Highly active antiretroviral therapy (HAART) has contributed to decreased mortality and morbidity associated with HIV/AIDS1, 2. Non-adherence to antiretroviral medications is associated with virological failure, clinical disease progression and mortality; therefore good adherence to HAART is a critical determinant of its success3. To maximize the likelihood of success, clinicians have increasingly considered adherence and adverse events (AEs) in their treatment decisions4, 5. Therapy simplification, including reduced pill count, is a regimen-related strategy to improve adherence6. z As a once-daily (QD) fixed dose combination, abacavir/lamivudine (ABC/3TC) has shown favorable efficacy and safety in conjunction with a variety of background therapies. The tolerability of QD dosing is mostly comparable to that of ABC and 3TC administered BID. However, at least one study noted a higher rate of hypersensitivity to abacavir (ABC HSR), including severe ABC HSR in subjects on the QD versus BID regimen7. The evaluation of safety endpoints, especially ABC HSR in a “real world” population is of particular interest, as the incidence of suspected HSR varies across studies. z The aim of the Abacavir Lamivudine Once-daily HIV Assessment (ALOHA) Study was to evaluate the short-term (12-week) safety of ABC/3TC (EPZICOM™) in antiretroviral-naïve subjects, when administered as a part of an investigator-selected HAART regimen. The study duration was based on the short window of time after initiation of ABC and 3TC during which safety endpoints associated with these drugs are known to occur. In addition to safety and tolerability, adherence, patient satisfaction and efficacy endpoints were also evaluated.

Background: Switching a thymidine analogue to a non-thymidine analogue or changing to a nucleoside-sparing regimen has been shown to partially reverse peripheral lipoatrophy. The current study evaluated both approaches. Methods: Subjects at 15 AIDS Clinical Trial Group sites receiving thymidine analogue stavudine- or zidovudine-containing regimens with plasma HIV RNA ≤500 copies/mL and lipoatrophy were prospectively randomized to: (i) switch the thymidine analogue to abacavir; (ii) discontinue all antiretrovirals and switch to lopinavir/ritonavir plus nevirapine (LPV/r+NVP); or (iii) delay switching for 24 weeks (ClinicalTrials.gov identifier: NCT00028314). Single-slice computer tomography of mid-thigh and abdominal fat and metabolic and virological/ immunological parameters were measured at baseline and weeks 24 and 48. Results: Among the 101 patients enrolled, there were significant subcutaneous thigh fat and subcutaneous abdominal tissue (SAT) increases over time and decreases in visceral adipose tissue to total adipose tissue (

VAT:

TAT) ratios for both interventions, and a decrease in VAT for abacavir. CD4 increased in the LPV/r+NVP arm. LPV/r+NVP had a significantly shorter time to grade 3 or higher toxicity (P = 0.007), but discontinuation rates were similar. Glucose levels did not change, but insulin decreased in the LPV/r+NVP arm. Lipids tended to increase in the LPV/r+NVP arm. Conclusions: Switching stavudine or zidovudine to a non-thymidine analogue or changing to a nucleoside reverse transcriptase inhibitor-sparing regimen is associated with qualitatively similar improvements in thigh fat, SAT and

VAT:

TAT ratio at 48 weeks. Abacavir also resulted in VAT reductions and LPV/r+NVP resulted in CD4 count increases. © The Author 2009. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved.

BACKGROUND:

The role of exposure to specific antiretroviral drugs on risk of myocardial infarction in human immunodeficiency virus (HIV)-infected patients is debated in the literature.

METHODS:

To assess whether we confirmed the association between exposure to abacavir and risk of myocardial infarction (MI) and to estimate the impact of exposure to other nucleoside reverse transcriptase inhibitors (NRTIs), protease inhibitors (PIs), and non-NRTIs on risk of MI, we conducted a case-control study nested within the French Hospital Database on HIV. Cases (n = 289) were patients who, between January 2000 and December 2006, had a prospectively recorded first definite or probable MI. Up to 5 controls (n = 884), matched for age, sex, and clinical center, were selected at random with replacement among patients with no history of MI already enrolled in the database when MI was diagnosed in the corresponding case. Conditional logistic regression models were used to adjust for potential confounders.

RESULTS:

Short-term/recent exposure to abacavir was associated with an increased risk of MI in the overall sample (odds ratios [ORs], 2.01; 95% confidence interval [CI], 1.11-3.64) but not in the subset of matched cases and controls (81%) who did not use cocaine or intravenous drugs (1.27; 0.64-2.49). Cumulative exposure to all PIs except saquinavir was associated with an increased risk of MI significant for amprenavir/fosamprenavir with or without ritonavir (OR, 1.53; 95% CI, 1.21-1.94 per year) and lopinavir with ritonavir (1.33; 1.09-1.61 per year). Exposure to all non-NRTIs was not associated with risk of MI.

CONCLUSION:

The risk of MI was increased by cumulative exposure to all the studied PIs except saquinavir and particularly to amprenavir/fosamprenavir with or without ritonavir and lopinavir with ritonavir, whereas the association with abacavir cannot be considered causal.

BACKGROUND:

Regimens containing three nucleoside reverse-transcriptase inhibitors offer an alternative to regimens containing nonnucleoside reverse-transcriptase inhibitors or protease inhibitors for the initial treatment of human immunodeficiency virus type 1 (HIV-1) infection, but data from direct comparisons are limited.

METHODS:

This randomized, double-blind study involved three antiretroviral regimens for the initial treatment of subjects infected with HIV-1: zidovudine-lamivudine-abacavir, zidovudine-lamivudine plus efavirenz, and zidovudine-lamivudine-abacavir plus efavirenz.

RESULTS:

We enrolled a total of 1147 subjects with a mean baseline HIV-1 RNA level of 4.85 log10 (71,434) copies per milliliter and a mean CD4 cell count of 238 per cubic millimeter were enrolled. A scheduled review by the data and safety monitoring board with the use of prespecified stopping boundaries led to a recommendation to stop the triple-nucleoside group and to present the results in the triple-nucleoside group in comparison with pooled data from the efavirenz groups. After a median follow-up of 32 weeks, 82 of 382 subjects in the triple-nucleoside group (21 percent) and 85 of 765 of those in the combined efavirenz groups (11 percent) had virologic failure; the time to virologic failure was significantly shorter in the triple-nucleoside group (P<0.001). This difference was observed regardless of the pretreatment HIV-1 RNA stratum (at least 100,000 copies per milliliter or below this level; P< or =0.001 for both comparisons). Changes in the CD4 cell count and the incidence of grade 3 or grade 4 adverse events did not differ significantly between the groups.

CONCLUSIONS:

In this trial of the initial treatment of HIV-1 infection, the triple-nucleoside combination of abacavir, zidovudine, and lamivudine was virologically inferior to a regimen containing efavirenz and two or three nucleosides.

La mortalidad relacionada a SIDA ha sido controlada, durante la última dÚcada, gracias a la introducción de la TARV altamente activa. Sin embargo, a poco de desarrollar el primer ITRN, comenzaron a describirse múltiples efectos adversos secundarios. Estos son, con frecuencia, el principal punto de preocupación para los pacientes infectados con VIH que están en terapia antiretroviral, dado que otro problemas como son las infecciones oportunistas han pasado a ser infrecuentes y el SIDA, a comportarse como una afección crónica. Un efecto colateral típico es la toxicidad mitocondrial, la que puede expresarse como una hiperlactatemia asintomático o una acidosis láctica que amenaza la vida. Otros efectos adversos de ITRN son lipodistrofia (un complejo síndrome morfometabólico), quizás una neuropatía periférica, pancreatitis y reacción de hipersensibilidad a abacavir. Esta revisión explora la fisiopatología, aspectos clínicos y opciones terapéutica para cada uno de los principales efectos laterales de los ITRN, excepto AZT.

Anti-HIV drug regimens have dramatically improved the rates of prevention of mother-to-child transmission (MTCT) of HIV in developed countries. However, little is known of the effectiveness of such regimens in developing countries, such as Botswana. This study will determine whether Trizivir (TZV), a single pill containing abacavir sulfate, lamivudine, and zidovudine (ABC/3TC/ZDV), or lopinavir/ritonavir (LPV/r) and lamivudine/zidovudine (3TC/ZDV) is more effective in reducing HIV-1 viral load and preventing MTCT among HIV infected pregnant women in Botswana.

A 38-year-old Caucasian woman with uncontrolled human immunodeficiency virus (HIV) infection was treated with highly active antiretroviral therapy (HAART) consisting of zidovudine, lamivudine, and nevirapine. Because her therapeutic response was inadequate, the HAART regimen was changed to abacavir, lamivudine, and lopinavir-ritonavir. Three months after this therapy was started, the patient developed progressive and notable hair loss. Her hair became fair and thin, and her appearance deteriorated considerably. Hair loss due to HAART was diagnosed. Lopinavir-ritonavir was stopped, and efavirenz was substituted; abacavir and lamivudine were continued. After 4 weeks, her hair growth substantially improved, as evidenced by rapid growth of new hair. Her general condition also improved. No relapse was observed with the new HAART regimen, and the patient's hair loss completely reversed in 8 weeks. Alopecia is a possible adverse event in HIV-infected patients treated with protease inhibitors, particularly indinavir. Our patient's severe and generalized alopecia was temporally related to the initiation and discontinuation of lopinavir-ritonavir. On the basis of the Naranjo adverse drug reaction probability scale, the adverse reaction was considered probable. Although generalized hair loss due to lopinavir-ritonavir is rare, clinicians should be aware of this potential adverse reaction of this widely used drug. If alopecia is severe or particularly distressing to the patient, the offending drug should be discontinued, and therapy with another HIV drug should be started.

BACKGROUND. The risk of myocardial infarction (MI) in patients with human immunodeficiency virus (HIV) infection has been assessed in 13 anti-HIV drugs in the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study. METHODS. Poisson regression models were adjusted for cardiovascular risk factors, cohort, calendar year, and use of other antiretroviral drugs and assessed the association between MI risk and cumulative (per year) or recent (current or in the past 6 months) use of antiretroviral drugs, with >30,000 person-years of exposure. RESULTS. Over 178,835 person-years, 580 patients developed MI. There were no associations between use of tenofovir, zalcitabine, zidovudine, stavudine, or lamivudine and MI risk. Recent exposure to abacavir or didanosine was associated with an increased risk of MI. No association was found between MI risk and cumulative exposure to nevirapine, efavirenz, nelfinavir, or saquinavir. Cumulative exposure to indinavir and lopinavir-ritonavir was associated with an increased risk of MI (relative rate [RR] per year, 1.12 and 1.13, respectively). These increased risks were attenuated slightly (RR per year, 1.08 [95% confidence interval {CI}, 1.02-1.14] and 1.09 [95% CI, 1.01-1.17], respectively) after adjustment for lipids but were not altered further after adjustment for other metabolic parameters. CONCLUSIONS. Of the drugs considered, only indinavir, lopinavir-ritonavir, didanosine, and abacavir were associated with a significantly increased risk of MI. As with any observational study, our findings must be interpreted with caution (given the potential for confounding) and in the context of the benefits that these drugs provide.

BACKGROUND:

Evidence from randomized controlled trials supports the use of triple therapy. Research is required on the effectiveness of quadruple therapy in comparison to this and the relative effectiveness of specific highly active antiretroviral therapy (HAART) combinations.

METHODS:

Antiretroviral-naive individuals (n = 53) with an HIV-1 viral load >100 000 copies/mL were randomized to receive three-drug HAART with zidovudine/lamivudine (Combivir) and efavirenz or quadruple therapy with zidovudine/lamivudine/abacavir (Trizivir) and efavirenz (quad regimen). Patients continued on HAART for 48 weeks with regular clinical and immunological assessment. Standard and ultrasensitive (<5 copies/mL) viral load testing was carried out.

RESULTS:

A DAVG (difference in averages) analysis of the fall in viral load and increase in CD4 count showed no significant differences between regimens. Triple therapy resulted in a -4.17 log change (95% CI, -4.48 to -3.85) and quadruple therapy in a -4.36 log change (95% CI, -4.68 to -4.03) in viral load. For CD4 counts, the triple therapy arm increased by 164 cells/mm(3) (95% CI 112-217) and the quadruple arm by 185 (95% CI, 133-237). In an intent-to-treat analysis, 77% of patients in the triple therapy group reached an undetectable viral load (<50 copies/mL) compared with 84.2% of the quadruple therapy group. For ultrasensitive viral load testing, 23% and 18% of each group, respectively, reached undetectable viral loads. The hazard ratio for attaining a viral load of <5 copies/mL was 0.59 (95% CI, 0.26-1.33) for quadruple versus triple therapy. Three individuals in the triple therapy arm and nine in the quadruple therapy arm discontinued treatment.

CONCLUSIONS:

No differences in any analyses were observed between a standard of care regimen (zidovudine/lamivudine and efavirenz) and the quad regimen (zidovudine/lamivudine/abacavir and efavirenz).