Switching to the single-tablet regimen of elvitegravir, cobicistat, emtricitabine, and tenofovir DF from non-nucleoside reverse transcriptase inhibitor plus coformulated emtricitabine and tenofovir DF regimens: Week 96 results of STRATEGY-NNRTI.

Background: HIV-1-infected, virologically suppressed adults wanting to simplify or change their non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimens may benefit from switching to the single-tablet regimen of elvitegravir, cobicistat, emtricitabine, and tenofovir disoproxil fumarate (E/C/F/TDF).

Objective: We examined differences in the proportion of participants with HIV-1 RNA < 50 copies/mL (Snapshot analysis), change in CD4 cell count, safety, and patient-reported outcomes in participants switching to E/C/F/TDF from an NNRTI + FTC/TDF (TVD) regimen.

Methods: STRATEGY-NNRTI was a 96-week, phase 3b, randomized, open-label, study examining the efficacy, safety, and tolerability of switching to E/C/F/TDF in virologically suppressed individuals (HIV-1 RNA < 50 copies/mL) on an NNRTI + TVD regimen.

Simplification to single-tablet regimen of elvitegravir, cobicistat, emtricitabine, tenofovir DF from multi-tablet ritonavir-boosted protease inhibitor plus coformulated emtricitabine and tenofovir DF regimens: week 96 results of STRATEGY-PI.

Background: Antiretroviral therapy (ART) simplification to a single-tablet regimen can benefit HIV-1-infected, virologically suppressed, individuals on ART composed of multiple pills.

Objective: We assessed long-term efficacy and safety of switching to co-formulated elvitegravir, cobicistat, emtricitabine, and tenofovir disoproxil fumarate (E/C/F/TDF) from multi-tablet ritonavir-boosted protease inhibitor (PI + RTV) plus F/TDF (TVD) regimens.

Methods: STRATEGY-PI was a 96-week, phase 3b, randomized (2:1), open-label, non-inferiority study examining the efficacy, safety, and tolerability of switching to E/C/F/TDF from PI + RTV + TVD regimens in virologically suppressed individuals (HIV-1 RNA <50 copies/mL).

Atazanavir Plus Cobicistat: Week 48 and Week 144 Subgroup Analyses of a Phase 3, Randomized, Double-Blind, Active-Controlled Trial.

Objectives: Cobicistat (COBI) enhances atazanavir (ATV) pharmacokinetic parameters similarly to ritonavir (RTV) in both healthy volunteers and HIV-infected adults. Primary efficacy and safety outcomes of this Phase 3, international, randomized, double-blind, double-dummy, active- controlled trial in HIV-1-infected treatment-naïve adults (GS-US-216-0114/NCT01108510) demonstrated that ATV+COBI was non-inferior to ATV+RTV, each in combination with emtricitabine/ tenofovir disoproxil fumarate (FTC/TDF), at Weeks 48 and 144, with high rates of virologic success for both regimens (85.2% and 87.

Integrase inhibitor versus protease inhibitor based regimen for HIV-1 infected women (WAVES): a randomised, controlled, double-blind, phase 3 study.

Background: Women are under-represented in HIV antiretroviral therapy (ART) studies. Guidelines for selection of ART as initial therapy in patients with HIV-1 infection do not contain sex-specific treatment. We aimed to assess the safety and efficacy of the single tablet integrase inhibitor regimen containing elvitegravir, cobicistat, emtricitabine, and tenofovir disoproxil fumarate compared with a boosted protease inhibitor regimen of ritonavir-boosted atazanavir with emtricitabine and tenofovir disoproxil fumarate.

Drug Interactions with Cobicistat- or Ritonavir-Boosted Elvitegravir.

Cobicistat and ritonavir are structurally distinct compounds that both potently inhibit cytochrome P450 (CYP) 3A, the metabolizing enzyme primarily responsible for the elimination of several antiretroviral medications, and, as such, are pharmacokinetic boosters for antiretroviral agents that require longer dosing intervals. Recently, cobicistat was approved for the treatment of HIV-1 infection in treatment-naive adults as a component of a single-tablet regimen consisting of cobicistat-boosted elvitegravir plus emtricitabine and tenofovir disoproxil fumarate. While studies have demonstrated that boosting with either cobicistat or ritonavir results in comparable plasma exposure of the target antiretroviral agent, a better understanding of drug-drug interactions between cobicistat- and ritonavir-boosted antiretrovirals and other medications will inform treatment decisions in HIV-infected patients.

Pharmacokinetics of Co-Formulated Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Disoproxil Fumarate After Switch From Efavirenz/Emtricitabine/Tenofovir Disoproxil Fumarate in Healthy Subjects.

Background: Elvitegravir (EVG), a HIV integrase inhibitor, is metabolized primarily by CYP3A, and secondarily by UGT1A1/3; Efavirenz (EFV), a HIV non-nucleoside reverse transcriptase inhibitor, is metabolized by Cytochrome P450 (CYP) 2B6 and induces CYP3A and uridine diphosphate glucuronosyltransferase (UGT) with residual effects post discontinuation because of long T1/2 (40-55 hours). This study evaluated the pharmacokinetics after switching from efavirenz/emtricitabine/tenofovir disoproxil fumarate (EFV/FTC/TDF) to elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (EVG/COBI/FTC/TDF).

Methods: Healthy subjects (n = 32 including n = 8 CYP2B6 poor metabolizers) received EVG/COBI/FTC/TDF (150/150/200/300 mg) on days 1-7, and after a washout, received EFV/FTC/TDF (600/200/300 mg) on days 15-28 and switched to EVG/COBI/FTC/TDF (150/150/200/300 mg) for 5 weeks (days 29-62).

Concordance of HIV-1 RNA Values by Amplicor and TaqMan 2.0 in Patients With Confirmed Suppression in Clinical Trials.

Background: The COBAS AMPLICOR HIV-1 MONITOR Test, version 1.5 (Amplicor) has been replaced with the COBAS AmpliPrep/COBAS TaqMan HIV-1 Test, version 2.0 (TaqMan 2.

Pulmonary hypertension in idiopathic pulmonary fibrosis with mild-to-moderate restriction.

The clinical course of pulmonary hypertension (PH) in idiopathic pulmonary fibrosis (IPF) is not known except in advanced disease.488 subjects in a placebo-controlled study of ambrisentan in IPF with mild-moderate restriction in lung volume, underwent right heart catheterisation (RHC) at baseline and 117 subjects (24%) had repeated haemodynamic measurements at 48 weeks. The subjects were categorised into a) World Health Organization (WHO) Group 3 PH (PH associated with pulmonary disease), n=68 (14%); b) WHO Group 2 PH (PH associated with left-sided cardiac disease), n=25 (5%); c) no PH but elevated pulmonary artery wedge pressure (PAWP), n=21 (4%); and d) no PH but without elevation of PAWP, n=374 (77%).

Brief Report: Cobicistat Compared With Ritonavir as a Pharmacoenhancer for Atazanavir in Combination With Emtricitabine/Tenofovir Disoproxil Fumarate: Week 144 Results.

Background: Cobicistat (COBI) is a pharmacoenhancer with no antiretroviral activity.

Methods: International, randomized double-blind active-controlled trial to evaluate the efficacy and safety of COBI vs ritonavir (RTV) as a pharmacoenhancer of atazanavir in combination with emtricitabine/tenofovir disoproxil fumarate in HIV treatment-naive patients followed through week 144.

Results: At Week 144, virologic suppression was achieved in 72% (COBI) and 74% (RTV) of patients.

Differential Reduction in Monocyte Activation and Vascular Inflammation With Integrase Inhibitor-Based Initial Antiretroviral Therapy Among HIV-Infected Individuals.

Background: Little is known about how different antiretrovirals effect inflammation and monocyte activation in human immunodeficiency virus (HIV) infection.

Methods: We examined plasma specimens obtained during a randomized, double-blinded trial in antiretroviral therapy (ART)-naive HIV-infected adults which compared the efficacy of elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (EVG/c/FTC/TDF) with that of efavirenz/emtricitabine/tenofovir disoproxil fumarate (EFV/FTC/TDF). From a random sample achieving an HIV type 1 RNA load of <50 copies/mL by week 48, changes over 24 and 48 weeks in levels of biomarkers of monocyte activation (soluble CD14 [sCD14] and soluble CD163 [sCD163]), systemic inflammation (soluble tumor necrosis factor α receptor I [sTNF-RI], interleukin 6 [IL-6], and high-sensitivity C-reactive protein [hsCRP]), and vascular inflammation (lipoprotein-associated phospholipase A2 [Lp-PLA2]) were compared.

Elvitegravir/cobicistat/emtricitabine/tenofovir DF in HIV-infected patients with mild-to-moderate renal impairment.

In HIV-1-infected treatment-naive patients with mild-to-moderate renal impairment [creatinine clearance (CrCl): 50-89 mL/min], elvitegravir/cobicistat/emtricitabine/tenofovir DF (STB, n = 33) achieved high rates of virologic success (78.8%; 95% confidence interval: 61.1% to 91.

Cobicistat-boosted protease inhibitors in HIV-infected patients with mild to moderate renal impairment.

Background: Cobicistat (COBI) is a pharmacoenhancer that optimizes systemic exposures of protease inhibitors (PIs) such as atazanavir (ATV) and darunavir (DRV).

Objective: To evaluate the efficacy and safety of switching ritonavir (RTV) to COBI in patients with creatinine clearance (CrCl) 50 to 89 mL/min who are virologically suppressed on a stable regimen containing ritonavir (RTV)-boosted ATV or DRV. Other components of the regimen remained unchanged.

Switching from ritonavir to cobicistat in HIV patients with renal impairment who are virologically suppressed on a protease inhibitor.

Introduction: Cobicistat (COBI) is a pharmacoenhancer and one of the components of ECF/TDF (elvitegravir/cobicistat/emtricitabine/tenofovir DF), which is approved in treatment-naïve HIV patients with creatinine clearance (CrCl) ≥70 mL/min. Study 118 assessed the renal safety of COBI-containing regimens in HIV patients with mild to moderate renal impairment.

Material And Methods: Phase 3, open label study in HIV-1-infected patients with CrCl 50-89 mL/min who are virologically suppressed on a stable regimen containing ritonavir (RTV)-boosted atazanavir (ATV) or darunavir (DRV).

Long-term efficacy and safety of E/C/F/TDF vs EFV/FTC/TDF and ATV+RTV+FTC/TDF in HIV-1-infected treatment-naïve subjects ≥50 years.

Introduction: In high-income countries, ≥30% of HIV-infected patients are ≥50 years (yrs) old (UNAIDS 2013). In two phases, three clinical trials (Studies 102 and 103) elvitegravir/cobicistat/emtricitabine/tenofovir DF (E/C/F/TDF; STB) had non-inferior efficacy and favourable safety vs efavirenz/emtricitabine/tenofovir DF (EFV/FTC/TDF; ATR) or ritonavir-boosted atazanavir (ATV+RTV)+FTC/TDF (TVD) in HIV-infected, treatment-naïve subjects at Week 144. The efficacy and safety of STB in subjects < or ≥50 yrs is described.

Week 144 resistance analysis of elvitegravir/cobicistat/emtricitabine/tenofovir DF versus atazanavir+ritonavir+emtricitabine/tenofovir DF in antiretroviral-naïve patients.

Objective: To describe baseline and emergent HIV-1 resistance to elvitegravir/ cobicistat/emtricitabine/tenofovir DF (EVG/COBI/FTC/TDF) and ritonavir-boosted atazanavir/emtricitabine/tenofovir DF (ATV+RTV+FTC/TDF) in HIV-1-infected, treatment-naïve subjects through 144 weeks.

Method: This was a randomized, double-blind, phase 3 study. HIV-1 protease (PR) and reverse transcriptase (RT) were sequenced at screening.

Week 144 resistance analysis of elvitegravir/cobicistat/emtricitabine/tenofovir DF versus efavirenz/emtricitabine/tenofovir DF in antiretroviral-naive patients.

Background: Here, the baseline and emergent resistance to elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (EVG/COBI/FTC/TDF) versus efavirenz (EFV)/FTC/TDF in HIV-1-infected antiretroviral-naive adults through 144 weeks from the randomized, ongoing, Phase III study GS-US-236-0102 is described.

Methods: HIV-1 protease (PR) and reverse transcriptase (RT) were sequenced at screening; patients with HIV-1 resistant to EFV, FTC or TDF were excluded. Genotypic/phenotypic analyses were performed at virological failure confirmation and baseline for PR, RT and integrase (IN) for patients with virological failure and for patients with HIV-1 RNA≥400 copies/ml at weeks 48, 96, 144 or early study drug discontinuation.

Switching from twice-daily raltegravir plus tenofovir disoproxil fumarate/emtricitabine to once-daily elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate in virologically suppressed, HIV-1-infected subjects: 48 weeks data.

Background: Pill burden, dosing frequency, and concerns about safety and tolerability are important obstacles to maintaining adequate medication adherence. Raltegravir (RAL) is indicated for twice-daily dosing and when taken with emtricitabine (FTC)/tenofovir disoproxil fumarate (TDF), it becomes a twice-daily multiple-tablet regimen. Elvitegravir (EVG)/cobicistat (COBI)/FTC/TDF, STB, is the first approved once-a-day integrase strand transfer inhibitor (INSTI) containing single-tablet regimen that combines EVG, an INSTI, and COBI, a novel pharmacoenhancer, with the preferred nucleos(t)ide backbone of FTC/TDF.

Cobicistat-boosted darunavir in HIV-1-infected adults: week 48 results of a Phase IIIb, open-label single-arm trial.

Background: Cobicistat is an alternative pharmacoenhancer to ritonavir. In healthy volunteers, darunavir exposure was comparable when darunavir 800 mg once daily was co-administered with cobicistat 150 mg once daily (as single agents or a fixed-dose combination) vs. with ritonavir 100 mg once daily.

A randomized phase 3 study comparing once-daily elvitegravir with twice-daily raltegravir in treatment-experienced subjects with HIV-1 infection: 96-week results.

: This 96-week, double-blind, active-controlled, phase 3 study, randomized subjects to elvitegravir once daily or raltegravir twice daily with a fully active, ritonavir-boosted protease inhibitor plus a third agent. The proportion of subjects randomized to elvitegravir that achieved and maintained HIV-1 RNA < 50 copies/mL through week 96 was 47.6% (167/351) compared with 45.

Cobicistat versus ritonavir as a pharmacoenhancer of atazanavir plus emtricitabine/tenofovir disoproxil fumarate in treatment-naive HIV type 1-infected patients: week 48 results.

Background:  Cobicistat (COBI) is a pharmacoenhancer with no antiretroviral activity in vitro.

Methods:  An international, randomized, double-blind, double-dummy, active-controlled trial was conducted to evaluate the efficacy and safety of COBI versus ritonavir (RTV) as a pharmacoenhancer of atazanavir (ATV) in combination with emtricitabine (FTC)/tenofovir disoproxil fumarate (TDF) in treatment-naive patients. The primary end point was a human immunodeficiency virus type 1 (HIV-1) RNA load of <50 copies/mL at week 48 by the Food and Drug Administration snapshot algorithm; the noninferiority margin was 12%.

A randomized double-blind comparison of coformulated elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate versus efavirenz/emtricitabine/tenofovir disoproxil fumarate for initial treatment of HIV-1 infection: analysis of week 96 results.

We report week 96 results from a phase 3 trial of elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (EVG/COBI/FTC/TDF, n = 348) vs efavirenz/emtricitabine/tenofovir disoproxil fumarate (EFV/FTC/TDF, n = 352). At week 48, EVG/COBI/FTC/TDF was noninferior to EFV/FTC/TDF (88% vs 84%, difference +3.6%, 95% confidence interval: -1.

A randomized, double-blind comparison of coformulated elvitegravir/cobicistat/emtricitabine/tenofovir DF vs ritonavir-boosted atazanavir plus coformulated emtricitabine and tenofovir DF for initial treatment of HIV-1 infection: analysis of week 96 results.

This ongoing, randomized, double-blind, active-controlled phase 3 international trial demonstrated the noninferior efficacy of elvitegravir/cobicistat/emtricitabine/tenofovir DF (EVG/COBI/FTC/TDF) compared with atazanavir boosted by ritonavir (ATV/RTV) plus emtricitabine/tenofovir disoproxil fumarate (FTC/TDF) at 48 weeks. Here, we report the week 96 results. Of 708 treated subjects, virological success (Food and Drug Administration snapshot) was maintained at week 96 with EVG/COBI/FTC/TDF and ATV/RTV + FTC/TDF (83% vs 82%, difference 1.