In recent years, great emphasis has been placed on the role of arterial stiffness in the development of cardiovascular diseases. Indeed, the assessment of arterial stiffness is increasingly used in the clinical assessment of patients. Although several papers have previously addressed the methodological issues concerning the various indices of arterial stiffness currently available, and their clinical applications, clinicians and researchers still report difficulties in selecting the most appropriate methodology for their specific use. This paper summarizes the proceedings of several meetings of the European Network for Non-invasive Investigation of Large Arteries and is aimed at providing an updated and practical overview of the most relevant methodological aspects and clinical applications in this area.

While risk scores are invaluable tools for adapted preventive strategies, a significant gap exists between predicted and actual event rates. Additional tools to further stratify the risk of patients at an individual level are biomarkers. A surrogate endpoint is a biomarker that is intended as a substitute for a clinical endpoint. In order to be considered as a surrogate endpoint of cardiovascular events, a biomarker should satisfy several criteria, such as proof of concept, prospective validation, incremental value, clinical utility, clinical outcomes, cost-effectiveness, ease of use, methodological consensus, and reference values. We scrutinized the role of peripheral (i.e. not related to coronary circulation) noninvasive vascular biomarkers for primary and secondary cardiovascular disease prevention. Most of the biomarkers examined fit within the concept of early vascular aging. Biomarkers that fulfill most of the criteria and, therefore, are close to being considered a clinical surrogate endpoint are carotid ultrasonography, ankle-brachial index and carotid-femoral pulse wave velocity; biomarkers that fulfill some, but not all of the criteria are brachial ankle pulse wave velocity, central haemodynamics/wave reflections and C-reactive protein; biomarkers that do no not at present fulfill essential criteria are flow-mediated dilation, endothelial peripheral arterial tonometry, oxidized LDL and dysfunctional HDL. Nevertheless, it is still unclear whether a specific vascular biomarker is overly superior. A prospective study in which all vascular biomarkers are measured is still lacking. In selected cases, the combined assessment of more than one biomarker may be required.

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Vaginal delivery of 200 mg or 25 mg dapivirine from intravaginal rings (IVRs) was evaluated over a 7-day period in two phase 1 safety trials (IPM001 and IPM008, respectively) in a total of 25 healthy women 19 to 46 years of age. The IVR was generally safe and well tolerated with similar adverse events observed in the placebo and dapivirine groups. Across both studies, dapivirine concentrations in vaginal fluids measured at the introitus, cervix, and ring area were within the mean range of 0.7-7.1 microg/ml. Mean dapivirine concentrations in vaginal and cervical tissues on day 7 were 0.3-0.7 microg/g in IPM001 and 1.5-3.5 microg/g in IPM008. Mean plasma concentrations of dapivirine were <50 pg/ml. Dapivirine from both IVRs was successfully distributed throughout the lower genital tract at concentrations >1000x the EC(50) against wild-type HIV-1 (LAI) in MT4 cells suggesting that IVR delivery of microbicides is a viable option meriting further study.

Doravirine is generally well tolerated in single doses up to 1,200 mg and multiple doses up to 750 mg once daily for up to 10 days, with a pharmacokinetic profile supportive of once-daily dosing. Doravirine at steady state slightly reduced the exposure of coadministered midazolam, to a clinically unimportant extent.

Background Carotid-femoral pulse wave velocity (CFPWV) is a heritable measure of aortic stiffness that is strongly associated with increased risk for major cardiovascular disease events. Methods and Results We conducted a meta-analysis of genome-wide association data in 9 community-based European ancestry cohorts consisting of 20,634 participants. Results were replicated in 2 additional European ancestry cohorts involving 5,306 participants. Based on a preliminary analysis of 6 cohorts, we identified a locus on chromosome 14 in the 3′-BCL11B gene desert that is associated with CFPWV (rs7152623, minor allele frequency = 0.42, beta=−0.075±0.012 SD/allele, P = 2.8 x 10−10; replication beta=−0.086±0.020 SD/allele, P = 1.4 x 10−6). Combined results for rs7152623 from 11 cohorts gave beta=−0.076±0.010 SD/allele, P=3.1x10−15. The association persisted when adjusted for mean arterial pressure (beta=−0.060±0.009 SD/allele, P = 1.0 x 10−11). Results were consistent in younger (<55 years, 6 cohorts, N=13,914, beta=−0.081±0.014 SD/allele, P = 2.3 x 10−9) and older (9 cohorts, N=12,026, beta=−0.061±0.014 SD/allele, P=9.4x10−6) participants. In separate meta-analyses, the locus was associated with increased risk for coronary artery disease (hazard ratio [HR]=1.05, confidence interval [CI]=1.02 to 1.08, P=0.0013) and heart failure (HR=1.10, CI=1.03 to 1.16, P=0.004). Conclusions Common genetic variation in a locus in the BCL11B gene desert that is thought to harbor one or more gene enhancers is associated with higher CFPWV and increased risk for cardiovascular disease. Elucidation of the role this novel locus plays in aortic stiffness may facilitate development of therapeutic interventions that limit aortic stiffening and related cardiovascular disease events.

Data regarding ethnic differences in wave reflections, which markedly affect the central pressure profile, are very limited. Furthermore, because age, heart rate and body height are strong determinants of augmentation index, relating single measurements to normative data (in which augmentation index values correspond to average population values of its determinants) is challenging. We studied subject-level data from 10,550 adults enrolled in large population-based studies. In a healthy reference sample (n=3,497), we assessed ethnic differences in augmentation index (ratio of second/first systolic peaks) and generated equations for adjusted z-scores, allowing for a standardized comparison between individual augmentation index measurements and the normative population mean from subjects of the same age, gender, ethnic population, body height and heart rate. After adjustment for age, body height, heart rate and mean arterial pressure, African blacks (women:154%; men:138%) and Andean-Hispanics (women:152%; men:133%) demonstrated higher central (aortic) augmentation index values than British whites (women:140%; men:128%); whereas American Indians (women:133%; men:122%) demonstrated lower augmentation index (all P<0.0001), without significant differences between Chinese and British whites. Similar results were found for radial augmentation index. Non-linear ethnic/gender-specific equations for z-scores were successfully generated to adjust individual augmentation index values for age, body height and heart rate. Marked ethnic differences in augmentation index exist, which may contribute to ethnic differences in hypertensive organ damage. Our study provides normative data that can be used to complement the interpretation of individual hemodynamic assessments among men and women of various ethnic populations, after removing the effect of various physiologic determinants.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT• Inhibition of cholesteryl ester transfer protein (CETP) is considered a potential new mechanism for the treatment of dyslipidaemia. Whereas several studies have described the effects of the CETP inhibitors, torcetrapib (Pfizer) and dalcetrapib (Roche), on lipids and lipoproteins, few studies have characterized the effect of rising single doses on the pharmacokinetics and pharmacodynamics (CETP activity) of an individual CETP inhibitor or have described the effects of intrinsic and extrinsic factors on the pharmacokinetics and pharmacodynamics of these agents. WHAT THIS STUDY ADDS• We have characterized the exposure/response relationship for the inhibition of CETP activity over a wide exposure range. We have shown that single doses of anacetrapib produced marked and dose-dependent inhibition of serum CETP activity with peak effects of 90% inhibition at tmax and persistent inhibition at 24 h post-dose. We have also shown that whereas food increased exposures to anacetrapib significantly and variably, age, gender and obese status did not meaningfully influence the pharmacokinetics and pharmacodynamics of anacetrapib. AIMSAnacetrapib is an orally active and potent inhibitor of CETP in development for the treatment of dyslipidaemia. These studies endeavoured to establish the safety, tolerability, pharmacokinetics and pharmacodynamics of rising single doses of anacetrapib, administered in fasted or fed conditions, and to preliminarily assess the effect of food, age, gender and obesity on the single-dose pharmacokinetics and pharmacodynamics of anacetrapib. METHODSSafety, tolerability, anacetrapib concentrations and CETP activity were evaluated. RESULTSAnacetrapib was rapidly absorbed, with peak concentrations occurring at~4 h post-dose and an apparent terminal half-life ranging from~9 to 62 h in the fasted state and from~42 to~83 h in the fed state. Plasma AUC and Cmax appeared to increase in a less than approximately dose-dependent manner in the fasted state, with an apparent plateau in absorption at higher doses. Single doses of anacetrapib markedly and dose-dependently inhibited serum CETP activity with peak effects of 90% inhibition at tmax and~58% inhibition at 24 h post-dose. An Emax model best described the plasma anacetrapib concentration vs CETP activity relationship with an EC50 of~22 nM. Food increased exposure to anacetrapib; up to~two-three-fold with a low-fat meal and by up to~six-eight fold with a high-fat meal. Anacetrapib pharmacokinetics and pharmacodynamics were similar in elderly vs young adults, women vs men, and obese vs non-obese young adults. Anacetrapib was well tolerated and was not associated with any meaningful increase in blood pressure. CONCLUSIONSWhereas food increased exposure to anacetrapib significantly, age, gender and obese status did not meaningfully influence anacetrapib pharmacokinetics and pharmacodynamics.