The early effects of stavudine compared with tenofovir on adipocyte gene expression, mitochondrial DNA copy number and metabolic parameters in South African HIV-infected patients: a randomized trial

Fat Matters: Understanding the Role of Adipose Tissue in Health in HIV Infection

More than one-third of adults in the USA are obese and obesity-related disease accounts for some of the leading causes of preventable death. Mid-life obesity may be a strong predictor of physical function impairment later in life regardless of body mass index (BMI) in older age, highlighting the benefits of obesity prevention on health throughout the lifespan. Adipose tissue disturbances including lipodystrophy and obesity are prevalent in the setting of treated and untreated HIV infection. This article will review current knowledge on fat disturbances in HIV-infected persons, including therapeutic options and future directions.

Editor's Highlight: Comparative Renal Safety Assessment of the Hepatitis B Drugs, Adefovir, Tenofovir, Telbivudine and Entecavir in Rats

The aim of this study was to determine the relative safety of 4 antiviral drugs (telbivudine, tenofovir, adefovir, and entecavir) against hepatitis B virus with respect to kidney function and toxicity in male Sprague Dawley rats. The antiviral drugs were administered once daily for 4 weeks by oral gavage at ∼10 and 25-40 times the human equivalent dose. Main assessments included markers of renal toxicity in urine, magnetic resonance imaging (MRI) of kidney function, histopathology, and electron microscopic examination. Administration of adefovir at 11 and 28 mg/kg for 4 weeks caused functional and morphological kidney alterations in a time- and dose-dependent manner, affecting mainly the proximal tubules and suggesting a mechanism of toxicity related to mitochondrial degeneration/depletion. Of note, the observed adefovir-induced reduction of kidney function was not detected by the standard method of glomerular filtration rate (GFR) measurements (clearance rate of the endogenous marker, creatinine), thereby emphasizing the superiority of MRI in terms of sensitive detection of GFR in rats. For the low dose of 300 mg/kg of tenofovir, minor kidney effects such as nuclear enlargement in the tubular epithelium, and hyaline droplets accumulation were detected, which was also observed for the low dose (11 mg/kg) of adefovir. No assessments could be done at the higher dose of 600/1000 mg/kg tenofovir due to gastrointestinal tract toxicity which prevented treatment of the animals for longer than 1 week. Entecavir at 1 and 3 mg/kg and telbivudine at 600 and 1600 mg/kg caused no toxicologically relevant effects on the kidney.

Comparative effectiveness of tenofovir in treatment-naïve HIV-infected patients: systematic review and meta-analysis

INTRODUCTION

Benefits and harms of tenofovir disoproxil fumarate (TDF) in HIV-infected, antiretroviral treatment (ART)-naïve patients of any age have not been systematically reviewed since recent milestone trials were published.

METHODS

We searched MEDLINE, EMBASE, CENTRAL, SCI, LILACS, WHO GHL, and ClinicalTrials.gov for randomized controlled trials (RCTs) comparing TDF-based treatments with any other ART-regimen (last search 01/2015). Trial characteristics and results were extracted, risks of bias systematically assessed, and treatment effects synthesized in meta-analyses using random-effects models.

RESULTS

We included 22 RCTs (8297 patients). We found no differences between groups for mortality, AIDS, fractures, CD4 cell count, and virological failure; and inconclusive information due to inadequate reporting for cardiovascular events, renal failure, proteinuria, rash, and quality of life. Tenofovir disoproxil fumarate-based regimens significantly reduced total cholesterol (mean difference -18.42 mg/dl; 95% confidence interval [CI] -22.80 to -14.0), LDL-cholesterol (-9.53 mg/dl; -12.16 to -6.89), HDL-cholesterol (-2.97 mg/dl; -4.41 to -1.53), and triglycerides (-29.77 mg/dl; -38.61 to -20.92), bone mineral density (BMD) (hip: -1.41%; -1.87 to -0.94), and glomerular filtration rate (eGFR) (-3.47 ml/minute; -5.89 to -1.06) over 48 weeks of follow-up. Effects were similar in trials comparing fixed-dose TDF/FTC-based regimens with ABC/3TC-based regimens. We found no influence of baseline viral load on virological failure.

DISCUSSION

Moderate-quality evidence suggests similar effects of TDF-based treatment regimens and other ART on virological failure. Tenofovir disoproxil fumarate-based regimens are associated with a more favorable lipid profile, but with increased risk of reduced BMD and eGFR. Improved reporting quality is vital to allow assessment of clinical outcomes in future trials.

Changing utilization of Stavudine (d4T) in HIV-positive people in 2006-2013 in the EuroSIDA study

OBJECTIVES

The long-term side effects of stavudine (d4T) led to recommendations in 2009 to phase out use of this drug. We aimed to describe temporal patterns of d4T use across Europe.

METHODS

Patients taking combination antiretroviral therapy (cART) in EuroSIDA with follow-up after 1 January 2006 were included in the study. cART was defined as d4T-containing [d4T plus at least two other antiretrovirals (ARVs) from any class] or non-d4T-containing (at least three ARVs from any class, excluding d4T). Poisson regression was used to describe temporal changes in the prevalence of d4T use and factors associated with initiating d4T.

RESULTS

A total of 5850 patients receiving cART on 1 January 2006 were included in the current analysis, rising to 7768 patients on January 1 2013. During this time, the prevalence of d4T use fell from 11.2% to 0.7%, with an overall decline of 19% per 6 months [95% confidence interval (CI) 19-20%]. d4T use declined fastest in Northern Europe [26% (95% CI 23-29%) per 6 months], and slowest in Eastern Europe [17% (95% CI 16-19%) per 6 months]. In multivariable Poisson regression models, new d4T initiations decreased by 14% per 6 months [adjusted incidence rate ratio (aIRR) 0.86; 95% CI 0.80-0.91]. Factors associated with initiating d4T were residence in Eastern Europe (aIRR 4.31; 95% CI 2.17-9.98) versus other European regions and HIV RNA > 400 copies/mL (aIRR 3.11; 95% CI 1.60-6.02) versus HIV RNA < 400 copies/mL.

CONCLUSIONS

d4T use has declined sharply since 2006 to low levels in most regions; however, a low but persistent level of d4T use remains in Eastern Europe, where new d4T initiations post 2006 are also more common. The reasons for the regional differences may be multifactorial, but it is important to ensure that all clinicians treating HIV-positive patients are aware of the potential harmful effects associated with d4T.

Multicenter cohort study of diabetes mellitus and impaired fasting glucose in HIV-infected patients in China

BACKGROUND

As life expectancy increases, HIV-infected patients are facing a wide array of metabolic complications, including diabetes mellitus (DM) and impaired fasting glucose (IFG). However, little is known about the incidence of and risk factors for glycemic disorders in Chinese HIV-infected patients.

METHODS

Longitudinal data were pooled from a multicenter clinical trial of combination antiretroviral regimens between 2009 and 2010 across Mainland China. DM was defined as fasting glucose level ≥7.0 mmol/L and IFG as between 5.6 and 6.9 mmol/L on 2 separate measurements. We calculated the incidence densities of DM and IFG. Risk factors for DM and IFG were also identified.

RESULTS

Four hundred fifteen patients contributed 457.35 person-years of follow-up. The incidence densities of DM and IFG were 2.62 and 35.64 per 100 person-years, respectively. In a multivariate analysis, advanced age [adjusted hazard ratio (HR): 1.03, 95% confidence interval (CI): 1.01 to 1.04], hepatitis B virus coinfection (adjusted HR: 1.59, 95% CI: 1.06 to 2.38), and baseline fasting glucose (adjusted HR: 1.28, 95% CI: 1.00 to 1.63) were associated with DM and IFG.

CONCLUSIONS

A high incidence of DM and IFG was detected in Chinese HIV-infected patients receiving combination antiretroviral therapy. Clinicians should be aware of the potential for an increased risk of glycemic disorders in Chinese HIV-infected patients, particularly those of advanced age, with hepatitis B virus coinfection or high baseline fasting glucose.

A randomized clinical trial comparing metabolic parameters after 48 weeks of standard- and low-dose stavudine therapy and tenofovir disoproxil fumarate therapy in HIV-infected South African patients

OBJECTIVES

Low-dose stavudine therapy may have a lower toxicity profile compared with standard dose. A randomized controlled trial comparing these two doses of stavudine with tenofovir disoproxil fumarate (tenofovir DF) was performed to assess the effects on anthropometry, markers of inflammation, and lipid and glucose metabolism in Black South African patients.

METHODS

Sixty patients were randomized 1:1:1 to either standard-dose (30-40 mg) or low-dose (20-30 mg) stavudine or tenofovir DF (300 mg), each combined with lamivudine and efavirenz, for 48 weeks. Anthropometry, markers of inflammation, and lipid and glucose metabolism were assessed using standard techniques.

RESULTS

In all three treatment arms, there was a significant increase in lipid levels over the study period. At 48 weeks, fasting glucose level (P < 0.005) and homeostasis model assessment (HOMA) score (P < 0.05) increased significantly in the standard-dose stavudine arm, as did insulin and C-peptide levels in both the standard- and low-dose stavudine arms. At week 48, a significant decrease (P < 0.05) in adiponectin was noted in the standard-dose stavudine arm, but there was an increase (P < 0.005) in the tenofovir DF arm. In both the stavudine arms, significant increases in anthropometric measures occurred at 24 weeks but these decreased by week 48. Mitochondrial toxicities occurred in both the stavudine arms. Immunological and virological outcomes were similar for all three arms.

CONCLUSIONS

This study highlights the occurrence of metabolic abnormalities with both stavudine and tenofovir DF treatment. Awareness of the potential increased cardiovascular risk should be of concern with the use of both these therapies.