumonia; Respiratory tract infections; Coronavirus infection; RNA virus infection; Lung disease; Pneumonia, viral; Infections; Viral protease inhibitor; Protease inhibitor; Enzyme inhibitor; Anti-viral agents; Anti-infectives; Ibuzatrelvir; COVID-19

Outcome Measures

Primary Outcomes (4)

• Plasma ibuzatrelvir AUCinf (as data permit, otherwise AUClast) in the fasted state

  Relative bioavailability of a new oral formulation of ibuzatrelvir compared to the original tablet formulation in the fasted state

  Hour 0 pre-dose in each period and 0.5, 1, 2, 4, 6, 8, 12, 24, and 48 post-dose in each period

• Plasma ibuzatrelvir AUCinf (as data permit, otherwise AUClast) in the fasted state

  Relative bioavailability of a dispersion of a new oral formulation of ibuzatrelvir compared to the original tablet formulation in the fasted state

  Hour 0 pre-dose in each period and 0.5, 1, 2, 4, 6, 8, 12, 24, and 48 post-dose in each period

• Plasma ibuzatrelvir Cmax in the fasted state

  Relative bioavailability of a new oral formulation of ibuzatrelvir compared to the original tablet formulation in the fasted state

  Hour 0 pre-dose in each period and 0.5, 1, 2, 4, 6, 8, 12, 24, and 48 post-dose in each period

• Plasma ibuzatrelvir Cmax in the fasted state

  Relative bioavailability of a dispersion of a new oral formulation of ibuzatrelvir compared to the original tablet formulation in the fasted state

  Hour 0 pre-dose in each period and 0.5, 1, 2, 4, 6, 8, 12, 24, and 48 post-dose in each period

Secondary Outcomes (3)

• Incidence of AEs, clinical laboratory measurements, vital signs, and standard 12-lead ECGs

  Day 1-35

• Plasma ibuzatrelvir AUCinf (as data permit, otherwise AUClast)

  Hour 0 pre-dose in each period and 0.5, 1, 2, 4, 6, 8, 12, 24, and 48 post-dose in each period

• Plasma ibuzatrelvir Cmax

  Hour 0 pre-dose in each period and 0.5, 1, 2, 4, 6, 8, 12, 24, and 48 post-dose in each period

Study Arms (4)

Treatment A

EXPERIMENTAL

single dose of ibuzatrelvir original tablet formulation in the fasted state on Day 1 of the treatment period

Drug: Ibuzatrelvir co-process API film coated tablet

Treatment B

EXPERIMENTAL

single dose of ibuzatrelvir new tablet formulation in the fasted state on Day 1 of the treatment period

Drug: Ibuzatrelvir filmcoated tablet

Treatment C

EXPERIMENTAL

single dose of ibuzatrelvir of the new tablet formulation dispersed in water and given in the fasted state on Day 1 of the treatment period

Drug: Ibuzatrelvir filmcoated tablet

Treatment D

EXPERIMENTAL

single dose of ibuzatrelvir new tablet formulation in the fed state on Day 1 of the treatment period

Drug: Ibuzatrelvir filmcoated tablet

Interventions

Ibuzatrelvir co-process API film coated tablet DRUG

original

Treatment A

Ibuzatrelvir filmcoated tablet DRUG

new

Treatment B; Treatment C; Treatment D

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• years of age or older (or the minimum age of consent in accordance with local regulations) at screening who are overtly healthy as determined by medical evaluation including medical history, physical examination, laboratory tests, and ECGs.
• BMI of 16-32 kg/m2; and a total body weight \>45 kg.
• Participants who are capable of giving signed informed consent and willing and able to comply with all scheduled visits, treatment plans, laboratory tests, lifestyle considerations, and other study procedures.

You may not qualify if:

• Evidence or history of clinically significant hematological, renal, endocrine, pulmonary, gastrointestinal, cardiovascular, hepatic, psychiatric, neurological, or allergic disease (including drug allergies, but excluding untreated, asymptomatic, seasonal allergies at the time of dosing).
• Any condition possibly affecting drug absorption (eg, gastrectomy, cholecystectomy).
• History of HIV infection, hepatitis B, or hepatitis C; positive testing for HIV, HBsAg, or HCVAb. Hepatitis B vaccination is allowed.
• Any medical or psychiatric condition including any active suicidal ideation in the past year or suicidal behavior in the past 5 years or laboratory abnormality or other conditions that may increase the risk of study participation or, in the investigator's judgment, make the participant inappropriate for the study.
• Use of prescription or nonprescription drugs and dietary and herbal supplements within 14 days or 5 half-lives (whichever is longer) prior to the first dose of study intervention with the exception of moderate or strong CYP3A inducers which are prohibited within 14 days plus 5 half-lives prior to the first dose of study intervention.
• Previous administration of an investigational product (drug or vaccine) within 30 days or 5 half-lives preceding the first dose of study intervention used in this study (whichever is longer).
• Participation in studies of other investigational products (drug or vaccine) at any time during participation in this study.
• A positive urine drug test. A single repeat for positive drug screen may be allowed.
• Screening supine BP ≥140 mm Hg (systolic) or ≥90 mm Hg (diastolic) for participants \<60 years; and ≥150/90 mm/Hg for participants ≥60 years old, following at least 5 minutes of supine rest. If systolic BP is ≥140 or 150 mm Hg (based on age) or diastolic ≥90 mm Hg, the BP should be repeated 2 more times and the average of the 3 BP values should be used to determine the participant's eligibility.
• An eGFR \<60 mL/min/1.73 m² as determined by the CKD-EPI equation using Screat.
• Standard 12 lead ECG that demonstrates clinically relevant abnormalities that may affect participant safety or interpretation of study results (including, but not limited to, QTcF \>450 ms, complete LBBB, signs of an acute or indeterminate age myocardial infarction, ST segment and/or T wave changes suggestive of myocardial ischemia, second or third degree AV block, or serious bradyarrhythmias or tachyarrhythmias). If QTcF exceeds 450 ms, or QRS exceeds 120 ms, the ECG should be repeated twice and the average of the 3 QTcF or QRS values used to determine the participant's eligibility. Computer interpreted ECGs with abnormal findings should be overread by an investigator experienced in reading ECGs before excluding a participant.
• Participants with ANY of the following abnormalities in clinical laboratory tests at screening, as assessed by the study specific laboratory and confirmed by a single repeat test, if deemed necessary:
• ALT, AST, T Bili \>1.5× ULN.
• History of alcohol abuse or repeated binge drinking and/or any other illicit drug use or dependence within 6 months of screening. Binge drinking is defined as a pattern of 5 (male) and 4 (female) or more alcoholic drinks in about 2 hours. As a general rule, alcohol intake should not exceed 14 units per week (1 unit = 8 ounces (240 mL) beer, 1 ounce (30 mL) of 40% spirit, or 3 ounces (90 mL) of wine).
• 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.

Sponsors & Collaborators

• Pfizer: lead

Study Sites (1)

Pfizer Clinical Research Unit - Brussels

Brussels, Bruxelles-capitale, Région de, B-1070, Belgium

RECRUITING

Related Links

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

MeSH Terms

Conditions

COVID-19; Respiratory Tract Infections; Respiratory Tract Diseases; Pneumonia; Lung Diseases; Coronavirus Infections; RNA Virus Infections; Pneumonia, Viral; Infections

Condition Hierarchy (Ancestors)

Virus Diseases; Coronaviridae Infections; Nidovirales Infections

Study Officials

• Pfizer CT.gov Call Center

  Pfizer

  STUDY DIRECTOR

Central Study Contacts

Pfizer CT.gov Call Center

CONTACT

1-800-718-1021; ClinicalTrials.gov_Inquiries@pfizer.com

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Randomized, single-dose, 4-period, 6-sequence crossover study

Study Record Dates

• First Submitted: April 7, 2026
• First Posted: April 27, 2026
• Study Start: April 13, 2026
• Primary Completion (Estimated): June 3, 2026
• Study Completion (Estimated): July 6, 2026
• Last Updated: April 27, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

BE (1)