Efficacy, Safety, and Tolerability of Ledipasvir/Sofosbuvir (LDV/SOF) Treatment for HIV/HCV Co-infected Participants Who Switch to Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Alafenamide (E/C/F/TAF) or Emtricitabine/Rilpivirine/Tenofovir Alafenamide (F/R/TAF) Prior to LDV/SOF HCV Treatment
Efficacy, Safety, and Tolerability of Ledipasvir/Sofosbuvir (LDV/SOF) Treatment for HIV/HCV Co-infected Participants Who Switch to Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Alafenamide (E/C/F/TAF) or Emtricitabine/Rilpivirine/Tenofovir Alafenamide (F/R/TAF) Prior to LDV/SOF HCV Treatment
This study will evaluate efficacy of ledipasvir/sofosbuvir (LDV/SOF) and safety and
 tolerability of switching to elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide
 (E/C/F/TAF) or emtricitabine/rilpivirine/tenofovir alafenamide (F/R/TAF) from the current
 antiretroviral (ARV) therapy and in virologically-suppressed, HIV-1/HCV co-infected
 participants.
Key Inclusion Criteria:

 -  Chronic genotype (GT) 1, HCV infected, male and non-pregnant/ non-lactating female
 individuals, without cirrhosis, treatment-naive or treatment-experienced with
 interferon (IFN) +/- ribavirin (RBV) +/- HCV protease inhibitor (PI).

 -  Compensated cirrhotic individuals must be HCV treatment-naive.

 -  No prior treatments with NS5A and NS5B or any HCV direct acting antivirals, except
 boceprevir, telaprevir and simeprevir, in combination with IFN and RBV

 -  Currently on an ARV regimen (2 NRTI + a third agent) without change for 6 months prior
 to screening.

 -  Documented plasma HIV-1 RNA levels < 50 copies/mL (or undetectable HIV-1 RNA level
 according to the local assay being used if the limit of detection is ≥ 50 copies/mL)
 for ≥ 6 months preceding the screening visit. After reaching HIV-1 RNA < 50 copies/mL,
 single values ("blips") of HIV-1 RNA ≥ 50 copies/mL followed by resuppression is
 allowed.

 -  For individuals with 3 or more prior ARV regimens, a regimen history should be
 provided for approval by the Sponsor.

 -  Note: Individuals that changed from TDF to TAF less than 6 months ago will be
 eligible as long as the TDF/ TAF change was the only change to the regimen.

 -  Plasma HIV-1 RNA level < 50 copies/mL at the screening visit

 -  Have no documented resistance to any of the HIV study agents at time in the past,
 including but not limited to the reverse transcriptase resistance mutations K65R,
 K70E, K101E/P, E138A/G/K/R/Q, V179L, Y181C/I/V, M184V/I, Y188L, H221Y, F227C, M230I/L,
 the combination of K103N+L100I, or 3 or more thymidine analog associated mutations
 (TAMs) that include M41L or L210W (TAMs are M41L, D67N, K70R, L210W, T215Y/F,
 K219Q/E/N/R). If a historical genotype prior to first ARV is not available or
 individual had 3 or more prior ARV regimens, individual will have proviral genotype
 analysis for archived resistance prior to Day 1.

 -  No history of HIV virologic failure

 -  No evidence of Hepatitis B infection

 -  Estimated glomerular filtration rate (eGFR) ≥ 30 mL/min as estimated by
 Cockcroft-Gault formula

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