A Study to Compare How the Study Medicine (PF-07923568) is Processed in Participants With Different Levels of Loss of Liver Function to Healthy Participants.

A PHASE 1, OPEN-LABEL, SINGLE-DOSE, PARALLEL GROUP STUDY TO COMPARE THE PHARMACOKINETICS OF PF-07923568 IN ADULT PARTICIPANTS WITH VARYING DEGREES OF HEPATIC IMPAIRMENT RELATIVE TO PARTICIPANTS WITHOUT HEPATIC IMPAIRMENT

The purpose of this study is to learn how the study medicine (PF-07923568) is processed in participants with liver function loss compared to healthy participants. The different levels of liver function loss can be mild, moderate or severe.

This study is seeking participants who:

• are male or female of 18 years of age or older.
• are examined to be healthy (group with no loss of liver function).
• have mild, moderate, and severe liver disease (group with loss of liver function).

All participants will receive a one-time dose of 4 capsules of PF-07923568 which will be taken by mouth. All participants will remain at the study clinic for 6 days for safety review and laboratory collections. This is to see how the study medicine is being broken down by the liver over time.

All participants selected in the study will be required to go through a screening period up to 28 days. A screening period is the time during which a few participants are examined to see whether they are fit for the study. During this period, the participant's medical history and past and current medications will be reviewed. A series of tests will also be performed to see if they are good to be selected for the study. If the participant meets all required criteria and are interested in continuing, the participant will be brought into the study clinic to stay overnight for 6 days. On day 6, the participant will be discharged. About 28 to 35 days after discharge, the participant will be contacted for a follow up visit either in person or by telephone. This is to check up on how the participant is doing and to conclude the study.

Study Overview

• Status: Completed
• Conditions: Liver Diseases; Hepatic Impairment
• Intervention / Treatment: Drug: PF-07923568

• Study Type: Interventional
• Enrollment (Actual): 28
• Phase: Phase 1

Contacts and Locations

Study Locations

• United States
  • California
    • Tustin, California, United States, 92780
      • Orange County Research Center
  • Florida
    • Orlando, Florida, United States, 32809
      • Orlando Clinical Research Center
    • Tampa, Florida, United States, 33603
      • Genesis Clinical Research, LLC

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria: for healthy volunteers:

• BMI of 17.5 to 38.0 kg/m2, inclusive, and a total body weight >50 kg (110 lb).
• Capable of giving signed informed consent.
• At screening, no clinically relevant abnormalities identified by a detailed medical history, complete physical examination, including BP and pulse rate measurement, standard 12-lead ECG and clinical laboratory tests.

• body weight within +/-15 kg of the average of pooled hepatic impaired group and +/- 10 years of the average pooled hepatic impairment group.

  --Exclusion criteria for all participants:

• Any condition or surgery possibly affecting drug absorption (eg, prior bariatric surgery, gastrectomy, ileal resection)
• Positive HIV antibodies
• Positive drug or alcohol test eGFR <60 mL/min/1.73m2 at screening

Exclusion criteria for non-healthy participants who have hepatic impairment:

• Stable concomitant meds and hepatic impairment with no change in the last 28 days
• Hepatic carcinoma or hepatorenal syndrome or limited predicted life expectancy (defined as <1 year).
• A diagnosis of hepatic dysfunction secondary to any acute ongoing hepatocellular process that is documented by medical history, PE, liver biopsy, hepatic ultrasound, CT scan, or MRI.

• History of gastrointestinal hemorrhage due to esophageal varices or peptic ulcers less than 4 weeks prior to screening.

  --Severe ascites and/or pleural effusion, except for those categorized as severe hepatic impairment who may be enrolled provided participant is medically stable, per the investigators' medical judgment.

• Previously received a kidney, liver, or heart transplant. ALT/AST greater than 5X upper limit normal

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Healthy subjects; One time dose of 4 capsules taken orally.	Drug: PF-07923568; One time dose of 4 capsules taken orally.; Other Names: Sisunatovir
Experimental: Mild Hepatic impaired subjects; One time dose of 4 capsules taken orally.	Drug: PF-07923568; One time dose of 4 capsules taken orally.; Other Names: Sisunatovir
Experimental: Moderate hepatic impaired subjects; One time dose of 4 capsules taken orally	Drug: PF-07923568; One time dose of 4 capsules taken orally.; Other Names: Sisunatovir
Experimental: Severe Hepatic Impaired Subjects; One time dose of 4 capsules taken orally.	Drug: PF-07923568; One time dose of 4 capsules taken orally.; Other Names: Sisunatovir

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Plasma Maximum Concentration (Cmax) of Sisunatovir Following Administration of a Single Oral Dose	Cmax was the highest concentration observed directly from data	Hours 0, 1, 2, 3, 4, 5, 6, 8, 12, 24, 48, 72, 96, and 120 postdose from Day 1 to Day 6
Area Under the Plasma Concentration-time Profile From Time Zero to the Time of the Last Quantifiable Concentration (AUClast) of Sisunatovir Following Administration of a Single Oral Dose	AUClast was determined using linear/Log trapezoidal method	Hours 0, 1, 2, 3, 4, 5, 6, 8, 12, 24, 48, 72, 96, and 120 postdose from Day 1 to Day 6
Area Under the Plasma Concentration-time Profile From Time Zero Extrapolated to Infinite Time (AUCinf) of Sisunatovir Following Administration of a Single Oral Dose	AUClast + (Clast*/kel), where Clast* was the predicted plasma concentration at the last quantifiable time point estimated from the log-linear regression analysis and kel was the terminalphase rate constant.	Hours 0, 1, 2, 3, 4, 5, 6, 8, 12, 24, 48, 72, 96, and 120 postdose from Day 1 to Day 6

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants With All-causality Treatment-emergent Adverse Events (TEAEs), Serious TEAEs, Treatment-related TEAEs, and Discontinuations From Study Due to TEAEs	Adverse event (AE) was any untoward medical occurrence in the participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. Serious AE was any untoward medical occurrence that resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent disability/incapacity, was a congenital anomaly/birth defect, or was considered to be an important medical event. Any events occurring following start of treatment or increasing in severity were counted as treatment-emergent. AEs included both serious and non-serious AEs.	Day -1 through follow-up (Day 29-36)
Number of Participants With Laboratory Test Abnormalities	Laboratory test included: hematology (hemoglobin, hematocrit, red blood cell count, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, platelet count, white blood cell count, absolute and percent total neutrophils, eosinophils, monocytes, basophils and lymphocytes), chemistry (blood urea nitrogen/urea and creatinine, fasting glucose, calcium, sodium, potassium, chloride, total carbon dioxide, aspartate aminotransferase, alanine aminotransferase, total bilirubin, alkaline phosphatase, uric acid, albumin and total protein), urinalysis (pH, qualitative glucose, qualitative protein, qualitative blood, ketones, nitrites, leukocyte esterase, urobilinogen, urine bilirubin, microscopy, urinary albumin to creatinine ratio and urinary protein to creatinine ratio) and other tests. Abnormality was determined by the investigator. Only lab abnormalities with at least 1 occurrence in participants are reported.	Day -1 and Day 6
Number of Participants With Vital Signs Meeting Categorical Criteria	Supine blood pressure and pulse rate were measured. Categorical classes for vital signs of potential clinical concerns were defined as followed: systolic blood pressure (SBP) <90 millimeters of mercury (mmHg); diastolic blood pressure (DBP) <50 mmHg; pulse rate <40 beats per minute (bpm); pulse rate >120 bpm, and increase from baseline in SBP ≥30 mmHg; decrease from baseline in SBP ≥30 mmHg; increase from baseline in DBP ≥20 mmHg; decrease from baseline in DBP ≥20 mmHg. The baseline measurement was the predose measurement on Day 1. Changes from baseline was defined as the change between the postdose and baseline measurements.	Day -1, Day 1, Day 2, and Day 6
Number of Participants With Electrocardiograms (ECGs) Meeting Categorical Criteria	Number of participants with ECG findings meeting the following criteria: time between the onset of atrial depolarization and onset of ventricular depolarization (PR interval) ≥300 msec; time from ECG Q-wave to the end of the S wave corresponding to ventricular depolarization (QRS duration) ≥140 msec; correct time from ECG Q-wave to the end of the T wave corresponding to electrical systole for heart rate using Fridericia's formula (QTcF interval): ≥450 to <480 msec; QTcF interval ≥480 to <500 msec; QTcF interval: ≥500 msec; PR interval percent change from baseline (≥25/50%): ≥25% if baseline >200 msec or ≥ 50% if baseline ≤200 msec; QRS duration percent change from baseline ≥50%; QTcF interval change from baseline: >30 to ≤60 msec; QTcF interval change from baseline >60 msec. The baseline measurement was the predose measurement on Day 1. Changes from baseline was defined as the change between the postdose and baseline measurements.	Day -1, Day 1, Day 2, and Day 6

Collaborators and Investigators

• Sponsor: Pfizer
• Investigators: Study Director: Pfizer CT.gov Call Center, Pfizer

Publications and helpful links

Helpful Links

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

Study record dates

Study Major Dates

• Study Start (Actual): June 7, 2023
• Primary Completion (Actual): February 7, 2024
• Study Completion (Actual): February 7, 2024

Study Registration Dates

• First Submitted: April 6, 2023
• First Submitted That Met QC Criteria: May 4, 2023
• First Posted (Actual): May 12, 2023

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: March 4, 2025
• Last Verified: March 1, 2025

More Information

Terms related to this study

• Keywords: healthy volunteers
• Additional Relevant MeSH Terms: Digestive System Diseases; Liver Diseases
• Other Study ID Numbers: C5241012; NCT05857644 (Registry Identifier: ClinicalTrials.gov)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: 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.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No