A Study to Learn How a Medicine That Reduces Stomach Acid Affects the Level of Sisunatovir in the Blood of Healthy Adults.

NCT06105983 | Completed Phase 1 FDA Drug

• 2 other identifiers: C52410172023-507116-12-00
• Study Type: interventional
• Target: 40
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to see how rabeprazole affects the level of the study medicine sisunatovir in the blood of healthy adult participants. Rabeprazole is a medicine that reduces the amount of acid the stomach makes. The information from this study may inform how sisunatovir will be used in the future with medicines that reduce stomach acid. This study is seeking healthy participants who:

• are aged 18 years of age or older.
• are confirmed to be healthy by some medical tests. This study can include both men and women. Women who can produce a baby must agree to use a highly effective method of birth control.
• have body mass index (BMI) of 16 to 32 kilograms per meter squared.
• a total body weight of more than 45 kilograms. Participants will receive sisunatovir tablets by mouth on Day 1. After at least 48 hours, participants will take rabeprazole tablets by mouth once a day for 7 days. On the last (7th) day of rabeprazole dosing, another dose of sisunatovir tablets will be taken by mouth. The study will look at the blood levels of sisunatovir with and without taking rabeprazole. This will help see how sisunatovir should be given in the future. The total planned time of participation is about 10 to 11 weeks. The study consists of:
• screening period of up to 28 days before taking sisunatovir.
• 13 days of staying in the study clinic.
• a follow-up contact that will occur 28 to 35 days after taking sisunatovir the last time.

Conditions

Healthy

Outcome Measures

Primary Outcomes (3)

• Maximum Observed Plasma Concentration (Cmax)

  0 to 72 hour postdose

• Area Under the Curve From Time Zero to Extrapolated Infinite Time (AUCinf)

  AUCinf = Area under the plasma concentration versus time curve (AUC) from time zero (pre-dose) to extrapolated infinite time (0-inf). It is obtained from AUC (0-t) plus AUC (t-inf).

  0 to 72 hours postdose

• Area Under the Curve From Time Zero to Last Quantifiable Concentration (AUClast)

  Area under the plasma concentration time-curve from zero to the last measured concentration (AUClast)

  0 to 72 hours postdose

Secondary Outcomes (3)

• Number of Participants With Treatment Emergent Treatment-Related Adverse Events (AEs)

  Baseline up to 35 days after last dose of study intervention

• Number of Participants With Clinical Laboratory Abnormalities

  Baseline to Study Day 12 (Part 1) or Study Day 20 (Part 2)

• Number of Participants With Clinically Significant Change From Baseline in Vital Signs

  Baseline to Study Day 12 (Part 1) or Study Day 20 (Part 2)

Study Arms (5)

Treatment A

EXPERIMENTAL

Part 1: Sisunatovir without rabeprazole

Drug: Sisunatovir

Treatment B

ACTIVE COMPARATOR

Part 1: Sisunatovir with 40 mg rabeprazole

Drug: Sisunatovir; Drug: Rabeprazole 40 mg

Treatment C

ACTIVE COMPARATOR

Part 2: Sisunatovir suspension without rabeprazole

Drug: Sisunatovir suspension

Treatment D

EXPERIMENTAL

Part 2: Sisunatovir suspension with 20 mg rabeprazole

Drug: Sisunatovir suspension; Drug: Rabeprazole 20 mg

Treatment E

EXPERIMENTAL

Part 2: Sisunatovir suspension with 40 mg rabeprazole

Drug: Rabeprazole 40 mg; Drug: Sisunatovir suspension

Interventions

Sisunatovir DRUG

Single Dose

Treatment A; Treatment B

Rabeprazole 40 mg DRUG

Tablets once daily for 7 days

Treatment B; Treatment E

Sisunatovir suspension DRUG

Tablets once daily for 7 days

Treatment C; Treatment D; Treatment E

Rabeprazole 20 mg DRUG

Tablets once daily for 7 days

Treatment D

Eligibility Criteria

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

You may qualify if:

• Male and female participants aged 18 years 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, blood pressure, pulse rate and standard 12-lead electrocardiogram (ECG).
• Body mass index (BMI) of 16-32 kg/m2; and a total body weight \>45 kg

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 medical or psychiatric condition including recent (within the past year) or active suicidal ideation/behavior 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.
• Previous administration with an investigational product (drug or vaccine) within 30 days (or as determined by the local requirement) 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 their participation in this study.
• A positive urine drug test at screening or admission.
• A positive serum pregnancy test at screening and/or positive urine/serum pregnancy test in woman/women of childbearing potential (WOCBP) at Day -1
• Current use of any prohibited concomitant medication(s) for sisunatovir and/or medication(s) that are contraindicated in the rabeprazole prescribing information.
• Use of tobacco/nicotine containing products
• Screening supine blood pressure (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.
• Renal impairment as defined by an estimated glomerular filtration rate (eGFR) (units of mL/min/1.73m²) \<60 mL/min(/1.73m²) based on 2021 chronic kidney disease epidemiology (CKD-EPI).
• Standard 12-lead ECG that demonstrates clinically relevant abnormalities that may affect participant safety or interpretation of study results
• Alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin (Bili) ≥ 1.05 × upper limit of normal (ULN). Participants with an elevated total bilirubin consistent with Gilbert's Disease should have a direct bilirubin measured and would be eligible for this study provided the direct bilirubin level is ≤ ULN.

Sponsors & Collaborators

• Pfizer: lead

Study Sites (1)

Pfizer Clinical Research Unit - Brussels

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

Location

Related Links

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

MeSH Terms

Interventions

sisunatovir; Rabeprazole

Intervention Hierarchy (Ancestors)

2-Pyridinylmethylsulfinylbenzimidazoles; Sulfoxides; Sulfur Compounds; Organic Chemicals; Pyridines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Benzimidazoles; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring

Study Officials

• Pfizer CT.gov Call Center

  Pfizer

  STUDY DIRECTOR

Study Design

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

Study Record Dates

• First Submitted: October 24, 2023
• First Posted: October 30, 2023
• Study Start: November 3, 2023
• Primary Completion: July 19, 2024
• Study Completion: July 19, 2024
• Last Updated: April 24, 2025

Record last verified: 2025-04

Data Sharing

• IPD Sharing: Will not share

Locations

BE (1)