Relative Bioavailability Study of Two New Dolutegravir/Abacavir/Lamivudine Fixed Dose Combination Tablets

Dolutegravir (DTG, GSK1349572) is a next-generation integrase inhibitor (INI) currently in phase 3 clinical trials for human immunodeficiency virus (HIV). Fixed-dose combinations (FDCs) have greatly simplified the treatment of patients with HIV. While Atripla (an FDC of tenofovir (TDF), emtricitabine (FTC) and efavirenz (EFV)) has become the preferred first line regimen due in large part to its convenient presentation as a full treatment regimen in a single product, other options are needed. A fixed-dose combination of DTG/abacavir (ABC)/lamivudine (3TC) is one such opportunity.

This is a single-center, randomized, open-label, 3-period crossover study in healthy adult subjects to evaluate the single-dose relative bioavailability of two experimental oral DTG 50 mg/ABC 600 mg/3TC 300 mg FDC tablet formulations compared to co-administration of the separate tablet formulations (DTG 50 mg tablet and EPZICOM), with each dose administered in the fasted state. Approximately 18 subjects will be enrolled and randomized to one of 6 different treatment sequences. There will be a screening visit within 30 days prior to the first dose of study drug and a follow up visit within 7-14 days after the last dose. There will be a 7 day washout between doses in each treatment period.

The following PK parameters for DTG, ABC and 3TC will be measured: area under the concentration curve from time zero (pre-dose) extrapolated to infinite time (AUC(0-infinity)), Area under the concentration-time curve from time zero (pre-dose) to the time of the last quantifiable concentration (AUC (0-t)), maximum observed concentration (Cmax), lag time before observation of drug concentrations (tlag), time of occurrence of Cmax (tmax), terminal phase half-life (t½), apparent clearance following oral dosing (CL/F) and apparent terminal phase volume of distribution (Vz/F).


Study Type: Interventional
Allocation: Randomized
Endpoint Classification: Pharmacokinetics Study
Intervention Model: Crossover Assignment
Masking: Open Label
Official Title: A Randomized, Open-Label, Single?Dose, 3?Period, Crossover Evaluation of the Relative Bioavailability of Two Experimental Fixed-Dose Combination Tablet Formulations of Dolutegravir 50 mg/Abacavir 600 mg/Lamivudine 300 mg Compared to Co?Administered Dolutegravir 50 mg and EPZICOM™ (Abacavir 600 mg/Lamivudine 300 mg) Tablets in Healthy Adult Subjects
Enrollment: 18
Study Start Date: June 2011
Study Completion Date: July 2011
Primary Completion Date: July 2011 (Final data collection date for primary outcome measure)

Arms:
- Experimental: Single Arm
Subjects will be randomized in a three-way crossover design to receive a single dose of each of two different tablet formulations of dolutegravir 50 mg/abacavir 600 mg/lamivudine 300 mg or dolutegravir 50 mg plus EPZICOM (abacavir 600mg/lamivudine 300 mg). There will be a screening visit within 30 days prior to first dose and a follow-up visit 7-14 days after the last dose.