Simplicity and Efficacy of a Once-Daily Antiretroviral Regimen with Didanosine, Lamivudine, and Efavirenz in Naïve Patients: The VESD Study

Prevalence of drug resistance mutations in HAART patients infected with HIV-1 CRF06_cpx in Estonia

HIV-1 drug resistance mutations (DRMs) and substitutions were assessed after the failure of the first line non-nucleoside reverse transcriptase inhibitors (NNRTIs) + 2 nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) treatment regimens (efavirenz [EFV] + lamivudine[3TC] + zidovudine [ZDV] vs. EFV + 3TC + ddI) among the HIV-1 CRF06_cpx infected subjects in Estonia. HIV-1 genomic RNA was sequenced; DRMs and amino acid substitutions were compared in 44 treatment naïve and 45 first-line NNRTI + 2 NRTI treatment failed patients consisting of EFV + 3TC + ZDV (n = 17) and EFV + 3TC + didanosine[ddI] (n = 21) therapy failed sub-populations. At least one DRM was found in 78% of treatment experienced patients. The most common NRTI mutations were M184V (80%), L74V (31%), L74I (17%), K219E (9%), and M184I (9%), NNRTI mutations were K103N (83%), P225H (14%), L100I (11%), and Y188L (11%), reflecting generally the similar pattern of DRMs to that seen in treatment failed subtype B viruses. Sub-population analysis revealed that EFV + 3TC + ddI failed patients had more DRMs compared to EFV + 3TC + ZDV failed patients, especially the ddI DRM L74IV and several additional NNRTI DRMs. Additionally, CRF06_cpx specific mutation E179V and substitutions R32K, K122E, and V200AE were also detected in treatment experienced population. After the failure of the first-line EFV + 3TC + ddI therapy HIV-1 CRF06_cpx viruses develop additional NRTI and NNRTI mutations compared to EFV + 3TC + ZDV regimen. Therefore the usage of EFV + 3TC + ddI in this subtype decreases the options for next regimens containing abacavir, and NNRTI class agents.

Didanosine, lamivudine-emtricitabine and efavirenz as initial therapy in naive patients

There are currently several suitable and different antiretroviral regimens to start highly active antiretroviral therapy (HAART), and many clinicians and patients prefer once-daily therapy. The efficacy and potency of efavirenz (EFV) has been established in many clinical trials and cohort studies; its pharmacokinetics, allowing for a convenient once-daily administration, make EFV one of the first agents to be included in once-daily regimens in naive patients. The two nucleoside reverse transcriptase inhibitors (NRTIs) accompanying the third drug have become the central skeleton, or the 'backbone' of the therapeutic scheme. Among the different NRTI pairs, a didanosine-lamivudine (3TC) or emtricitabine backbone for combination antiretroviral therapy may be a good option compared with any current NRTI-combinations due to its security, tolerance and once-daily dose. In this article, we review the advantages and drawbacks of didanosine-XTC-EFV as the initial regimen of HAART in HIV-infected patients.

Patient reported outcome instruments used in clinical trials of HIV-infected adults on NNRTI-based therapy: a 10-year review

BACKGROUND

Patient-reported outcomes (PROs) may provide valuable information to clinicians and patients when choosing initial antiretroviral therapy.

OBJECTIVE

To identify and classify PRO instruments used to measure treatment effects in clinical trials evaluating NNRTIs.

METHODS

We conducted a structured literature review using PubMed to identify NNRTI trials published from March 2003 to February 2013. Studies identified--based on disease, instrument, PRO, and NNRTI medication terms were reviewed--to identify PRO instruments. Domains measured within each instrument were recorded to understand key areas of interest in NNRTIs.

RESULTS

Of 189 articles reviewed, 27 validated instruments were administered in 26 unique trials, with a mean of 1.9 instruments (median: 1; range: 1-7) per trial. The Medical Outcomes Study HIV Health Survey (MOS-HIV) was the most commonly used instrument (n = 8 trials). Seventeen trials (65%) included at least one multidimensional health-related quality of life (HRQL) instrument (HIV-targeted, n = 11; general, n = 8). Other validated instruments measured sleep (n = 5), depression (n = 5), anxiety (n = 4), psychiatric symptoms (n = 2), beliefs about HIV medications (n = 2), HIV symptoms (n = 1), and stress (n = 1).

CONCLUSIONS

Although review of recent NNRTI trials suggests a lack of consensus on the optimal PRO instruments, a typical battery is comprised of a multidimensional HRQL measure coupled with one or more symptom measures. Further work is needed to clarify advantages and disadvantages of using specific PRO instruments to measure relevant constructs and to identify the most useful batteries of instruments for NNRTI trials.

Efficacy and safety of once-daily nevirapine- or efavirenz-based antiretroviral therapy in HIV-associated tuberculosis: a randomized clinical trial

BACKGROUND

Nevirapine (NVP) can be safely and effectively administered once-daily but has not been assessed in human immunodeficiency virus (HIV)-infected patients with tuberculosis (TB). We studied the safety and efficacy of once-daily NVP, compared with efavirenz (EFV; standard therapy); both drugs were administered in combination with 2 nucleoside reverse-transcriptase inhibitors.

METHODS

An open-label, noninferiority, randomized controlled clinical trial was conducted at 3 sites in southern India. HIV-infected patients with TB were treated with a standard short-course anti-TB regimen (2EHRZ(3)/4RH(3); [2 months of Ethambutol, Isoniazid, Rifampicin, Pyrazinamide / 4 months of Isoniazid and Rifampicin] thrice weekly) and randomized to receive once-daily EFV at a dose of 600 mg or NVP at a dose of 400 mg (after 14 days of 200 mg administered once daily) with didanosine 250/400 mg and lamivudine 300 mg after 2 months. Sputum smears and mycobacterial cultures were performed every month. CD4+ cell count, viral load, and liver function test results were monitored periodically. Primary outcome was a composite of death, virological failure, default, or serious adverse event (SAE) at 24 weeks. Both intent-to-treat and per protocol analyses were done, and planned interim analyses were performed.

RESULTS

A total of 116 patients (75% [87 patients] of whom had pulmonary TB), with a mean age of 36 years, a median CD4+ cell count of 84 cells/mm(3), and a median viral load of 310 000 copies/mL, were randomized. At 24 weeks, 50 of 59 patients in the EFV group and 37 of 57 patients in the NVP group had virological suppression (P = .024). There were no deaths, 1 SAE, and 5 treatment failures in the EFV arm, compared with 5 deaths, 2 SAEs, and 10 treatment failures in the NVP arm. The trial was halted by the data and safety monitoring board at the second interim analysis. Favorable TB treatment outcomes were observed in 93% of the patients in the EFV arm and 84% of the patients in the NVP arm (P = .058).

CONCLUSIONS

Compared with a regimen of didanosine, lamivudine, and EFV, a regimen of once-daily didanosine, lamivudine, and NVP was inferior and was associated with more frequent virologic failure and death. Clinical Trials Registration. NCT00332306.

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.

Quality of life and adherence to HAART in HIV-infected patients

A review on adherence to highly active antiretroviral therapy and the quality of life of patients living with HIV in the scientific literature, indexed in MEDLINE between 1998 and 2008, was performed. Studies published in Portuguese, Spanish or English with patients over 18 years of age were included. Reviews, case reports and letters were excluded. Of the 21 studies found, 12 were included (three clinical trials, three prospective cohorts and six cross-sectional studies). The relationship between quality of life and treatment adherence remains controversial, despite descriptive studies indicating the possibility of a positive association. The results may have been influenced by the specific characteristics of the described clinical trials and do not show a consensus regarding the impact of treatment adherence on patients' quality of life.

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.

Efavirenz: a decade of clinical experience in the treatment of HIV

Efavirenz, a non-nucleoside reverse transcriptase inhibitor, has been an important component of the treatment of HIV infection for 10 years and has contributed significantly to the evolution of highly active antiretroviral therapy (HAART). The efficacy of efavirenz has been established in numerous randomized trials and observational studies in HAART-naive patients, including those with advanced infection. In the ACTG A5142 study, efavirenz showed greater virological efficacy than the boosted protease inhibitor (PI), lopinavir. Efavirenz is more effective as a third agent than unboosted PIs or the nucleoside analogue abacavir. Some, but not all, studies have suggested that efavirenz (added to two nucleoside reverse transcriptase inhibitors) is more effective than nevirapine. Virological and immunological responses achieved with efavirenz-based HAART have been maintained for 7 years. Dosing convenience predicts adherence, and studies have demonstrated that patients can be switched from PI-based therapy to simplified, once-daily efavirenz-based regimens without losing virological control. The one-pill, once-daily formulation of efavirenz plus tenofovir and emtricitabine offers a particular advantage in this regard. Efavirenz also retains a role after failure of a first PI-based regimen. Efavirenz is generally well tolerated: rash and neuropsychiatric disturbances are the most notable adverse events. Neuropsychiatric disturbances generally develop early in treatment and they tend to resolve with continued administration, but they are persistent and troubling in a minority of patients. Efavirenz has less effect on plasma lipid profiles than some boosted PIs. Lipodystrophy can occur under treatment with efavirenz but it may be reduced if the concurrent use of thymidine analogues is avoided. Efavirenz resistance mutations (especially K103N) can be selected during long-term treatment, underscoring the importance of good adherence. Recent data have confirmed that efavirenz is a cost-effective option for first-line HAART. In light of these features, efavirenz retains a key role in HIV treatment strategies and is the first-line agent recommended in some guidelines.

Short communication: oral lesions in HIV/AIDS patients undergoing HAART including efavirenz

Oral lesions (OL) have an important prognostic value for HIV/AIDS patients. However, the behavior of OL in HIV/AIDS patients undergoing highly active antiretroviral therapy including efavirenz (HAART/EFV) has not been documented. Our objective was to establish the prevalence of OL in HIV/AIDS patients undergoing HAART/EFV and to compare it with the prevalence of OL in patients undergoing antiretroviral therapy including a protease inhibitor (HAART/PI). Seventy-three HIV/AIDS patients undergoing antiretroviral treatment for at least for 6 months at "La Raza" Medical Center's Internal Medicine Unit (IMSS, Mexico City) were included. To detect OL, a detailed examination of oral soft tissues was performed in each patient. Patient records recorded gender, seropositivity time, route of contagion, antiretroviral therapy type and duration, CD4 lymphocyte count/ml, and viral load. Two groups were formed: 38 patients receiving HAART/EFV [two nucleoside analogue reverse transcriptase inhibitors (NARTI) plus efavirenz] and 35 patients receiving HAART/PI (two NARTIs plus one PI). OL prevalence was established in each study group. The Chi-square test was applied (p < 0.05(IC95%)). OL prevalence in the HAART/EFV group (32%) was lower (p < 0.007) than in the HAART/PI group (63%). Candidosis was the most prevalent OL in both groups. Herpes labialis, HIV-associated necrotizing periodontitis, xerostomia, hairy leukoplakia, and nonspecific oral sores were identified. The highest prevalence for all OL was found in the HAART/PI group. These findings suggest that HIV/AIDS patients undergoing HAART/EFV show a lower prevalence of oral lesions than patients undergoing HAART/PI.

Long-term assessment of didanosine, lamivudine, and efavirenz in antiretroviral-naive patients: 3-year follow-up

The aim of this study was to evaluate the long-term efficacy and safety of didadosine (ddI), lamivudine (3TC), and efavirenz (EFV). This was a follow-up to the VESD study, a 12-month open-label, observational, multicenter study of adult patients with HIV infection who started antiretroviral treatment with the ddI-3TC-EFV once-daily regimen. Of the 167 patients originally included, 106 patients remained on the same triple therapy at the end of the study (1 year), and they were offered an extra 24 months of follow-up; 96 were enrolled in this study (VESD-2). Seventy patients out of the initial cohort were still on the same regimen at month 36, with 97% of them with plasma viral load <50 copies /ml. An intention-to-treat analysis showed that the percentage of patients with plasma viral load <50 copies/ml was 73% at 36 months. CD4 cell counts increased 344 cells/microl over the 36 months. Safety and tolerance were good with no unexpected long-term toxicity. After 3 years of treatment with ddI-3TC-EFV, more than 40% of the patients were still receiving the initial antiretroviral therapy with sustained, durable immunovirological benefit and good acceptance. Long-term toxicity and virological failure were low.

Efficacy and safety of a once daily regimen with efavirenz, lamivudine, and didanosine, with and without food, as initial therapy for HIV Infection: the ELADI study

The combination of didanosine (ddI) and lamivudine (3TC) is attractive considering its low cost, potency, tolerability, and convenience (once daily administration), but it is not recommended as first-line therapy for HIV infection. A prospective, multicenter, open, comparative trial was conducted in HIV-infected, antiretroviral-naive persons in Spain who begun a QD regimen with efavirenz (EFV), 3TC, plus ddI, the latter with or without food. A total of 103 patients were recruited in the study. Median baseline CD4 count was 229 cells/microl and plasma HIV-RNA was 4.9 logs copies/ml. In an intent-to-treat analysis, 78 (75.8%) had undetectable viremia at week 48 of therapy, without significant differences when comparing patients on and without fasting ddI (75% vs. 76.6%, respectively). The mean CD4 increase was of 199 cells/microl, with no significant differences between groups. Overall, 29 adverse events were recorded in 23 patients, the majority associated with neuropsychiatric symptoms of EFV. Treatment was discontinued in 10 (9.7%) patients due to adverse events. Virological failure was recognized in only six patients, four taking ddI with and two without food (p = 0.3). Drug resistance mutations were recognised in four of them. Plasma ddI concentrations did not differ significantly between groups. Mitochondrial DNA within peripheral blood mononuclear cells tended to increase in most subjects over 48 weeks of therapy regardless of treatment group. A QD regimen with ddI, 3TC, and EFV shows potency and tolerance similar to that reported using other currently recommended regimens in drug-naive HIV-infected patients. Its efficacy does not seem to be compromised when ddI is administered with food. Therefore, this regimen merits further investigation in larger comparative trials.

Didanosine enteric-coated capsule: current role in patients with HIV-1 infection

Didanosine, which is a synthetic nucleoside analogue intracellularly phosphorylated to the active metabolite, inhibits the activity of HIV-1 reverse transcriptase by competing with the natural substrate. Currently, didanosine is mainly provided as an enteric-coated capsule. In vitro, the molecule is active against laboratory strains and clinical isolates of HIV-1 in resting and activated T cells and monocyte/macrophages. Didanosine may select for resistance mutations that may render the drug inactive against the virus; L74V and K65R remain as the main didanosine-related mutations. In vitro, phenotypic susceptibility to didanosine was decreased beyond a defined fold change clinical cut-off (1.7), and it is considered that genotypic resistance exists when five thymidine-associated mutations or four plus M184V are present. In vivo, clinical studies have shown that didanosine retains significant antiviral activity in patients who have up to five nucleoside analogue mutations at baseline. Didanosine is useful in patients with no previous therapy, as well as in experienced patients in whom one or more antiretroviral regimens has failed.Enteric-coated didanosine is taken once daily, its co-administration with food has been recently evaluated and a reduction of the efficacy of the antiretroviral treatment was not observed. Administered with lamivudine (or emtricitabine), it can be considered a good alternative for use in the nucleoside analogue backbone included in combination therapies for antiretroviral-naive patients. Didanosine could be used in initial treatments for patients intolerant of zidovudine, abacavir or tenofovir. It can be included in once-daily combination regimens, which are more convenient and patient friendly.Prospective, observational and open-label studies, as well as clinical trials (with durations between 24 and 96 weeks), have demonstrated the safety and efficacy of didanosine plus lamivudine (or emtricitabine) plus efavirenz (or nevirapine) in previously untreated HIV-1-infected patients. The administration of didanosine to treatment-experienced patients has been evaluated in two different contexts: patients in whom previous therapies have failed (rescue therapy) and those with controlled viraemia who are switched to a didanosine-containing regimen for simplification.Adverse events associated with the administration of didanosine have been well known since the initial clinical trials with the drug. Gastrointestinal intolerance, peripheral neuropathy and hyperamylasaemia/pancreatitis were the most frequently reported. In the highly active antiretroviral therapy (HAART) era, the rate of adverse events has decreased. The tolerability of didanosine has been clearly improved with the development of the enteric-coated capsule. Severe manifestations of mitochondrial toxicity, including lactic acidosis and abnormal fat distribution, are rare complications, and occur most frequently when didanosine is used in combination with stavudine.