Open-Label Pilot Study to Evaluate Switching From a Regimen Consisting of Raltegravir Plus Emtricitabine/Tenofovir DF Fixed-Dose Combination to the Elvitegravir/Cobicistat/Emtricitabine/Tenofovir DF Single-Tablet Regimen in Virologically Suppressed, HIV-1 Infected Patients

Inclusion Criteria: * Ability to understand and sign a written informed consent form * Virologically stable on the current first antiretroviral regimen consisting only of raltegravir twice daily plus FTC/TDF continuously for ≥ 6 months preceding the screening visit and * have documented undetectable plasma HIV-1 RNA levels ≥ 6 months preceding the screening visit (measured at least twice using the same assay) and * have never experienced two consecutive HIV-1 RNA above detectable levels after first achieving a confirmed HIV-1 RNA level below detectable levels on the first regimen * HIV-1 RNA \< 50 copies/mL at the screening visit * Have a genotype prior to starting initial antiretroviral therapy and have no known resistance to any of the study agents at any time * Normal ECG * Hepatic transaminases ≤ 5 x upper limit of normal (ULN) * Total bilirubin ≤ 1.5 mg/dL * Adequate hematologic function * Serum amylase ≤ 5 x ULN * Estimated glomerular filtration rate ≥ 70 mL/min * Females of childbearing potential must agree to utilize highly effective contraception methods or be non-heterosexually active, practice sexual abstinence or have a vasectomized partner from screening throughout the duration of the study period and for 30 days following the last dose of study drug * Females who utilize hormonal contraceptive as one of their birth control methods must have used the same method for at least three months prior to study dosing * Males must agree to utilize a highly effective method of contraception during heterosexual intercourse from the screening visit, throughout the duration of the study and for 30 days following discontinuation of investigational medicinal product or must be non heterosexually active, practice sexual abstinence, or be vasectomized Exclusion Criteria: * New AIDS defining condition diagnosed within the 21 days prior to screening * Females who are breastfeeding * Positive serum pregnancy test (female of childbearing potential) * Individuals with acute or chronic hepatitis B or hepatitis C co-infection * Individuals experiencing decompensated cirrhosis * Have an implanted defibrillator or pacemaker * Current alcohol or substance abuse that would interfere with compliance * A history of malignancy within the past 5 years or ongoing malignancy other than cutaneous Kaposi's sarcoma, basal cell carcinoma, or resected, non-invasive cutaneous squamous carcinoma * Active, serious infections requiring parenteral antibiotic or antifungal therapy within 21 days prior to the baseline visit * Receiving any investigational drugs * Participation in any other clinical trial without prior approval from the sponsor * Have been treated with immunosuppressant therapies or chemotherapeutic agents within 3 months of study screening, or expected to receive these agents or systemic steroids during the study * Any other clinical condition or prior therapy that would make the individual unsuitable for the study or unable to comply with the dosing requirements * Receiving ongoing therapy or anticipated to need to initiate drugs or herbal/natural supplements during the study that are contraindicated or not recommended for use, including drugs not to be used with Stribild; or individuals with known allergies to the excipients of the Stribild single tablet regimen