An Open-label, Randomized, Two-way Crossover, Single Dose, Pivotal Bioequivalence Study of a Fixed-dose Combination of Dolutegravir and Rilpivirine in Healthy Volunteers

The purpose of the study is to evaluate the bioequivalence between Fixed-dose Combination
(FDC) tablet formulation of Dolutegravir (DTG) 50 milligrams (mg) and Rilpivirine (RPV) 25 mg
versus co-administration of the separate tablet formulations of DTG 50 mg plus RPV 25 mg, in
the fed state. This pivotal bioequivalence study, is to serve as a pharmacokinetic (PK)
bridge to the ongoing Phase 3 trials with the separate agents. This study will be conducted
under fed conditions to appropriately mimic the conditions in the Phase 3 trials. This is a
single-center, randomized, open-label, 2-period, single-dose, crossover study. A minimum of
86 healthy adult subjects will be randomized such that a minimum of approximately 82
evaluable subjects complete the study. The total duration of participation of a subject in
this study will be approximately 8 weeks which includes a screening visit within 30 days
prior to the first dose of study drug, two treatment periods each with a single dose of study
drug and a follow-up visit within 12-17 days after the last dose of study drug. There will be
a washout of at least 21 days between each dose of study drug.

A blinded (for treatment) review of DTG and RPV plasma concentration data for approximately
the first 40 subjects will be conducted. If the within-subject coefficients of variation
(CVw%) for either DTG or RPV maximal drug concentration (Cmax) values are >=31%; a sample
size re-estimation will be employed and additional subjects (beyond the 86 planned) will be
randomized for treatment in the study. Following the re-estimation, it is possible that up to
approximately 154 healthy adult subjects (68 new subjects in addition to the planned 86
subjects above) will be randomized such that a maximum of approximately 146 evaluable
subjects could complete the study.