Comparison of Doravirine, Tenofovir, Lamivudine (MK-1439A) and ATRIPLA™ in Treatment-Naive Human Immunodeficiency Virus Type 1 (HIV-1)-Infected Participants (MK-1439A-021)

The purpose of this study is to compare the antiretroviral activity of doravirine, tenofovir, lamivudine (MK-1439A), a single-tablet, once-daily (q.d.) fixed-dose combination (FDC) containing doravirine (MK-1439A) 100 mg + lamivudine 300 mg + tenofovir disoproxil fumarate 300 mg, with ATRIPLA™, a single-tablet FDC containing efavirenz 600 mg + emtricitabine 200 mg + tenofovir disoproxil fumarate 300 mg, in treatment-naive participants infected with human immunodeficiency virus (HIV). The primary hypothesis is that doravirine, tenofovir, lamivudine q.d. is non-inferior to ATRIPLA™ q.d. as assessed by the proportion of participants with HIV-1 ribonucleic acid (RNA) \<50 copies/mL (by the Abbott RealTime HIV-1 Assay) at Week 48. This study has a total duration of 384 weeks, including a 96-week double-blind period and an additional 288-week open-label period.

Participants in Australia, Colombia, Guatemala, Honduras, Israel, New Zealand, Peru, Russia, South Africa, and Thailand who are deriving benefit from doravirine, tenofovir, lamivudine are also eligible to continue receiving study drug during additional open-label extensions which will last for 2 years or until drug is available locally, whichever comes first.

Eligibility Criteria:
Inclusion Criteria:

* Is HIV-1 positive as determined by a positive result on an enzyme-immunoassay, has screening plasma HIV-1 RNA (determined by the central laboratory) ≥1000 copies/mL within 45 days prior to the treatment phase of this study, and has HIV treatment indicated based on physician assessment
* Has never received antiretroviral therapy (ART)
* Is highly unlikely to either become pregnant or impregnate a partner

Exclusion Criteria:

* Has a history or current evidence of any condition, therapy, laboratory abnormality, or other circumstance that might confound results of the study
* Is a user of recreational or illicit drugs or has a recent history of alcohol/drug abuse
* Has been treated for a viral infection other than HIV-1 (e.g., hepatitis B) with an agent that is active against HIV-1
* Has participated in a study with an investigational drug/device within 30 days prior to Screening
* Has used systemic immunosuppressive therapy or immune modulators within 30 days prior to treatment in this study or is anticipated to need them during the course of the study
* Has a current (active) diagnosis of acute hepatitis due to any cause (note: participants with chronic hepatitis B and C may enter the study as long as they fulfill all entry criteria, have stable liver function tests, and have no significant impairment of hepatic synthetic function)
* Is a female who is pregnant, breastfeeding, or expecting to conceive
* Is a female and is expecting to donate eggs or is male and is expecting to donate sperm (investigators will provide appropriate guidance regarding egg and/or sperm donation after completion of the study treatment regimen)
* Has evidence of decompensated liver disease manifested by the presence of or a history of ascites, esophageal or gastric variceal bleeding, hepatic encephalopathy or other signs or symptoms of advanced liver diseases, or has liver cirrhosis and a Child-Pugh Class C score or Pugh-Turcotte (CPT) score \> 9