An Efficacy, Safety, and Tolerability Study Comparing Dolutegravir (DTG) Plus Lamivudine (3TC) With Dolutegravir Plus Tenofovir/Emtricitabine in Treatment naïve HIV Infected Participants (Gemini 2)

This study will compare safety, efficacy, and tolerability of a two drug regimen of dolutegravir (DTG) plus (+) lamivudine (3TC) administered once daily with DTG plus two nucleoside reverse transcriptase inhibitors (tenofovir disoproxil fumarate \[TDF\]/emtricitabine \[FTC\] fixed dose combination \[FDC\]) administered once daily in human immunodeficiency virus (HIV) 1 infected adult participants that have not previously received antiretroviral therapy. The study is designed to demonstrate the non inferior antiviral activity of DTG + 3TC regimen to that of DTG + TDF/FTC FDC and will characterise the long term antiviral activity, tolerability and safety of DTG plus 3TC through Week 148. Approximately, 700 participants will be randomised 1:1 to receive DTG + 3TC or DTG + TDF/FTC FDC. Participants will be stratified by screening HIV 1 ribonucleotide nucleic acid (RNA) levels and by screening CD4+ (cluster of differentiation 4) cell count.