The Role of Adherence to Antiretroviral Therapy in the Management of HIV Infection

Buffering effects of general and medication-specific social support on the association between substance use and HIV medication adherence

The success of highly active antiretroviral therapy (HAART) among persons living with HIV is largely dependent on strict medication adherence. Recent research suggests that alcohol and other drug use (AOD) may be an important barrier to HAART adherence. In this study, we examined the impact of AOD on HAART adherence as well as the moderating effects of general and medication-specific social support. The data were collected as part of a longitudinal randomized control trial with 224 HIV-positive patients at an HIV primary care clinic in the northwestern United States. Findings indicated that AOD use was negatively associated with HAART adherence and that medication-specific (but not general) social support moderated the AOD-adherence association at 3 (but not at 6 or 9) months. Results indicate the importance of medication-specific social support to treat comorbid AOD use and HIV; implications for future research and intervention programs for HIV-positive AOD users are discussed.

Pharmacotoxicology of monocyte-macrophage nanoformulated antiretroviral drug uptake and carriage

Limitations inherent to antiretroviral therapy (ART) in its pharmacokinetic properties remain despite over 15 years of broad use. Our laboratory has pioneered a means to improve ART delivery through monocyte-macrophage carriage of nanoformulated drug-encapsulated particles (nanoART). To this end, our prior works sought to optimize nanoART size, charge, and physical properties for cell uptake and antiretroviral activities. To test the functional consequences of indinavir, ritonavir, and efavirenz formulations we investigated relationships between human monocyte and macrophage cytotoxicities and nanoART dose, size, surfactant, and preparation. Wet-milled particles were more cytotoxic to monocytes-macrophages than those prepared by homogenization; with concurrent induction of tumor necrosis factor-alpha. Interestingly, pure suspensions of indinavir and ritonavir at 0.5 mM, and efavirenz at 0.1 mM and 0.5 mM also proved cytotoxic. Individual surfactants and formulated fluconazole neither affected cell function or viability. Although nanoART did not alter brain tight junction proteins ZO-2 and occludin, 0. 5mM ritonavir formulations did alter brain transendothelial electric resistance. These results underscore the potential importance of evaluating the physicochemical and functional properties of nanoART before human evaluations.

Two-way text messaging for health behavior change among human immunodeficiency virus-positive individuals

BACKGROUND

text-messaging systems have been used to promote a range of health behaviors, including medication adherence among human immunodeficiency virus-positive individuals. However, little is currently known about the specific characteristics of messaging systems that promote user engagement.

OBJECTIVE

using data from a randomized controlled trial involving a pager-based text messaging system, this study sought to examine the overall usability of the system, user evaluation of the system, demographic and psychosocial correlates of usability, and its performance as an adherence assessment tool.

MATERIALS AND METHODS

the messaging system consisted of an alphanumeric pager capable of sending and receiving individualized text messages and the software necessary to program and track communication. The system was evaluated using behavioral outcomes (pager message response rate), self-report survey responses, focus group discussions, and data from electronic medication monitoring pill bottles.

RESULTS

Although the majority of participants reported that the system was effective in reminding them to take medication doses, the overall response rate to system messages was relatively low (42.8%) and dropped significantly over the course of the 3-month intervention period. In addition, user engagement did not differ significantly by most demographic and psychosocial variables.

CONCLUSIONS

the pager-based text messaging system was received well by participants and appears to be applicable to a broad population; however, the system did not actively engage all participants over the course of the trial. Future research should determine whether systems customized to personal preference in notification style, frequency, and user device can increase use and provide further assistance to achieve optimal medication adherence.

Perceived stigma among patients receiving antiretroviral treatment: a prospective randomised trial comparing an m-DOT strategy with standard-of-care in Kenya

HIV and AIDS remain highly stigmatised. Modified directly observed therapy (m-DOT) supports antiretroviral treatment (ART) adherence but little is known about its association with perceived stigma in resource-constrained settings. In 2003, 234 HIV-infected adults enrolled in a two-arm randomised trial comparing a health centre-based m-DOT strategy with standard self-administration of ART. Data on perceived stigma were collected using Berger's HIV stigma scale prior to starting ART and after 12 months. This was a secondary analysis to examine whether perceived stigma was related to treatment delivery. Perceived stigma scores declined after 12 months of treatment from a mean of 44.9 (sd=7.6) to a mean of 41.4 (sd=7.7), (t=6.14, P<0.001). No differences were found between the mean scores of participants in both study arms. Also, no difference in scores was detected using GLM, controlling for socio-demographic characteristics and baseline scores. Findings indicate that a well managed clinic-based m-DOT does not increase perceived HIV-related stigma.

Design of a randomized trial to evaluate the influence of mobile phone reminders on adherence to first line antiretroviral treatment in South India--the HIVIND study protocol

BACKGROUND

Poor adherence to antiretroviral treatment has been a public health challenge associated with the treatment of HIV. Although different adherence-supporting interventions have been reported, their long term feasibility in low income settings remains uncertain. Thus, there is a need to explore sustainable contextual adherence aids in such settings, and to test these using rigorous scientific designs. The current ubiquity of mobile phones in many resource-constrained settings, make it a contextually appropriate and relatively low cost means of supporting adherence. In India, mobile phones have wide usage and acceptability and are potentially feasible tools for enhancing adherence to medications. This paper presents the study protocol for a trial, to evaluate the influence of mobile phone reminders on adherence to first-line antiretroviral treatment in South India.

METHODS/DESIGN

600 treatment naïve patients eligible for first-line treatment as per the national antiretroviral treatment guidelines will be recruited into the trial at two clinics in South India. Patients will be randomized into control and intervention arms. The control arm will receive the standard of care; the intervention arm will receive the standard of care plus mobile phone reminders. Each reminder will take the form of an automated call and a picture message. Reminders will be delivered once a week, at a time chosen by the patient. Patients will be followed up for 24 months or till the primary outcome i.e. virological failure, is reached, whichever is earlier. Self-reported adherence is a secondary outcome. Analysis is by intention-to-treat. A cost-effectiveness study of the intervention will also be carried out.

DISCUSSION

Stepping up telecommunications technology in resource-limited healthcare settings is a priority of the World Health Organization. The trial will evaluate if the use of mobile phone reminders can influence adherence to first-line antiretrovirals in an Indian context.

96-Week Efficacy and Safety of Atazanavir, With and Without Ritonavir, in a HAART Regimen in Treatment-Naive Patients

This study assesses virologic response, safety, tolerability, and changes in health-related quality of life (HRQoL) in antiretroviral (ARV)-naive patients treated with 2 atazanavir (ATV)-based regimens over 96 weeks. Treatment-naive adult patients (n = 200) were randomized to receive either ATV 300 mg with ritonavir (RTV) 100 mg (ATV300/r, n = 95) or ATV 400 mg (ATV400; n = 105). At week 96, 75% of ATV300/r-treated and 70% of ATV400-treated patients achieved viral loads <400 copies/mL (difference estimate [95% confidence interval, CI] = 5.1 [-7.1 to 17.2]). Five and 20 patients, respectively, experienced virologic failure. Adverse event-related discontinuations occurred among 8% receiving ATV300/r and 3% receiving ATV400. Plasma lipid elevations were generally low. Both regimens were well tolerated and associated with sustained improvements in HRQoL. These findings demonstrate long-term efficacy, tolerability, and safety of both ATV300/r and ATV400 in ARV-naive patients through 96 weeks with improvements in HRQoL.

Alternative dosage of zidovudine in infants exposed to maternal human immunodeficiency virus infection

As part of the 076 protocol, ZDV was given to HIV-exposed neonates for the first 6 weeks of life. The dosage was 2 mg/kg every 6 hours. Frequent dosing can be a deterrent to regimen adherence. We report our experience, using 3 mg/kg every 8 hours in 155 eligible HIV-exposed neonates, none of whom became HIV infected. Maximum risk of transmission that could be missed by this cohort is approximately 2%, which is consonant with current transmission rates. ZDV at 3 mg/kg every 8 hours is noninferior to 2 mg/kg every 6 hours and easier to administer.

Comparative description of haplotype structure and genetic diversity of MDR1 (ABCB1) in HIV-positive and HIV-negative populations

Human P-glycoprotein (P-gp), encoded by MDR1 (ABCB1), is an efflux transporter with a wide specificity for substrates/drugs, including HIV protease inhibitors which are commonly used in HIV/AIDS treatment. Three single nucleotide polymorphisms (SNPs) in MDR1 have been shown to affect P-gp expression and function, and may affect HIV/AIDS treatment outcome: 1236C>T [G412G, exon-12], 2677G>T/A [A893S/T, exon-21] and 3435C>T [I1145I, exon-26]. In the present study, our aims were (i) to compare the 3-SNP MDR1 haplotype structure and genetic diversity between North American HIV-positive and HIV-negative individuals belonging to four major ethnic groups and (ii) to determine whether the haplotype structure and genetic diversity observed in these ethnically admixed populations differ from that in ethnically non-admixed populations. For these aims, we analyzed a cohort of 447 HIV/AIDS patients (White [n=193], Black [n=235], Hispanic [n=17], and Asian [n=2]). Results obtained for these patients were compared with the results for (i) HIV-negative individuals (n=356) and (ii) various HapMap and Environmental Genome Project populations. We observed that the genetic characteristics of MDR1 were largely consistent between HIV-positive and HIV-negative populations, but there were striking interethnic differences in the genetic characteristics of MDR1 in both populations. Although it appeared that the genetic characteristics of MDR1 were largely consistent between ethnically admixed and non-admixed populations, genetic characterization of the admixed populations remains to be done. Thus, our results provide useful comparative insights about the genetic characteristics of MDR1 that could be extrapolated across population groups worldwide. For a meaningful interpretation of these results regarding HIV/AIDS treatment outcome, MDR1 haplotype/diplotype structure data, genetic characterization of population admixture, and polymorphisms in other relevant drug transporter and/or metabolizing enzyme genes should be considered in future clinical studies.

First HAART in HIV-Infected Patients With High Viral Load: Value of HIV RNA Levels at 12 Weeks to Predict Virologic Outcome

The aim of this study is to identify the role of incomplete suppression during the first months of highly active antiretroviral treatment (HAART) to predict virologic failure in patients with high levels of HIV replication. In a retrospective, longitudinal, and multicenter study, response to HAART was assessed in treatment-naive adults with HIV RNA >100 000 copies/mL, and factors predicting failure were analyzed through regression analyses. A total of 118 patients were included. Virologic failure occurred more often in patients with >500 copies/mL at week 12 (Cox regression: Exp (B) 3.22; P = .02). HIV RNA >500 copies/mL at week 12 predicted incomplete virologic response (odds ratio [OR] = 9.33; P = .002] but not viral rebound. Major antiretroviral resistant mutations were present in 11 of 14 patients. HIV RNA >500 copies/mL at week 12 of first HAART predicts incomplete virologic response in patients with high levels of replication at baseline. Most patients carried resistance mutations at the time of failure.

Pill Burden in Low-Income Patients with Metabolic Syndrome and Diabetes

Background:

While pill burden can harm or overwhelm patients, very little is known about pill burden in patients with diabetes or metabolic syndrome.

Objective:

To determine the pill burden level in low-income patients with metabolic syndrome who were enrolled in a diabetes study that was trying to achieve recommended targets of therapy.

Methods:

A prospective chart review was performed on 145 patients enrolled in a diabetes study at Siouxland Community Health Center. Patients were considered to have metabolic syndrome if they had 3 or more of the following clinical risk factors: (1) type 2 diabetes mellitus; (2) dyslipidemia (triglycerides >150 mg/dL or high-density lipoprotein cholesterol <40 mg/dL for men and <50 mg/dL for women); (3) hypertension (blood pressure <130/80 mm Hg or receiving antihypertensive medication); and (4) obesity (body mass index >30 kg/m2). Pill burden was defined as the average number of prescribed administrations per day. Inhalers, ophthalmics, and glucose meters were counted by number of puffs, drops, or finger sticks per day. Average hemoglobin A1C (A1C) level was collected at baseline and at 12 months.

Results:

The results showed that 85.5% of patients in the diabetes study were classified as having metabolic syndrome. The total number of administrations per day was analyzed for 124 eligible patients. Patients had an average baseline pill burden of 8.5 and A1C of 8.6%. After being enrolled in the study for 12 months, patients' average pill burden endpoint increased to 13.1 and A1C was reduced to 7.0%. At the end of the study, 37.9% of patients were prescribed dual therapy for glucose control: 79% on antihypertensives, 70% on lipid-lowering agents, and 65% taking aspirin.

Conclusions:

Diabetes patients with metabolic syndrome are prescribed multiple drug therapies to control diabetes and other metabolic abnormalities. In this study, we concluded that the average pill burden was 13.1 in patients with glucose-controlled diabetes and metabolic syndrome.

Expanding antiretroviral options in resource-limited settings--a cost-effectiveness analysis

BACKGROUND

Current World Health Organization (WHO) guidelines for treatment of HIV in resource-limited settings call for 2 antiretroviral regimens. The effectiveness and cost-effectiveness of increasing the number of antiretroviral regimens is unknown.

METHODS

Using a simulation model, we compared the survival and costs of current WHO regimens with two 3-regimen strategies: an initial regimen of 3 nucleoside reverse transcriptase inhibitors followed by the WHO regimens and the WHO regimens followed by a regimen with a second-generation boosted protease inhibitor (2bPI). We evaluated monitoring with CD4 counts only and with both CD4 counts and viral load. We used cost and effectiveness data from Cape Town and tested all assumptions in sensitivity analyses.

RESULTS

Over the lifetime of the cohort, 25.6% of individuals failed both WHO regimens by virologic criteria. However, when patients were monitored using CD4 counts alone, only 6.5% were prescribed additional highly active antiretroviral therapy due to missed and delayed detection of failure. The life expectancy gain for individuals who took a 2bPI was 6.7-8.9 months, depending on the monitoring strategy. When CD4 alone was available, adding a regimen with a 2bPI was associated with an incremental cost-effectiveness ratio of $2581 per year of life gained, and when viral load was available, the ratio was $6519 per year of life gained. Strategies with triple-nucleoside reverse transcriptase inhibitor regimens in initial therapy were dominated. Results were sensitive to the price of 2bPIs.

CONCLUSIONS

About 1 in 4 individuals who start highly active antiretroviral therapy in sub-Saharan Africa will fail currently recommended regimens. At current prices, adding a regimen with a 2bPI is cost effective for South Africa and other middle-income countries by WHO standards.

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.

Simplification of antiretroviral therapy to a single-tablet regimen consisting of efavirenz, emtricitabine, and tenofovir disoproxil fumarate versus unmodified antiretroviral therapy in virologically suppressed HIV-1-infected patients

OBJECTIVE

To evaluate a simplification strategy for HIV-1-infected patients virologically suppressed on antiretroviral therapy (ART) by switching to a single-tablet regimen consisting of efavirenz/emtricitabine/tenofovir disoproxil fumarate (EFV/FTC/TDF).

DESIGN

: Prospective, randomized, controlled, open-label, multicenter study.

METHODS

Patients on stable ART with HIV-1 RNA <200 copies per milliliter for > or = 3 months were stratified by prior nonnucleoside reverse transcriptase inhibitor-based or protease inhibitor-based therapy and randomized (2:1) to simplify treatment to EFV/FTC/TDF or to stay on their baseline regimen (SBR). Efficacy and safety assessments were performed at baseline and at weeks 4, 12, 24, 36, and 48. Additional patient-reported outcomes included the following: adherence by visual analog scale, quality of life by SF-36 (v2) survey, HIV Symptom Index, and the Preference of Medication and Perceived Ease of the Regimen for Condition questionnaires.

RESULTS

Three hundred patients (EFV/FTC/TDF 203, SBR 97) were evaluated (prior protease inhibitor-based ART, 53%; nonnucleoside reverse transcriptase inhibitor-based ART, 47%). The arms were well balanced at baseline with 88% males, 29% blacks, and a mean age of 43 years; CD4 was 540 cells per cubic millimeter, 96% had HIV-1 RNA <50 copies per milliliter, and 88% were on their first ART regimen. Through 48 weeks, 89% vs. 88% in the EFV/FTC/TDF vs. SBR arms, respectively, maintained HIV-1 RNA <200 copies per milliliter by time to loss of virologic response algorithm (intent to treat, noncompleters = failures) with the difference (95% confidence interval) between arms of 1.1% (-6.7% to 8.8%), indicating noninferiority of EFV/FTC/TDF vs. SBR. Similarly, maintenance of HIV-1 RNA <50 copies per milliliter by time to loss of virologic response algorithm was 87% vs. 85% for EFV/FTC/TDF vs. SBR, respectively [difference (95% confidence interval) 2.6% (-5.9% to 11.1%)]. Discontinuation rates were similar (EFV/FTC/TDF 11%, SBR 12%); more discontinuations for adverse events occurred in the EFV/FTC/TDF arm vs. SBR (5% vs. 1%), most commonly for nervous system symptoms. More patients withdrew consent in the SBR arm vs. EFV/FTC/TDF (7% vs. 2%). Estimated glomerular filtration rate (by Modification of Diet in Renal Disease) remained unchanged over 48 weeks in both arms (median change < 1 mL.min.1.73 m). A decrease in fasting triglycerides was observed at 48 weeks in the EFV/FTC/TDF vs. SBR arm (-20 vs. -3.0 mg/dL; P = 0.035). Adherence of > or = 96% was reported by visual analog scale in both arms at baseline and at all study visits.

CONCLUSION

Simplification to EFV/FTC/TDF maintained high and comparable rates of virologic suppression vs. SBR through 48 weeks.

Adherence to antiretroviral medication in older adults living with HIV/AIDS: a comparison of alternative models

The CDC estimates that by 2015, half of all persons living with HIV/AIDS in the USA will be over the age of 50. Despite increasing HIV seroprevalence rates in older adults, most research examining adherence to antiretroviral therapy (ART) has focused on young HIV-infected persons and, in general, has been atheoretical in nature. This study examined two ART adherence conceptual frameworks to determine whether these models generalize to HIV-seropositive older adults. Two hundred and forty-four HIV-positive adults 50-plus years of age were recruited through AIDS service organizations in Ohio and New York. Participants completed a neuropsychological battery and an audio computer-assisted self-interview. FIML SEM analyses revealed that neuropsychological functioning was not associated with adherence. Fit indices supported a stress and coping model, with negative affect mediating the effects of social support and maladaptive coping on ART adherence. Results were consistent with stress and coping models and suggest that interventions intending to increase adherence to ART in HIV-infected older adults may be more effective if they address negative affect and enhance adaptive coping and social support.

Factors related to quality of life in treatment-adherent, successfully treated HIV patients in France

The objectives of this study were to document the psychosocial characteristics of treatment-adherent, successfully treated HIV patients and to examine the relationships between psychosocial variables. The sample was composed of 133 persons living with HIV, with optimal adherence to antiretroviral therapy and with no detectable viral load. The psychosocial profile of the cohort showed that participants had moderate levels of stress, used a wide range of strategies to adjust to their situation and perceived their social support to be good. As well, they evaluated their quality of life (Medical Outcome Study-HIV) as moderate. Quality of life in psychological domain is largely explained by perceived stress (53%). Quality of life in physical domain is largely dependent on discomfort reported arising from HIV-associated symptoms and treatment (39%). Findings suggest that treatment-adherent, successfully treated patients with HIV are still a fragile population, and that it is essential to provide interventions that reinforce their ways of coping.

Steady-state pharmacokinetics of abacavir in plasma and intracellular carbovir triphosphate following administration of abacavir at 600 milligrams once daily and 300 milligrams twice daily in human immunodeficiency virus-infected subjects

Abacavir (ABC) is administered either at 600 mg once daily (ABC 600 mg QD) or 300 mg twice daily (ABC 300 mg BID) in anti-human immunodeficiency virus (anti-HIV) combination therapy. Although ABC plasma pharmacokinetics following each regimen has been well defined, no study has directly compared the regimens with respect to pharmacokinetics of ABC's active intracellular anabolite, carbovir-triphosphate (CBV-TP). In an open-label, two-period, crossover study, 34 HIV-infected male and female subjects stabilized on antiretroviral regimens containing either ABC 600 mg QD or ABC 300 mg BID received their usual doses on days -1 and 1 and then switched regimens for days 2 to 11. Serial blood samples collected on days 1 and 11 were assayed for plasma ABC and intracellular CBV-TP concentrations using validated high-performance liquid chromatography-tandem mass spectrometry methods. Pharmacokinetic parameters were calculated using noncompartmental methods. Analysis of variance with a mixed-effect model was performed for treatment and gender comparisons. In 27 evaluable subjects, the regimens provided bioequivalent ABC daily areas under the concentration-time curve from 0 to 24 h (AUC(0-24)) and comparable CBV-TP concentrations at the end of the dosing interval (C(tau)). As expected, ABC QD resulted in 109% higher ABC maximum concentrations of drug in plasma (C(max)) than did ABC BID. ABC QD also resulted in 32% higher CBV-TP AUC(0-24) and 99% higher CBV-TP C(max) than did ABC BID. Females had a 38% higher weight-adjusted ABC AUC(0-24) and 81% higher weight-adjusted CBV-TP AUC(0-24) than did males. Virologic suppression was maintained during regimen switch, and no tolerability differences between regimens were observed. In conclusion, this study showed that ABC 600 mg QD and ABC 300 mg BID regimens led to similar intracellular CBV-TP C(tau) values, thus providing pharmacokinetic support for the interchangeability of these two regimens. Women had higher intracellular CBV-TP exposure than did men.

Program development for enhancing adherence to antiretroviral therapy among persons living with HIV

In this paper the development of a self-management program to optimize long-term adherence to antiretroviral therapy for people living with HIV/AIDS is presented. The program is based on intervention mapping: that is, a framework that facilitates the use of theory and empirical evidence in intervention development. In the preparatory phase we conducted a needs-assessment. The results of this phase were then used in the operational phase in which the program was elaborated as follow: in Step 1 we established program objectives; in Step 2 we translated theoretical methods into practical strategies; and in Step 3 we integrated the strategies into a self-management program which were designed to help individuals mobilize their skills to cope with their antiretroviral therapies (ART). These particular abilities are: ability to integrate ART in daily routine, to cope with side effects, to handle situations in which ART is difficult to take, to interact with health professionals and to maintain relationships with social contacts. To address individuals' resources and skills in conjunction with the experience of taking the medication, we developed two different modalities to deliver the intervention: direct support and virtual support. Direct support consists of four 45-minute individualized, face-to-face sessions with a health professional. The Web application involved at least four interactive sessions with a computer. This application was developed with the intention to support individuals in managing their therapy, in a punctual, real-time mode. Treatment adherence behavior is an indicator or gauge that can reveal problems in being able to manage the therapy.

Once-daily atazanavir/ritonavir versus twice-daily lopinavir/ritonavir, each in combination with tenofovir and emtricitabine, for management of antiretroviral-naive HIV-1-infected patients: 48 week efficacy and safety results of the CASTLE study

BACKGROUND

Atazanavir/ritonavir is as effective as lopinavir/ritonavir, with a more favourable lipid profile and less gastrointestinal toxicity, in treatment-experienced HIV-1-infected patients. We compared these two combinations directly in treatment-naive patients.

METHODS

In this open-label, international non-inferiority study, 883 antiretroviral-naive, HIV-1-infected patients were randomly assigned to receive atazanavir/ritonavir 300/100 mg once daily (n=440) or lopinavir/ritonavir 400/100 mg twice daily (n=443), in combination with fixed-dose tenofovir/emtricitabine 300/200 mg once daily. Randomisation was done with a computer-generated centralised randomisation schedule and was stratified by baseline levels of HIV RNA (viral load) and geographic region. The primary endpoint was the proportion of patients with viral load less than 50 copies per mL at week 48. The main efficacy analysis was done by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00272779.

FINDINGS

At week 48, 343 (78%) of 440 patients receiving atazanavir/ritonavir and 338 (76%) of 443 patients receiving lopinavir/ritonavir had achieved a viral load of less than 50 copies per mL (difference 1.7%, 95% CI -3.8 to 7.1). Mean increases from baseline in CD4 cell count were similar (203 cells per muL in the atazanavir/ritonavir group vs 219 cells per muL in the lopinavir/ritonavir group). 25 (6%) patients in the atazanavir/ritonavir group and 26 (6%) in the lopinavir/ritonavir group were virological failures by week 48. Only two patients, both in the atazanavir/ritonavir group, had non-polymorphic protease inhibitor resistance mutations emerge on treatment, which conferred phenotypic resistance to atazanavir in one patient. Serious adverse events were noted in 51 (12%) of 441 patients in the atazanavir/ritonavir group and in 42 (10%) of 437 patients in the lopinavir/ritonavir group. Fewer patients in the atazanavir/ritonavir group than in the lopinavir/ritonavir group experienced grade 2-4 treatment-related diarrhoea (10 [2%] vs 50 [11%]) and nausea (17 [4%] vs 33 [8%]). Grade 2-4 jaundice was seen in 16 (4%) of 441 patients in the atazanavir/ritonavir group versus none of 437 patients in the lopinavir/ritonavir group; grade 3-4 increases in total bilirubin were seen in 146 (34%) of 435 patients on atazanavir/ritonavir and in one (<1%) of 431 patients on lopinavir/ritonavir.

INTERPRETATION

In treatment-naive patients, atazanavir/ritonavir once-daily demonstrated similar antiviral efficacy to lopinavir/ritonavir twice-daily, with less gastrointestinal toxicity but with a higher rate of hyperbilirubinaemia.

Selecting anti-HIV therapies based on a variety of genomic and clinical factors

Motivation: Optimizing HIV therapies is crucial since the virus rapidly develops mutations to evade drug pressure. Recent studies have shown that genotypic information might not be sufficient for the design of therapies and that other clinical and demographical factors may play a role in therapy failure. This study is designed to assess the improvement in prediction achieved when such information is taken into account. We use these factors to generate a prediction engine using a variety of machine learning methods and to determine which clinical conditions are most misleading in terms of predicting the outcome of a therapy.

Results: Three different machine learning techniques were used: generative–discriminative method, regression with derived evolutionary features, and regression with a mixture of effects. All three methods had similar performances with an area under the receiver operating characteristic curve (AUC) of 0.77. A set of three similar engines limited to genotypic information only achieved an AUC of 0.75. A straightforward combination of the three engines consistently improves the prediction, with significantly better prediction when the full set of features is employed. The combined engine improves on predictions obtained from an online state-of-the-art resistance interpretation system. Moreover, engines tend to disagree more on the outcome of failure therapies than regarding successful ones. Careful analysis of the differences between the engines revealed those mutations and drugs most closely associated with uncertainty of the therapy outcome.

Availability: The combined prediction engine will be available from July 2008, see http://engine.euresist.org

Contact:rosen@il.ibm.com

Prediction of adherence to antiretroviral therapy: can patients' gender play some role? An Italian pilot study

Recent literature has shown that adherence to HAART is a multi-faceted phenomenon, which involves both behavioural and psychological features. Therefore, the results obtained so far, though promising, have not yet unambiguously identified the factors that could predict non-adherence. Since any support for strengthening the adherence should take into account the HIV+ patients' perception of both their state of health and their relational style, this study tried to identify some psychological characteristics involved in the adherence phenomenon. A self-administered battery of tests including the Attachment Style Questionnaire (ASQ) and the Multidimensional Health Locus of Control Form-C (MHLC-C) was administered to an Italian sample. Results showed significant gender differences between non-adherent and adherent subjects. Specifically, the psychological profile of non-adherent males seemed focused less on relational aspects and perceived relevance of physicians and of 'significant other people', whilst that of non-adherent females seemed more 'relationship-oriented'. This study means to encourage clinicians to plan specific, gender-focused support for enhancing adherence.

High-resolution anoscopy targeted surgical destruction of anal high-grade squamous intraepithelial lesions: a ten-year experience

PURPOSE

This study was designed to determine whether high-resolution anoscopy and targeted surgical destruction of anal high-grade squamous intraepithelial lesions is effective in controlling high-grade squamous intraepithelial lesions while preserving normal tissues.

METHODS

Retrospective review of 246 patients with high-grade squamous intraepithelial lesions treated with high-resolution anoscopy-targeted surgical destruction from 1996 to 2006, with at least one follow-up at a minimum two months with physical examination, high-resolution anoscopy, cytology, and biopsy when indicated.

RESULTS

Lesions were extensive in 197 patients (81 percent); 207 (84 percent) were men, and 194 (79 percent) were immunocompromised (HIV or other). Persistent disease occurred in 46 patients (18.7 percent), requiring planned staged therapy; 10 required surgery. Recurrent high-grade squamous intraepithelial lesions occurred in 114 patients (57 percent) at an average 19 (range, 3-92) months; 26 of these required surgery. All other patients were retreated in-office with high-resolution anoscopy-directed therapies. Complications were seen in nine patients (4 percent). Despite treatment, three patients progressed to invasive cancer (1.2 percent). At their last visit, 192 patients (78 percent) had no evidence of high-grade squamous intraepithelial lesions.

CONCLUSIONS

High-resolution anoscopy-targeted destruction combined with office-based surveillance and therapy is effective in controlling high-grade squamous intraepithelial lesions and is superior to reports of expectant management or traditional mapping procedures.