Assessment of weight gain in adult patients living with HIV receiving first-line dolutegravir-based or efavirenz-based ART regimens in routine care clinics in Tshwane district, South Africa: An observational study.

INTRODUCTION: Although dolutegravir (DTG) is deemed stable, safe, cost-effective, and clinically beneficial, it also carries the risk of side effects, including observed weight gain among patients on DTG-based antiretroviral therapy (ART) regimens. We compared weight changes among adults (≥18 years) initiating tenofovir disoproxil fumarate, lamivudine, and dolutegravir (TLD) or tenofovir disoproxil fumarate, emtricitabine, and efavirenz (TEE) regimens and those switching from TEE to TLD (TEE-to-TLD switchers) in three large primary care facilities in South Africa METHODS: We conducted a retrospective longitudinal record review using patient medical records, extracting relevant demographic and clinical data from October 2018 to June 2021 from randomly selected adults who initiated TLD or TEE (initiators) and adult TEE-to-TLD switchers. We assessed weight, body mass index (BMI), and percentage weight changes for both groups and fitted linear regression and generalized linear models to determine factors associated with weight and BMI change and percentage weight change ≥10%, respectively, among treatment initiators. We fitted linear mixed-effect models among TEE-to-TLD switchers to consider repeated measures. RESULTS: Of 860 initiators, 450 (52.3%) initiated on TEE and 410 (47.7%) on TLD, with median follow-up of 1.4 years and 1.0 year, respectively. At initiation, 43.3% on TEE and 40.8% on TLD were overweight or obese. TLD initiators had an adjusted higher mean weight gain of 1.6 kg (p < 0.001) and mean BMI gain of 0.51 kg/m2 (p < 0.001) than TEE initiators. Independent risk factors for higher mean weight and BMI included age ≥50 years, male, on ART for >12 months, initial BMI of <18.5 kg/m2, and CD4 counts <200 cells/µL. Of 298 TEE-to-TLD switchers, 36.6% were overweight or obese at TEE initiation. Comparing before and after TLD switch, TEE-to-TLD switchers had an adjusted mean weight of 1.2 kg less while on TLD (p = 0.026). Being overweight and CD4 counts >350 cells/µL were independent risk factors for lower weight gain after TLD switch. CONCLUSIONS: We report more weight gain among TLD than among TEE initiators, although to a lesser extent than previously reported. TEE-to-TLD switchers experienced less weight gain after TLD switch; return to health before receiving TLD may be a contributory factor. The current findings are reassuring for those switching to a DTG-based regimen.

Adverse events in Chinese human immunodeficiency virus (HIV) patients receiving first line antiretroviral therapy.

BACKGROUND: Although the global human immunodeficiency virus (HIV) epidemic has improved significantly due to antiretroviral treatment (ART), ART-related adverse events (AEs) remain an issue. Therefore, investigating the factors associated with ART-related AEs may provide vital information for monitoring risks. METHODS: A prospective cohort study was conducted among adult patients (aged 18 years or older) with HIV who received Tenofovir (TDF) + Lamivudine (3TC) + Efavirenz (EFV) as first-line ART regimens. All AEs during the first 12 months of therapy were recorded. Logistic regression analysis was used to identify variables associated with AEs. RESULTS: Four hundred seventy-four patients receiving TDF+ 3TC+ EFV ART regimens between March 2017 and October 2017 were included in the study analysis. Among them, 472 (99.6%) experienced at least one AE, 436 (92.0%) patients experienced at least one AE within 1 month of treatment, 33 (7.0%) between one and 3 months of treatment, and three (0.6%) patients after 3 months of treatment. The most commonly reported AE was nervous system (95.6%) related, followed by dyslipidemia (79.3%), and impaired liver function (48.1%). Patients with baseline body mass index (BMI) greater than 24 kg/m2 (adjusted OR 1.77, 95%CI 1.03-3.02), pre-existing multiple AEs (adjusted OR 2.72, 95%CI 1.59-4.64), and pre-existing severe AEs (adjusted OR 5.58, 95%CI 2.65-11.73) were at increased odds of developing a severe AE. Patients with baseline BMI greater than 24 kg/m2 (adjusted OR 2.72, 95%CI 1.25-5.89) were more likely to develop multiple AEs. CONCLUSION: The incidence of ART-related adverse events over a 12-month period in China was high. Baseline BMI greater than 24 kg/m2, pre-existing multiple AEs, and pre-existing severe AEs were shown to be independent risk factors for developing a severe AE.

Assessment of physical functioning and handling of tiotropium/olodaterol Respimat® in patients with COPD in a real-world clinical setting.

Background: Patients with chronic obstructive pulmonary disease (COPD) show signs of reduced physical activity from the early stages of the disease, impacting morbidity and mortality. Data suggest treatment with tiotropium, a long-acting muscarinic antagonist, and olodaterol, a long-acting ß2-agonist (LABA), as monotherapies and in combination, increases exercise capacity. This study assessed the effects of fixed-dose tiotropium/olodaterol (delivered via Respimat®) on physical function in Global Initiative for Chronic Obstructive Lung Disease A-D patients requiring long-acting dual bronchodilation treatment in a real-world setting. Methods: This open-label, single arm, noninterventional study measured changes in physical function in COPD patients treated with tiotropium/olodaterol 5/5 µg for approximately 6 weeks (between Visit 1 [baseline] and Visit 2). Primary end point was therapeutic success, defined as a minimum 10-point increase in Physical Functioning Questionnaire (PF-10) score. Secondary end points included change in PF-10 from Visit 1 to Visit 2, the patient's general condition (measured by Physician's Global Evaluation score) at Visit 1 and Visit 2, and patient satisfaction with treatment delivered via the Respimat® device (assessed by Patient Satisfaction Questionnaire) at study end. Results: Therapeutic success was observed in 51.5% of 1578 patients (95% confidence interval [CI] 49.0, 54.0) after approximately 6 weeks of treatment with tiotropium/olodaterol. Mean change in PF-10 score between Visit 1 and Visit 2 was 11.6 points (95% CI 10.7, 12.6). Patient general condition improved as indicated by a general improvement in scores between visits. Most patients were very satisfied or satisfied with tiotropium/olodaterol treatment (82.5%), inhalation (87.5%), and handling of Respimat® (85.2%). One percent of patients reported an investigator-defined drug-related adverse events (AE). Conclusion: Tiotropium/olodaterol treatment improved physical functioning in COPD patients. An associated increase in patient general condition was observed. Most patients were very satisfied or satisfied with tiotropium/olodaterol treatment, inhaling, and handling of the Respimat® device. No unexpected drug-related AE occurred.

Long-term cost-effectiveness of the fixed-dose combination of tiotropium plus olodaterol based on the DYNAGITO trial results.

PURPOSE: Combinations of long-acting bronchodilators are recommended to reduce the rate of COPD exacerbations. Evidence from the DYNAGITO trial showed that the fixed-dose combination of tiotropium + olodaterol reduced the annual rate of total exacerbations (P<0.05) compared with tiotropium monotherapy. This study aimed to estimate the cost-effectiveness of the fixed-dose combination of tiotropium + olodaterol vs tiotropium monotherapy in COPD patients in the French setting. PATIENTS AND METHODS: A recently developed COPD patient-level simulation model was used to simulate the lifetime effects and costs for 15,000 patients receiving either tiotropium + olodaterol or tiotropium monotherapy by applying the reduction in annual exacerbation rate as observed in the DYNAGITO trial. The model was adapted to the French setting by including French unit costs for treatment medication, COPD maintenance treatment, COPD exacerbations (moderate or severe), and pneumonia. The main outcomes were the annual (severe) exacerbation rate, the number of quality-adjusted life-years (QALYs), and total lifetime costs. RESULTS: The number of QALYs for treatment with tiotropium + olodaterol was 0.042 higher compared with tiotropium monotherapy. Using a societal perspective, tiotropium + olodaterol resulted in a cost increase of +€123 and an incremental cost-effectiveness ratio (ICER) of €2,900 per QALY compared with tiotropium monotherapy. From a French National Sickness Fund perspective, total lifetime costs were reduced by €272 with tiotropium + olodaterol, resulting in tiotropium + olodaterol being the dominant treatment option, that is, more effects with less costs. Sensitivity analyses showed that reducing the cost of exacerbations by 34% increased the ICER to €15,400, which could still be considered cost-effective in the French setting. CONCLUSION: Treatment with tiotropium + olodaterol resulted in a gain in QALYs and savings in costs compared with tiotropium monotherapy using a National Sickness Fund perspective in France. From the societal perspective, tiotropium + olodaterol was found to be cost-effective with a low cost per QALY.

Comparative safety and effectiveness of perinatal antiretroviral therapies for HIV-infected women and their children: Systematic review and network meta-analysis including different study designs.

BACKGROUND: Nearly all newly infected children acquire Human Immunodeficiency virus (HIV) via mother-to-child transmission (MTCT) during pregnancy, labour or breastfeeding from untreated HIV-positive mothers. Antiretroviral therapy (ART) is the standard care for pregnant women with HIV. However, evidence of ART effectiveness and harms in infants and children of HIV-positive pregnant women exposed to ART has been largely inconclusive. The aim of our systematic review and network meta-analysis (NMA) was to evaluate the comparative safety and effectiveness of ART drugs in children exposed to maternal HIV and ART (or no ART/placebo) across different study designs. METHODS: We searched MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials (inception until December 7, 2015). Primary outcomes were any congenital malformations (CMs; safety), including overall major and minor CMs, and mother-to-child transmission (MTCT; effectiveness). Random-effects Bayesian pairwise meta-analyses and NMAs were conducted. After screening 6,468 citations and 1,373 full-text articles, 90 studies of various study designs and 90,563 patients were included. RESULTS: The NMA on CMs (20 studies, 7,503 children, 16 drugs) found that none of the ART drugs examined here were associated with a significant increase in CMs. However, zidovudine administered with lamivudine and indinavir was associated with increased risk of preterm births, zidovudine administered with nevirapine was associated with increased risk of stillbirths, and lamivudine administered with stavudine and efavirenz was associated with increased risk of low birth weight. A NMA on MTCT (11 studies, 10,786 patients, 6 drugs) found that zidovudine administered once (odds ratio [OR] = 0.39, 95% credible interval [CrI]: 0.19-0.83) or twice (OR = 0.43, 95% CrI: 0.21-0.68) was associated with significantly reduced risk of MTCT. CONCLUSIONS: Our findings suggest that ART drugs are not associated with an increased risk of CMs, yet some may increase adverse birth events. Some ART drugs (e.g., zidovudine) effectively reduce MTCT.

Comprehensive assessment of the safety of olodaterol 5 µg in the Respimat® device for maintenance treatment of COPD: comparison with the long-acting ß2-agonist formoterol.

This analysis provides a comprehensive clinical assessment of the long-term safety of the licensed dose of olodaterol (5 µg once daily [QD] via Respimat® inhaler) in patients with chronic obstructive pulmonary disease by exploring the occurrence of acknowledged side effects of long-acting ß2-agonists as well as those included in the olodaterol and formoterol labels. We analysed pooled data from two replicate, double-blind studies of olodaterol (5 µg QD via Respimat®) compared to formoterol (12 µg twice daily [BID]) or placebo over 48 weeks (1222.13, NCT00793624; 1222.14, NCT00796653). Patients could continue their background treatment. The analysis considered adverse events (AEs) typically associated with ß2-agonists, including cardiovascular events, as well as administration-related events. Descriptive statistics were provided for the incidence of AEs and aggregated AEs. The analysis included 1379 patients: 460 placebo, 459 olodaterol and 460 formoterol; AEs were reported by 70.9, 71.7 and 69.1% of patients, respectively. Exposure-adjusted incidence rates of cardiac AEs (arrhythmia and myocardial ischaemia) and cough were numerically lower in the olodaterol group than the formoterol group, while nasopharyngitis, throat irritation, metabolism and psychiatric disorders were numerically higher in the olodaterol group. The most frequent event in the olodaterol group was nasopharyngitis (placebo 8.0%; olodaterol 12.9%; formoterol 10.0%). Except for cough (incidence rate ratio of 0.46 [95% confidence interval 0.24, 0.89] in favour of olodaterol), there were no significant differences between active groups. In conclusion, olodaterol 5 µg QD was well tolerated over 48 weeks with a typical ß2-agonist safety profile comparable to formoterol 12 µg BID.

Effectiveness and safety of generic version of abacavir/lamivudine and efavirenz in treatment naïve HIV-infected patients: a nonrandomized, open-label, phase IV study in Cali-Colombia, 2011-2012.

BACKGROUND: Generic drug policies are often associated with concerns about the quality and effectiveness of these products. Phase IV clinical trials may be a suitable design to assess the effectiveness and safety of generic drugs. The objective of this study was to describe the effectiveness and the safety of the generic abacavir/lamivudine and efavirenz in treatment-naïve HIV-infected patients. METHODS: A monocentric, nonrandomized, open-label, phase IV study in treatment naïve HIV-infected patients 18 years or older with indication to receive abacavir/lamivudine and efavirenz were recruited from a program that provides comprehensive outpatient consultation and continuing care. The primary end-point was to achieve viral load <40 copies/mL at 12 months after baseline to assess effectiveness. Secondary end-point of the study were 1) to asses increasing in T-CD4 lymphocytes levels as accompaniment to asses effectiveness, and 2) to assess both gastrointestinal, skin, and central nervous system symptoms, and lipid profile, cardiovascular risk, renal, and hepatic function as safety profile. Data were determined at baseline, 3, 6, and 12 months. Close clinical monitoring and pharmaceutical care were used for data collection. Wilcoxon matched-pairs signed-rank test was used to compare proportions or medians. RESULTS: Sixty patients were invited to participate in the study; 42 were enrolled and 33 completed the follow-up. Of the nine patients excluded from the study, only one was withdrawn due to adverse events. At 12 months, 31 of 42 patients (73.8 % in intention-to-treat analysis) achieved a viral load of HIV1 RNA <40 copies/mL. There was a significant increase (172 cells/mm3) in the median for CD4 T lymphocyte count. The adverse events were mild and met the safety profile for this antiretroviral regimen, mainly of central nervous system symptoms, skin rash, lipid abnormalities, and an increase of 2 % in the median of the percentage of cardiovascular risk. CONCLUSIONS: The clinical outcomes of generic version of abacavir/lamivudine and efavirenz in HIV treatment naïve patients showed the expected safety and effectiveness profile of proprietary ARV drugs. TRIAL REGISTRATION: Registro Público Cubano de Ensayos Clínicos (RPCEC) ID: RPCEC00000202 . Registered 19 November 2015.

Weekends-off efavirenz-based antiretroviral therapy in HIV-infected children, adolescents, and young adults (BREATHER): a randomised, open-label, non-inferiority, phase 2/3 trial.

BACKGROUND: For HIV-1-infected young people facing lifelong antiretroviral therapy (ART), short cycle therapy with long-acting drugs offers potential for drug-free weekends, less toxicity, and better quality-of-life. We aimed to compare short cycle therapy (5 days on, 2 days off ART) versus continuous therapy (continuous ART). METHODS: In this open-label, non-inferiority trial (BREATHER), eligible participants were aged 8-24 years, were stable on first-line efavirenz with two nucleoside reverse transcriptase inhibitors, and had HIV-1 RNA viral load less than 50 copies per mL for 12 months or longer. Patients were randomly assigned (1:1) to remain on continuous therapy or change to short cycle therapy according to a computer-generated randomisation list, with permuted blocks of varying size, stratified by age and African versus non-African sites; the list was prepared by the trial statistician and randomisation was done via a web service accessed by site clinician or one of the three coordinating trials units. The primary outcome was the proportion of participants with confirmed viral load 50 copies per mL or higher at any time up to the 48 week assessment, estimated with the Kaplan-Meier method. The trial was powered to exclude a non-inferiority margin of 12%. Analyses were intention to treat. The trial was registered with EudraCT, number 2009-012947-40, ISRCTN, number 97755073, and CTA, number 27505/0005/001-0001. FINDINGS: Between April 1, 2011, and June 28, 2013, 199 participants from 11 countries worldwide were randomly assigned, 99 to the short cycle therapy and 100 to continuous therapy, and were followed up until the last patient reached 48 weeks. 105 (53%) were men, median age was 14 years (IQR 12-18), and median CD4 cell count was 735 cells per µL (IQR 576-968). Six (6%) patients assigned to the short cycle therapy versus seven (7%) assigned to continuous therapy had confirmed viral load 50 copies per mL or higher (difference -1·2%, 90% CI -7·3 to 4·9, non-inferiority shown). 13 grade 3 or 4 events occurred in the short cycle therapy group and 14 in the continuous therapy group (p=0·89). Two ART-related adverse events (one gynaecomastia and one spontaneous abortion) occurred in the short cycle therapy group compared with 14 (p=0·02) in the continuous therapy group (five lipodystrophy, two gynaecomastia, one suicidal ideation, one dizziness, one headache and syncope, one spontaneous abortion, one neutropenia, and two raised transaminases). INTERPRETATION: Non-inferiority of maintaining virological suppression in children, adolescents, and young adults was shown for short cycle therapy versus continous therapy at 48 weeks, with similar resistance and a better safety profile. This short cycle therapy strategy is a viable option for adherent HIV-infected young people who are stable on efavirenz-based ART. FUNDING: UK National Institute for Health Research Health Technology Assessment; UK Medical Research Council; European Commission; PENTA Foundation; INSERM SC10-US19, France.

BREATHER (PENTA 16) short-cycle therapy (SCT) (5 days on/2 days off) in young people with chronic human immunodeficiency virus infection: an open, randomised, parallel-group Phase II/III trial.

BACKGROUND: For human immunodeficiency virus (HIV)-infected adolescents facing lifelong antiretroviral therapy (ART), short-cycle therapy (SCT) with long-acting agents offers the potential for drug-free weekends, less toxicity, better adherence and cost savings. OBJECTIVES: To determine whether or not efavirenz (EFV)-based ART in short cycles of 5 days on and 2 days off is as efficacious (in maintaining virological suppression) as continuous EFV-based ART (continuous therapy; CT). Secondary objectives included the occurrence of new clinical HIV events or death, changes in immunological status, emergence of HIV drug resistance, drug toxicity and changes in therapy. DESIGN: Open, randomised, non-inferiority trial. SETTING: Europe, Thailand, Uganda, Argentina and the USA. PARTICIPANTS: Young people (aged 8-24 years) on EFV plus two nucleoside reverse transcriptase inhibitors and with a HIV-1 ribonucleic acid level [viral load (VL)] of < 50 copies/ml for > 12 months. INTERVENTIONS: Young people were randomised to continue daily ART (CT) or change to SCT (5 days on, 2 days off ART). MAIN OUTCOME MEASURES: Follow-up was for a minimum of 48 weeks (0, 4 and 12 weeks and then 12-weekly visits). The primary outcome was the difference between arms in the proportion with VL > 50 copies/ml (confirmed) by 48 weeks, estimated using the Kaplan-Meier method (12% non-inferiority margin) adjusted for region and age. RESULTS: In total, 199 young people (11 countries) were randomised (n = 99 SCT group, n = 100 CT group) and followed for a median of 86 weeks. Overall, 53% were male; the median age was 14 years (21% ≥ 18 years); 13% were from the UK, 56% were black, 19% were Asian and 21% were Caucasian; and the median CD4% and CD4 count were 34% and 735 cells/mm(3), respectively. By week 48, only one participant (CT) was lost to follow-up. The SCT arm had a 27% decreased drug exposure as measured by the adherence questionnaire and a MEMSCap(™) Medication Event Monitoring System (MEMSCap Inc., Durham, NC, USA) substudy (median cap openings per week: SCT group, n = 5; CT group, n = 7). By 48 weeks, six participants in the SCT group and seven in the CT group had a confirmed VL > 50 copies/ml [difference -1.2%, 90% confidence interval (CI) -7.3% to 4.9%] and two in the SCT group and four in the CT group had a confirmed VL > 400 copies/ml (difference -2.1%, 90% CI -6.2% to 1.9%). All six participants in the SCT group with a VL > 50 copies/ml resumed daily ART, of whom five were resuppressed, three were on the same regimen and two with a switch; two others on SCT resumed daily ART for other reasons. Overall, three participants in the SCT group and nine in the CT group (p = 0.1) changed ART regimen, five because of toxicity, four for simplification reasons, two because of compliance issues and one because of VL failure. Seven young people (SCT group, n = 2; CT group, n = 5) had major non-nucleoside reverse transcriptase inhibitor mutations at VL failure, of whom two (n = 1 SCT group, n = 1 CT group) had the M184V mutation. Two young people had new Centers for Disease Control B events (SCT group, n = 1; CT group, n = 1). There were no significant differences between SCT and CT in grade 3/4 adverse events (13 vs. 14) or in serious adverse events (7 vs. 6); there were fewer ART-related adverse events in the SCT arm (2 vs. 14; p = 0.02). At week 48 there was no evidence that SCT led to increased inflammation using an extensive panel of markers. Young people expressed a strong preference for SCT in a qualitative substudy and in pre- and post-trial questionnaires. In total, 98% of the young people are taking part in a 2-year follow-up extension of the trial. CONCLUSIONS: Non-inferiority of VL suppression in young people on EFV-based first-line ART with a VL of < 50 copies/ml was demonstrated for SCT compared with CT, with similar resistance, safety and inflammatory marker profiles. The SCT group had fewer ART-related adverse events. Further evaluation of the immunological and virological impact of SCT is ongoing. A limitation of the trial is that the results cannot be generalised to settings where VL monitoring is either not available or infrequent, nor to use of low-dose EFV. Two-year extended follow-up of the trial is ongoing to confirm the durability of the SCT strategy. Further trials of SCT in settings with infrequent VL monitoring and with other antiretroviral drugs such as tenofovir alafenamide, which has a long intracellular half-life, and/or dolutegravir, which has a higher barrier to resistance, are planned. TRIAL REGISTRATION: Current Controlled Trials ISRCTN97755073; EUDRACT 2009-012947-40; and CTA 27505/0005/001-0001. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme (projects 08/53/25 and 11/136/108), the European Commission through EuroCoord (FP7/2007/2015), the Economic and Social Research Council, the PENTA Foundation, the Medical Research Council and INSERM SC10-US19, France, and will be published in full in Health Technology Assessment; Vol. 20, No. 49. See the NIHR Journals Library website for further project information.

Combined bronchodilators (tiotropium plus olodaterol) for patients with chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD), a respiratory disease characterized by a progressive decline in lung function, is considered to be a leading cause of morbidity and mortality. Long-acting inhaled bronchodilators, such as long-acting ß2 agonists (LABAs) or long-acting muscarinic antagonists (LAMAs), are the cornerstone of maintenance therapy for patients with moderate-to-very-severe COPD. For patients not sufficiently controlled on a single long-acting bronchodilator, a combination of different bronchodilators has shown a significant increase in lung function. Tiotropium, a once-daily dosing LAMA, demonstrated sustained improvements in lung function as well as improved health-related quality of life, reduced exacerbations, and increased survival without altering the rate of decline in the mean forced expiratory volume in 1 second (FEV1) with fairly tolerable side effects. Olodaterol is a once-daily dosing LABA that has proven to be effective in improving lung function, reducing rescue medication use, and improving dyspnea and health-related quality of life, as well as improving exercise endurance with an acceptable safety profile. The combination of olodaterol and tiotropium provided additional improvements in lung function greater than monotherapy with each drug alone. Several well-designed randomized trials confirmed that the synergistic effect of both drugs in combination was able to improve lung function and health-related quality of life without a significant increase in adverse effects. The objective of this paper is to review available evidence on the clinical efficacy and safety of tiotropium, olodaterol, and their combination in patients with COPD.

Markov model for characterizing neuropsychologic impairment and Monte Carlo simulation for optimizing efavirenz therapy.

The study was undertaken to develop a pharmacokinetic-pharmacodynamic model to characterize efavirenz-induced neuropsychologic impairment, given preexistent impairment, which can be used for the optimization of efavirenz therapy via Monte Carlo simulations. The modeling was performed with NONMEM 7.2. A 1-compartment pharmacokinetic model was fitted to efavirenz concentration data from 196 Ugandan patients treated with a 600-mg daily efavirenz dose. Pharmacokinetic parameters and area under the curve (AUC) were derived. Neuropsychologic evaluation of the patients was done at baseline and in week 2 of antiretroviral therapy. A discrete-time 2-state first-order Markov model was developed to describe neuropsychologic impairment. Efavirenz AUC, day 3 efavirenz trough concentration, and female sex increased the probability (P01) of neuropsychologic impairment. Efavirenz oral clearance (CL/F) increased the probability (P10) of resolution of preexistent neuropsychologic impairment. The predictive performance of the reduced (final) model, given the data, incorporating AUC on P01and CL /F on P10, showed that the model adequately characterized the neuropsychologic impairment observed with efavirenz therapy. Simulations with the developed model predicted a 7% overall reduction in neuropsychologic impairment probability at 450 mg of efavirenz. We recommend a reduction in efavirenz dose from 600 to 450 mg, because the 450-mg dose has been shown to produce sustained antiretroviral efficacy.

[Evidence-based therapeutic drug monitoring for efavirenz]. / Niveau de preuve du suivi thérapeutique pharmacologique de l'efavirenz.

The efavirenz, a non nucleoside reverse transcriptase inhibitor of HIV-1, presents a marked pharmacokinetics variability related to an intense hepatic metabolism. Efavirenz is also a potent inducer. Central nervous system (CNS) toxicity associated with efavirenz therapy is a major cause of non adherence and therefore treatment failure. The literature has been analyzed to evaluate the level of evidence of the interest of a therapeutic drug monitoring for efavirenz. Several studies have reported that an efavirenz plasma concentration >1 000 ng/mL is a predictive factor of the viral response. Efavirenz plasma concentrations >4 000 ng/mL were associated to an increase frequency of CNS side effects. CNS toxicity was also more frequent in patients carrying the 516G > T mutation (CYP2B6*6 allele), associated with a significantly greater efavirenz plasma exposure. Non-randomized studies have reported the interest of efavirenz therapeutic drug monitoring to optimize viral response and prevent CNS toxicity, allowing to suggest a level of evidence "recommended" for efavirenz.

Cytochrome P450 2B6 (CYP2B6) and constitutive androstane receptor (CAR) polymorphisms are associated with early discontinuation of efavirenz-containing regimens.

OBJECTIVES: Cytochrome P450 2B6 (CYP2B6) is responsible for the metabolic clearance of efavirenz and single nucleotide polymorphisms (SNPs) in the CYP2B6 gene are associated with efavirenz pharmacokinetics. Since the constitutive androstane receptor (CAR) and the pregnane X receptor (PXR) correlate with CYP2B6 in liver, and a CAR polymorphism (rs2307424) and smoking correlate with efavirenz plasma concentrations, we investigated their association with early (<3 months) discontinuation of efavirenz therapy. METHODS: Three hundred and seventy-three patients initiating therapy with an efavirenz-based regimen were included (278 white patients and 95 black patients; 293 male). DNA was extracted from whole blood and genotyping for CYP2B6 (516G → T, rs3745274), CAR (540C → T, rs2307424) and PXR (44477T → C, rs1523130; 63396C → T, rs2472677; and 69789A → G, rs763645) was conducted. Binary logistic regression using the backwards method was employed to assess the influence of SNPs and demographics on early discontinuation. RESULTS: Of the 373 patients, 131 withdrew from therapy within the first 3 months. Black ethnicity [odds ratio (OR) = 0.27; P = 0.0001], CYP2B6 516TT (OR = 2.81; P = 0.006), CAR rs2307424 CC (OR = 1.92; P = 0.007) and smoking status (OR = 0.45; P = 0.002) were associated with discontinuation within 3 months. CONCLUSIONS: These data indicate that genetic variability in CYP2B6 and CAR contributes to early treatment discontinuation for efavirenz-based antiretroviral regimens. Further studies are now required to define the clinical utility of these associations.

Neuropsychiatric symptoms associated with efavirenz: prevalence, correlates, and management. A neurobehavioral review.

The non-nucleoside analog reverse transcriptase inhibitor efavirenz is one of the most common components of HAART. Neuropsychiatric symptoms are frequently reported in patients taking efavirenz-based regimens. These symptoms are usually transient, although they can sometimes persist for up to two years after initiation of treatment. This review describes in detail the most common neuropsychiatric symptoms related to efavirenz, outlines relevant and recent findings on this agent, and suggests possible interventions based on neurobehavioral results. Different recommendations on the assessment of efavirenz-related adverse events are also provided.

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.