Cohort 1 and 2: The primary objectives of this study are: Part A: - To evaluate the steady state pharmacokinetics (PK) of bictegravir (BIC) and confirm the dose of the bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) 50/200/25 mg fixed dose combination (FDC) in HIV-1 infected, virologically suppressed adolescents (12 to < 18 years of age) and children (6 to < 12 years of age) Parts A and B: - To evaluate the safety and tolerability of the adult strength B/F/TAF FDC through Week 24 in HIV-1 infected, virologically suppressed adolescents (12 to <18 years of age) and children (6 to <12 years of age) Cohort 3: The primary objectives of this study are: Part A: - To evaluate the steady state PK of BIC and confirm the dose of B/F/TAF 30/120/15 mg FDC in HIV-1 infected, virologically suppressed children ≥ 2 years of age weighing ≥ 14 to < 25 kg Parts A and B: - To evaluate the safety and tolerability of the low dose B/F/TAF FDC tablet through Week 24 in HIV-1 infected, virologically suppressed children ≥ 2 years of age weighing ≥ 14 to < 25 kg
Name: B/F/TAF (Adult Strength)
Name: B/F/TAF (Low Dose)
Description: AUCtau is defined as concentration of drug over time (the area under the concentration verses time curve over the dosing interval).
Measure: PK Parameter: AUCtau of Bictegravir Time: Week 2 (all Cohorts) or Week 4 (Cohort 1 and Cohort 2 Part A participants only)Description: Ctau is defined as the observed drug concentration at the end of the dosing interval.
Measure: PK Parameter: Ctau of Bictegravir Time: Week 2 (all Cohorts) or Week 4 (Cohort 1 and Cohort 2 Part A participants only)Description: Tmax is defined as the time (observed time point) of Cmax.
Measure: PK Parameter: Tmax of Bictegravir Time: Week 2 or Week 4Description: Cmax is defined as the maximum observed concentration of drug.
Measure: PK Parameter: Cmax of Bictegravir Time: Week 2 or Week 4Description: AUClast is defined as the concentration of drug from time zero to the last observable concentration.
Measure: PK Parameter: AUClast of Bictegravir Time: Week 2 or Week 4Description: T1/2 is defined as the estimate of the terminal elimination half-life of the drug.
Measure: PK Parameter: T1/2 of Bictegravir Time: Week 2 or Week 4Description: CL is defined as the systemic clearance of the drug following study drug administration.
Measure: PK Parameter: Apparent Clearance (CL) of Bictegravir Time: Week 2 or Week 4Description: Vz is defined as the volume of distribution of the drug after study drug administration.
Measure: PK Parameter: Apparent Vz of Bictegravir Time: Week 2 or Week 4Description: AUCtau is defined as concentration of drug over time (the area under the concentration verses time curve over the dosing interval).
Measure: PK Parameter: AUCtau of TAF and FTC Time: Week 2 or Week 4Description: AUClast is defined as the concentration of drug from time zero to the last observable concentration.
Measure: PK Parameter: AUClast of TAF and FTC Time: Week 2 or Week 4Description: Cmax is defined as the maximum observed concentration of drug.
Measure: PK Parameter: Cmax of TAF and FTC Time: Week 2 or Week 4Description: Ctau is defined as the observed drug concentration at the end of the dosing interval.
Measure: PK Parameter: Ctau of TAF and FTC Time: Week 2 or Week 4Description: Tmax is defined as the time (observed time point) of Cmax.
Measure: PK Parameter: Tmax of TAF and FTC Time: Week 2 or Week 4Description: T1/2 is defined as the estimate of the terminal elimination half-life of the drug.
Measure: PK Parameter: T1/2 of TAF and FTC Time: Week 2 or Week 4Description: CL is defined as the systemic clearance of the drug following study drug administration.
Measure: PK Parameter: Apparent CL of TAF and FTC Time: Week 2 or Week 4Description: Vz is defined as the volume of distribution of the drug after study drug administration.
Measure: PK Parameter: Apparent Vz of TAF and FTC Time: Week 2 or Week 4Description: Participants will be asked if the study drug was palatable and if they were able to take the dosage form.
Measure: Acceptability and Palatability of B/F/TAF Formulation at Day 1 (All Cohorts) Time: Day 1Description: Participants will be asked if the study drug was palatable and if they were able to take the dosage form.
Measure: Acceptability and Palatability of B/F/TAF Formulation at Week 4 (All Cohorts) Time: Week 4Description: Participants will be asked if the study drug was palatable and if they were able to take the dosage form.
Measure: Acceptability and Palatability of B/F/TAF Formulation at Week 24 (Cohort 3) Time: Week 24Description: Participants will be asked if the study drug was palatable and if they were able to take the dosage form.
Measure: Acceptability and Palatability of B/F/TAF Formulation at Week 48 (Cohort 3) Time: Week 48Allocation: Non-Randomized
Single Group Assignment
There are 2 SNPs
m^2 according to the Schwartz Formula - No documented or suspected resistance to emtricitabine (FTC), tenofovir (TFV), or integrase strand transfer inhibitors (INSTIs) including, but not limited to, the reverse transcriptase resistance mutations K65R and M184V/I Note: Other protocol defined Inclusion/Exclusion criteria may apply. --- K65R ---
m^2 according to the Schwartz Formula - No documented or suspected resistance to emtricitabine (FTC), tenofovir (TFV), or integrase strand transfer inhibitors (INSTIs) including, but not limited to, the reverse transcriptase resistance mutations K65R and M184V/I Note: Other protocol defined Inclusion/Exclusion criteria may apply. --- K65R --- --- M184V ---