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.