Better adherence with once-daily antiretroviral regimens: a meta-analysis

Self-reported adherence supports patient preference for the single tablet regimen (STR) in the current cART era

OBJECTIVE

To analyze self-reported adherence to antiretroviral regimens containing ritonavir-boosted protease inhibitors, nonnucleoside reverse transcriptase inhibitors (NNRTI), raltegravir, and maraviroc.

METHODS

Overall, 372 consecutive subjects attending a reference center for HIV treatment in Florence, Italy, were enrolled in the study, from December 2010 to January 2012 (mean age 48 years). A self-report questionnaire was filled in. Patients were defined as "nonadherent" if reporting one of the following criteria: <90% of pills taken in the last month, ≥1 missed dose in the last week, spontaneous treatment interruptions reported, or refill problems in the last 3 months. Gender, age, CD4, HIV-RNA, years of therapy, and type of antiretroviral regimen were analyzed with respect to adherence.

RESULTS

At the time of the questionnaire, 89.8% of patients had <50 copies/mL HIV-RNA and 14.2% were on their first combined antiretroviral therapy. 57% of patients were prescribed a regimen containing ritonavir boosted protease inhibitors (boosted PI), 41.7% NNRTI, 17.2% raltegravir, and 4.8% maraviroc; 49.5% of the subjects were on bis-in-die regimens, while 50.5% were on OD regimens, with 23.1% of these on the single tablet regimen (STR): tenofovir/emtricitabine/efavirenz. The nonadherence proportion was lower in NNRTI than in boosted-PI treatments (19.4% vs 30.2%), and even lower in STR patients (17.4%). In multivariable logistic regression, patients with the NNRTI regimen (OR: 0.56, 95% CI: 0.34-0.94) and the STR (OR: 0.45, 95% CI: 0.22-0.92) reported lower nonadherence. Efavirenz regimens were also associated with lower nonadherence (OR: 0.42, 95% CI: 0.21-0.83), while atazanavir/ritonavir regimens were associated with higher nonadherence. No other relation to specific antiretroviral drugs was found. A higher CD4 count, lower HIV-RNA, and older age were also found to be associated with lower nonadherence, while a longer time on combined antiretroviral therapy was related to higher nonadherence.

CONCLUSION

STR maintains an advantage in improving adherence with respect to other combined antiretroviral therapies, even though new antiretroviral drugs and drug classes have become available in recent years.

Beliefs about antiretroviral therapy, treatment adherence and quality of life in a 48-week randomised study of continuation of zidovudine/lamivudine or switch to tenofovir DF/emtricitabine, each with efavirenz

Adherence may be facilitated by reducing perceptual and practical barriers to antiretroviral therapy (ART). Practical barriers include the complexity of daily dosing, while perceptual barriers include perceptions of the need for treatment and concerns about adverse effects. The study aim was to assess the effect of switching zidovudine plus lamivudine twice-daily (Combivir, CBV) to once-daily tenofovir DF plus emtricitabine (Truvada, TVD), each plus efavirenz (EFZ), on adherence, beliefs about ART and quality of life (QoL). Subjects stable on CBV + EFV were randomised 1:1 to continue this regimen or switch to TVD + EFV. Adherence was measured using the Medication Adherence Self-Report Inventory at 4, 12, 24 and 48 weeks. Beliefs about ART (perceptions of necessity and concerns about adverse effects), treatment intrusiveness and QoL were measured by questionnaire at baseline 4, 12, 24 and 48 weeks. Viral load was assessed at each visit. Two hundred and thirty-four subjects initiated treatment. At week 48, the proportion of subjects reporting high adherence (≥95% taken as prescribed) was significantly greater in the TVD arm (p=0.049). Low adherence (reporting taking <95% as prescribed, discontinuing the study or having missing data) was associated with doubts about necessity (p=0.020), stronger concerns about adverse effects (p=0.010), greater treatment intrusiveness (p=0.010) and poorer mental health related QoL (p=0.008). At week 48, both concerns about ART (p=0.038) and treatment intrusiveness (p=0.004) were lower among those who switched to TVD. Furthermore, there was a decline in both concerns about ART (p=0.007) and treatment intrusiveness (p=0.057) over the 48 weeks among those who switched to TVD. There were no significant differences in necessity beliefs, QoL or viral load between randomised groups. Switching from CBV to TVD may improve patient reported outcomes including slightly better adherence, a greater reduction in concerns about adverse effects and less treatment intrusiveness.

Clinical implications of fixed-dose coformulations of antiretrovirals on the outcome of HIV-1 therapy

The substitution by generic equivalents of some of the drugs included in fixed-dose antiretroviral coformulations (FDACs) poses the potential risk of disrupting these combinations and administering the components separately in order to incorporate the new generic drug, which offers a more competitive sales price. This may represent a step backwards in the advances achieved in simplicity and adherence to therapy, posing an increased risk of selective noncompliance of some of the separately administered drug substances. Available antiretroviral drugs must be administered for life in the affected individuals - both children and adults. The FDACs represent a significant advance in the simplification of antiretroviral therapy, facilitating adherence to complex and chronic treatments, and contributing to a quantifiable improvement in patient quality of life. These drug coformulations reduce the risk of treatment error, are associated with a lower risk of hospitalization, and can lessen the possibility of covert monotherapy in situations of selective noncompliance. Thus, FDACs can reduce the risk of selection of HIV-1 resistances, which not only adversely affect the treatment options of the individual patient but also constitute a public health problem, and further increase the cost and complexity of therapy. With the exception of those cases requiring dose adjustments, the preferential use of FDACs should be recommended for the treatment of HIV-1 infection in those situations when the agents included in the coformulation are drugs of choice.

The charms and challenges of antiretroviral therapy in Uganda: the DART experience

Antiretroviral therapy (ART) improves the quality of life of people living with HIV/AIDS. However, adherence remains a challenge. A total of eight focus group discussions (FGD) were conducted with participants from a randomised controlled trial that monitored strategies for managing ART in African adults: Development of Antiretroviral Therapy. All FGD participants had received ART for at least one year. Perceived benefits of ART were key motivators for adherence. These benefits included improved physical health, restored self-esteem, acceptance in the community and hope for a longer and healthier life and reduced fear of HIV/AIDS-related death. Barriers to adherence included a high pill burden, ART side effects and socio-economic constraints, including lack of food and safe water for taking the pills. Visible ART side effects and involvement in an exclusively HIV/AIDS clinic could expose their HIV status, thus exacerbating stigma. Gender and socio-economic differences were found in the variety of strategies employed to ensure adherence. ART was perceived as improving the overall quality of life of recipients; however, it is crucial for ART programmes to be gender and socio-economic cognizant in order to enhance adherence to a lifelong therapy.

Week 48 analysis of once-daily vs. twice-daily darunavir/ritonavir in treatment-experienced HIV-1-infected patients

OBJECTIVE

ODIN (Once-daily Darunavir In treatment-experieNced patients) was a phase III, 48-week, open-label study comparing once-daily vs. twice-daily darunavir/ritonavir (DRV/r) in treatment-experienced patients with no DRV resistance-associated mutations (RAMs) at screening.

METHODS

Patients with no DRV RAMs and receiving stable HAART for at least 12 weeks were stratified by HIV-1 RNA (≤ or > 50 000 copies/ml) and randomized to once-daily DRV/r 800/100 mg or twice-daily DRV/r 600/100 mg and an optimized background regimen (≥2 nucleoside reverse transcriptase inhibitors). Primary objective was to demonstrate noninferiority of once-daily vs. twice-daily DRV/r in confirmed virologic response (HIV-1 RNA < 50 copies/ml) at week 48.

RESULTS

Five hundred and ninety patients received once-daily (n = 294) or twice-daily (n = 296) DRV/r. Mean baseline HIV-1 RNA was 4.16 log10 copies/ml; median CD4 cell count was 228 cells/μl; and 53.9% had previously used at least one protease inhibitor. At week 48, 72.1% of once-daily and 70.9% of twice-daily patients achieved HIV-1 RNA less than 50 copies/ml (intent-to-treat/time-to-loss of virologic response). The difference in response between once-daily and twice-daily arms was 1.2% (95% confidence interval -6.1 to 8.5%; P < 0.001), establishing noninferiority of once-daily DRV/r versus twice-daily DRV/r. Median CD4 cell count increase was 100 (once-daily) and 94 cells/μl (twice-daily). Virologic failure rate was low and similar for both arms; only one patient (once-daily arm) developed primary protease inhibitor mutations. Once-daily DRV/r had a lower incidence of grade 2-4 triglyceride increases (5.2 vs. 11.0%, P < 0.05).

CONCLUSION

Once-daily DRV/r 800/100 mg was noninferior in virologic response to twice-daily DRV/r 600/100 mg at 48 weeks in treatment-experienced patients with no DRV RAMs, and with a more favorable lipid profile. These findings support use of once-daily DRV/r in this population.

Nevirapine once daily: pharmacology, metabolic profile and efficacy data of the new extended-release formulation

INTRODUCTION

Nevirapine (NVP), a non-nucleoside reverse transcriptase inhibitor, has been an important component of HIV infection treatment for many years. Currently, twice-a-day dosing is required for the successful application of NVP immediate release (IR), but there is potential for a more convenient once-a-day antiretroviral combination.

AREAS COVERED

The purpose of this article is to review the recent data on once-daily NVP extended release (XR) looking at all the important pharmacologic, pharmacokinetic and clinical data on NVP IR/XR through a systematic MEDLINE database search as well as a review of abstracts presented at international HIV meetings on NVP XR studies up to December 2010. The article provides the reader with an overview of all the pharmacodynamic and pharmacokinetic aspects of NVP IR/XR, as well as its preclinical and clinical efficacy and its safety.

EXPERT OPINION

NVP XR is as effective as NVP IR among HIV-infected patients with a similar safety profile. NVP XR requires careful monitoring during initiation, but its favorable lipid profile may be of clinical benefit in reducing the risk for coronary artery disease in HIV-infected patients who are receiving long-term antiretroviral therapy. Further research is needed to predict short-term toxicity.

Levels of adherence required for virologic suppression among newer antiretroviral medications

OBJECTIVE

To determine the adherence levels needed for HIV virologic suppression with newer antiretroviral (ARV) medications, including darunavir, etravirine, and raltegravir.

DATA SOURCES

Literature searches of PubMed, MEDLINE (1950-October 2010), and Google Scholar were performed using the following key words in multiple combinations: antiretroviral, HIV, AIDS, adherence, darunavir, raltegravir, and etravirine. A review of the bibliographies of retrieved articles was performed to identify additional references.

STUDY SELECTION AND DATA EXTRACTION

All articles in English were identified from the data sources and evaluated. Studies that did not state names of medications or drug classes studied were excluded.

DATA SYNTHESIS

There are differing levels of adherence needed to maintain virologic suppression, depending on the ARV class used. The adherence level needed for unboosted protease inhibitors (PIs) has been established as greater than 95%, but recent studies have shown that greater than 80% adherence to boosted PIs may be sufficient. Nonnucleoside reverse transcriptase inhibitors (NNRTIs) could require lower adherence rates than boosted PIs; however, study results are varied and NNRTIs carry a potential for developing resistance with nonadherence. Studies assessing the adherence needed for raltegravir have yet to be performed.

CONCLUSIONS

Studies have shown differing levels of adherence needed among ARV classes of medications. With the advent of boosted PIs and potent medications, the amount of adherence needed has dropped since the 1990s. Although the current data are useful, there are discrepancies in the results due to the methods of adherence measurement. Knowing what adherence levels are needed is valuable in helping to determine the optimal ARV regimen for patients, given their adherence barriers. This knowledge can also help determine which patients require in-depth adherence counseling. Further research with a reliable method of measuring adherence is essential to determine adherence levels needed for newer ARV medications, including darunavir, etravirine, and raltegravir.

Treatment simplification in HIV-infected adults as a strategy to prevent toxicity, improve adherence, quality of life and decrease healthcare costs

Since the advent of highly active antiretroviral therapy (HAART), the treatment of human immunodeficiency virus (HIV) infection has become more potent and better tolerated. While the current treatment regimens still have limitations, they are more effective, more convenient, and less toxic than regimens used in the early HAART era, and new agents, formulations and strategies continue to be developed. Simplification of therapy is an option for many patients currently being treated with antiretroviral therapy (ART). The main goals are to reduce pill burden, improve quality of life and enhance medication adherence, while minimizing short- and long-term toxicities, reducing the risk of virologic failure and maximizing cost-effectiveness. ART simplification strategies that are currently used or are under study include the use of once-daily regimens, less toxic drugs, fixed-dose coformulations and induction-maintenance approaches. Improved adherence and persistence have been observed with the adoption of some of these strategies. The role of regimen simplification has implications not only for individual patients, but also for health care policy. With increased interest in ART regimen simplification, it is critical to study not only implications for individual tolerability, toxicity, adherence, persistence and virologic efficacy, but also cost, scalability, and potential for dissemination and implementation, such that limited human and financial resources are optimally allocated for maximal efficiency, coverage and sustainability of global HIV/AIDS treatment.

A collaborative awareness system for chronic disease medication adherence applied to HIV infection

Electronic reminder systems have been available for decades, yet medication adherence remains poor. Most systems rely on simple alarms and do not address other determinants of health-related behavior. This paper describes a collaborative awareness system for chronic disease medication adherence that relies on patient self-reflection and clinician support. Visualizations of adherence performance, including estimated plasma concentration graphs and a dynamic, personalized, disease-state simulation, are available to the patient (cell phone and internet media display) and clinician (computer) in real-time. The clinician can send asynchronous video messages of advice and encouragement to the patient regularly. A pilot was conducted with four HIV positive patients for four weeks. Three patients who started with suboptimal adherence improved (93.0% to 99.1%, 83.0% to 96.3%, and 63.9% to 81.3%). One patient who started with optimal medication adherence (>95%) maintained this level. All four patients appreciated the rich feedback and wanted to continue using the system.

Transmitted HIV-1 drug resistance among young men of color who have sex with men: a multicenter cohort analysis

BACKGROUND

Given the elevated potential for primary or transmitted drug resistance (TDR) among newly HIV-infected individuals, there is a need for a deeper understanding of the baseline resistance patterns present in young men of color who have sex with men.

METHODS

Genotypic data were collected for participants aged 13-24 who were enrolled from seven sites. Univariate and bivariate methods were used to describe the prevalence of TDR and characteristics associated with TDR.

RESULTS

Of the 296 individuals participating in the substudy, 145 (49%) had baseline genotypes. The majority of the individuals were African American (65%) and gay-identified (70%). There was significant variation in genotype availability by site (p < .001). Major surveillance drug resistance mutations were present in 28 subjects (19.3%); the majority were non-nucleoside reverse transcriptase inhibitor mutations (12.4%). Subjects with TDR were less likely to have used alcohol on 1 or more days in the prior 2 weeks. Location was not associated with acquisition of TDR.

CONCLUSIONS

There was a high rate of TDR in a geographically and racially diverse sample of HIV-infected young men of color who have sex with men. This represents a serious public health concern given the young age of this sample and the potential need for long-term antiretroviral therapy. These findings underscore the critical roles of both early case identification and secondary prevention.

Twice-daily versus once-daily antiretroviral therapy and coformulation strategies in HIV-infected adults: benefits, risks, or burden?

The recent development of once-daily antiretroviral agents and fixed-dose combination formulations has been an important development in antiretroviral regimen simplification. Recent studies indicate that once-daily antiretroviral regimens improve adherence, especially in antiretroviral-naïve patients and in difficult-to-treat populations, such as the homeless or marginally housed. However, there are potential risks with the higher peak and lower trough plasma drug concentrations that may result from certain once-daily formulations. Due to the multifactorial and complex nature of adherence behavior, clinicians' efforts to improve patient adherence should not be limited to prescribing once-daily regimens, but should also consider social support, side effect management, and adherence support tools, such as pillbox organizers and other targeted interventions. Additional research will clarify the benefits of once-daily and fixed-dose combination regimens on clinical and virologic outcomes. Comprehensive cost-benefit analysis of regimen simplification could help facilitate evidence-based decisions regarding antiretroviral regimen choices.

A systematic review of the impact of alcohol use disorders on HIV treatment outcomes, adherence to antiretroviral therapy and health care utilization

BACKGROUND

Alcohol use disorders (AUDs) are highly prevalent and associated with non-adherence to antiretroviral therapy, decreased health care utilization and poor HIV treatment outcomes among HIV-infected individuals.

OBJECTIVES

To systematically review studies assessing the impact of AUDs on: (1) medication adherence, (2) health care utilization and (3) biological treatment outcomes among people living with HIV/AIDS (PLWHA).

DATA SOURCES

Six electronic databases and Google Scholar were queried for articles published in English, French and Spanish from 1988 to 2010. Selected references from primary articles were also examined.

REVIEW METHODS

Selection criteria included: (1) AUD and adherence (N=20); (2) AUD and health services utilization (N=11); or (3) AUD with CD4 count or HIV-1 RNA treatment outcomes (N=10). Reviews, animal studies, non-peer reviewed documents and ongoing studies with unpublished data were excluded. Studies that did not differentiate HIV+ from HIV- status and those that did not distinguish between drug and alcohol use were also excluded. Data were extracted, appraised and summarized.

DATA SYNTHESIS AND CONCLUSIONS

Our findings consistently support an association between AUDs and decreased adherence to antiretroviral therapy and poor HIV treatment outcomes among HIV-infected individuals. Their effect on health care utilization, however, was variable.

A single tablet regimen is associated with higher adherence and viral suppression than multiple tablet regimens in HIV+ homeless and marginally housed people

BACKGROUND

Although, single-tablet regimen (STR) efavirenz, emtricibine, and tenofovir disoproxil fumarate (EFV/FTC/TDF) may be appealing in HIV-infected persons who are at high risk for nonadherence, the degree to which this simplified formulation affects adherence is not known. The virologic effectiveness of this STR in a potentially nonadherent population remains a concern, given the rapid selection of drug resistance seen with these drugs.

METHOD

We performed a prospective observational study assessing adherence and virologic response to EFV/FTC/TDF STR among a cohort of homeless and marginally housed individuals. We compared adherence and viral suppression to historical controls followed in the same cohort.

RESULTS

Adherence was higher in EFV/FTC/TDF STR regimen compared to non-one-pill-once-daily therapy (P = 0.006) after controlling for multiple confounders. Viral suppression (HIV RNA <50 copies/ml) was greater in EFV/ FTC/TDF STR than non-one-pill-once-daily regimens (69.2 versus 46.5%; P = 0.02), but there was no difference in viral suppression after controlling for adherence.

CONCLUSION

Once-daily EFV/TNF/FTC STR appears to be a reasonable option for individuals with multiple barriers to adherence. Randomized clinical trials addressing various therapeutic strategies for this patient population are needed.

Cobicistat (GS-9350): A Potent and Selective Inhibitor of Human CYP3A as a Novel Pharmacoenhancer

Cobicistat (3, GS-9350) is a newly discovered, potent, and selective inhibitor of human cytochrome P450 3A (CYP3A) enzymes. In contrast to ritonavir, 3 is devoid of anti-HIV activity and is thus more suitable for use in boosting anti-HIV drugs without risking selection of potential drug-resistant HIV variants. Compound 3 shows reduced liability for drug interactions and may have potential improvements in tolerability over ritonavir. In addition, 3 has high aqueous solubility and can be readily coformulated with other agents.

Short communication: Comparable safety and efficacy with once-daily versus twice-daily dosing of lopinavir/ritonavir tablets with emtricitabine + tenofovir DF in antiretroviral-naïve, HIV type 1-infected subjects: 96 week final results of the randomized trial M05-730

Sustained viral suppression with antiretroviral therapy improves clinical outcomes for HIV-infected individuals. Study M05-730 evaluated the long-term antiviral activity, safety, tolerability, emergence of resistance, and compliance with once-daily (QD) versus twice-daily (BID) lopinavir/ritonavir (LPV/r) combination therapy in treatment-naïve, HIV-1-infected subjects through 96 weeks. Antiretroviral-naïve subjects with HIV-1 RNA levels >1000 copies/ml were randomized to LPV/r QD (N = 333) or BID (N = 331) with tenofovir DF and emtricitabine. Through 96 weeks, 77 subjects from each group discontinued prematurely; adverse or HIV-related events contributed to discontinuation of 36 subjects overall, with no significant differences between treatment groups. At 96 weeks, 216 QD subjects (64.9%) and 229 BID subjects (69.2%) had HIV-1 RNA <50 copies/ml (p = 0.249) by intent-to-treat analysis. Evaluation of the time to virologic failure indicated that 85.0% and 80.7% of QD and BID subjects, respectively, maintained virologic suppression through 96 weeks (p = 0.638). QD subjects demonstrated greater adherence levels. There were no significant differences in virologic response when subjects were analyzed according to baseline disease state. Emergence of postbaseline resistance mutations occurred at similar low rates in each dosing group. Diarrhea was the most common moderate-to-severe drug-related adverse event reported; the most common Grade 3+ laboratory abnormalities were elevations of total cholesterol and triglycerides, occurring with similar incidence regardless of LPV/r dosing frequency. QD dosing of LPV/r was associated with similar durability of viral suppression and low rates of genotypic resistance and treatment-limiting adverse events as compared with BID dosing in treatment-naïve subjects through 96 weeks of treatment.

Similar safety and efficacy of once- and twice-daily lopinavir/ritonavir tablets in treatment-experienced HIV-1-infected subjects at 48 weeks

OBJECTIVES

To compare the safety and antiviral activity of once (QD) or twice (BID) daily lopinavir/ritonavir (LPV/r) in combination with investigator-selected nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) in treatment-experienced subjects.

METHODS

Subjects failing treatment with HIV-1 RNA > 1000 copies per milliliter received LPV/r tablets 800/200 mg QD (n = 300) or 400/100 mg BID (n = 299) with investigator-chosen nucleoside/nucleotide reverse transcriptase inhibitors. Efficacy was determined by the intent-to-treat time to loss of virologic response (ITT-TLOVR) algorithm. Safety, tolerability, adherence, impact of baseline protease mutations on virologic response, and emergence of resistance on therapy were assessed.

RESULTS

Demographics were comparable across groups. By intent-to-treat time to loss of virologic response, 166 QD subjects (55.3%) and 155 BID subjects (51.8%) were responders at week 48 (P = 0.413), with similar mean increases in CD4 T-cell count. QD subjects demonstrated better adherence than BID subjects. The occurrence of treatment-related moderate/severe adverse events was comparable for all events except nausea, which was reported more frequently among BID-treated subjects. Emergence of new protease resistance mutations on treatment was similarly infrequent in both groups.

CONCLUSION

LPV/r dosed QD resulted in increased treatment adherence and was as efficacious as BID LPV/r while providing similar safety, tolerability, and limited resistance evolution.

Recent key advances in human immunodeficiency virus medicine and implications for China

In this article we summarize several recent major developments in human immunodeficiency virus treatment, prevention, outcome, and social policy change. Updated international guidelines endorse more aggressive treatment strategies and safer antiretroviral drugs. New antiretroviral options are being tested. Important lessons were learned in the areas of human immunodeficiency virus vaccines and microbicide gels from clinical studies, and additional trials in prevention, especially pre-exposure prophylaxis, are nearing completion. Insight into the role of the virus in the pathogenesis of diseases traditionally thought to be unrelated to acquired immunodeficiency syndrome has become a driving force for earlier and universal therapy. Lastly, we review important achievements of and future challenges facing China as she steps into her eighth year of the National Free Antiretroviral Treatment Program.

The impact of once-nightly versus twice-daily dosing and baseline beliefs about HAART on adherence to efavirenz-based HAART over 48 weeks: the NOCTE study

OBJECTIVE

To determine the impact of once-nightly versus twice-daily dosing and beliefs about highly active antiretroviral therapy (HAART) on adherence to efavirenz-based HAART in antiretroviral-naive patients.

METHODS

A multicenter, open-label, 48-week, randomized controlled trial. Participants were randomized to receive once nightly didanosine plus lamivudine, or twice-daily combivir (zidovudine plus lamivudine) both in combination with efavirenz. Medication Event Monitoring Systems were used to compile drug-dosing histories. Beliefs about HAART (necessity and concerns) were measured at baseline using validated questionnaires. Perceptions of HAART intrusiveness were assessed after 4 weeks.

RESULTS

Eighty-seven patients were randomized (44 once-nightly and 43 twice-daily). Overall adherence was higher among the once-nightly arm (P = 0.0327). Eighty-one percent once-nightly and 62% twice-daily patients persisted with treatment for 48 weeks (P = 0.0559). Regimen execution was similar between both arms. Participants were significantly less likely to persist with HAART if their initial concerns about HAART were high relative to their perceived need for treatment (P = 0.025).

CONCLUSIONS

The difference in adherence observed between once-nightly and twice-daily dosing was driven by a difference in persistence with treatment. Psychological preparation for starting HAART should address patients' perceptions of necessity for HAART and concerns about adverse effects to maximize persistence with treatment.

Unmet therapeutic needs in the new era of combination antiretroviral therapy for HIV-1

Significant advances in outcomes have been achieved with combination antiretroviral therapy (cART) in patients living with HIV. However, several ongoing needs remain with respect to the development of new treatments. The need for new or enhanced cART may become increasingly apparent as patients live longer with HIV and a greater proportion die from non-AIDS-related illnesses. Immunological response to cART is variable and immune failure occurs, despite virological control. Moreover, viral suppression can be incomplete due to insufficient antiviral efficacy, acquired or transmitted drug resistance, suboptimal pharmacokinetics/pharmacodynamics and lack of adherence. Chronic immune activation may continue even when viral replication is relatively restrained. Patients continue to experience cardiovascular and metabolic complications, due to disease, treatment and ageing. In addition, neurocognitive impairment and malignancy are important sources of ongoing morbidity despite cART. HIV also affects immune system senescence and bone turnover. This review discusses potential unmet needs with respect to these issues.

Epidemiology of treatment failure: a focus on recent trends

PURPOSE OF REVIEW

As antiretroviral therapy has been refined with the development of more potent agents and simpler regimens, fewer individuals experience treatment failure. This review will highlight recent trends in treatment failure and virologic resistance in the developed world and resource-limited settings.

RECENT FINDINGS

The goal of antiretroviral therapy in all individuals, regardless of prior treatment exposure or HIV drug resistance, is to achieve full suppression of viral replication with a viral load of less than 50 copies/ml. This goal has been made a reality by the development of newer agents and simpler, better tolerated regimens. Recent cohort studies have demonstrated improved virologic outcomes in the current antiretroviral era, with decreased rates of virologic failure and associated resistance. Improved tolerability has aided adherence, which remains a key determinant of treatment success. Cohorts in resource-limited settings report improved clinical and virologic outcomes as rollout of highly active antiretroviral therapy programs continues.

SUMMARY

There has been a reassuring decrease in the frequency of virological failure and drug resistance in the modern highly active antiretroviral therapy era. This observation provides an important incentive to strengthen support of antiretroviral therapy programs to optimize virological outcomes, particularly in resource-limited settings in which access to newer agents and laboratory monitoring may be needed to ensure sustainable success.

Patient-reported outcomes in virologically suppressed, HIV-1-Infected subjects after switching to a simplified, single-tablet regimen of efavirenz, emtricitabine, and tenofovir DF

A randomized, open-label, multicenter study was conducted to evaluate the therapeutic switch to a single-tablet formulation of efavirenz/emtricitabine/tenofovir DF (EFV/FTC/TDF) among virologically suppressed, HIV-1-infected subjects. Eligible subjects on stable antiretroviral therapy (ART) with HIV-1 RNA less than 200 copies per milliliter for 3 months or more were stratified by prior protease inhibitor (PI)- or non-nucleoside reverse transcriptase inhibitor (NNRTI)-based therapy and randomized (2:1) to EFV/FTC/TDF or to stay on their baseline regimen (SBR). Patient-reported measures were quality of life (QOL; SF-36 [version 2]), treatment adherence (visual analogue scale), preference of medication (POM), perceived ease of the regimen for condition (PERC), and a 20-item HIV symptom index. Overall, 203 subjects were randomized to EFV/FTC/TDF and 97 to SBR. Fifty-three percent of subjects had previously received a PI-based regimen; 47% an NNRTI-based therapy. Throughout the study, SF-36 summary scores did not differ significantly from baseline, regardless of previous ART or treatment allocation. Adherence was 96% or more in both groups at baseline and all subsequent study visits. At study conclusion, the EFV/FTC/TDF regimen was considered easier to follow than prior regimens by 97% and 96% of subjects previously receiving PI-based and NNRTI-based therapies, respectively. Overall, 91% of subjects switched to EFV/FTC/TDF indicated a preference over their prior therapy. Switching to EFV/FTC/TDF was associated with transient worsening/emergence of dizziness and sustained improvements in several other HIV-related symptoms. In conclusion, switching virologically suppressed, HIV-1-infected subjects from PI-based or NNRTI-based regimens to EFV/FTC/TDF was associated with maintained QOL and treatment adherence, and improved ease of use and treatment satisfaction.

Switch from a ZDV/3TC-based regimen to a completely once daily (QD) regimen of emtricitabine/tenofovir DF fixed dose combination plus a third QD agent (SONETT)

Objectives

To assess the efficacy and safety of a treatment switch from a twice-daily (BID) regimen containing zidovudine (ZDV) and lamivudine (3TC) plus a third agent to a once daily (QD) regimen containing the fixed-dose combination of tenofovir DF/emtricitabine (TDF/FTC, Truvada^®) plus a divergent third QD agent in HIV-1 infected patients.

Methods

Prospective, 48-week, non-randomised, single-group, open-label, study. Fifty-one patients on stable ZDV/3TC-containing HAART, with HIV-1 RNA < 50 copies/ml and CD4+ T-cell count > 50 cells/μl, were switched to TDF/FTC plus a third agent. Plasma HIV-1 RNA, CD4+ and CD8+ T-cell counts were assessed at baseline and weeks 4, 12, 24, 36 and 48 post-switch.

Results

During the 48-week study, 10 patients discontinued prematurely, including three due to adverse events (AEs). At week 48, plasma HIV-1 RNA was < 50 copies/ml in 40 patients (78.4%). No patient experienced virological failure (defined as HIV-1 RNA ≥50 copies/ml at two consecutive post-baseline measurements) during the study. Immunologic control was maintained, with no significant changes in CD4+ or CD8+ T-cell counts. A statistically significant improvement from baseline in haemoglobin level was observed at week 48 (median change 0.8 g/dl; p < 0.001). There was also a statistically significant decrease in total cholesterol concentration at week 48 (-26.0 mg/dl; p = 0.001) in a subset of patients (n = 22) entering the study with elevated total cholesterol. Treatment was well tolerated and no treatment-related grade 3 or 4 AEs were seen.

Conclusions

Results from this study support switching from a ZDV/3TC-containing HAART regimen to a completely QD regimen of TDF/FTC plus a third agent. Virologic and immunologic control are maintained, with apparent benefits in haemoglobin.