Effects of Switching From ATRIPLA™ (Efavirenz, Tenofovir, Emtricitabine) to MK-1439A (Doravirine, Tenofovir, Lamivudine) in Virologically-Suppressed Participants (MK-1439A-028)

This study aims to evaluate a switch from fixed dose combination (FDC) treatment with ATRIPLA\^TM for 12 weeks prior to screening to FDC treatment with Doravirine, Tenofovir, Lamivudine (MK-1439A) in virologically-suppressed, human immunodeficiency virus type 1 (HIV-1)-infected participants. The primary hypothesis is that switching from ATRIPLA\^TM to Doravirine, Tenofovir, Lamivudine results in a lower proportion of participants with at least one CNS toxicity of at least Grade 2 intensity at Week 12 than continuation of ATRIPLA\^TM treatment.


Eligibility Criteria:
Inclusion Criteria:

* is taking ATRIPLA™, generic versions of ATRIPLA™, or the components of ATRIPLA™ (EFV,TDF plus emtricitabine),
* has documentation of HIV-1 ribonucleic acid (RNA) \< 50 copies/mL during the 12 weeks prior to screening while on ATRIPLA™.
* has plasma HIV-1 RNA levels below the limits of quantification (BLoQ) at the screening visit.
* if genotyped prior to starting initial antiretroviral regimen, must have no known resistance to any of the study agents
* has at least one EFV-associated CNS toxicities of Grade 2 or worse intensity both at the time of screening and at Study Day 1
* is highly unlikely to become pregnant or to impregnate a partner
* To be eligible for study extension 1, participants from Immediate Switch Group (ISG) must have completed Study Week 24, and benefited from study participation; participants from Deferred Switch Group (DSG) must have completed Study Week 36, and benefited from study participation as determined by the investigator
* To be eligible for study extension 2, participants from ISG must have completed Study Week 120, and benefited from study participation; participants from DSG must have completed Study Week 132, and benefited from study participation as determined by the investigator

Exclusion Criteria:

* is a user of recreational or illicit drugs or has had a recent history of drug or alcohol abuse or dependence.
* has ongoing Grade 4 CNS toxicity during screening period that requires a prompt change in ART
* has been treated for a viral infection other than HIV-1, such as hepatitis B, with an agent that is active against HIV-1 including, but not limited to, adefovir, emtricitabine, entecavir, lamivudine or tenofovir.
* has documented or known resistance to study drugs including doravirine, lamivudine, and/or tenofovir
* has participated in, or anticipates participating in a study with an investigational compound/device within 30 days prior to signing informed consent
* has used systemic immunosuppressive therapy or immune modulators or anticipates using them within 30 days prior to this study
* requires or anticipates requiring any of the prohibited medications
* has significant hypersensitivity or other contraindication to any of the components of the study drugs
* has a current (active) diagnosis of acute hepatitis due to any cause.
* 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.
* is pregnant, breastfeeding, or expecting to conceive.
* female is expecting to donate eggs (at any time during the study) or male is expecting to donate sperm (at any time during the study).