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Ezetimibe, a promising lipid-lowering agent for the treatment of dyslipidaemia in HIV-infected patients with poor response to statins.

Objective:To assess the efficacy, safety, and pharmacokinetic interactions of ezetimibe in HIV-infected patients with poorly controlled antiretroviral-associated dyslipidaemia while taking pravastatin alone. Design:A prospective, open-label, one-arm study of 24 weeks duration. Patients and setting:Nineteen patients (18 on stable HAART), with low density lipoprotein (LDL)-cholesterol values of ≥ 130 mg/dl despite the use of pravastatin. Methods:Ezetimibe, 10 mg/day, was added to pravastatin 20 mg/day, while patients maintained the same antiretroviral regimen. Determinations of total, LDL-, and high density lipoprotein (HDL)-cholesterol, triglycerides, apoproteins, and inflammatory factors (homocystein and C-reactive protein) were performed at baseline, and at weeks 6, 12, and 24. Liver enzymes and creatinine phosphokinase were also assessed. Protease inhibitor (PI) or non-nucleoside reverse transcriptase inhibitor (NNRTI) Cmin was determined just before and 12 weeks after ezetimibe introduction. Results:At week 24, 61.5% of patients achieved the endpoint of the study (LDL-cholesterol < 130 mg/dl). Significant declines in mean total and LDL-cholesterol levels were observed between baseline and weeks 6, 12, and 24, irrespective of antiretroviral type (PI or NNRTI). Mean HDL-cholesterol and apoprotein A increased significantly. No patients discontinued therapy due to intolerance or presented toxicity of grade 2 or more. No differences were observed in lopinavir or nevirapine Cmin measured just before and 12 weeks after ezetimibe introduction. Conclusion:The addition of ezetimibe to ongoing pravastatin seems to be an effective and safe option for HIV-infected patients not achieving the NCEP ATPIII LDL-cholesterol goals while receiving a statin alone. Its high tolerability and the lack of interactions with the cytochrome CYP3A4 indicate that ezetimibe will not increase the risk of toxicity or pharmacokinetic interactions with antiretrovirals.

Monitoring Atazanavir Concentrations With Boosted or Unboosted Regimens in Hiv-infected Patients in Routine Clinical Practice

Although atazanavir pharmacokinetics and pharmacodynamics are related, the atazanavir plasma trough concentrations of patients on regimens that are not boosted by low doses of ritonavir may not be high enough to maintain viral suppression. In this cross-sectional study, the percentage of patients with atazanavir trough concentrations lower than the proposed minimum effective concentration was compared between HIV-infected patients receiving antiretroviral therapy with ritonavir-boosted (ATV/r, n = 31) or unboosted (ATV, n = 54) atazanavir in clinical practice. Blood samples were drawn 21 to 25 hours after the last atazanavir dose. Drug concentrations in plasma were determined by high-performance liquid chromatography and considered suboptimal if they were lower than 0.15 mg/L or potentially toxic if higher than 0.85 mg/L. The median (interquartile range) atazanavir concentration was 0.711 (0.394-0.914) mg/L in patients receiving ATV/r and 0.121 (0.052-0.209) mg/L in patients receiving ATV (P < 0.001). None of the patients receiving ATV/r and 62.9% of the subjects receiving ATV showed drug concentrations below 0.15 mg/L (odds ratio, 2.7; 95% confidence interval, 1.9-3.8; P < 0.001). In contrast, atazanavir concentrations were higher than 0.85 mg/L in 32.2% of the patients receiving ATV/r compared with 3.7% of the subjects receiving ATV (odds ratio, 8.7; 95% confidence interval, 2.0-37.2; P = 0.001). Atazanavir and total bilirubin concentrations in plasma were correlated. In conclusion, atazanavir trough concentrations may be lower than the proposed minimum effective concentration in a considerable percentage of HIV-infected patients receiving antiretroviral therapy with unboosted atazanavir. Therapeutic drug monitoring may be useful in this setting.

Comparison of an oleic acid enriched-diet vs NCEP-I diet on LDL susceptibility to oxidative modifications

Objective: The objective of this trial was to compare the effect on the susceptibility of plasma Low Density Lipoprotein (LDL) to oxidative modifications of consumption of two oleic rich diets, prepared with two different plant oils, virgin olive oil (OL)1 and refined high monounsaturated fatty acids (MUFA sunflower oil (SU)), with the susceptibility of plasma LDL to oxidation after an National Cholesterol Education Program step 1 (NCEP-I) phase diet.Design: A randomized crossover design.Subjects and interventions: Twenty-two healthy normolipidemic young males consumed an NCEP-I diet for a 4-week period. Subjects were then assigned to two diets each of 4-weeks duration. Group one was placed on an olive oil enriched diet (40% fat, 22% MUFA) followed by a 4-week period of a MUFA diet enriched in sunflower oil (40% fat, 22% MUFA). In group two, the order of the diets was reversed.Results: Both MUFA diets induced a decrease in saturated (14:0, 16:0, and 18:0) and an increase in monounsaturated and polyunsaturated n-6 (18:2, 20:3, and 20:5) plasma LDL-phospholipid fatty acids, compared to the NCEP-I diet (P<0.01). No significant differences in lag times were observed between the olive oil and the NCEP-I diet periods. However there was a greater inhibition time (P<0.001) when subjects consumed the MUFA rich sunflower oil diet compared to the NCEP-I diet. These differences were probably related to the relative enrichment of plasma LDL particles in α-tocopherol due to the high vitamin E content of the MUFA-rich sunflower oil. Indeed, the α-tocopherol content was positively correlated with lag time (r=0.338; P<0.008).Conclusion: Our findings suggest that changes in plasma LDL α-tocopherol content with practical solid-food diets can decrease its susceptibility to oxidation.Sponsorship: This work has been supported by grants from the Investigaciones de la Seguridad Social (FIS 92/0182, to Francisco Pérez Jiménez); and from Koype Co, Andújar, Jaén, Spain.European Journal of Clinical Nutrition (2000) 54, 61–67

Simultaneous Population Pharmacokinetic Model for Lopinavir and Ritonavir in HIV-Infected Adults

AbstractBackground: Lopinavir is a protease inhibitor indicated for the treatment of HIV infection. It is coformulated with low doses of ritonavir in order to enhance its pharmacokinetic profile. After oral administration, plasma concentrations of lopinavir can vary widely between different HIV-infected patients. Objective: To develop and validate a population pharmacokinetic model for lopinavir and ritonavir administered simultaneously in a population of HIV-infected adults. The model sought was to incorporate patient characteristics influencing variability in the drug concentration and the interaction between the two compounds. Methods: HIV-infected adults on stable therapy with oral lopinavir/ritonavir in routine clinical practice for at least 4 weeks were included. A concentration-time profile was obtained for each patient, and blood samples were collected immediately before and 1, 2, 4, 6, 8, 10 and 12 hours after a morning lopinavir/ritonavir dose. Lopinavir and ritonavir concentrations in plasma were determined by high-performance liquid chromatography. First, a population pharmacokinetic model was developed for lopinavir and for ritonavir separately. The pharmacokinetic parameters, interindividual variability and residual error were estimated, and the influence of different patient characteristics on the pharmacokinetics of lopinavir and ritonavir was explored. Then, a simultaneous model estimating the pharmacokinetics of both drugs together and incorporating the influence of ritonavir exposure on oral clearance (CL/F) of lopinavir was developed. Population analysis was performed using nonlinear mixed-effects modelling (NONMEM version V software). The bias and precision of the final model were assessed through Monte Carlo simulations and data-splitting techniques. Results: A total of 53 and 25 Caucasian patients were included in two datasets for model building and model validation, respectively. Lopinavir and ritonavir pharmacokinetics were described by one-compartment models with first-order absorption and elimination. The presence of advanced liver fibrosis decreased CL/F of ritonavir by nearly half. The volume of distribution after oral administration (Vd/F) and CL/F of lopinavir were reduced as α1-acid glycoprotein (AAG) concentrations increased. CL/F of lopinavir was inhibited by ritonavir concentrations following a maximum-effect model (maximum inhibition [Imax] = 1, concentration producing 50% of the Imax [IC50] = 0.36 mg/L). The final model appropriately predicted plasma concentrations in the model-validation dataset with no systematic bias and adequate precision. Conclusion: A population model to simultaneously describe the pharmacokinetics of lopinavir and ritonavir was developed and validated in HIV-infected patients. Bayesian estimates of the individual parameters of ritonavir and lopinavir could be useful to predict lopinavir exposure based on the presence of advanced liver fibrosis and the AAG concentration in an individual manner, with the aim of maximizing the chances of treatment success.

Lopinavir/ritonavir pharmacokinetics in HIV and hepatitis C virus co-infected patients without liver function impairment : Influence of liver fibrosis

AbstractBackground and objective: To assess the influence of hepatitis C virus (HCV) co-infection and the extent of liver fibrosis on lopinavir/ritonavir pharmacokinetics in HIV-infected patients without liver function impairment. Methods: Cross-sectional, comparative study enrolling HIV-infected adults receiving lopinavir/ritonavir (400mg/100mg twice daily). HIV/HCV co-infected patients were grouped as having advanced fibrosis (HCV+/FIB+, n = 7) or not (HCV+/FIB−, n = 8) based on the FIB-4 index. A full concentration-time profile was obtained for each patient, and blood samples were collected before (0), and 1, 2, 4, 6, 8, 10 and 12 hours after a lopinavir/ritonavir dose. Lopinavir and ritonavir concentrations in plasma were determined by high-performance liquid chromatography. Maximum and minimum plasma concentrations (Cmax and Cmin), area under the plasma concentration-time curve from 0 to 12 hours (AUC12), apparent oral clearance at steady state (CLss/F), and apparent volume of distribution after oral administration (Vd/F) were calculated for each individual using a non-compartmental approach. Results: Twenty-six HCV− and 22 HCV+ patients were enrolled. Lopinavir and ritonavir pharmacokinetics were comparable between HCV− and HCV+ patients. However, the Vd/F of lopinavir was 125% higher in HCV+/FIB+ patients than in HCV− patients (p = 0.015) and 107% higher than in HCV+/FIB− (p = 0.040) patients. The CLss/F of ritonavir was 40% lower in HCV+/FIB+ patients than in HCV− patients (p = 0.005) and 44% lower than in HCV+/FIB− patients (p = 0.040). Thus, for ritonavir AUC12, Cmax and Cmin in HCV+/FIB+ patients were 63%, 86% and 100% higher, respectively, when compared with those parameters in HCV− patients (p = 0.005, p = 0.012 and p = 0.015, respectively), and 80%, 86% and 100% higher, respectively, when compared with levels in HCV+/FIB−patients (p = 0.040, p = 0.040 and p = 0.029, respectively). Conclusion: Lopinavir exposure is similar in HIV-infected patients with or without HCV co-infection and without liver function impairment. However, ritonavir exposure may be higher in this setting, particularly in individuals with advanced liver fibrosis.

Religious tourism and sacred places in Spain: old practices, new forms of tourism

Heritage, images, shrines, beliefs and devotions are related to culture, identity, religious feeling and faith, but also to the consumption of a tourism product. Religious tourism is an important type of cultural tourism that is now firmly established within the range of tourism products available in Spain. The article aims to demonstrate that religious tourism and cultural tourism form a joint trend that is an expression of the commercialisation of culture or, more exactly, of religion and popular devotion. Based on this hypothesis, the authors examine the cases of Montserrat monastery, the Road to Santiago and Holy Week in Granada that have in common a link between religious heritage and tourism. They emerge as examples of cultural and religious expression that have become multi-motivated tourism products, albeit with a significant religious base.