Switch Study to Evaluate F/TAF in HIV-1 Positive Participants Who Are Virologically Suppressed on Regimens Containing FTC/TDF

Key Inclusion Criteria:

- Ability to understand and sign a written informed consent form, which must be obtained
prior to initiation of study procedures

- Currently receiving antiretroviral regimen containing FTC/TDF in combination with one
third agent for ≥ 6 consecutive months prior to screening.

- Plasma HIV-1 RNA levels < 50 copies/mL for at least 6 months preceding the screening
visit (measured at least twice using the same assay) and not experienced two
consecutive HIV-1 RNA above detectable levels after achieving a confirmed (two
consecutive) HIV-1 RNA below detectable levels on the current regimen in the past
year.

- Plasma HIV-1 RNA should be < 50 copies/mL at the screening visit.

- Normal electrocardiogram (ECG)

- Estimated glomerular filtration rate (eGFR) ≥ 50 mL/min according to the
Cockcroft-Gault formula for creatinine clearance

- Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 5 × the upper
limit of the normal range (ULN)

- Total bilirubin ≤ 1.5 mg/dL, or normal direct bilirubin (individuals with documented
Gilbert's syndrome or with Atazanavir-associated hyperbilirubinemia may have total
bilirubin up to 5 x ULN)

- Adequate hematologic function

- Serum amylase ≤ 5 × ULN

- Females of childbearing potential must agree to utilize highly effective contraception
methods or be non-heterosexually active, or practice abstinence from screening
throughout the duration of the study treatment and for 30 days following the last dose
of the study drug.

- Females who have stopped menstruating for ≥ 12 months but do not have documentation of
ovarian hormonal failure must have a serum follicle stimulating hormone (FSH) level at
screening within the post-menopausal range based on the Central Laboratory reference
range.

- 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 or be non-heterosexually active, or practice sexual
abstinence from first dose throughout the study period and for 30 days following the
last study drug dose.

Key Exclusion Criteria:

- A new AIDS-defining condition diagnosed within the 30 days prior to screening

- Hepatitis C virus (HCV) antibody positive and HCV RNA detectable

- Individuals experiencing decompensated cirrhosis (e.g., ascites, encephalopathy, etc.)

- Individuals receiving ongoing treatment with bisphosphonate to treat bone disease (eg,
osteoporosis)

- Females who are breastfeeding

- Positive serum pregnancy test

- Have an implanted defibrillator or pacemaker

- Current alcohol or substance use judged by the investigator to potentially interfere
with study compliance

- A history of malignancy within the past 5 years (prior to screening) or ongoing
malignancy other than cutaneous Kaposi's sarcoma (KS), basal cell carcinoma, or
resected, non-invasive cutaneous squamous carcinoma.

- Active, serious infections (other than HIV-1 infection) requiring parenteral
antibiotic or antifungal therapy within 30 days prior to Day 1 Visit

- Individuals receiving ongoing therapy with any of the medications not to be used with
FTC, TAF, TDF or other antiretroviral third agents.

Note: Other protocol defined Inclusion/Exclusion criteria may apply.