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

Weight and Metabolic Outcomes in Naïve HIV Patients Treated with Integrase Inhibitor-Based Antiretroviral Therapy: A Systematic Review and Meta-Analysis

BACKGROUND

The use of integrase inhibitor-based antiretroviral therapy could be associated with worse weight and metabolic outcomes in patients with HIV infection.

METHODS

PubMed, EMBASE, and Scopus were searched from inception to March 2022. We selected randomized controlled trials (RCTs) comparing integrase inhibitors with other antiretroviral classes (efavirenz-based or protease inhibitor-based therapies) in naïve HIV patients. Random effects meta-analysis was used to assess the effects of integrase inhibitors vs. controls on weight and lipid outcomes. Effects were described as mean differences (MD) and their 95% confidence intervals (CI). Certain pieces of evidence (CoE) were evaluated using the GRADE methodology.

RESULTS

Six RCTs (n = 3521) were included, with patients followed up between 48 and 96 weeks. The use of integrase inhibitors in comparison with other antiretroviral classes was associated with an increase in weight (MD 2.15 kg, 95%CI 1.40 to 2.90, I² = 0%, moderate CoE), and decreases in total cholesterol (MD -13.44 mg/dL, 95%CI -23.49 to -3.39, I² = 96%, low CoE), LDL cholesterol (MD -1.37 mg/dL, 95%CI -19.24 to -3.50, I² = 83%, low CoE), HDL cholesterol (MD -5.03 mg/dL, 95%CI -10.61 to 0.54, I² = 95%, low CoE), and triglycerides (MD -20.70 mg/dL, 95%CI -37.25 to -4.15, I² = 92%, low CoE). There was a high risk of bias in two RCTs and some concerns about bias in two RCTs.

CONCLUSIONS

In HIV patients, the use of integrase inhibitor-based therapy in comparison with protease inhibitor- or NNRTI-based therapy was associated with a small increase in weight and small decreases in lipid serum levels.

Efficacy and Durability of Dolutegravir- or Darunavir-Based Regimens in ART-Naïve AIDS- or Late-Presenting HIV-Infected Patients

BACKGROUND

Since limited data are available, we aimed to compare the efficacy and durability of dolutegravir and darunavir in advanced naïve patients.

METHODS

Retrospective multicenter study including AIDS- or late-presenting (def. CD4 ≤ 200/µL) HIV-infected patients starting dolutegravir or ritonavir/cobicistat-boosted darunavir+2NRTIs. Patients were followed from the date of first-line therapy initiation (baseline, BL) to the discontinuation of darunavir or dolutegravir, or for a maximum of 36 months of follow-up.

RESULTS

Overall 308 patients (79.2% males, median age 43 years, 40.3% AIDS-presenters, median CD4 66 cells/µL) were enrolled; 181 (58.8%) and 127 (41.2%) were treated with dolutegravir and darunavir, respectively. Incidence of treatment discontinuation (TD), virological failure (VF, defined as a single HIV-RNA > 1000 cp/mL or two consecutive HIV-RNA > 50 cp/mL after 6 months of therapy or after virological suppression had been achieved), treatment failure (the first of TD or VF), and optimal immunological recovery (defined as CD4 ≥ 500/µL + CD4 ≥ 30% + CD4/CD8 ≥ 1) were 21.9, 5.2, 25.6 and 1.4 per 100 person-years of follow-up, respectively, without significant differences between dolutegravir and darunavir (p > 0.05 for all outcomes). However, a higher estimated probability of TD for central nervous system (CNS) toxicity (at 36 months: 11.7% vs. 0%, p = 0.002) was observed for dolutegravir, whereas darunavir showed a higher probability of TD for simplification (at 36 months: 21.3% vs. 5.7%, p = 0.046).

CONCLUSIONS

Dolutegravir and darunavir showed similar efficacy in AIDS- and late-presenting patients. A higher risk of TD due to CNS toxicity was observed with dolutegravir, and a higher probability of treatment simplification with darunavir.

Comparison of Renal Function Biomarkers of Serum Creatinine and Cystatin C in HIV-Infected People on Dolutegravir-Containing Therapy

Objective(s)

HIV-1-infected Chinese patients who were treated naïve with combination dolutegravir (DTG) and tenofovir disoproxil fumarate (TDF) group, DTG without TDF group, TDF without DTG, as well as patients switched to DTG-containing therapy from other drugs were included.

Design

The dynamics of serum creatinine, cystatin C (CysC) level, eGFR_cr and eGFR_CysC at the baseline, 4 w, 12w, 24w, 36w and 48w for different group of patients were collected and evaluated.

Methods

Changes in serum creatinine, levels, eGFR_cr and eGFR_CysC were analyzed among groups and in different time-points. Intra-group correlation coefficient and Bland–Altman plot were used to compare the results of eGFR_cr and eGFR_CysC.

Results

Thirty-seven treated-naïve HIV-patients in combined DTG and TDF group (group 1), 23 in DTG without TDF patients (group 2) and 47 patients on TDF without DTG group (control group, group 3) along with 31 patients whose ART switch to DTG-containing regimens (group 4) were collected. Serum creatinine was significantly elevated in the group 1 and group 2 instead of group 3 from baseline to 48w. Mean decreased change of eGFR calculated by serum creatinine proved the same conclusion. However, there were no differences in serum cystatin C and eGFR_CysC between baseline and at 48 weeks in DTG-containing groups. Moreover, the proportion of eGFRcr decreased over 30% was significantly higher in DTG-treatment group.

Conclusion

We demonstrated the clinical benefits of CysC for assessing the glomerular filtration rate when evaluating renal function in HIV-1-infected patients treated with whether DTG combined with TDF or not.

Effects of different integrase strand transfer inhibitors on body weight in patients with HIV/AIDS: a network meta-analysis

BACKGROUND

Global antiretroviral therapy has entered a new era. Integrase strand transfer inhibitor (INSTI) has become the first choice in acquired immunodeficiency syndrome (AIDS) treatment. Because INSTI has high antiviral efficacy, rapid virus inhibition, and good tolerance. However, INSTIs may increase the risk of obesity. Each INSTI has its unique impact on weight gain in patients with human immunodeficiency virus (HIV)/AIDS. This study systematically assessed different INSTIs in causing significant weight gain in HIV/AIDS patients by integrating data from relevant literature.

METHODS

PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database (CBM), China Science and Technology Journal Database (VIP), and Wanfang databases were searched to find studies on the influence of different INSTIs in weight gain. Data on weight change were extracted, and a network meta-analysis was performed.

RESULTS

Eight studies reported weight changes in HIV/AIDS patients were included. Results of the network meta-analysis showed that the weight gain of HIV/AIDS patients treated with Dolutegravir (DTG) was significantly higher than that of Elvitegravir (EVG) [MD = 1.13, (0.18-2.07)]. The consistency test results showed no overall and local inconsistency, and no significant difference in the results of the direct and indirect comparison was detected (p > 0.05). The rank order of probability was DTG (79.2%) > Bictegravir (BIC) (77.9%) > Raltegravir (RAL) (33.2%) > EVG (9.7%), suggesting that DTG may be the INSTI drug that causes the most significant weight gain in HIV/AIDS patients.

CONCLUSION

According to the data analysis, among the existing INSTIs, DTG may be the drug that causes the most significant weight gain in HIV/AIDS patients, followed by BIC.

Do All Integrase Strand Transfer Inhibitors Have the Same Lipid Profile? Review of Randomised Controlled Trials in Naïve and Switch Scenarios in HIV-Infected Patients

In this study, we aim to explore the effects on lipids of integrase strand transfer inhibitors (INSTIs) in naïve and switch randomised controlled trials, and compare them with protease inhibitors (PIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs). We reviewed phase 3/4 randomised clinical trials in the Cochrane and PubMed databases that compare an INSTI with a boosted PI, an NNRTI, or another INSTI plus one or two nucleoside/nucleotide reverse transcriptase inhibitors (NtRTIs) in naïve patients and switching strategies in HIV-infected patients. We reported the baseline plasma concentration of total cholesterol (TC), low and high-density lipoprotein cholesterol (LDL-c, HDL-c), triglycerides (TG), and the TC/HDL-c ratio, as well as the change at weeks 48 and 96, when available. In naïve HIV-infected patients, raltegravir (RAL) and dolutegravir (DTG) have a more favourable lipid profile compared with NNRTI and boosted PI. Elvitegravir (EVG/c) has a superior lipid profile compared with efavirenz and is similar to that observed with ritonavir-boosted atazanavir except in TG, which increases less with EVG/c. In naïve patients, RAL, DTG, and bictegravir (BIC) produce a similar, slight increase in lipids. In switching trials, the regimen change based on a boosted PI or efavirenz to RAL, DTG, or BIC is associated with clinically significant decreases in lipids that are minor when the change is executed on EVG/c. No changes were observed in lipids by switching trials between INSTIs. In summary, RAL, DTG, and BIC have superior lipid profiles compared with boosted-PI, efavirenz, and EVG/c, in studies conducted in naïve participants, and they are associated with a clinically significant decrease in lipoproteins by switching studies.

Comparative efficacy, safety and durability of dolutegravir relative to common core agents in treatment-naïve patients infected with HIV-1: an update on a systematic review and network meta-analysis

Background

The objective of this study was to assess the durability of response of dolutegravir (DTG) as an antiretroviral core agent by comparing its efficacy and safety with other recommended or commonly used core agents up to 96-weeks (W96).

Methods

A previously published systematic review was updated to identify phase 3/4 randomised controlled trials (RCTs) of core agents in treatment-naïve HIV-1 patients. Efficacy [virologic suppression (VS), CD4⁺ cell change from baseline] and safety [adverse events [AEs], discontinuations, drug-related AEs [DRAEs]] were analysed at W96 using Bayesian network meta-analysis (NMA) adjusting for nucleoside/nucleotide reverse transcriptase inhibitors' (NRTIs') backbone. Subgroups of patients with VL > 100,000 copies/mL or CD4⁺ ≤ 200 cells/μL at baseline were analysed separately.

Results

The NMA included 20 studies reporting data at W96. A higher proportion of patients receiving DTG achieved VS compared to those on protease inhibitors [PI:Range:8.7%(CrI:3.1,16.0)-19.9%(10.8,30.5)], efavirenz [EFV:6.9%(1.3,10.8)] and cobicistat-boosted elvitegravir [EVG/c:8.2%(0.2,17.4)], and similar but numerically higher compared to rilpivirine [RPV:5.0%(− 2.8,12.5)], raltegravir [RAL:2.9%(− 1.6,7.7)] and bictegravir [BIC:2.7%(− 2.7,10.6)]. The probability that more patients on DTG would achieve VS at W96 compared to any other core agent was greater than 80%. A higher proportion of patients on DTG achieved VS compared to PI/rs [Range:33.1%(13.6,50.4)-45.3%(24.1,61.6)] and RAL [16.7%(3.3,31.2)] in patients with VL > 100,000 copies/mL at baseline, and similar VS was achieved in patients with CD4⁺ ≤ 200 cells/μL at baseline. DTG also achieved greater increase in CD4⁺ cells from baseline compared to EFV [32.6(10.7,54.7)], ritonavir-boosted darunavir [DRV/r:25.7(3.6,48.1)] and BIC [24.7(1.5,47.7)]. Patients receiving DTG had lower odds of discontinuing therapy by W96 compared to PI/rs, EFV, RAL and EVG/c. Patients on DTG had lower odds of experiencing an adverse event (AE) compared to patients on EFV [odds ratio:0.6(0.3,0.9)], ATV/r [0.4(0.3,0.6)] and LPV/r [0.3(0.2,0.5)]. For patients on DTG, the odds of experiencing a drug-related AE were lower than the odds for patients on EFV [0.3(0.2,0.4)], comparable to patients on RAL [1.1(0.8,1.4)] and higher than those on BIC [1.5(1.1,2.0)].

Conclusion

Un-boosted integrase inhibitors had better efficacy and similar safety compared to PI/rs at W96 in treatment-naïve patients with HIV-1, with DTG being among the most efficacious core agent, particularly in patients with baseline VL > 100,000 copies/mL or ≤ 200 CD4⁺ cells/μL, who can be difficult to treat.

Week 96 subgroup analyses of the phase 3, randomized AMBER and EMERALD trials evaluating the efficacy and safety of the once daily darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) single-tablet regimen in antiretroviral treatment (ART)-naïve and -experienced, virologically-suppressed adults living with HIV-1

BACKGROUND

Darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) 800/150/200/10 mg was investigated in AMBER (treatment-naïve adults; NCT02431247) and EMERALD (treatment-experienced, virologically-suppressed adults; NCT02269917).

OBJECTIVE

To describe a Week 96 pre-planned subgroup analysis of D/C/F/TAF arms by demographic characteristics (age ≤/>50 years, gender, black/non-black race), and baseline clinical characteristics (AMBER: viral load [VL], CD4⁺ count, WHO clinical stage, HIV-1 subtype and antiretroviral resistance; EMERALD: prior virologic failure [VF], antiretroviral experience, screening boosted protease inhibitor [PI], and boosting agent).

METHODS

Patients in D/C/F/TAF and control arms could continue on/switch to D/C/F/TAF in a single-arm, open-label extension phase after Week 48 until Week 96. Efficacy endpoints were percentage cumulative confirmed VL ≥50 copies/mL (virologic rebound; EMERALD), and VL <50 (virologic response), or ≥50 copies/mL (VF) (FDA snapshot; both trials).

RESULTS

D/C/F/TAF demonstrated high Week 96 virologic responses (AMBER: 85% [308/362]; EMERALD: 91% [692/763]) and low VF rates (AMBER: 6% [20/362]; EMERALD: 1% [9/763]). In EMERALD, D/C/F/TAF showed low virologic rebound cumulative through Week 96 (3% [24/763]). Results were consistent across subgroups, including prior antiretroviral experience in EMERALD. No darunavir, primary PI, or tenofovir resistance-associated mutations were observed post-baseline. Study-drug-related serious adverse events (AEs) and AE-related discontinuations were <1% and 2%, respectively (both D/C/F/TAF arms), and similar across subgroups. eGFR_cyst and bone mineral density improved or were stable and lipids increased through Week 96 across demographic subgroups, with small changes in total-cholesterol/HDL-cholesterol ratio.

CONCLUSIONS

D/C/F/TAF was effective with a high barrier to resistance and bone/renal safety benefits, regardless of demographic or clinical characteristics for treatment-naïve and treatment-experienced, virologically-suppressed adults.

HIV-1 Integrase Inhibitors: A Comparative Review of Efficacy and Safety

The newest class of antiretrovirals for all persons living with HIV are the integrase strand transfer inhibitors (INSTIs). Since 2007, five INSTIs have been introduced: raltegravir, elvitegravir, dolutegravir, bictegravir, and cabotegravir. The INSTIs have favorable pharmacokinetic and pharmacodynamic properties, which contribute to both their effectiveness and their ease of use. With the exception of cabotegravir, each INSTI is US Food and Drug Administration approved for treatment-naïve individuals initiating antiretroviral therapy. All of the INSTIs, except raltegravir, are approved for antiretroviral treatment simplification for virologically suppressed patients without INSTI resistance. Data also support the use of dolutegravir and raltegravir in individuals with antiretroviral resistance as part of an optimized antiretroviral regimen. INSTIs are generally well tolerated by people living with HIV compared with older classes of antiretrovirals, but emerging data suggest that some INSTIs contribute to weight gain. Due to their efficacy, safety, and ease of use, HIV treatment guidelines recommend oral INSTIs as preferred components of antiretroviral therapy for individuals initiating therapy. The newest INSTI, cabotegravir, represents an alternative to oral administration of life-long antiretroviral therapy with the availability of a long-acting injectable formulation. This review summarizes the current use of INSTIs in adults living with HIV, highlighting the similarities and differences within the class related to pharmacodynamics, pharmacokinetics, safety, dosing, and administration that contribute to their role in modern antiretroviral therapy.

Week 96 results of a phase 3 trial of darunavir/cobicistat/emtricitabine/tenofovir alafenamide in treatment-naive HIV-1 patients

BACKGROUND

Darunavir/cobicistat/emtricitabine/tenofovir alafenamide (D/C/F/TAF) 800/150/200/10 mg was investigated through 96 weeks in AMBER (NCT02431247).

METHODS

Treatment-naive, HIV-1-positive adults [screening plasma viral load ≥1000 copies/ml; CD4 cell count >50 cells/μl) were randomized (1 : 1) to D/C/F/TAF (N = 362) or D/C plus emtricitabine/tenofovir-disoproxil-fumarate (F/TDF) (N = 363) over at least 48 weeks. After week 48, patients could continue on or switch to D/C/F/TAF in an open-label extension phase until week 96.

RESULTS

At week 96, D/C/F/TAF exposure was 626 patient-years (D/C/F/TAF arm) and 109 patient-years (control arm post switch), week 96 virologic suppression (viral load <50 copies/ml; FDA-Snapshot, from baseline) was 85.1% (308/362) (D/C/F/TAF) and 83.7% (304/363) (control). Week 96 virologic failure (viral load ≥50 copies/ml; FDA-Snapshot) was 5.5% (20/362) and 4.4% (16/363), respectively. No darunavir, primary protease inhibitor or tenofovir resistance-associated mutations (RAMs) were observed post baseline. In one patient in each arm, an M184I and/or V RAM was detected. Few adverse event-related discontinuations (3% D/C/F/TAF; <1% control post switch) and no deaths occurred on D/C/F/TAF. Improved renal and bone parameters were maintained in the D/C/F/TAF arm and observed in the control arm post switch. Increases in total-cholesterol/high-density-lipoprotein--cholesterol rtio at week 96 were +0.25 versus baseline (D/C/F/TAF) and +0.24 versus switch (control).

CONCLUSION

At week 96, D/C/F/TAF resulted in high virologic response and low virologic failure rates, with no resistance development to darunavir or TAF/TDF. Bone, renal and lipid safety were consistent with known D/C/F/TAF component profiles. Control arm safety post switch was consistent with the D/C/F/TAF arm. AMBER week 96 results confirm the efficacy, high barrier to resistance and bone/renal safety benefits of D/C/F/TAF for treatment-naive patients.

Antiretroviral treatment for HIV infection: Swedish recommendations 2019

The Swedish Reference Group for Antiviral Therapy (RAV) published recommendations for the treatment of HIV infection in this journal most recently in 2017. An expert group under the guidance of RAV here provides updated recommendations. The most important updates in the present guidelines are the following: (a) The risk of HIV transmission through condomless sex from individuals with fully suppressed HIV viral load is effectively zero. (b) Pre-exposure prophylaxis (PrEP) is recommended for groups with a high risk of HIV infection. (c) Since the last update, two new substances have been registered: bictegravir and doravirine. (d) Dual treatment may be an alternative in selected patients, using lamivudine + dolutegravir or lamivudine + boosted darunavir/atazanavir. As with previous publications, recommendations are evidence-graded in accordance with the Oxford Centre for Evidence Based Medicine. This document does not cover treatment of opportunistic infections and tumours.

Assessing bias introduced in estimated glomerular filtration rate by the inhibition of creatinine tubular secretion from common antiretrovirals

BACKGROUND

Researchers must often rely on creatinine measurements to assess kidney function because direct glomerular filtration rates (GFR) and cystatin-c are rarely measured in routine clinical settings. However, HIV treatments often include dolutegravir, raltegravir, rilpivirine or cobicistat, which inhibit the proximal tubular secretion of creatinine without impairing kidney function, thus leading to measurement bias when using creatinine-based estimated GFR (eGFR). We developed eGFR correction factors to account for this potential bias.

METHODS

11,359 treatment-naive HIV-positive individuals in OPERA were included if they initiated dolutegravir, elvitegravir/cobicistat, darunavir/cobicistat, raltegravir, rilpivirine or efavirenz (control) with an eGFR >60 ml/min/1.73 m². The eGFR was corrected by adding the median decrease reported in the literature to the calculated eGFR; correction factors were not validated. Incidence rates of eGFR <60 ml/min/1.73 m² (Poisson regression) and the relationship between regimens and eGFR <60 ml/min/1.73 m² (multivariate Cox proportional hazards models) were estimated with and without eGFR correction.

RESULTS

Without eGFR correction, dolutegravir, elvitegravir/cobicistat, darunavir/cobicistat, raltegravir and rilpivirine based regimens were statistically significantly associated with a higher likelihood of eGFR <60 ml/min/1.73 m² than efavirenz. With eGFR correction, each of these regimens was associated with a statistically significantly lower likelihood of eGFR <60 ml/min/1.73 m² compared with efavirenz.

CONCLUSIONS

With increasing use of agents that inhibit tubular creatinine secretion, artificially low eGFR values could lead to erroneous conclusions in studies of HIV treatment and kidney outcomes measured with creatinine-based eGFR equations. Sensitivity analyses assessing the potential magnitude of bias arising from creatinine secretion inhibition should be performed.

Virologic Outcomes Among ART-Naïve Individuals Initiating Dolutegravir, Elvitegravir, Raltegravir or Darunavir: An Observational Study

Introduction

Dolutegravir (DTG), Elvitegravir (EVG), Raltegravir (RAL) and Darunavir (DRV) are commonly prescribed core agents for antiretroviral therapy (ART), and a need exists to compare their clinical effectiveness, as defined by virologic failure risks in real-world settings.

Methods

This observational analysis of a US clinical cohort consisted of ART-naïve people living with HIV (PLWH) in the OPERA database initiating DTG-, EVG-, RAL- or DRV-based regimens between August 2013 and July 2016, with follow-up to July 2017. PLWH were observed from first core agent initiation until core agent discontinuation, clinical activity cessation, death, or study end. Key outcomes included viral suppression (HIV RNA < 50 copies/mL) and confirmed virologic failure (two consecutive viral loads > 200 copies/mL or a viral load > 200 copies/mL followed by discontinuation). Association between core agent and time to virologic failure was assessed with multivariate Cox proportional hazards models.

Results

Overall, 4049 ART-naïve PLWH initiated EVG (47.4%), DTG (34.7%), DRV (14.6%), or RAL (3.2%). DTG and EVG initiators had generally similar baseline demographics and clinical characteristics, including race, risk of infection, baseline viral load, and baseline CD4 levels. RAL and DRV initiators were older and generally sicker than DTG initiators. During follow-up, more DTG initiators achieved virologic suppression (78.7%) compared with EVG (73.6%; p < 0.05), RAL (51.9%; p < 0.0001) and DRV (48.6%; p < 0.0001) initiators. Compared to DTG, both RAL and DRV were associated with higher rates of virologic failure, with adjusted hazard ratios (95% confidence interval) of 4.70 (3.03, 7.30) and 2.38 (1.72, 3.29), respectively. No difference was observed between EVG and DTG with an adjusted hazard ratio of 1.24 (0.94, 1.64).

Conclusion

In this large cohort representative of PLWH in care in the US, ART-naïve PLWH prescribed DTG had better virologic outcomes than RAL and DRV, but had virologic failure risks comparable to EVG, although RAL and DRV were preferentially prescribed to sicker individuals.

Funding

ViiV Healthcare.

Raltegravir 1200 mg Once Daily vs 400 mg Twice Daily, With Emtricitabine and Tenofovir Disoproxil Fumarate, for Previously Untreated HIV-1 Infection: Week 96 Results From ONCEMRK, a Randomized, Double-Blind, Noninferiority Trial

Supplemental Digital Content is Available in the Text.

Background:

Raltegravir 1200mg (2×600mg tablets) once daily (QD) demonstrated noninferior efficacy and similar safety to raltegravir 400mg twice daily (BID) at week 48 of the ONCEMRK trial. Here, we report the week 96 results from this study.

Methods:

ONCEMRK is a phase 3, multicenter, double-blind, noninferiority trial comparing raltegravir 1200mg QD with raltegravir 400mg BID in treatment-naive HIV-1–infected adults. Participants were assigned (2:1) to raltegravir 2×600mg QD or 400mg BID, both with emtricitabine and tenofovir disoproxil fumarate (FTC/TDF) for 96 weeks. Randomization was stratified by screening HIV-1 RNA and hepatitis B/C status. Efficacy was assessed as the proportion of participants with HIV-1 RNA <40 copies per milliliter (Food and Drug Administration Snapshot approach); the noninferiority margin was 10 percentage points.

Results:

Of the 797 participants who received study therapy (84.6% were men, 59.3% were white, and mean age was 35.9 years), 694 completed 96 weeks of treatment (87.6% QD; 84.4% BID), with few discontinuations because of lack of efficacy (1.1% for both groups) or adverse events (1.3% QD; 2.3% BID). At week 96, 81.5% (433/531) of QD recipients and 80.1% (213/266) of BID recipients achieved HIV-1 RNA <40 copies per milliliter (difference 1.4%, 95% confidence interval: −4.4 to 7.3). CD4⁺ T-cell counts increased >260 cells/mm³ from baseline in both groups. Resistance to raltegravir was infrequent, occurring in 0.8% of each treatment group through week 96. Adverse event rates were similar for the 2 regimens.

Conclusions:

In HIV-1–infected treatment-naive adults receiving FTC/TDF, raltegravir 1200mg QD demonstrated noninferior efficacy to raltegravir 400mg BID that was durable to week 96, with a safety profile similar to raltegravir 400mg BID.

Metabolic profiles of individuals switched to second-line antiretroviral therapy after failing standard first-line therapy for treatment of HIV-1 infection in a randomized, controlled trial

BACKGROUND

To investigate metabolic changes associated with second-line antiretroviral therapy (ART) following virological failure of first-line ART.

METHODS

SECOND-LINE was an open-label randomized controlled trial. Participants were randomized 1:1 to receive ritonavir-boosted lopinavir (LPV/r) with 2-3 nucleoside/nucleotide reverse transcriptase inhibitors (N[t]RTI group) or raltegravir (RAL group). 210 participants had a dual energy X-ray absorptiometry (DXA)-scan at baseline, week 48 and 96. We categorized participants according to second-line ART backbone: thymidine analogue (ta-NRTI) + lamivudine/emtricitabine (3[F]TC; ta-NRTI group); tenofovir (TDF)+3(F)TC (TDF group); TDF+ta-NRTI ±3(F)TC (TDF+ta-NRTI group); RAL. Changes in fasted total cholesterol (TC), low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein (HDL)-cholesterol, TC/HDL-cholesterol ratio, triglycerides and glucose from baseline to week 96 were examined. We explored the association between metabolic and DXA-assessed soft-tissue changes. Linear regression methods were used.

RESULTS

We analysed 454 participants. Participants in RAL group had greater TC increases, TC (adjusted mean difference [aMD]=0.65, 95% CI 0.33, 0.96), LDL-c (aMD=0.38, 95% CI 0.15, 0.61) and glucose (aMD=0.47, 95% CI -0.01, 0.92) compared to TDF group, and had greater increases in TC (aMD=0.65, 95% CI 0.28, 1.03), HDL-c (aMD=0.12, 95% CI 0.02, 0.23) and LDL-c (aMD=0.41, 95% CI 0.13, 0.69) compared to TDF+ta-NRTI group. TC/HDL ratio and triglycerides increased in all groups without significant differences between groups. A 1 kg increase in trunk fat mass was associated with an increase in TC.

CONCLUSIONS

We observed metabolic changes of limited clinical significance in the relatively young population enrolled in this study. However, the metabolic changes observed may have greater clinical significance in older people living with HIV or those with other concomitant cardiovascular risks.

Simplification of Antiretroviral Treatment from Darunavir/Ritonavir Monotherapy to Darunavir/Cobicistat Monotherapy: Effectiveness and Safety in Routine Clinical Practice

Our aim was to evaluate the effectiveness and safety of darunavir/cobicistat (DRV/c) monotherapy as an antiretroviral treatment simplification strategy in HIV-infected patients already on suppressive darunavir/ritonavir (DRV/r) monotherapy in routine clinical practice. We conducted a retrospective multicenter study including all adult patients switched from DRV/r monotherapy to DRV/c monotherapy while HIV-1 RNA was <50 copies/mL and who had at least one follow-up visit. The primary endpoint was the percentage of patients remaining free of treatment failure (TF), defined as discontinuation of monotherapy for any reason, including loss of follow-up. Virological failure (VF) was defined as a confirmed HIV-1 RNA ≥50 copies/mL or any change in the regimen after a single determination with HIV-1 RNA ≥50 copies/mL. Changes in renal function parameters and lipid profile were also evaluated. Factors associated with VF were analyzed using Cox regression. In this study, 173 subjects were included. The median (interquartile range) time of follow-up was 58 (50-67) weeks. Overall, 90% of patients remained free of TF during follow-up. Ten (6%) patients discontinued DRV/c monotherapy for nonvirological reasons and eight (5%) developed VF. No DRV-related mutations were identified in patients with VF. A decrease in triglyceride levels (p = .006) and estimated glomerular filtration rate (p = .005) were observed during follow-up. The presence of blips and CD4+ nadir <100 cells/mm³ were predictors of VF. In conclusion, switching to DRV/c monotherapy seems to be safe and effective in routine clinical practice in HIV-infected patients undergoing suppressive DRV/r monotherapy.

Integrase Inhibitors: After 10 Years of Experience, Is the Best Yet to Come?

The era of the integrase strand transfer inhibitors (INSTIs) for the treatment of human immunodeficiency virus (HIV) infection began with raltegravir in 2007. Since that time, several other INSTIs have been introduced including elvitegravir, dolutegravir, and, most recently, bictegravir, that have shown great utility as part of antiretroviral regimens in both treatment-naive and treatment-experienced patients. At present, antiretroviral guidelines fully endorse the INSTI class as part of all first-line treatment regimens. After 10 years of experience with INSTIs, newer agents are on the horizon such as cabotegravir and MK-2048 for potential use as either HIV pre-exposure prophylaxis or maintenance therapy. This review provides a brief overview of the INSTI class including agents currently available and those still in development, reviews available data from both completed and ongoing clinical trials, and outlines simplification strategies using INSTIs.

Bictegravir in a fixed-dose tablet with emtricitabine and tenofovir alafenamide for the treatment of HIV infection: pharmacology and clinical implications

INTRODUCTION

Current antiretroviral therapy is more effective and simpler than in previous times due to the development of new drugs with improved pharmacokinetic and pharmacodynamic profiles and the advent of single pill regimens with low toxicity that facilitate long-term adherence. The recent approval of the novel potent integrase strand-transfer inhibitor bictegravir (BIC) co-formulated with emtricitabine (FTC) and tenofovir alafenamide (TAF) in a fixed daily dose pill, B/F/TAF, adds to the list of single-tablet regimens available to treat HIV infection. Areas covered: This review provides an overview of the pharmacological and clinical information obtained from MEDLINE/PubMed publications and the latest international conferences. Expert opinion: BIC is a potent antiretroviral with an improved resistance profile over previous integrase inhibitors. Its combination with the new tenofovir prodrug TAF and FTC creates an effective regimen B/F/TAF for treatment-naïve patients and for those switching from another successful combination. B/F/TAF's favorable pharmacokinetic profile, simple dose, low pill burden, and few drug-drug interactions or treatment-related adverse events, will make it one of the preferred regimens in the future.

Impact of baseline plasma HIV-1 RNA and time to virological suppression on virological rebound according to first-line antiretroviral regimen

Objectives

We investigated the risk of virological rebound in HIV-1-infected patients achieving virological suppression on first-line combined ART (cART) according to baseline HIV-1 RNA, time to virological suppression and type of regimen.

Patients and methods

Subjects were 10 836 adults who initiated first-line cART (two nucleoside or nucleotide reverse transcriptase inhibitors + efavirenz, a ritonavir-boosted protease inhibitor or an integrase inhibitor) from 1 January 2007 to 31 December 2014. Cox proportional hazards models with multiple adjustment and propensity score matching were used to investigate the effect of baseline HIV-1 RNA and time to virological suppression on the occurrence of virological rebound.

Results

During 411 436 patient-months of follow-up, risk of virological rebound was higher in patients with baseline HIV-1 RNA ≥100 000 copies/mL versus <100 000 copies/mL, in those achieving virological suppression in > 6 months versus <6 months, and lower with efavirenz or integrase inhibitors than with ritonavir-boosted protease inhibitors. Baseline HIV-1 RNA >100 000 copies/mL was associated with virological rebound for ritonavir-boosted protease inhibitors but not for efavirenz or integrase inhibitors. Time to virological suppression >6 months was strongly associated with virological rebound for all regimens.

Conclusions

In HIV-1-infected patients starting cART, risk of virological rebound was lower with efavirenz or integrase inhibitors than with ritonavir-boosted protease inhibitors. These data, from a very large observational cohort, in addition to the more rapid initial virological suppression obtained with integrase inhibitors, reinforce the positioning of this class as the preferred one for first-line therapy.

Strength in Amalgamation: Newer Combination Agents for HIV and Implications for Practice

Antiretroviral (ART) therapy for the treatment of human immunodeficiency virus (HIV) infection has undergone significant changes over the past 30 years. Many single-tablet regimens (STRs), including newer fixed-dose combination (FDC) tablets, are available, offering patients several options for choosing a treatment regimen that works best for them. Given these changes, patients are more likely to adhere to treatment, achieve better clinical outcomes, and experience both fewer side effects and drug-drug interactions. Newer STRs include dolutegravir (DTG)/lamivudine (3TC)/abacavir (ABC) (Triumeq; Viiv Healthcare, Research Triangle Park, NC), rilpivirine (RPV)/emtricitabine (FTC)/tenofovir alafenamide (TAF) (Odefsey; Gilead, Foster City, CA), RPV/FTC/tenofovir disoproxil fumarate (TDF) (Complera; Gilead), elvitegravir (EVG)/cobicistat (COBI)/FTC/TDF (Stribild; Gilead), and EVG/COBI/FTC/TAF (Genvoya; Gilead). Recently approved FDCs, such as atazanavir (ATV)/COBI (Evotaz; Bristol-Myers Squibb, Princeton, NJ), darunavir (DRV)/COBI (Prezcobix; Janssen Products, Titusville NJ), and FTC/TAF (Descovy; Gilead), are also now available. The Department of Health and Human Services treatment guidelines for HIV recommend many of these integrase strand transfer inhibitor (INSTI) STRs as a preferred choice for initiation of treatment in both ART-naive and -experienced patients because they offer comparably faster rates of virologic suppression, reduced rates of resistance development (especially with DTG), and overall better adherence than protease inhibitors or NNRTIs. Numerous phase 3 clinical trials support these recommendations including several switch or simplification clinical trials. Notably, the novel pharmacokinetic booster COBI, with its water soluble properties, has enabled the development and coformulation of a few of these STRs and FDCs. Also, a newer tenofovir salt formulation, TAF, has an advantageous pharmacokinetic profile, contributing to better overall renal and bone tolerability compared with TDF. Further simplification regimens comprising dual ART therapies are currently being explored. This review provides an overview of the clinical efficacy and safety data for these coformulated agents, highlighting the relative impact on comparative adverse events, assessing the potential for experiencing fewer drug-drug interactions, and discussing the clinical implications regarding adherence to treatment.

Meeting the WHO 90% target: antiretroviral treatment efficacy in Poland is associated with baseline clinical patient characteristics

Introduction: Modern combined antiretroviral therapies (cART) allow to effectively suppress HIV-1 viral load, with the 90% virologic success rate, meeting the WHO target in most clinical settings. The aim of this study was to analyse antiretroviral treatment efficacy in Poland and to identify variables associated with virologic suppression.

Methods: Cross-sectional data on 5152 (56.92% of the countrywide treated at the time-point of analysis) patients on cART for more than six months with at least one HIV-RNA measurement in 2016 were collected from 14 Polish centres. Patients’ characteristics and treatment type-based outcomes were analysed for the virologic suppression thresholds of <50 and <200 HIV-RNA copies/ml. CART was categorized into two nucleos(t)ide (2NRTI) plus non-nucleoside reverse transcriptase (NNRTI) inhibitors, 2NRTI plus protease (PI) inhibitor, 2NRTI plus integrase (InI) inhibitor, nucleos(t)ide sparing PI/r+InI and three drug class regimens. For statistics Chi-square and U-Mann Whitney tests and adjusted multivariate logistic regression models were used.

Results: Virologic suppression rates of <50 copies/mL were observed in 4672 (90.68%) and <200 copies/mL in 4934 (95.77%) individuals. In univariate analyses, for the suppression threshold <50 copies/mL higher efficacy was noted for 2NRTI+NNRTI-based combinations (94.73%) compared to 2NRTI+PI (89.93%), 2NRTI+InI (90.61%), nucleos(t)ide sparing PI/r+InI (82.02%) and three drug class regimens (74.49%) (p < 0.0001), with less pronounced but significant differences for the threshold of 200 copies/mL [2NRTI+NNRTI-97.61%, 2NRTI+PI-95.27%, 2NRTI+InI-96.61%, PI/r+InI- 95.51% and 86.22% for three drug class cART) (p < 0.0001). However, in multivariate model, virologic efficacy for viral load <50 copies/mL was similar across treatment groups with significant influence by history of AIDS [OR:1.48 (95%CI:1.01–2.17) if AIDS diagnosed, p = 0.046], viral load < 5 log copies/mL at care entry [OR:1.47 (95%CI:1.08–2.01), p = 0.016], baseline lymphocyte CD4 count ≥200 cells/µL [OR:1.72 (95%CI:1.04–2.78), p = 0.034] and negative HCV serology [OR:1.97 (95%CI:1.29–2.94), p = 0.002]. For viral load threshold <200 copies/mL higher likelihood of virologic success was only associated with baseline lymphocyte CD4 count ≥200 cells/µL [OR:2.08 (95%CI:1.01–4.35), p = 0.049] and negative HCV status [OR:2.84 (95%CI:1.52–5.26), p = 0.001].

Conclusions: Proportion of virologically suppressed patients is in line with WHO treatment target confirming successful application of antiretroviral treatment strategy in Poland. Virological suppression rates depend on baseline patient characteristics, which should guide individualized antiretroviral tre0atment decisions.

Protecting bone in long-term HIV positive patients receiving antiretrovirals

INTRODUCTION

As the population of people living with HIV ages, the increase in non-AIDs morbidities is expected to increase in parallel. Maintaining bone health in those with HIV will be an important area of focus for the HIV clinician to prevent the morbidity and mortality associated with fragility fractures, the principal clinical sequela of low bone mineral density (BMD). Rates of fractures and prevalence of low bone mineral density, a risk factor for future fragility fractures, are already increased in the HIV positive population.

AREAS COVERED

This review examines the strategies to maintain bone health in those living with HIV from screening through to managing those with established low BMD or fracture, including the role for choice of or modification of antiretroviral therapy to maintain bone health. Expert commentary: The increasing complexity of managing bone health in the age of succesful antiretroviral therapy and an aging patient population as well as future perspectives which may help achieve the long term aim of minimising the impact of low BMD in those with HIV are discussed and explored.

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. Participants were randomized to switch or remain on their NNRTI-based regimen (no-switch).

RESULTS

At Week 96, 87% (251/290) of switch and 80% (115/143) of no-switch participants maintained HIV-1 RNA < 50 copies/mL (difference 6.1%; 95% CI -1.3 to 14.2%; p = 0.12) according to the FDA-defined snapshot algorithm. Both groups had similar proportions of subjects with virologic failure (2.8% switch, 1.4% no-switch). Discontinuations resulting from adverse events were infrequent (3% [9/291] switch, 2% [3/143] no-switch). Three switch participants (1%) discontinued due to renal adverse events (2 of the 3 before Week 48). Switch participants reported significant improvements in neuropsychiatric symptoms by as early as Week 4, and which were maintained through Week 96.

CONCLUSIONS

E/C/F/TDF is safe and effective and reduces NNRTI-associated neuropsychiatric symptoms for virologically suppressed HIV-positive adults switching from an NNRTI plus FTC/TDF-based 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). Participants were randomized to switch to E/C/F/TDF (switch group) or to continue their PI + RTV + TVD regimens (no-switch group). Eligibility criteria included no resistance to F/TDF or history of virologic failure, and estimated creatinine clearance ≥70 mL/min.

RESULTS

At week 96, 87% (252/290) of switch and 70% (97/139) of no-switch participants maintained HIV-1 RNA <50 copies/mL (difference: 17%, 95% CI 8.7-26.0%, p < 0.001). Superiority of the switch to E/C/F/TDF vs. no-switch was due to a smaller proportion of both virologic failures (switch, 1% [3/290]; no-switch, 6% [8/139]) and discontinuations for non-virologic reasons (switch, 11% [31/290]; no-switch, 24% [33/139]). No treatment-emergent resistance was observed in switch subjects with virologic failure. Discontinuation rates from adverse events were 3% in both groups (9/293, switch; 4/140, no-switch). Switching from PI + RTV + TVD to E/C/F/TDF was associated with significant improvements in patient-reported outcomes related to gastrointestinal symptoms (nausea and bloating).

CONCLUSION

E/C/F/TDF is a safe, effective long-term alternative to multi-tablet PI + RTV + TVD-based regimens in virologically suppressed, HIV-1-infected adults, and improves patient-reported gastrointestinal symptoms.

Bone Loss in HIV Infection

Human immunodeficiency virus (HIV) infection is an established risk factor for low bone mineral density (BMD) and subsequent fracture, and treatment with combination antiretroviral therapy (cART) leads to additional BMD loss, particularly in the first 1-2 years of therapy. The prevalence of low BMD and fragility fracture is expected to increase as the HIV-infected population ages with successful treatment with cART. Mechanisms of bone loss in the setting of HIV infection are likely multifactorial, and include viral, host, and immune effects, as well as direct and indirect effects of cART, particularly tenofovir disoproxil fumarate (TDF) and the protease inhibitors (PIs). Emerging data indicate that BMD loss following cART initiation can be mitigated by prophylaxis with either long-acting bisphosphonates or vitamin D and calcium supplementation. In addition, newer antiretrovirals, particularly the integrase strand transfer inhibitors and tenofovir alafenamide (TAF), are associated with less intense bone loss than PIs and TDF. However, further studies are needed to establish optimal bone sparing cART regimens, appropriate screening intervals, and preventive measures to address the rising prevalence of fragility bone disease in the HIV population.

HIV and Bone Complications: Understudied Populations and New Management Strategies

The higher risk of osteoporosis and fracture associated with HIV infection and certain antiretrovirals has been well established and the need for risk stratification among older adults increasingly recognized. This review focuses upon emerging data on bone complications with HIV/HCV coinfection, in children and adolescents, and with pre-exposure prophylaxis (PrEP), as well as new management strategies to minimize the negative effects of ART on bone.

Antiretroviral treatment for HIV infection: Swedish recommendations 2016

The Swedish Medical Products Agency and the Swedish Reference Group for Antiviral Therapy (RAV) have jointly published recommendations for the treatment of HIV infection on seven previous occasions (2002, 2003, 2005, 2007, 2009, 2011 and 2014). In February 2016, an expert group under the guidance of RAV once more revised the guidelines. The most important updates in the present guidelines are as follows: Tenofovir alafenamide (TAF) has recently been registered. TAF has several advantages over tenofovir disoproxilfumarate (TDF) and is recommended instead of TDF in most cases. First-line treatment for previously untreated individuals includes dolutegravir, boosted darunavir or efavirenz with either abacavir/lamivudine or tenofovir (TDF/TAF)/emtricitabine. Pre-exposure prophylaxis (PrEP) is recommended for high-risk individuals. As in the case of the previous publication, recommendations are evidence-graded in accordance with the Oxford Centre for Evidence Based Medicine ( http://www.cebm.net/oxford-centre-evidence-based-medicine-levels-evidence-march-2009/ ) ( Table 1 ). This document does not cover treatment of opportunistic infections and tumours. [Table: see text].

Elvitegravir for the treatment of HIV

INTRODUCTION

Current antiretrovirals (ARVs) have demonstrated the ability to prolong the life of an HIV infected individual via suppression of the virus and subsequent restoration of immune function. Despite significant advancement, there remains an opportunity for improvement. One ARV that attempts to fill global HIV therapeutic needs by balancing convenience, safety, and efficacy is elvitegravir (EVG). Areas covered: Using MEDLINE/PubMed, a literature search was conducted for published articles on the safety and efficacy of EVG in the treatment of HIV infection. Expert opinion: EVG offers clinicians a convenient choice for HIV-positive patients that is safe and effective for both treatment-naïve and experienced patients, as well as an option for regimen simplification in virologically suppressed patients. EVG is conveniently co-formulated in fixed dose combination tablets to be taken once daily with food. EVG does not require dose adjustment for patients with severe renal impairment or mild to moderate liver disease. Importantly, EVG requires co-administration with a pharmacokinetic enhancer (i.e., ritonavir or cobicistat) in order to achieve therapeutic levels and facilitate once daily dosing. As a consequence, clinicians must carefully review concomitant medications and navigate potential drug-drug interactions mediated through potent inhibition of cytochrome P450 3A enzymes by ritonavir and cobicistat.

Evolution of renal function in African patients initiating second-line antiretroviral treatment: findings from the ANRS 12169 2LADY trial

BACKGROUND

To investigate change in renal function in African patients initiating second-line antiretroviral therapy (ART) including ritonavir-boosted protease inhibitor (PI/r) with or without tenofovir disoproxil fumarate (TDF).

METHODS

HIV-1-positive adults, failing standard first-line ART were randomized to either TDF/emtricitabine (FTC)+LPV/r, abacavir + didanosine +LPV/r or TDF/FTC+ darunavir (DRV)/r and followed for 18 months. Patients with an estimated glomerular filtration rate (eGFR) ≥60 ml/min/1.73 m² at baseline were included in this analysis.

RESULTS

Data from 438 out of 454 randomized patients were analysed. Median age was 38 years and 72% were women. Initiation of PI/r-based second-line regimen induced a marked eGFR decline of -10.5 ml/min/1.73 m² at week 4 in all treatment groups with a greater decrease in TDF/FTC+LPV/r arm (-15.1 ml/min/1.73 m²). At month 18, mean eGFR in the non-TDF containing regimen recovered its baseline level and was significantly greater than eGFR 18-month levels in the TDF-containing regimens that experienced only partial recovery (difference: -10.7; CI -16.8, -4.6; P=0.001 in TDF/FTC+LPV/r and -6.4; CI -12.5, -0.3; P=0.04 in TDF/FTC+DRV/r). At 18 months, prevalence of stage 3 chronic kidney disease was low (<3%) and not associated with treatment. One treatment discontinuation and five TDF dosage reductions for renal toxicities were reported in TDF-containing arms.

CONCLUSIONS

Overall, these results suggest a reasonable renal tolerance of a regimen associating TDF/FTC+PI/r in African patients with eGFR>60 ml/ml/1.73 m² at baseline. They also support the recommendation of reassessing renal function 1 month after initiation of treatment including ritonavir to account for the ritonavir-related artefactual decrease of eGFR and determine the new reference baseline value.

Comparative efficacy and safety of first-line antiretroviral therapy for the treatment of HIV infection: a systematic review and network meta-analysis

BACKGROUND

New antiretroviral therapy (ART) regimens for HIV could improve clinical outcomes for patients. To inform global guidelines, we aimed to assess the comparative effectiveness of recommended ART regimens for HIV in ART-naive patients.

METHODS

For this systematic review and network meta-analysis, we searched for randomised clinical trials published up to July 5, 2015, comparing recommended antiretroviral regimens in treatment-naive adults and adolescents (aged 12 years or older) with HIV. We extracted data on trial and patient characteristics, and the following primary outcomes: viral suppression, mortality, AIDS defining illnesses, discontinuations, discontinuations due to adverse events, and serious adverse events. We synthesised data using network meta-analyses in a Bayesian framework and included older treatments, such as indinavir, to serve as connecting nodes. We defined network nodes in terms of specific antivirals rather than specific ART regimens. We categorised backbone regimens and adjusted for them through group-specific meta-regression. We used the GRADE framework to interpret the strength of inference.

FINDINGS

We identified 5865 citations through database searches and other sources, of which, 126 articles related to 71 unique trials were included in the network analysis, including 34 032 patients randomly assigned to 161 treatment groups. For viral suppression at 48 weeks, compared with efavirenz, the odds ratio (OR) for viral suppression was 1·87 (95% credible interval [CrI] 1·34-2·64) with dolutegravir and 1·40 (1·02-1·96) with raltegravir; with respect to viral suppression, low-dose efavirenz was similar to all other treatments. Both low-dose efavirenz and integrase strand transfer inhibitors tended to be protective of discontinuations due to adverse events relative to normal-dose efavirenz. The most protective effect relative to efavirenz in network meta-analyses was that of dolutegravir (OR 0·26, 95% CrI 0·14-0·47), followed by low-dose efavirenz (0·39, 0·16-0·92). Owing to insufficient data, we could make no conclusions about serious adverse events. Low event rates also limited the quality of evidence with regard to mortality and AIDS defining illnesses.

INTERPRETATION

The efficacy and safety of ART has substantially improved with the introduction of newer drug classes of antiretrovirals that are now available to patients and HIV care providers. Their improved tolerance could be part of a larger solution to improve retention, which is a challenge, particularly in low-income and middle-income country settings.

FUNDING

The World Health Organization.

Efficacy and Safety of Elvitegravir/Cobicistat/Emtricitabine/Tenofovir Disoproxil Fumarate in Asian Subjects with Human Immunodeficiency Virus 1 Infection: A Sub-Analysis of Phase 3 Clinical Trials

The efficacy and safety of a single tablet regimen (STR) of elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (E/C/F/TDF) were analyzed in Phase 3 clinical trials in antiretroviral therapy (ART)-naïve and ART-experienced Asian subjects infected with human immunodeficiency virus (HIV)-1. Studies GS-US-236-102 and GS-US-236-103 were randomized, double-blind, placebo-controlled, 144-week studies conducted in ART-naïve subjects, comparing E/C/F/TDF versus efavirenz (EFV)/F/TDF or ritonavir-boosted atazanavir (ATV+RTV) plus emtricitabine/tenofovir DF (F/TDF), respectively. Studies GS-US-236-115 and GS-US-236-121 were randomized, open-label, 96-week long conducted in ART-experienced subjects, who switched to E/C/F/TDF from ritonavir-boosted protease inhibitors (PI+RTV)+F/TDF, or non-nucleoside reverse transcriptase inhibitors (NNRTI)+F/TDF regimens. The E/C/F/TDF appeared to have sustained efficacy and safety and was well tolerated in the small number of ART-naïve and ART-experienced Asian subjects.

[Choice of initial regimen for antiretroviral-naïve HIV patients: Analysis of motivation]

OBJECTIVE

Several therapeutic combination antiretroviral therapy regimen are available for initial treatment in naïve HIV infected patients. The choice of a particular regimen remains often subjective. The aim of this study was to determine factors associated with the choice of molecules in initial ARV prescriptions.

METHODS

From 01/01 to 30/10/2014, every initial cART prescription was analyzed regarding patients and physicians characteristics. Then, prescriptions were evaluated by an independent committee of ART prescribers.

RESULTS

One hundred and thirty two consecutive initial prescriptions by 34 physicians of 11 medical centers were included: 71 M, migrants: 57 %, MSM: 21 %, CD4<200/mm³: 26 %, HIV RNA>100 000 cp/mL (33 %). cART regimen were: NRTI/PI (43 %), NRTI/NNRTI (29.5 %), NRTI/integrase inhibitor (23 %). 75 % of initial cART regimen were consistent with expert guidelines recommendations. The choice of initial cART was not influenced by the type of HIV contamination risk group, patient's geographic origin, CD4 levels. In contrast, working or not (P=0.007), pregnancy wish (P=0.07), pregnancy (P=0.001), HIV RNA levels (P=0.02) and HIV primary infection (P=0.049) influenced the initial choice. Neither physician's age, nor physician's experience influenced this choice. The prescription's non accordance to 2013 French guidelines was mainly related to integrase inhibitor utilisation (P= 0.0001).

CONCLUSION

Overall, cART initial choice is mostly consistent with guidelines. Primary HIV infection, procreation features and high viral load are the main factors influencing this choice. New regimen with better tolerability is prescribed even if it is not yet included in the guidelines.

Long-Term Efficacy, Tolerability, and Renal Safety of Atazanavir/Ritonavir-based Antiretroviral Therapy in a Cohort of Treatment-Naïve Patients with HIV-1 Infection: the REMAIN Study

BACKGROUND

Boosted protease inhibitors (PIs), including ritonavir-boosted atazanavir (ATV/r), are a recommended option for the initial treatment of HIV-1 infection based upon clinical trial data; however, long-term real-life clinical data are limited.

OBJECTIVE

We evaluated the long-term use of ATV/r as a component of antiretroviral combination therapy in the real-life setting in the REMAIN study.

METHODS

This was an observational cohort study conducted at sites across Germany, Portugal, and Spain. Retrospective historical and prospective longitudinal follow-up data were extracted every six months from medical records of HIV-infected treatment-naïve patients aged ≥ 18 years initiating a first-line ATV/r-containing regimen.

RESULTS

Eligible patients (n = 517) were followed up for a median of 3.4 years. The proportion remaining on ATV/r at 5 years was 51.5% with an estimated Kaplan-Meier median time to treatment discontinuation of 4.9 years. Principal reasons for discontinuation were adverse events (15.9%; 8.9% due to hyperbilirubinemia) and virologic failure (6.8%). The Kaplan-Meier probability of not having virologic failure (HIV-1 RNA < 50 copies/mL) was 0.79 (95% CI: 0.75, 0.83) at five years. No treatment-emergent major PI resistance occurred. ATV/r was generally well tolerated during long-term treatment with no significant changes in estimated glomerular filtration rate over five years.

CONCLUSIONS

In a real-life clinical setting over five years, treatment-naïve patients with HIV-1 infection initiating an ATV/r-based regimen showed sustained virologic suppression, an overall treatment persistence rate of 51.5%, an absence of treatment-emergent major PI resistance mutations at virologic failure, a long-term safety profile consistent with that observed in clinical trials, and no significant decline in renal function.

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.

METHODS

In this international, randomised, controlled, double-blind, phase 3 study (Women AntiretroViral Efficacy and Safety study [WAVES]), we recruited treatment-naive HIV-infected women with an estimated creatinine clearance of 70 mL/min or higher from 80 centres in 11 countries. Women were randomly assigned (1:1) to receive elvitegravir, cobicistat, emtricitabine, and tenofovir disoproxil fumarate (integrase inhibitor regimen) or ritonavir-boosted atazanavir with emtricitabine and tenofovir disoproxil fumarate (protease inhibitor based regimen); regimens were masked with matching placebos. Randomisation was done by a computer-generated allocation sequence (block size four) and was stratified by HIV-1 RNA viral load and race. Investigators, patients, study staff, and those assessing outcomes were masked to treatment group. All participants who received one dose of study drug were included in the primary efficacy and safety analyses. The main outcome was the proportion of patients with plasma HIV-1 RNA less than 50 copies per mL at week 48 as defined by US Food and Drug Administration snapshot algorithm (prespecified non-inferiority margin of 12%). This study is registered with ClinicalTrials.gov, number NCT01705574.

FINDINGS

Between Nov 28, 2012, and March 12, 2014, 575 women were enrolled. 289 were randomly assigned to receive the integrase inhibitor regimen and 286 to receive the protease inhibitor based regimen. 252 (87%) women in the integrase inhibitor group had plasma HIV-1 RNA less than 50 copies per mL at week 48 compared with 231 (81%) women in the protease inhibitor group (adjusted difference 6·5%; 95% CI 0·4-12·6). No participant had virological failure with resistance in the integrase inhibitor group compared with three participants ([1%]; all Met184Val/Ile) in the protease inhibitor group. 19 women in the protease inhibitor group discontinued because of adverse events compared with five in the integrase inhibitor group.

INTERPRETATION

WAVES shows that clinical trials of ART regimens in global and diverse populations of treatment-naive women are possible. The findings support guidelines recommending integrase inhibitor based regimens in first-line antiretroviral therapy.

FUNDING

Gilead Sciences.

Impact of elvitegravir on human adipocytes: Alterations in differentiation, gene expression and release of adipokines and cytokines

Elvitegravir is a recently developed integrase inhibitor used for antiretroviral treatment of HIV infection. Secondary effects, including disturbances in lipid metabolism and, ultimately, in adipose tissue distribution and function, are common concerns associated with antiretroviral treatments. Here, we provide the first study of the effects of elvitegravir (in comparison with efavirenz, a non-nucleoside analog inhibitor of reverse transcriptase; and raltegravir, another integrase inhibitor) on human adipocyte differentiation, gene expression and secretion of adipokines and cytokines. Elvitegravir impaired adipogenesis and adipocyte metabolism in human SGBS adipocytes in a concentration-dependent manner (delaying acquisition of adipocyte morphology and reducing the expression of adipogenesis marker genes such as PPARγ, glucose transporter GLUT4, lipoprotein lipase, and the adipokines adiponectin and leptin). Compared with efavirenz, the effects of elvitegravir were similar but tended to occur at higher concentrations than those elicited by efavirenz, or were somewhat less intense than those caused by efavirenz at similar concentration. Elvitegravir tended to cause a more moderate induction of pro-inflammatory cytokines than efavirenz. Efavirenz induced a marked concentration-dependent increase in interleukin-8 expression and release whereas elvitregravir had little effect. Raltegravir had totally neutral actions of adipogenesis, adipocyte metabolism-related gene expression and release of adipokines and cytokines. In conclusion, elvitegravir alters adipocyte differentiation and function and promotes induction of pro-inflammatory cytokines similarly to efavirenz, but several effects were less intense. Further assessment of lipid metabolism and adipose tissue function in patients administered elvitegravir-based regimes is advisable considering that totally neutral effects of elvitegravir on lipid homeostasis cannot be anticipated from the current study in vitro.

The protease inhibitors and HIV-associated bone loss

PURPOSE OF REVIEW

HIV infection is an established risk factor for osteoporosis and bone fracture. Combination antiretroviral therapy (cART) increases bone resorption leading to an additional 2-6% bone mineral density (BMD) loss within the first 1-2 years of therapy. Although tenofovir disoproxil fumarate is often blamed for antiretroviral drug-associated bone loss, evidence abounds to suggest that other agents, including the protease inhibitors (PIs), have adverse bone effects. In the current review, we examine bone loss associated with protease inhibitor use, describing the relative magnitude of bone loss reported for individual protease inhibitors. We also review the potential mechanisms associated with protease inhibitor-induced bone loss.

RECENT FINDINGS

As a class, protease inhibitors contribute to a greater degree of bone loss than other anchor drugs. HIV disease reversal and the associated immune reconstitution following cART initiation play an important role in protease inhibitor-mediated bone loss in addition to plausible direct effects of protease inhibitors on bone cells.

SUMMARY

Protease inhibitors remain an important component of cART despite their adverse effects on bone. A better understanding of factors that drive HIV/cART-induced bone loss is needed to stem the rising rate of fracture in the HIV-infected population.

Evaluating the role of atazanavir/cobicistat and darunavir/cobicistat fixed-dose combinations for the treatment of HIV-1 infection

Atazanavir/cobicistat (ATV/c) and darunavir/cobicistat (DRV/c) are newly approved once daily fixed-dose protease inhibitor combinations for the treatment of HIV-1 infection. Studies in healthy volunteers have established bioequivalence between cobicistat and ritonavir as pharmacoenhancers of both atazanavir (ATV) and darunavir (DRV). In addition, two randomized clinical trials (one Phase II and one Phase III noninferiority trial with a 144-week followup period) demonstrated that cobicistat had sustainable and comparable efficacy and safety to ritonavir as a pharmacoenhancer of ATV through 144 weeks of treatment in HIV-1-infected patients. Furthermore, one Phase III, open-label, single-arm, clinical trial reflected virologic and immunologic responses and safety outcomes consistent with prior published data for DRV/ritonavir 800/100 mg once daily, supporting the use of DRV/c 800/150 mg once daily for future treatment of treatment-naïve and -experienced HIV-1-infected patients with no DRV resistance-associated mutations. Low rates of virologic failure secondary to resistance to antiretroviral regimens were present in these clinical studies. Most notable adverse events in the ATV studies were hyperbilirubinemia and in the DRV study rash. Small increases in serum creatinine and minimally reduced estimated glomerular filtration rate Cockcroft-Gault calculation (eGFRCG) were observed in ATV/c and DRV/c clinical studies consistent with other studies evaluating elvitegravir/cobicistat/tenofovir/emtricitabine for the treatment of HIV-1 infection. These renal parameter changes occurred acutely in the first few weeks and plateaued off for the remaining study periods and are not necessarily clinically relevant. Cobicistat has numerous advantages compared to ritonavir such as fewer drug-drug interactions, being devoid of anti-HIV-1 activity, as well as it has better solubility affording coformulation with other antiretrovirals as simplified fixed-dose combinations. Overall, the recent approval of ATV/c and DRV/c offers HIV patients opportunities for improved adherence to lifelong treatment. Future studies are warranted to determine the efficacy and safety of ATV/c and DRV/c in treatment-experienced patients.

Darunavir/cobicistat once daily for the treatment of HIV

A current focus in HIV management is improving adherence by minimizing pill burden with convenient formulations, including fixed-dose combinations (FDCs). Darunavir, a HIV protease inhibitor, co-administered with low-dose ritonavir (800/100 mg once daily), is recommended in guidelines in combination with other antiretrovirals for HIV patients with no darunavir resistance-associated mutations. Cobicistat is an alternative agent to ritonavir for boosting plasma drug levels of darunavir among other antiretrovirals. Cobicistat is a more specific cytochrome P450 3A inhibitor than ritonavir without enzyme-inducing properties. This review describes the differing effects of cobicistat and ritonavir on metabolic enzymes, which explains their differing drug-drug interactions, and summarizes some of the studied drug-drug interactions for cobicistat. It also outlines the clinical development and data for a once-daily darunavir/cobicistat FDC. This FDC thus allows for a once-daily treatment regimen (including background antiretrovirals) with reduced pill burden.

Clinical use of cobicistat as a pharmacoenhancer of human immunodeficiency virus therapy

The pharmacoenhancement of plasma concentrations of protease inhibitors by coadministration of so-called boosters has been an integral part of antiretroviral therapy for human immunodeficiency virus (HIV) for 1.5 decades. Nearly all HIV protease inhibitors are combined with low-dose ritonavir or cobicistat, which are able to effectively inhibit the cytochrome-mediated metabolism of HIV protease inhibitors in the liver and thus enhance the plasma concentration and prolong the dosing interval of the antiretrovirally active combination partners. Therapies created in this way are clinically effective regimens, being convenient for patients and showing a high genetic barrier to viral resistance. In addition to ritonavir, which has been in use since 1996, cobicistat, a new pharmacoenhancer, has been approved and is widely used now. The outstanding property of cobicistat is its cytochrome P450 3A-selective inhibition of hepatic metabolism of antiretroviral drugs, in contrast with ritonavir, which not only inhibits but also induces a number of cytochrome P450 enzymes, UDP-glucuronosyltransferase, P-glycoprotein, and other cellular transporters. This article reviews the current literature, and compares the pharmacokinetics, pharmacodynamics, and safety of both pharmacoenhancers and discusses the clinical utility of cobicistat in up-to-date and future HIV therapy.

Greater change in bone turnover markers for efavirenz/emtricitabine/tenofovir disoproxil fumarate versus dolutegravir + abacavir/lamivudine in antiretroviral therapy-naive adults over 144 weeks

OBJECTIVE

Antiretroviral therapy initiation has been linked to bone mineral density and bone biomarker changes. We assessed long-term bone turnover biomarker effects over 144 weeks in patients initiating dolutegravir (DTG) + abacavir/lamivudine (ABC/3TC) versus efavirenz/emtricitabine/tenofovir disoproxil fumarate (EFV/FTC/TDF).

METHODS

Patients randomized in SINGLE received DTG (50 mg once daily) + ABC/3TC or fixed-dose combination EFV/FTC/TDF. We evaluated vitamin D serum levels and bone turnover markers (BTMs), including type 1 collagen cross-linked C-telopeptide (CTx), osteocalcin, bone-specific alkaline phosphatase (BSAP), and procollagen type 1 N-terminal propeptide (P1NP), at baseline and weeks 48, 96, and 144.

RESULTS

Among the 833 enrolled patients (68% white, 85% men), baseline median age was 35 years (range 18-85), median CD4 was 338 cells/μl, and median BMI was 24 kg/m. Fifty-three percent of patients smoked, and 6% reported baseline vitamin D use, with no meaningful differences between groups. Relative to baseline, CTx, osteocalcin, BSAP, and P1NP increased; vitamin D decreased in both groups at weeks 48, 96, and 144. Changes from baseline typically peaked at weeks 48 or 96 and for the four analytes, excluding vitamin D, with the EFV/FTC/TDF group having significantly greater changes from baseline at all time points.

CONCLUSION

DTG + ABC/3TC in antiretroviral therapy-naive patients resulted in significantly lower increases in BTMs (CTx, osteocalcin, BSAP, P1NP) compared with EFV/FTC/TDF over 144 weeks. The observed changes are consistent with results from other smaller, randomized trials. These differences in BTMs likely correlate with changes in bone mineral density over time.

Darunavir/cobicistat for the treatment of HIV-1: a new era for compact drugs with high genetic barrier to resistance

INTRODUCTION

Cobicistat-boosted darunavir is a boosted protease inhibitor in a fixed-dose combination to be approved for the treatment of human immunodeficiency virus type1 infection. It contains darunavir, a well-known protease inhibitor with a good efficacy and safety profile, and the new pharmacokinetic enhancer cobicistat. The convenience of this combination in a single pill makes this compound easier to take, thus improving adherence.

AREAS COVERED

PubMed and www.clinicaltrials.gov were searched with the term "darunavir/cobicistat" for all clinical trials conducted up to date, as well as for those ongoing and to be opened in the near future as well as for pharmacology data. A review of abstracts from major infectious diseases (particularly those dedicated to human immunodeficiency disease) and pharmacology conferences from 2010 to 2015 was also conducted.

EXPERT OPINION

improving adherence, particularly by minimizing pill burden with convenient formulations (i.e., fixed-dose combination), is one of the major objectives of modern antiretroviral treatment of patients with human immunodeficiency virus disease. Cobicistat is an alternative agent to ritonavir for boosting plasma drug levels for several antiretrovirals. Darunavir co-administered with low-dose ritonavir, in combination with other antiretrovirals, is recommended in several guidelines for treatment of patients with human immunodeficiency disease. Darunavir/cobicistat fixed-dose combination allows for a once-daily treatment regimen with a reduced pill burden. This new co formulation makes this compound easier to take, thus improving adherence.

Meta-Analysis of Studies Comparing Single and Multi-Tablet Fixed Dose Combination HIV Treatment Regimens

Availability of a single source review of once-daily fixed-dose single tablet regimen (STR) and multiple tablet fixed-dose regimen (MTR) would optimally inform healthcare providers and policy makers involved in the management of population with human immunodeficiency virus (HIV).We conducted a meta-analysis of published literature to compare patient adherence, clinical, and cost outcomes of STR to MTR.Published literature in English between 2005 and 2014 was searched using Embase, PubMed (Medline in-process), and ClinicalTrials.Gov databases. Two-level screening was undertaken by 2 independent researchers to finalize articles for evidence synthesis. Adherence, efficacy, safety, tolerability, healthcare resource use (HRU), and costs were assessed comparing STR to MTR. A random-effects meta-analysis was performed and heterogeneity examined using meta-regression.Thirty-five articles were identified for qualitative evidence synthesis, of which 9 had quantifiable data for meta-analysis (4 randomized controlled trials and 5 observational studies). Patients on STR were significantly more adherent when compared to patients on MTR of any frequency (odds ratio [OR]: 2.37 [95% CI: 1.68, 3.35], P < 0.001; 4 studies), twice-daily MTR (OR: 2.53 [95% CI: 1.13, 5.66], P = 0.02; 2 studies), and once-daily MTR (OR: 1.81 [95% CI: 1.15, 2.84], P = 0.01; 2 studies). The relative risk (RR) for viral load suppression at 48 weeks was higher (RR: 1.09 [95% CI: 1.04, 1.15], P = .0003; 3 studies) while RR of grade 3 to 4 laboratory abnormalities was lower among patients on STR (RR: 0.68 [95% CI: 0.49, 0.94], P = 0.02; 2 studies). Changes in CD4 count at 48 weeks, any severe adverse events (SAEs), grade 3 to 4 AEs, mortality, and tolerability were found comparable between STR and MTR. Several studies reported significant reduction in HRU and costs among STR group versus MTR.Study depicted comparable tolerability, safety (All-SAE and Grade 3-4 AE), and mortality and fewer Grade 3 to 4 lab abnormalities and better viral load suppression and adherence among patients on FDC-containing STR versus MTR; literature depicted favorable HRU and costs for STRs.These findings may help decision makers especially in resource-poor settings to plan for optimal HIV disease management when the choice of both STRs and MTRs are available.

HIV-1 RNA and HIV-1 DNA persistence during suppressive ART with PI-based or nevirapine-based regimens

OBJECTIVES

Whether ART regimens differ in their propensity to allow persistent HIV-1 detection remains unclear. To investigate this, we performed a cross-sectional study to characterize HIV-1 persistence in peripheral blood during suppressive therapy with NRTIs plus a PI or nevirapine.

METHODS

Residual plasma HIV-1 RNA was quantified by real-time PCR. Cell-associated proviral total HIV-1 DNA, unspliced and multiply spliced HIV-1 RNA and 2-long terminal repeat (2-LTR) circles were quantified by digital PCR.

RESULTS

Comparing PI with nevirapine recipients, residual plasma HIV-1 RNA detection rates were 47/80 (58.8%) versus 37/81 (45.7%), with median (IQR) levels of 4 (3-8) versus 4 (3-7) copies/mL (P = 0.207); detection was less likely with longer duration of suppressive ART (P = 0.020), independently of treatment. HIV-1 DNA was detected in all patients, with median levels of 2.3 (IQR 2.0-2.7) versus 2.5 (IQR 2.1-2.7) log10 copies/10(6) PBMCs, respectively; HIV-1 DNA levels were associated with pre-ART viral load (P = 0.004) and with residual HIV-1 RNA (P = 0.034), unspliced HIV-1 RNA (P = 0.001) and 2-LTR circles (P = 0.005), independently of treatment.

CONCLUSIONS

No significant differences were revealed in levels of residual plasma HIV-1 RNA, total HIV-1 DNA or intracellular markers of ongoing virus replication (unspliced and multiply spliced HIV-1 RNA and 2-LTR circles) between treatment groups.

Cobicistat: Review of a Pharmacokinetic Enhancer for HIV Infection

PURPOSE

This article reviews the clinical pharmacology, pharmacodynamic and pharmacokinetic (PK) properties, clinical efficacy and tolerability, drug interactions, and dosing and administration of cobicistat.

METHODS

Searches of MEDLINE and International Pharmaceutical Abstracts from 1964 to February 2015 were conducted using the search terms cobicistat and GS-9350. Relevant information was extracted from the identified clinical trials and review articles. Abstracts from the Conference on Retroviruses and Opportunistic Infections (2014-2015) and the Interscience Conference on Antimicrobial Agents and Chemotherapy (2013-2014) were also searched.

FINDINGS

Cobicistat is a PK enhancer lacking antiviral activity that, via selective cytochrome P-450 (CYP) 3A inhibition, inhibits the metabolism of certain antiretroviral medications and is used for prolonging their effect. Cobicistat has been studied as a booster of elvitegravir, a second-generation integrase inhibitor, and of the protease inhibitors atazanavir and darunavir. Data on its clinical efficacy and tolerability have been presented in 2 Phase II trials and in 9 Phase III trials, which reported durable efficacy in terms of achievement of sustained suppression of HIV-1 RNA levels to <50 copies/mL for at least 48 weeks. Cobicistat was generally well-tolerated in these studies. Cobicistat may increase serum creatinine levels via the inhibition of proximal renal tubular cell transporters and thus reduce estimated glomerular filtration rate, although it does not appear to affect actual glomerular filtration rate. Given the potent CYP3A inhibition by cobicistat, its coadministration with drugs metabolized by CYP3A may result in increased plasma concentrations of such agents. Moreover, as cobicistat is metabolized predominantly by CYP3A, plasma concentrations may increase or decrease on coadministration with CYP3A inhibitors or inducers, respectively.

IMPLICATIONS

With potent durability through 48 weeks, a tolerability profile comparable to other first- and second-line antiretroviral therapies, and a convenient dosing schedule with low daily pill burden in fixed-dose combination tablets, cobicistat is a potential addition to the management of HIV infection as a PK enhancer. However, the effects of cobicistat on serum creatinine and its considerable drug-interaction potential may warrant additional monitoring.

Review of integrase strand transfer inhibitors for the treatment of human immunodeficiency virus infection

Integrase strand transfer inhibitors (INSTIs) are oral antiretroviral agents used against HIV infection. There are three agents available, including raltegravir, elvitegravir and dolutegravir, some of which are available as combination medications with other antiretroviral drugs. The efficacy and safety of INSTIs in treatment-naïve and experienced HIV-infected patients have been established by multiple studies. Based on the current practice guidelines, INSTI-based regimens are considered as one of the first-line therapies for treatment-naïve HIV-infected patients. There are new INSTIs in development to improve the resistance profile and to decrease the frequency of drug administration.

Effects of raltegravir combined with tenofovir/emtricitabine on body shape, bone density, and lipids in African-Americans initiating HIV therapy

BACKGROUND

Raltegravir (RAL) plus tenofovir/emtricitabine (TDF/FTC) is a recommended initial antiretroviral regimen. A substantial proportion of persons diagnosed with HIV infection and starting antiretrovirals in the U.S. are African-American (AA); however, the effects of this regimen on metabolic parameters have largely been studied in white patients.

METHODS

Single-arm, open-label study of untreated AA HIV-infected patients administered RAL with TDF/FTC for 104 weeks. Changes in fasting lipids, insulin resistance, visceral adipose tissue (VAT), abdominal subcutaneous adipose tissue (SAT), limb and trunk fat, and bone mineral density (BMD) were assessed at weeks 56 and 104.

RESULTS

Thirty (85% men) participants were included. Median entry characteristics included age of 38 years, CD4 323 cells/mm3, HIV RNA level 29,245 copies/ml, and body mass index 28.1 kg/m2. At 56 and 104 weeks, significant increases in VAT, trunk fat, limb fat, and overall fat were observed. Bone mineral density decreased by 1.5% by week 104.There were no significant changes in non-HDL-cholesterol, fasting triglycerides, or insulin resistance. A median CD4 cell count increase of 318 cells/mm3 (IQR 179, 403; full range 40, 749) (P<0.001) was observed. Assuming missing=failure, 78 and 70% had HIV RNA levels<40 copies/ml at weeks 56 and 104, respectively. There were no treatment-related discontinuations and no new antiretroviral resistance mutations were detected.

CONCLUSIONS

In this cohort of AAs, initiation of RAL with TDF/FTC was associated with significant general increases in fat. Significant changes in lipids or insulin resistance were not observed and there was a small decline in BMD. Therapy was well tolerated and effective. These results are consistent with findings of studies of initial antiretroviral therapy in racially diverse cohorts and inform treatment selection for AA patients starting therapy for HIV infection.