A Phase IIb Study to Evaluate a Long-Acting Intramuscular Regimen for Maintenance of Virologic Suppression (Following Induction With an Oral Regimen of GSK1265744 and Abacavir/Lamivudine) in Human Immunodeficiency Virus Type 1 (HIV-1) Infected, Antiretroviral Therapy-Naive Adult Subjects

Inclusion Criteria

• Subjects screened for this study must be HIV-1 infected and >=18 years of age.
• A female subject is eligible to enter and participate in the study if she: is of non-child-bearing potential defined as either post-menopausal (12 months of spontaneous amenorrhea and >=45 years of age) or physically incapable of becoming pregnant with documented tubal ligation, hysterectomy or bilateral oophorectomy or; is of child-bearing potential with a negative pregnancy test at both Screening and first day of the Induction Period and agrees to use one of the following methods of contraception to avoid pregnancy 2 weeks prior to administration of IP, throughout the study, and for at least 2 weeks after discontinuation of all oral study medications and for at least 52 weeks after discontinuation of GSK744 LA and TMC278 LA: Complete abstinence from intercourse (where this is the subject's preferred and usual lifestyle); double barrier method (male condom/spermicide, male condom/diaphragm, diaphragm/spermicide); approved hormonal contraception; any intrauterine device (IUD) with published data showing that the expected failure rate is =1000 c/mL.
• CD4+ cell count >=200 cells/mm^3 (or higher as local guidelines dictate).
• ART-naive defined as having no more than 10 days of prior therapy with any antiretroviral agent following a diagnosis of HIV-1 infection. Any previous exposure to an HIV integrase inhibitor or non-nucleoside reverse transcriptase inhibitor will be exclusionary.
• French subjects: In France, a subject will be eligible for inclusion in this study only if either affiliated to or a beneficiary of a social security category.

Exclusion Criteria

• Women who are breastfeeding.
• Any evidence at screening of an active Center for Disease and Prevention Control (CDC) Category C disease, except cutaneous Kaposi's sarcoma not requiring systemic therapy.
• Subjects with known moderate to severe hepatic impairment.
• Any pre-existing physical or mental condition (including substance abuse disorder) which, in the opinion of the Investigator, may interfere with the subject's ability to comply with the dosing schedule and/or protocol evaluations or which may compromise the safety of the subject.
• Subject who, in the investigator's judgment, poses a significant suicide risk. Recent history of suicidal behavior and/or suicidal ideation may be considered as evidence of serious suicide risk.
• The subject has a tattoo or other dermatological condition overlying the gluteus region which may interfere with interpretation of injection site reactions.
• History of ongoing or clinically relevant hepatitis within the previous 6 months, including chronic Hepatitis B virus (HBV) infection (HBsAg positive). Asymptomatic individuals with chronic hepatitis C virus (HCV) infection will not be excluded, however Investigators must carefully assess if therapy specific for HCV infection is required; subjects who are anticipated to require such therapy during the randomized portion of the study must be excluded.
• History of liver cirrhosis with or without hepatitis viral co-infection.
• Ongoing or clinically relevant pancreatitis.
• History of the following cardiac diseases: myocardial infarction, congestive heart failure, documented hypertrophic cardiomyopathy, sustained ventricular tachycardia.
• Personal or known family history of prolonged QT syndrome.
• Any condition which, in the opinion of the Investigator, may interfere with the absorption, distribution, metabolism or excretion of the drug or render the subject unable to receive study medication.
• History or presence of allergy or intolerance to the study drugs or their components or drugs of their class. In addition, if heparin is used during PK sampling, subjects with a history of sensitivity to heparin or heparin-induced thrombocytopenia must not be enrolled.
• Current or anticipated need for chronic anti-coagulation.
• Any evidence of primary resistance based on the presence