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 <1% per year; male
partner sterilization prior to the female subject's entry into the study, and this
male is the sole partner for that subject; any other method with published data
showing that the lowest expected failure rate is <1% per year; any contraception
method must be used consistently and in accordance with the approved product label.
All subjects participating in the study must follow safer sexual practices including
the use of effective barrier methods (e.g. male condom/spermicide) to minimize risk of
HIV transmission.

- HIV-1 infection as documented by Screening plasma HIV-1 RNA>=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 of any major
resistance-associated mutation in the Screening result or, if known, any historical
resistance test result.

- Any verified Grade 4 laboratory abnormality.

- Any acute laboratory abnormality at Screening, which, in the opinion of the
Investigator, would preclude the subject's participation in the study of an
investigational compound.

- Subject has estimated creatinine clearance <50 mL/min via Cockcroft-Gault method.

- Alanine aminotransferase (ALT) >=5 times Upper limit of normal (ULN). Subjects with
ALT >2xULN but <5xULN may participate in the study, if in the opinion of the
Investigator and GlaxoSmithKline (GSK) medical monitor the lab abnormality will not
interfere with the study procedures or compromise subject safety.

- Alanine aminotransferase (ALT) >=3xULN and bilirubin >=1.5xULN (with >35% direct
bilirubin).

- Any clinically significant finding on screening or Baseline electrocardiograph (ECG),
specifically: Heart rate <45 and >100 beats per minute (bpm) (Males) and <50 and >100
bpm (Females) (100 to 110 bpm can be rechecked within 30 minutes to verify
eligibility), QRS duration >120 milliseconds (msec), QTc interval (B or F) >450 msec;
non-sustained (>=3 consecutive beats) or sustained ventricular tachycardia; sinus
pauses >2.5 seconds; 2nd degree (Type II) or higher atrio-ventricular (AV) block;
evidence of WPW (Wolff- Parkinson-White) syndrome (ventricular pre-excitation);
pathologic Q waves defined as Q wave >40msec OR depth >0.4 mV; any significant
arrhythmia (either on ECG or by history) which, in the opinion of the Investigator and
GSK medical monitor, will interfere with the safety for the individual subject.

- Subjects who are human leukocyte antigen (HLA)-B*5701 positive and unable to use an
alternative nucleoside reverse transcriptase inhibitor (NRTI) backbone (subjects who
are HLA-B*5701 positive may be enrolled if they use an alternative NRTI backbone that
does not contain abacavir).

- Exposure to an experimental drug and/or experimental vaccine within 28 days or 5
half-lives of the test agent, or twice the duration of the biological effect of the
test agent, whichever is longer, prior to the first dose of IP.

- Treatment with any of the following agents within 28 days of Screening; radiation
therapy, cytotoxic chemotherapeutic agents, tuberculosis therapy and Immunomodulators
that alter immune responses (such as systemic corticosteroids, interleukins, or
interferons)

- Treatment with an HIV-1 immunotherapeutic vaccine within 90 days of Screening.

- Treatment with any agent, except recognized ART as allowed above, with documented
activity against HIV-1 within 28 days of the first dose of IP.