A Study to Evaluate the Pharmacokinetics, Safety, and Efficacy of Glecaprevir/Pibrentasvir in Pediatric Subjects With Genotypes 1-6 Chronic Hepatitis C Virus (HCV) Infection

Overview

The objectives of this study are to assess the pharmacokinetics, safety, and efficacy of glecaprevir/pibrentasvir adult formulation in adolescents ages 12 to 17 years and a pediatric formulation of glecaprevir and pibrentasvir in children ages 3 to < 12 years.

Full Title of Study: “An Open-Label, Multicenter Study to Evaluate the Pharmacokinetics, Safety, and Efficacy of Glecaprevir/Pibrentasvir in Pediatric Subjects With Genotypes 1-6 Chronic Hepatitis C Virus (HCV) Infection”

Study Type

• Study Type: Interventional
• Study Design
  • Allocation: Non-Randomized
  • Intervention Model: Parallel Assignment
  • Primary Purpose: Treatment
  • Masking: None (Open Label)
• Study Primary Completion Date: May 21, 2020

Detailed Description

This was a multicenter study to evaluate the pharmacokinetics (PK), efficacy, and safety of glecaprevir (GLE) and pibrentasvir (PIB) treatment for 8, 12, or 16 weeks in hepatitis C virus (HCV) genotype 1 – 6 (GT1 – GT6)-infected pediatric participants 3 to < 18 years of age, with or without compensated cirrhosis, with or without human immunodeficiency virus (HIV) coinfection, who are either treatment-naïve (TN), treatment-experienced (TE) with pegylated interferon (pegIFN) with or without ribavirin (RBV), or TE with sofosbuvir (SOF) + RBV with or without pegIFN. The study was divided into 2 parts, according to the formulation of GLE/PIB administered. Part 1 of the study enrolled HCV GT1 – GT6 infected adolescent participants into the 12 to < 18 years old age group who were willing to swallow the adult formulation of GLE/PIB (Cohort 1). Part 2 of the study enrolled HCV GT1 – GT6 infected pediatric participants divided into the 9 to < 12 (Cohort 2), 6 to < 9 (Cohort 3), and 3 to < 6 (Cohort 4) years old age groups, to receive the pediatric formulation of GLE + PIB. Part 1 enrolled first and once the pediatric formulation was available enrollment into Part 2 commenced, with each cohort enrolled in parallel. In each cohort, the first group of participants were enrolled into an intense pharmacokinetics (IPK) portion to characterize the PK and safety in each age group, followed by enrollment into a non-IPK safety/efficacy portion. Study participants enrolled in the IPK portion must have been HIV-negative, treatment-naive, and have an identified HCV genotype. In the IPK portion the first approximately six participants received an initial proposed dose of GLE and PIB based on the child's weight and age at screening. PK samples from these participants were evaluated to determine if therapeutic efficacious exposures were attained, comparable to those of adults, and if any dose adjustments were needed. After the intensive PK analysis results for the first six participants were available, enrollment of the remaining IPK portion resumed with subsequent participants receiving an adjusted final dose as applicable. Additional participants may have been required for further intensive PK analysis per age cohort if therapeutic exposure targets were not achieved. Enrollment into the non-IPK safety and efficacy portions began when the dosing recommendations per age group based on the PK and clinical data from the IPK analysis were ascertained.

Interventions

• Drug: Glecaprevir/Pibrentasvir Adult Formulation
  • Co-formulated film-coated tablet (100 mg/40 mg)
• Drug: Glecaprevir + Pibrentasvir Pediatric Formulation
  • Film-coated pellets/granules (15.67%/8.25%) administered by mixing with a small amount (1-2 teaspoons) of a soft food vehicle, such as hazelnut spread, Greek yogurt, or peanut butter.

Arms, Groups and Cohorts

• Experimental: Cohort 1: Adult Formulation; 12 to < 18 years
  • Adolescents aged 12 to < 18 years old received the adult formulation of glecaprevir (GLE)/pibrentasvir (PIB) 100 mg/ 40 mg co-formulated film-coated tablets for a once daily (QD) total dose of 300 mg/120 mg by mouth for 8, 12, or 16 weeks depending on HCV genotype, cirrhosis status, and prior treatment experience.
• Experimental: Cohort 2: Pediatric Formulation; 9 to < 12 years
  • Children aged 9 to < 12 years old received a pediatric formulation of GLE + PIB as small film-coated granules taken with a small amount of food once daily for 8, 12, or 16 weeks depending on HCV genotype, cirrhosis status, and prior treatment experience. The initial proposed dose for children 9 to < 12 years old (30 to < 45 kg) was GLE 200 mg + PIB 75 mg. After PK analysis from the first 6 enrolled participants the dose was adjusted to GLE 250 mg + PIB 100 mg.
• Experimental: Cohort 3: Pediatric Formulation; 6 to < 9 years
  • Children aged 6 to < 9 years old received a pediatric formulation of GLE + PIB as small film-coated granules taken with a small amount of food once daily for 8, 12, or 16 weeks depending on HCV genotype, cirrhosis status, and prior treatment experience. The initial proposed dose for children 6 to < 9 years old (20 to < 30 kg) was GLE 160 mg + PIB 60 mg. After PK analysis from the first 6 enrolled participants the dose was adjusted to GLE 200 mg + PIB 80 mg.
• Experimental: Cohort 4: Pediatric Formulation; 3 to < 6 years
  • Children aged 3 to < 6 years old received a pediatric formulation of GLE + PIB as small film-coated granules taken with a small amount of food once daily for 8, 12, or 16 weeks depending on HCV genotype, cirrhosis status, and prior treatment experience. The initial proposed dose for children 3 to < 6 years old (12 to < 20 kg) was GLE 120 mg + PIB 45 mg. After PK analysis from the first 5 enrolled participants the dose was adjusted to GLE 150 mg + PIB 60 mg.

Clinical Trial Outcome Measures

Primary Measures

• Steady-state Area Under the Plasma Concentration-time Curve From Time Zero to 24 Hours Postdose (AUC0-24) of Glecaprevir
  • Time Frame: Week 2 from predose to 24 hours post-dose
  • The area under the plasma concentration-time curve (AUC) is a method of measurement of the total exposure of a drug in blood plasma. The steady-state exposure of GLE was measured up to 24 hours after dosing at Week 2 and estimated using non-compartmental analysis.
• Steady-state AUC0-24 of Pibrentasvir
  • Time Frame: Week 2 from predose to 24 hours post-dose
  • The area under the plasma concentration-time curve (AUC) is a method of measurement of the total exposure of a drug in blood plasma. The steady-state exposure of PIB was measured up to 24 hours after dosing at Week 2 and estimated using non-compartmental analysis.
• Percentage of Participants With Sustained Virologic Response 12 Weeks Post Treatment (SVR12)
  • Time Frame: 12 weeks after last dose of study drug (Week 20, 24, or 28 depending on treatment duration)
  • SVR12 is defined as hepatitis C virus ribonucleic acid (HCV RNA) less than the lower limit of quantification (LLOQ; 15 IU/mL) 12 weeks after the last actual dose of study drug. Plasma HCV RNA levels were collected using the COBAS AmpliPrep/COBAS TaqMan HCV Quantitative Test v2.0. SVR12 was considered a primary efficacy endpoint by the United States (US) regulatory agency and was considered secondary outside of the US.

Secondary Measures

• Maximum Plasma Concentration (Cmax) of Glecaprevir
  • Time Frame: Week 2 from predose to 24 hours post-dose
  • Cmax is the peak concentration that a drug or drug metabolite achieves in a specified compartment after the drug has been administered and before administration of a second dose.
• Apparent Clearance (CL/F) of Glecaprevir From Plasma
  • Time Frame: Week 2 from predose to 24 hours post-dose
  • CL/F is a quantitative measure of the rate at which a drug substance is removed from the body. It was estimated by non-compartmental pharmacokinetic analysis.
• Maximum Plasma Concentration of Pibrentasvir
  • Time Frame: Week 2 from predose to 24 hours post-dose
  • Cmax is the peak concentration that a drug or drug metabolite achieves in a specified compartment after the drug has been administered and before administration of a second dose.
• Apparent Clearance of Pibrentasvir From Plasma
  • Time Frame: Week 2 from predose to 24 hours post-dose
  • CL/F is a quantitative measure of the rate at which a drug substance is removed from the body. It was estimated by non-compartmental pharmacokinetic analysis.
• Percentage of Participants Who Experienced On-treatment Virologic Failure
  • Time Frame: Up to Week 8, 12, or 16 (depending on treatment duration)
  • On-treatment virologic failure is defined as meeting one of the following: A confirmed (defined as two consecutive HCV RNA measurements) increase of > 1 log₁₀ IU/mL above nadir during treatment; Confirmed HCV RNA ≥ 100 IU/mL after HCV RNA < 15 IU/mL during treatment; HCV RNA ≥ 15 IU/mL at the end of treatment with at least 6 weeks of treatment.
• Percentage of Participants With Post-treatment Relapse up to 12 Weeks Post Treatment
  • Time Frame: Up to 12 weeks after the last dose of study drug (Week 20, 24, or 28 depending on treatment duration)
  • Post-treatment relapse is defined as confirmed HCV RNA ≥ 15 IU/mL between the end of treatment and 12 weeks after the last dose of study drug among participants who completed treatment as planned with HCV RNA < 15 IU/mL at the end of treatment; excluding participants who had been shown to be re-infected.
• Percentage of Participants With New Hepatitis C Virus Infection (Reinfection)
  • Time Frame: From the end of treatment up to post-treatment Week 144
  • Reinfection is defined as confirmed HCV RNA ≥ 15 IU/mL in the post-treatment period in a participant who had HCV RNA < 15 IU/mL at the Final Treatment Visit, along with post-treatment detection of a different HCV genotype, subtype, or clade compared with Baseline, as determined by phylogenetic analysis of the nonstructural viral protein 3 (NS3) or NS5A, and/or NS5B gene sequences.
• Palatability Questionnaire Question 1: How Convenient or Inconvenient Was it to Prepare the Dose?
  • Time Frame: Final treatment visit (up to Week 8, 12, or 16, depending on treatment duration)
  • For each participant who received the pediatric formulation (Cohorts 2 – 4), the parent(s)/guardian(s) completed a Palatability Questionnaire to provide feedback on the perception of the dosage form. The Palatability Questionnaire included 6 questions related to the administration and ingestion of the pediatric GLE + PIB formulation. Question 1 “How Convenient or Inconvenient Was it to Prepare the Dose?” was answered as “very convenient”, “convenient”, “borderline”, “inconvenient”, or “very inconvenient”.
• Palatability Questionnaire Question 2: How Long Did it Typically Take for the Child to Take the Dose?
  • Time Frame: Final treatment visit (up to Week 8, 12, or 16, depending on duration of treatment)
  • For each participant who received the pediatric formulation (Cohorts 2 – 4), the parent(s)/guardian(s) completed a Palatability Questionnaire to provide feedback on the perception of the dosage form. The Palatability Questionnaire included 6 questions related to the administration and ingestion of the pediatric GLE + PIB formulation. Question 2 “How Long Did it Typically Take for the Child to Take the Dose?” was answered as “5 minutes or less”, “5 to 15 minutes”, “15 to 30 minutes”, or “more than 30 minutes”.
• Palatability Questionnaire Question 3: Were You Able to Successfully Administer the Whole Dose to the Child With 1 to 2 Teaspoons (5 to 10 mL) of Soft Food?
  • Time Frame: Final treatment visit (up to Week 8, 12, or 16, depending on treatment duration)
  • For each participant who received the pediatric formulation (Cohorts 2 – 4), the parent(s)/guardian(s) completed a Palatability Questionnaire to provide feedback on the perception of the dosage form. The Palatability Questionnaire included 6 questions related to the administration and ingestion of the pediatric GLE + PIB formulation. Question 3 “Were You Able to Successfully Administer the Whole Dose to the Child With 1 to 2 Teaspoons (5 to 10 mL) of Soft Food?” was answered as “Yes” or “No”.
• Palatability Questionnaire Question 4: Did You Experience Any Resistance When Feeding the Child the Medicine?
  • Time Frame: Final treatment visit (up to Week 8, 12, or 16 depending on treatment duration)
  • For each participant who received the pediatric formulation (Cohorts 2 – 4), the parent(s)/guardian(s) completed a Palatability Questionnaire to provide feedback on the perception of the dosage form. The Palatability Questionnaire included 6 questions related to the administration and ingestion of the pediatric GLE + PIB formulation. Question 4 “Did You Experience Any Resistance When Feeding the Child the Medicine?” was answered as “Yes” or “No”.
• Palatability Questionnaire Question 4a: Type of Feeding Resistance
  • Time Frame: Up to final treatment visit (up to Week 8, 12, or 16 depending on treatment duration)
  • For each participant who received the pediatric formulation (Cohorts 2 – 4), the parent(s)/guardian(s) completed a Palatability Questionnaire to provide feedback on the perception of the dosage form. The Palatability Questionnaire included 6 questions related to the administration and ingestion of the pediatric GLE + PIB formulation. Question 4a “Type of feeding resistance?” tracks feeding resistance experienced at any time during treatment, and was answered as “Did not like taste of medicine”, “Did not like texture of medicine”, “Did not like the soft food used”, “Did not like to swallow the amount of medicine”, or “Unrelated to the medicine”.
• Palatability Questionnaire Question 5: How Easy or Difficult Was it for the Child to Swallow the Medicine?
  • Time Frame: Final treatment visit (up to Week 8, 12, or 16, depending on treatment duration)
  • For each participant who received the pediatric formulation (Cohorts 2 – 4), the parent(s)/guardian(s) completed a Palatability Questionnaire to provide feedback on the perception of the dosage form. The Palatability Questionnaire included 6 questions related to the administration and ingestion of the pediatric GLE/PIB formulation. Question 5 “How Easy or Difficult Was it for the Child to Swallow the Medicine?” was answered as “very easy”, “easy”, “borderline”, “difficult”, or “very difficult.”

Participating in This Clinical Trial

Inclusion Criteria

• Hepatitis C virus (HCV) infection demonstrated by positive anti-HCV antibody (Ab) and HCV ribonucleic acid (RNA) greater than or equal to 1000 International Unit (IU)/mL – Subjects participating in the intense pharmacokinetic (IPK) part must have been HCV treatment-naive, with or without compensated cirrhosis (Child-Pugh A), human immunodeficiency virus type 1 (HIV-1) negative and must have had a Screening laboratory result indicating HCV genotype (GT) 1, 2, 3, 4, 5, or 6-infection. Exclusion Criteria:

• Females who were pregnant or breastfeeding – Positive test result for hepatitis B surface antigen (HbsAg) or positive test result for hepatitis B virus deoxyribonucleic acid (DNA) – Participants with other known liver diseases – Decompensated cirrhosis defined as: presence of ascites, history of variceal bleeding, lab values consistent with Child-Pugh class B or C cirrhosis

Gender Eligibility: All

Minimum Age: 3 Years

Maximum Age: 17 Years

Are Healthy Volunteers Accepted: No

Investigator Details

• Lead Sponsor
  • AbbVie
• Provider of Information About this Clinical Study
  • Sponsor
• Overall Official(s)
  • AbbVie Inc., Study Director, AbbVie