Insulin sensitivity in multiple pathways is differently affected during zidovudine/lamivudine-containing compared with NRTI-sparing combination antiretroviral therapy.

OBJECTIVE: The extent and manner by which HIV nucleoside reverse transcriptase inhibitors contribute to insulin resistance is unclear. We evaluated the effect of zidovudine/lamivudine (ZDV/3TC) on glucose metabolism. METHODS: combination antiretroviral therapy-naive men were randomized to lopinavir/ritonavir (LPV/r, 400/100 mg twice a day) + ZDV/3TC or LPV/r (533/133 mg twice a day) + nevirapine (NVP). Computerized tomography, dual-energy X-ray absorptiometry scans, and hyperinsulinemic euglycemic clamps using stable isotopes were performed before and after 3, 12, and 24 months of combination antiretroviral therapy. RESULTS: Insulin-stimulated peripheral glucose disposal decreased by 25% after 3 months in patients on zidovudine/lamivudine/lopinavir/ritonavir (ZDV/3TC/LPV/r) (P < 0.001) and this decreased rate persisted thereafter, followed by a transient decrease in insulin-mediated inhibition of lipolysis. In the nevirapine/lopinavir/ritonavir (NVP/LPV/r) group, hepatic insulin sensitivity had improved compared with baseline after 24 months. After the initial 3 months, limb fat decreased in the ZDV/3TC/LPV/r arm up to 24 months [-849 +/- 345 g (P = 0.017)], and visceral adipose tissue increased over 2 years [+36.2 +/- 13.3 cm2 (P = 0.009)]. In the NVP/LPV/r group, a generalized increase in fat mass was observed. CONCLUSIONS: Treatment with ZDV/3TC/LPV/r versus NVP/LPV/r differentially affects glucose and lipid metabolism. The ZDV/3TC/LPV/r regimen induced peripheral insulin resistance, a transient increase in basal lipolysis and a transient decrease in insulin-mediated inhibition of lipolysis, whereas hepatic insulin sensitivity improved with the NVP/LPV/r regimen.

First line zidovudine/lamivudine/lopinavir/ritonavir leads to greater bone loss compared to nevirapine/lopinavir/ritonavir.

OBJECTIVE: We studied changes in bone mineral density (BMD) and bone turnover after initiation of combination antiretroviral therapy (cART) and the contribution of zidovudine/lamivudine (ZDV/3TC) in particular. DESIGN: Randomized clinical trial comparing lopinavir/ritonavir(LPV/r) + ZDV/3TC with LPV/r + nevirapine (NVP) in 50 cART-naive men. METHODS: Dual energy X-ray absorptiometry (DXA) and quantitative computed tomography scans (QCT) were performed at baseline and 3, 12, and 24 months after cART initiation. Serum 25-hydroxy-vitamin D3, parathyroid hormone (PTH), osteocalcin, and urine deoxypyridinoline (DPD)/creatinine ratio were measured. RESULTS: BMD decreased rapidly in both femoral neck and lumbar spine after cART initiation. BMD loss during 24 months measured by DXA, but not by QCT, was greater in the ZDV/3TC/LPV/r group compared to the NVP/LPV/r group [femoral neck: -6.3% +/- 1.0% (P < 0.0001) compared to -2.3% +/- 0.9% (P = 0.01), between-group P = 0.0006); lumbar spine: -5.1% +/- 0.8% (P < 0.0001) compared to -2.6% +/- 0.7% (P = 0.0006), between-group P = 0.07]. Osteocalcin [+1.60 +/- 0.32 (P < 0.0001) and +1.81 +/- 0.29 (P < 0.0001) nmol/l] and the urine DPD/creatinine ratio [+1.35 +/- 0.44 (P = 0.0029) and +1.19 +/- 0.38 nmol/mmol (P = 0.0024)] increased in both groups over 24 months, with no significant difference between groups. PTH increased to a greater degree in the NVP/LPV/r group [+2.0 +/- 0.31 pmol/l (P < 0.0001)] compared to [+0.81 +/- 0.33 pmol/l (P = 0.021) in the ZDV/3TC/LPV/r group]. CONCLUSION: BMD in both femoral neck and lumbar spine decreased rapidly after initiation of cART, in parallel to an increase in bone turnover. The greater bone loss in the ZDV/3TC/LPV/r group compared to the NVP/LPV/r group suggests that ZDV/3TC contributes to this process. The PTH increase does not explain this greater bone loss.

Zidovudine/lamivudine for HIV-1 infection contributes to limb fat loss.

BACKGROUND: Lipoatrophy is known to be associated with stavudine as part of the treatment for HIV infection, but it is less clear if this serious side effect is also related to other nucleoside reverse transcriptase inhibitors like zidovudine. We aimed to determine whether zidovudine-sparing first-line antiretroviral therapy would lead to less lipoatrophy and other metabolic changes than zidovudine-containing therapy. METHODOLOGY/PRINCIPAL FINDINGS: Fifty antiretroviral therapy-naïve HIV-1 infected men with an indication to start antiretroviral therapy were included in a randomized single blinded clinical trial. Randomisation was between zidovudine-containing therapy (zidovudine/lamivudine+lopinavir/ritonavir) and zidovudine-sparing therapy (nevirapine+lopinavir/ritonavir). Main outcome measures were body composition assessed by computed tomography and dual-energy X-ray absorptiometry scan and lipid profile before and after 3, 12, 24 months of antiretroviral therapy. In the zidovudine/lamivudine+lopinavir/ritonavir group, from 3 months onward limb fat decreased progressively by 684+/-293 grams (estimated mean+/-standard error of the mean)(p = 0.02) up to 24 months whereas abdominal fat increased, but exclusively in the visceral compartment (+21.9+/-8.1 cm(2), p = 0.008)). In contrast, in the nevirapine+lopinavir/ritonavir group, a generalized increase in fat mass was observed. After 24 months no significant differences in high density lipoprotein and total/high density lipoprotein cholesterol ratio were found between both treatment groups, but total and low density lipoprotein cholesterol levels were higher in the nevirapine+lopinavir/ritonavir group (6.1+/-0.2 versus 5.3+/-0.2 and 3.6+/-0.1 versus 2.8+/-0.1 mmol/l respectively, p<0.05). Virologic response and safety were comparable in both groups. CONCLUSIONS/SIGNIFICANCE: Zidovudine/lamivudine+lopinavir/ritonavir, but not nevirapine+lopinavir/ritonavir in antiretroviral therapy-naïve patients, is associated with lipoatrophy and greater relative intraabdominal lipohypertrophy, suggesting that zidovudine/lamivudine contributes to both these features of lipodystrophy. These findings support to no longer consider zidovudine/lamivudine as one of the preferred possible components of first-line antiretroviral therapy where alternative treatments are available. TRIAL REGISTRATION: ClinicalTrials.gov NCT 00122226.

Increase in carotid artery intima-media thickness and arterial stiffness but improvement in several markers of endothelial function after initiation of antiretroviral therapy.

BACKGROUND: The risk of cardiovascular disease in human immunodeficiency virus (HIV)-infected patients is an increasing concern. We studied the changes in vascular properties after the initiation of combination antiretroviral therapy (cART) as well as the contribution of different drug classes. METHODS: cART-naive men were randomized to receive either lopinavir/ritonavir (LPV/r) plus zidovudine/lamivudine (ZDV/3TC) (n = 19) or LPV/r plus nevirapine (NVP) (n = 18). Carotid artery intima-media thickness (C-IMT), arterial stiffness (distensibility coefficients [DCs] and compliance coefficients [CCs] of the carotid, femoral, and brachial arteries; carotid elastic modulus; and augmentation index), and markers of endothelial function (soluble vascular cell adhesion molecule [sVCAM]-1, intercellular adhesion molecule [sICAM]-1, plasma von Willebrand factor (vWF) antigen, and plasminogen activator inhibitor-1 antigen) and inflammation (high-sensitivity C-reactive protein) were measured before the initiation of cART and after 3, 12, and 24 months of cART. RESULTS: C-IMT increased by 0.061 +/- 0.016 mm (P < .001) in the ZDV/3TC/LPV/r arm and by 0.044 +/- 0.018 mm (P = .012) in the NVP/LPV/r arm (data are estimated means +/- SEs). Femoral artery DC (-1.66 +/- 0.78 x 10(-3)/kPa [P = .035]) and CC (-0.11 +/- 0.053 mm(2)/kPa [P = .43]) decreased in the ZDV/3TC/LPV/r arm and femoral DC decreased in the NVP/LPV/r arm (-1.72 +/- 0.85 x 10(-3)/kPa [P = .046]), with no significant difference in C-IMT or arterial stiffness between arms. sVCAM-1, sICAM-1, and vWF levels decreased significantly in both groups. CONCLUSION: C-IMT and femoral artery stiffness increased after the initiation of cART, whereas several markers of endothelial function improved, regardless of the composition of cART. Trial registration. ClinicalTrials.gov identifier: NCT00122226 .

Stavudine but not didanosine as part of HAART contributes to peripheral lipoatrophy: a substudy from the Antiretroviral Regimen Evaluation Study (ARES).

PURPOSE: To objectively assess changes in body fat distribution in a subgroup of antiretroviral therapy-naïve participants in a randomized comparative trial of regimens including a nucleoside analogue backbone of didanosine with either lamivudine or stavudine. METHOD: Whole body dual-energy X-ray absorptiometry (DEXA) scans were performed at baseline and weeks 48 and 96 of therapy in all 19 patients from one of the sites participating in the Antiretroviral Regimen Evaluation Study (ARES). Patients had been randomized to receive nelfinavir/didanosine/stavudine (n = 8), nevirapine/didanosine/lamivudine (n = 7), or ritonavir-boosted saquinavir/didanosine/lamivudine (n = 4). RESULTS: In an intent-to-treat analysis, patients allocated to didanosine plus stavudine-containing treatment after 96 weeks had lost a median of 1,825 g (-26%) of total limb fat, as compared to a median gain of 1,639 (48%) and 403 (6%) g in those randomized to the didanosine/lamivudine plus nevirapine or saquinavir-containing regimens, respectively. These changes in limb fat were statistically significantly different when comparing patients allocated to stavudine-containing treatment with both of the other two treatment arms combined (p = .01). CONCLUSION: This study suggests that didanosine/lamivudine, when combined with either nevirapine or ritonavir-boosted saquinavir over 96 weeks of therapy, is possibly not associated with limb fat atrophy, in contrast to when treatment contained didanosine, stavudine, and nelfinavir combined.

Boosted versus unboosted indinavir with zidovudine and lamivudine in nucleoside pre-treated patients: a randomized, open-label trial with 112 weeks of follow-up (HIV-NAT 005).

INTRODUCTION: The use of HIV protease inhibitors (PIs) in a ritonavir (RTV)-boosted form is now common. However, randomized data comparing boosted with unboosted PI strategies are scarce. METHODS: This randomized, open-label trial compared indinavir (IDV) 800 mg three times daily with IDV/RTV 800/100 mg twice daily, both given with zidovudine (AZT)/lamivudine (3TC) twice daily in individuals with at least 3 months previous AZT experience. The primary endpoint was the time-weighted average change in HIV RNA from baseline. Designed as a 48-week study, follow-up continued until week 112. Primary analysis is by intention to treat. RESULTS: One hundred and three patients commenced therapy and are included in the analysis. Patients had a median of 29 months past nucleoside reverse transcriptase inhibitor (NRTI) exposure. Baseline median (interquartile range) log10 HIV RNA was 4.0 (3.3-4.5) and CD4+ T-cell count 166 (40-323) cells/microl. After 112-weeks of study there was no significant difference observed between arms in the mean (SD) change in time-weighted average HIV RNA from baseline (-1.6 [1.1] HIV RNA copies/week/ml three times daily arm; -1.4 [1.1] HIV RNA copies/week/ml twice daily arm; P = 0.3). Both arms were associated with substantial toxicity expressed as serious adverse events and study drug interruptions. The twice daily arm experienced greater dyslipidaemia. Mean (SD) changes in time-weighted CD4+ T-cell count from baseline were similar [88 (84) cells/week/microl three times daily arm; 70 [109] cells/week/microl twice daily arm; P = 0.3). CONCLUSIONS: RTV-boosted IDV 800/100 mg twice daily demonstrated comparable efficacy to unboosted IDV 800 mg three times daily dosing. Both regimens were associated with substantial toxicity. Use of lower doses of RTV-boosted IDV may result in better tolerability without loss of efficacy and warrant further research.

Dose-escalating study of the safety and pharmacokinetics of nelfinavir in HIV-exposed neonates.

The pharmacokinetics of nelfinavir (NFV) in neonates younger than 4 weeks of age was assessed. Three cohorts of HIV-exposed neonates were enrolled in cohorts to receive 15, 30, and 45 mg of NFV/kg twice daily in combination with stavudine and didanosine for 4 weeks after birth. Trough NFV concentrations (C(min)) were measured at 1 and 7 days of age. Intensive pharmacokinetic evaluations were performed at 14 and 28 days of age. The median NFV C(min) values in the 15 mg/kg (6 patients), 30 mg/kg (5), and 45 mg/kg (11) cohorts at 1, 7, 14, and 28 days of age were 0.19, 1.21, 0.51, and 0.33; 1.02, 3.18, 0.73, and 0.55; and 0.67, 3.21, 0.70, and 0.73 mg/L, respectively. The median area under the plasma concentration-versus-time curve values over 12 hours in the three cohorts at 14 and 28 days of age were 14.4 and 8.7, 19.4 and 15.8, and 23.4 and 18.5 (h. mg)/L, respectively. No serious adverse events were observed. In conclusion, the systemic exposure of NFV decreased after 7 days of age, possibly because of hepatic enzyme maturation, autoinduction of NFV metabolism, and/or changes in NFV absorption. The highly variable systemic exposure observed in the study indicates that therapeutic drug monitoring seems warranted to ensure adequate NFV dosing in this population.