Clinical studies of FTC/TAF-based regimens

Studies 109 & 1089: Study designs and baseline characteristics1-3

Study 109: Phase 3, randomized, open-label, multicenter, international, active-controlled study evaluating the efficacy of an FTC/TAF-based regimen* vs FTC/TDF-based regimens1,2

Primary endpoint1

The proportion of patients with HIV-1 RNA <50 copies/mL at Week 48

Selected secondary endpoints1,2

Changes in serum creatinine and lumbar spine and hip BMD

  • Stable virologic suppression for at least 6 months, no history of treatment failure, and no known resistance to EVG, COBI, FTC, or TAF were required for study inclusion1,2
  • All adults who received an FTC/TAF-based regimen* switched from 1 of 4 FTC/TDF-based regimens1,2
    • FTC/TDF + EFV
    • FTC/TDF + RTV-boosted ATV
    • FTC/TDF + COBI-boosted ATV

Warnings and precautions

  • Fat redistribution or accumulation has been observed in patients receiving antiretroviral therapy.

Study 109: Selected baseline characteristics1,2

Switched to
FTC/TAF-based regimen*
Remained on baseline
FTC/TDF-based regimen
Median age, years 41 40
Male (%) 89 90
Female (%) 11 10
White (%) 68 66
Black (%) 18 21
Asian (%) 6 7
Native Hawaiian (%) 1 <1
Native American (%) 1 <1
Hispanic/Latino ethnicity (%) 26 17
HIV-1 RNA <50 copies/mL (n) 943 466
Median CD4 count, cells/µL 675 662
Proteinuria by urine dipstick (any grade) (%) 9 10

Study 1089: Phase 3, randomized, double-blind, active-controlled, multicenter study evaluating the efficacy of FTC/TAF-based regimens§ vs FTC/TDF-based regimens§ while maintaining third agent3

Primary endpoint3

Proportion of patients with HIV-1 RNA <50 copies/mL at Week 48 as defined by FDA snapshot algorithm with a prespecified noninferiority margin of 10%

Selected secondary endpoints3

Percentage change from baseline in hip and lumbar spine BMD, change from baseline in serum creatinine, and change from baseline in CD4 cell count

  • Patients in the study were virologically suppressed (HIV-1 RNA <50 copies/mL) adults on a stable regimen containing FTC/TDF and 1 of the protocol-specified third agents: ATV + RTV, DRV + RTV, LPV + RTV, EFV, NVP, RPV, DTG, RAL, or MVC3

Study 1089: Selected baseline characteristics3

Switched to
FTC/TAF-based regimen
Remained on baseline
FTC/TDF-based regimen
Age, years 48 49
Male (%) 86 84
Female (%) 14 16
White (%) 73 77
Black (%) 21 20
Other (%) 6 3
Median CD4 count, cells/µL (range) 663 (505-853) 624 (477-819)
Third agent
Boosted PIs (%)|| 47 45
DRV + RTV (%) 25 25
ATV + RTV (%) 16 15
LPV + RTV (%) 5 5
Other agents (%)|| 53 55
NVP (%) 22 20
RAL (%) 20 22
DTG (%) 8 7
Others (%) 4 5

Data are median (IQR) unless stated otherwise.

Important Safety Information


  • Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogs in combination with other antiretrovirals.
  • DESCOVY is not approved for the treatment of chronic hepatitis B virus (HBV) infection and the safety and efficacy of DESCOVY have not been established in patients coinfected with HIV-1 and HBV. Severe acute exacerbations of hepatitis B have been reported in patients who are coinfected with HIV-1 and HBV and have discontinued products containing emtricitabine and/or tenofovir disoproxil fumarate (TDF), and may occur with discontinuation of DESCOVY. Hepatic function should be monitored closely with both clinical and laboratory follow-up for at least several months in patients who are coinfected with HIV-1 and HBV and discontinue DESCOVY. If appropriate, initiation of anti-hepatitis B therapy may be warranted.

Warnings and precautions

  • Fat redistribution or accumulation has been observed in patients receiving antiretroviral therapy.
  • Immune reconstitution syndrome, including the occurrence of autoimmune disorders with variable time to onset, has been reported.
  • New onset or worsening renal impairment: Cases of acute renal failure and Fanconi syndrome have been reported with the use of tenofovir prodrugs. In clinical trials of emtricitabine and tenofovir alafenamide with elvitegravir and cobicistat, there have been no cases of Fanconi syndrome or proximal renal tubulopathy (PRT). Do not initiate DESCOVY in patients with estimated creatinine clearance (CrCl) <30 mL/min. Patients with impaired renal function and/or taking nephrotoxic agents (including NSAIDs) are at increased risk of renal-related adverse reactions. Discontinue DESCOVY in patients who develop clinically significant decreases in renal function or evidence of Fanconi syndrome.
    Renal monitoring: In all patients, monitor CrCl, urine glucose, and urine protein prior to initiating and during therapy. In patients with chronic kidney disease, additionally monitor serum phosphorus.
  • Bone loss and mineralization defects: Decreases in bone mineral density (BMD) have been reported with the use of tenofovir prodrugs. Consider monitoring BMD in patients with a history of pathologic fracture or risk factors for bone loss. Mineralization defects, including osteomalacia associated with PRT, have been reported with the use of TDF-containing products.

Adverse reactions

  • Most common adverse reaction (incidence ≥10%; all grades) in clinical studies was nausea (10%).

Drug interactions

  • Prescribing information: Consult the full prescribing information for DESCOVY for more information on potentially significant drug interactions, including clinical comments.
  • Metabolism: Drugs that inhibit P-gp can increase the concentrations of components of DESCOVY. Drugs that induce P-gp can decrease the concentrations of components of DESCOVY, which may lead to loss of efficacy and development of resistance.
  • Drugs affecting renal function: Coadministration of DESCOVY with drugs that reduce renal function or compete for active tubular secretion may increase concentrations of emtricitabine and tenofovir and the risk of adverse reactions.

Dosage and administration

  • Dosage: Patients 12 years and older (≥35 kg): 1 tablet taken orally once daily with or without food.
  • Renal impairment: Not recommended in patients with CrCl <30 mL/min.
  • Testing prior to initiation: Test patients for HBV infection and assess CrCl, urine glucose and urine protein.

Pregnancy and lactation

  • Pregnancy: There are insufficient data on the use of DESCOVY during pregnancy. In animal studies, no adverse developmental effects were observed with the components of DESCOVY. An Antiretroviral Pregnancy Registry has been established.
  • Lactation: Women infected with HIV-1 should be instructed not to breastfeed, due to the potential for HIV-1 transmission.


DESCOVY® is indicated in combination with other antiretroviral (ARV) agents for the treatment of HIV-1 infection in patients 12 years and older.

Limitations of Use:
DESCOVY is not indicated for use as pre-exposure prophylaxis (PrEP) to reduce the risk of acquiring HIV-1 infection.

*Administered in combination with EVG and COBI as an STR.
Administered as an STR.
Third agents included: EVG + COBI (as an STR), EFV (as an STR), ATV + COBI, or ATV + RTV.1,2
§Patients remained on the following third agents: ATV + RTV, DRV + RTV, LPV + RTV, EFV, NVP, RPV, DTG, RAL, or MVC.3,4
||Adults on boosted PIs (ATV, DRV, and LPV, all boosted with RTV) who were randomly assigned to switch treatment received a fixed combination of 200 mg FTC with 10 mg TAF; those on other third agents received 200 mg FTC with 25 mg TAF. In the United States, only 1 dose of DESCOVY (FTC 200 mg/TAF 25 mg) is approved for use with any third agent. Adults who maintained FTC/TDF-based regimens received 200 mg FTC with 300 mg TDF for all regimens.3,5
EFV and RPV were allowed when administered as individual agents, but not as part of a single-tablet regimen.

ATV, atazanavir; COBI, cobicistat; eGFRCG, estimated glomerular filtration rate (Cockcroft-Gault); EVG, elvitegravir; FTC, emtricitabine; IQR, interquartile range; QD, once daily; RTV, ritonavir; STR, single-tablet regimen.


  1. Mills A, Arribas JR, Andrade-Villanueva J, et al; for GS-US-292-0109 team. Switching from tenofovir disoproxil fumarate to tenofovir alafenamide in antiretroviral regimens for virologically suppressed adults with HIV-1 infection: a randomised, active-controlled, multicentre, open-label, phase 3, non-inferiority study. Lancet Infect Dis. 2016;16(1):43-52.
  2. GENVOYA [package insert]. Foster City, CA: Gilead Sciences, Inc.; 2016.
  3. Gallant JE, Daar ES, Raffi F, et al. Efficacy and safety of tenofovir alafenamide versus tenofovir disoproxil fumarate given as fixed-dose combinations containing emtricitabine as backbones for treatment of HIV-1 infection in virologically suppressed adults: a randomised, double-blind, active-controlled phase 3 trial. Lancet HIV. 2016;3(4):e158-e165.
  4. Data on file. Gilead Sciences, Inc.
  5. DESCOVY [package insert]. Foster City, CA: Gilead Sciences, Inc.; 2016.

You are leaving the DESCOVY® website

By following this link, you are leaving This site is not controlled by Gilead Sciences, Inc. Gilead Sciences, Inc. is not responsible for the site's content or your use of the site.

By following this link, you are leaving