Elly A. M. Hassink

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 contributes to insulin resistance within 3 months of starting combination antiretroviral therapy

Background:Patients with antiretroviral therapy (ART)-associated lipodystrophy frequently have disturbances in glucose metabolism associated with insulin resistance. It is not known whether changes in body composition are necessary for the development of these disturbances in ART-naive patients starting treatment with different combination ART regimens. Methods:Glucose metabolism and body composition were assessed before and after 3 months of ART in a prospective randomized clinical trial of HIV-1-positive ART-naive men taking lopinavir/ritonavir within either a nucleoside reverse transcriptase inhibitor (NRTI)-containing regimen (zidovudine/lamivudine; n = 11) or a NRTI-sparing regimen (nevirapine; n = 9). Glucose disposal, glucose production and lipolysis were measured after an overnight fast and during a hyperinsulinaemic–euglycaemic clamp using stable isotopes. Body composition was assessed by computed tomography and dual-energy X-ray absorptiometry. Results:In the NRTI-containing group, body composition did not change significantly in 3 months; insulin-mediated glucose disposal decreased significantly (25%; P < 0.001); and fasting glycerol turnover increased (22%; P < 0.005). Hyperinsulinaemia suppressed glycerol turnover equally before and after treatment. The disturbances in glucose metabolism were not accompanied by changes in adiponectin or other glucoregulatory hormones. In contrast, glucose metabolism did not change in the NRTI-sparing arm. Glucose disposal significantly differed over time between the arms (P < 0.01). Conclusions:Treatment for 3 months with a NRTI-containing, but not a NRTI-sparing, regimen resulted in a 25% decrease in insulin-mediated glucose disposal and a 22% increase in fasting lipolysis. In the absence of discernable changes in body composition, NRTI may directly affect glucose metabolism, the mechanism by which remains to be elucidated.

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 .

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 cm2, 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

A prospective, randomized trial of structured treatment interruption for patients with chronic HIV type 1 infection

BACKGROUND Structured treatment interruption was evaluated in 74 patients who had been pretreated with antiretrovirals, consisting of 2 nucleoside reverse-transcriptase inhibitors (NRTIs) for 1 year followed by 3 years of highly active antiretroviral therapy containing a protease inhibitor. METHODS Patients with a CD4 cell count of > or =350 cells/microL and a plasma viral load of <50 copies/mL were randomized to 3 therapy arms: (1) continuous therapy, (2) CD4 cell count-guided theory, and (3) week-on/week-off (WOWO) therapy. The efficacy and safety of structured treatment interruption and antiretroviral use were evaluated in human immunodeficiency type 1 (HIV-1)-infected patients. The study end points were percentage of patients who developed AIDS or who died and a CD4 cell count of > or =350 cells/microL. Intergroup differences were analyzed using analysis of variance and Kruskal-Wallis tests. RESULTS Baseline characteristics at the start of the structured treatment interruption were similar. At week 48, no patient had died, and 1 patient in the WOWO group had an AIDS-defining condition. The proportions of patients with a CD4 cell count of > or =350 cells/microL were 100%, 87%, and 96% in treatment arms 1, 2, and 3, respectively. The percentages of weeks of antiretroviral use were 100%, 41.1%, and 69.8% in arms 1, 2, and 3, respectively. The adverse events were not significantly different among arms (P=.27). Thirty-one percent of patients in the WOWO group experienced virological failure. CONCLUSION WOWO therapy maintained a CD4 cell count of > or =350 cells/microL in almost all patients but was associated with high virological failures rates (possibly resulting from previous dual-NRTI therapy), indicating that this strategy is less useful. Receipt of CD4 cell count-guided therapy resulted in comparable clinical outcomes to continuous therapy and may save antiretroviral-associated costs, but this needs to be confirmed by a larger trial.

Nevirapine increases high-density lipoprotein cholesterol concentration by stimulation of apolipoprotein A-I production.

Objective—The purpose of this study was to investigate the mechanism by which the nonnucleoside reverse transcriptase inhibitor (NNRTI) nevirapine (NVP) increases high-density lipoprotein cholesterol (HDLc) in treatment-experienced human immunodeficiency virus-1 (HIV-1)–infected patients. Methods and Results—Twelve HIV-1 infected patients, with stably suppressed HIV-1 viral load using AZT/3TC/abacavir for ≥6 months, added NVP to their current antiretroviral regimen. Patients received a primed bolus infusion of the stable isotope L-[1-13C]-valine for 12 hours before, as well as 6 and 24 weeks after, the addition of NVP to study apolipoprotein A-I (apoA-I) kinetics. Absolute production rate (APR) and fractional catabolic rate (FCR) of apoA-I were calculated using SAAM-II modeling. Major HDLc-modulating enzymes were assessed. Plasma apoA-I and HDLc levels increased significantly after 24 weeks of treatment by, respectively, 13±4% (P=0.01) and 16±6% (P=0.015). Concomitantly, apoA-I production rate at 24 weeks increased by 17±7% (P=0.04). ApoA-I catabolism did not change. A modest increase of lecithin:cholesterol acyltransferase and cholesteryl ester transfer protein activity was observed. Conclusions—NVP increases apoA-I production, which contributes to the HDLc increase after introduction of NVP-containing regimens. In view of the potent antiatherogenic effects of apoA-I, the observed increase may contribute to the favorable cardiovascular profile of NVP.

Pharmacokinetics of Stavudine and Didanosine Coadministered with Nelfinavir in Human Immunodeficiency Virus-Exposed Neonates

ABSTRACT We evaluated the pharmacokinetics of stavudine (d4T) and didanosine (ddI) in neonates. Eight neonates born to human immunodeficiency virus-infected mothers were enrolled to receive 1 mg of d4T per kg of body weight twice daily and 100 mg of ddI per m2 once daily in combination with nelfinavir for 4 weeks after birth. Pharmacokinetic evaluations were performed at 14 and 28 days of age. For d4T, on days 14 and 28, the median areas under the concentration-time curves from 0 to 12 h (AUC0–12s) were 1,866 and 1,603, ng · h/ml, respectively, and the median peak concentrations (Cmaxs) were 463 and 507 ng/ml, respectively. For ddI, on days 14 and 28, the median AUC0–10s were 1,573 and 1,562 h · ng/ml, respectively, and the median Cmaxs were 627 and 687 ng/ml, respectively. Systemic levels of exposure to d4T were comparable to those seen in children, suggesting that the pediatric dose of 1 mg/kg twice daily is appropriate for neonates at 2 to 4 weeks of age. Levels of exposure to ddI were modestly higher than those seen in children. Whether this observation warrants a reduction of the ddI dose in neonates is unclear.

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.

Stavudine but not Didanosine as Part of HAART Contributes to Peripheral Lipoatrophy: A Substudy from the Antiretroviral Regimen Evaluation Study (ARES)

Abstract 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.

The 48-week efficacy of once-daily saquinavir/ritonavir in patients with undetectable viral load after 3 years of antiretroviral therapy.

To evaluate the efficacy and safety of once‐daily saquinavir‐soft‐gel‐capsules/ritonavir (SQV‐SGC/RTV) 1600 mg/100 mg plus dual nucleoside reverse transcriptase inhibitors (NRTIs) in HIV‐infected patients with plasma viral load (pVL) <50 HIV‐1 RNA copies/mL following 3 years of antiretroviral therapy.