Study to Evaluate the Pharmacokinetics of Firsocostat or Fenofibrate in Adults With Normal and Impaired Hepatic Function

Study Overview
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Brief Summary
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The primary objectives of this study are to evaluate the single-dose pharmacokinetics (PK) of firsocostat in adults with normal hepatic function, and mild, moderate, or severe hepatic impairment and to evaluate the single-dose PK of fenofibrate in adults with normal hepatic function and mild hepatic impairment.

Official Title
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A Phase 1 Open-Label, Parallel-Group, Single-Dose Study to Evaluate the Pharmacokinetics of GS-0976 or Fenofibrate in Subjects With Normal and Impaired Hepatic Function

Conditions
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Nonalcoholic Steatohepatitis (NASH)

Intervention / Treatment
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* Drug: Firsocostat
* Drug: Fenofibrate


Participation Criteria
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Eligibility Criteria
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Key Inclusion Criteria: Cohort 1 (Mild Hepatic Impairment): Male and non-pregnant/non-lactating females with mildly impaired and normal hepatic function. Individuals will be current non-smokers (no use of tobacco, nicotine-containing or tetrahydrocannabinol (THC)-containing products within the last 14 days). Each individual in the control group will be matched for age (± 10 years), gender, race, and body mass index (± 15% 18 ≤ body mass index (BMI) ≤ 36 kg/m^2) with an individual in the mild hepatic impairment group. Individuals with mild hepatic impairment must have a score of 5-6 on the Child-Pugh-Turcotte (CPT) Classification at screening, have diagnosis of chronic (> 6 months), and stable hepatic impairment with no clinically significant changes within 3 months (or 90 days) prior to study drug administration (Day 1). Cohort 2 (Moderate Hepatic Impairment): Male and non-pregnant/non-lactating females with moderately impaired and normal hepatic function. Individuals will be current non-smokers (no smoking of tobacco, nicotine-containing or THC-containing products within the last 14 days). Each individual in the control group will be matched for age (± 10 years), gender, race, and body mass index (± 15% 18 ≤ BMI ≤ 36 kg/m^2) with an individual in the moderate hepatic impairment group. Individuals with moderate hepatic impairment must have a score of 7-9 on the CPT Classification at screening, have diagnosis of chronic (> 6 months), and stable hepatic impairment with no clinically significant changes within 3 months (or 90 days) prior to study drug administration (Day 1). Cohort 3 (Severe Hepatic Impairment): Male and nonpregnant/non-lactating females with severely impaired and normal hepatic function. Individuals will be current non-smokers (no use of tobacco, nicotine-containing or THC-containing products within the last 14 days). Each individual in the control group will be matched for age (± 10 years), gender, race, and body mass index (± 15% 18 ≤ BMI ≤ 36 kg/m^2) with an individual in the severe hepatic impairment group. Individuals with severe hepatic impairment must have a score of 10-15 on the CPT Classification at screening, have diagnosis of chronic (> 6 months), and stable hepatic impairment with no clinically significant changes within 3 months (or 90 days) prior to study drug administration (Day 1). Cohort 4 (Mild Hepatic Impairment): Male and non-pregnant/non-lactating females with mildly impaired and normal hepatic function. Individuals will be current non-smokers (no use of tobacco, nicotine-containing or THC-containing products within the last 14 days). Each individual in the control group will be matched for age (± 10 years), gender, race, and body mass index (± 15% 18 ≤ body mass index (BMI) ≤ 36 kg/m^2) with an individual in the mild hepatic impairment group. Individuals with mild hepatic impairment must have a score of 5-6 on the Child-Pugh-Turcotte (CPT) Classification at screening, have diagnosis of chronic (> 6 months), and stable hepatic impairment with no clinically significant changes within 3 months (or 90 days) prior to study drug administration (Day 1). NOTE: Other protocol defined Inclusion/ Exclusion criteria may apply.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Cohort 1 (Mild Hepatic Impairment): Firsocostat 20 mg<br>Participants with mild hepatic impairment will receive a single dose of firsocostat 20 mg (2 × 10 mg capsules). | Drug: Firsocostat<br>* Capsule(s) administered orally on Day 1<br>* Other names: GS-0976;|
| Experimental: Cohort 1 (Normal Hepatic Function): Firsocostat 20 mg<br>Matched normal hepatic function participants to mild hepatic impairment participants will receive a single dose of firsocostat 20 mg (2 × 10 mg capsules). | Drug: Firsocostat<br>* Capsule(s) administered orally on Day 1<br>* Other names: GS-0976;|
| Experimental: Cohort 2 (Moderate Hepatic Impairment): Firsocostat 20 mg<br>Participants with moderate hepatic impairment will receive a single dose of firsocostat 20 mg (2 × 10 mg capsules). | Drug: Firsocostat<br>* Capsule(s) administered orally on Day 1<br>* Other names: GS-0976;|
| Experimental: Cohort 2 (Normal Hepatic Function): Firsocostat 20 mg<br>Matched normal hepatic function participants to moderate hepatic impairment participants will receive a single dose of firsocostat 20 mg (2 × 10 mg capsules). | Drug: Firsocostat<br>* Capsule(s) administered orally on Day 1<br>* Other names: GS-0976;|
| Experimental: Cohort 3 (Severe Hepatic Impairment): Firsocostat 5 mg<br>Participants with severe hepatic impairment will receive a single dose of firsocostat 5 mg (1 × 5 mg capsule). | Drug: Firsocostat<br>* Capsule(s) administered orally on Day 1<br>* Other names: GS-0976;|
| Experimental: Cohort 3 (Normal Hepatic Function) Firsocostat 5 mg<br>Matched normal hepatic function participants to severe hepatic impairment participants will receive a single dose of firsocostat 5 mg (1 × 5 mg capsule). | Drug: Firsocostat<br>* Capsule(s) administered orally on Day 1<br>* Other names: GS-0976;|
| Experimental: Cohort 4 (Mild Hepatic Impairment): Fenofibrate 48 mg<br>Participants with mild hepatic impairment will receive a single dose of fenofibrate 48 mg (1 × 48 mg tablet). | Drug: Fenofibrate<br>* Tablet administered orally on Day 1<br>|
| Experimental: Cohort 4 (Normal Hepatic Function) Fenofibrate 48 mg<br>Matched normal hepatic function participants to mild hepatic impairment participants, will receive a single dose of fenofibrate 48 mg (1 × 48 mg tablet). | Drug: Fenofibrate<br>* Tablet administered orally on Day 1<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pharmacokinetic (PK) Parameter: AUClast of Firsocostat, GS-834773 (Primary Metabolite of Firsocostat), and Fenofibric Acid (Primary Metabolite of Fenofibrate) | AUClast is defined as the concentration of drug from time zero to the last observable concentration. The PK of fenofibric acid was evaluated in participants with mild hepatic impairment and matched participants with normal hepatic function (Cohort 4). | Day 1: 0 (predose, ≤ 5 minutes prior to dosing), 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 16, 24, 48, 72, and 96 hours postdose; or 72 hours of early termination from the study (if applicable) | 
| PK Parameter: AUCinf of Firsocostat, GS-834773 (Primary Metabolite of Firsocostat), and Fenofibric Acid (Primary Metabolite of Fenofibrate) | AUCinf is defined as the concentration of drug extrapolated to infinite time. The PK of fenofibric acid was evaluated in participants with mild hepatic impairment and matched participants with normal hepatic function (Cohort 4). | Day 1: 0 (predose, ≤ 5 minutes prior to dosing), 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 16, 24, 48, 72, and 96 hours postdose; or 72 hours of early termination from the study (if applicable) | 
| PK Parameter: Cmax of Firsocostat, GS-834773 (Primary Metabolite of Firsocostat), and Fenofibric Acid (Primary Metabolite of Fenofibrate) | Cmax is defined as the maximum observed concentration of drug. The PK of fenofibric acid was evaluated in participants with mild hepatic impairment and matched participants with normal hepatic function (Cohort 4). | Day 1: 0 (predose, ≤ 5 minutes prior to dosing), 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 16, 24, 48, 72, and 96 hours postdose; or 72 hours of early termination from the study (if applicable) | 
| PK Parameter: % AUCexp of Firsocostat, GS-834773 (Primary Metabolite of Firsocostat), and Fenofibric Acid (Primary Metabolite of Fenofibrate) | %AUCexp is defined as the percentage of AUC extrapolated between AUClast and AUCinf. The PK of fenofibric acid was evaluated in participants with mild hepatic impairment and matched participants with normal hepatic function (Cohort 4). | Day 1: 0 (predose, ≤ 5 minutes prior to dosing), 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 16, 24, 48, 72, and 96 hours postdose; or 72 hours of early termination from the study (if applicable) | 
| PK Parameter: Tmax of Firsocostat, GS-834773 (Primary Metabolite of Firsocostat), and Fenofibric Acid (Primary Metabolite of Fenofibrate) | Tmax is defined as the time (observed time point) of Cmax. The PK of fenofibric acid was evaluated in participants with mild hepatic impairment and matched participants with normal hepatic function (Cohort 4). | Day 1: 0 (predose, ≤ 5 minutes prior to dosing), 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 16, 24, 48, 72, and 96 hours postdose; or 72 hours of early termination from the study (if applicable) | 
| PK Parameter: Clast of Firsocostat, GS-834773 (Primary Metabolite of Firsocostat), and Fenofibric Acid (Primary Metabolite of Fenofibrate) | Clast is defined as the last observed quantifiable concentration of drug. The PK of fenofibric acid was evaluated in participants with mild hepatic impairment and matched participants with normal hepatic function (Cohort 4). | Day 1: 0 (predose, ≤ 5 minutes prior to dosing), 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 16, 24, 48, 72, and 96 hours postdose; or 72 hours of early termination from the study (if applicable) | 
| PK Parameter: Tlast of Firsocostat, GS-834773 (Primary Metabolite of Firsocostat), and Fenofibric Acid (Primary Metabolite of Fenofibrate) | Tlast is defined as the time (observed time point) of Clast. The PK of fenofibric acid was evaluated in participants with mild hepatic impairment and matched participants with normal hepatic function (Cohort 4). | Day 1: 0 (predose, ≤ 5 minutes prior to dosing), 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 16, 24, 48, 72, and 96 hours postdose; or 72 hours of early termination from the study (if applicable) | 
| PK Parameter: λz of Firsocostat, GS-834773 (Primary Metabolite of Firsocostat), and Fenofibric Acid (Primary Metabolite of Fenofibrate) | λz is defined as the terminal elimination rate constant, estimated by linear regression of the terminal elimination phase of the log plasma concentration of drug versus time curve of the drug. The PK of fenofibric acid was evaluated in participants with mild hepatic impairment and matched participants with normal hepatic function (Cohort 4). | Day 1: 0 (predose, ≤ 5 minutes prior to dosing), 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 16, 24, 48, 72, and 96 hours postdose; or 72 hours of early termination from the study (if applicable) | 
| PK Parameter: CL/F of Firsocostat, GS-834773 (Primary Metabolite of Firsocostat), and Fenofibric Acid (Primary Metabolite of Fenofibrate) | CL/F is defined as the apparent oral clearance following administration of the drug. The PK of fenofibric acid was evaluated in participants with mild hepatic impairment and matched participants with normal hepatic function (Cohort 4). | Day 1: 0 (predose, ≤ 5 minutes prior to dosing), 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 16, 24, 48, 72, and 96 hours postdose; or 72 hours of early termination from the study (if applicable) | 
| PK Parameter: Vz/F of Firsocostat, GS-834773 (Primary Metabolite of Firsocostat), and Fenofibric Acid (Primary Metabolite of Fenofibrate) | Vz/F is defined as the apparent volume of distribution of the drug. The PK of fenofibric acid was evaluated in participants with mild hepatic impairment and matched participants with normal hepatic function (Cohort 4). | Day 1: 0 (predose, ≤ 5 minutes prior to dosing), 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 16, 24, 48, 72, and 96 hours postdose; or 72 hours of early termination from the study (if applicable) | 
| PK Parameter: t1/2 of Firsocostat, GS-834773 (Primary Metabolite of Firsocostat), and Fenofibric Acid (Primary Metabolite of Fenofibrate) | t1/2 is defined as the estimate of the terminal elimination half-life of the drug. The PK of fenofibric acid was evaluated in participants with mild hepatic impairment and matched participants with normal hepatic function (Cohort 4). | Day 1: 0 (predose, ≤ 5 minutes prior to dosing), 0.5, 1, 2, 3, 4, 6, 8, 10, 12, 16, 24, 48, 72, and 96 hours postdose; or 72 hours of early termination from the study (if applicable) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants Experiencing Treatment-Emergent Adverse Events (AEs) | Treatment-emergent adverse events (TEAEs) were defined as 1 or both of the following: Any AEs with an onset date on or after the study drug start date and no later than 30 days after permanent discontinuation of study drug. If the AE onset date is the same as the date of study drug start date then the AE onset time must be on or after the study drug start time. If the AE onset time is missing when the start dates are the same, the AE will be considered treatment emergent. Any AEs leading to premature discontinuation of study drug. | First dose date plus 30 days | 
| Percentage of Participants Experiencing Laboratory Abnormalities | Treatment-emergent laboratory abnormalities are defined as values that increase at least 1 toxicity grade from predose at any postdose visit, up to and including the date of last dose of study drug plus 30 days for subjects who permanently discontinued study drug. The most severe graded abnormality from all tests was counted for each participant. | First dose date plus 30 days |