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Atherogenesis is the narrowing of arteries due to plaque build-up that results in cardiovascular disease that can lead to death. The macrophage lectin-like oxidized LDL receptor-1 (LOX-1), also called the oxidized low-density lipoprotein receptor 1 (OLR1), is currently thought to aid in atherosclerotic disease progression; therefore metabolic studies have potential to both provide mechanistic validation for the role of LOX-1 in disease progression and provide valuable information regarding biomarker strategies and clinical imaging. One such mechanistic study is the upregulation of LOX-1 by methylated bacterial DNA and deoxy-cytidylate-phosphate-deoxy-guanylate-DNA (CpG)-DNA exposure. CpG-DNA is known to promote oxidative burst responses in macrophages, due to its direct binding to toll-like receptor 9 (TLR9) leading to the initiation of an NF-κB mediated immune response. In addition to the upregulation of macrophage LOX-1 expression, these studies have also examined the macrophage metabolic response to murine LOX-1/OLR1 antibody exposure. Our data suggests the antibody exposure effectively blocks LOX-1 dependent oxLDL metabolic activation of the macrophage, which was quantified using the multianalyte microphysiometer (MAMP). Using the MAMP to examine metabolic fluctuations during various types of oxLDL exposure, LOX-1 upregulation and inhibition provide valuable information regarding the role of LOX-1 in macrophage activation of oxidative burst. [ABSTRACT FROM AUTHOR]

Single-pill combinations (SPCs) of complementary antihypertensive agents provide patients with a simple and effective treatment regimen. To ensure that the efficacy and safety of an SPC is the same as that for the individual drugs administered together (free combination), SPC and free-combination formulations must be shown to be bioequivalent. Three open-label, randomized studies compared the pharmacokinetics of SPC tablets of the direct renin inhibitor aliskiren and hydrochlorothiazide (HCT), at doses of 150/25, 300/12.5, and 300/25 mg, with the corresponding free combinations in healthy volunteers. Data from 2 randomized, double-blinded studies of patients with hypertension were used to assess inhibition of plasma renin activity (PRA) by the aliskiren/HCT 300/25 mg SPC and the free combination. At all dose combinations, aliskiren and HCT systemic drug exposure was similar when administered as an SPC or free combination, indicating bioequivalence. Aliskiren/HCT 300/25 mg SPC inhibited PRA to the same extent as the free combination. HCT alone increased PRA through activation of the renin-angiotensin system; aliskiren prevented this diuretic-induced increase to the same extent when administered as the free combination or as the SPC. In conclusion, aliskiren/HCT SPCs are pharmacokinetically and pharmacodynamically bioequivalent to aliskiren and HCT in free combination. [ABSTRACT FROM PUBLISHER]

Gender and body weight influence the pharmacokinetics and pharmacodynamics of many drugs. This pooled analysis of 17 clinical studies evaluated the effect of gender, body mass index (BMI), body weight, and lean body weight (LBW) on the pharmacokinetics of the direct renin inhibitor aliskiren in healthy volunteers (n = 392). A separate pooled analysis of 5 clinical studies in patients with hypertension (n = 2327) assessed the influence of gender and BMI on the effects of aliskiren on plasma renin activity and blood pressure. Area under the aliskiren plasma concentration—time curve (AUCτ) was 22% lower and the peak aliskiren plasma concentration (Cmax) was 24% lower in men than women (P < .05). BMI was not significantly correlated with AUCτ(r = 0.005; P = .917); AUC τwas negatively correlated with body weight (r = −0.235; P < .0001) and LBW (r = −0.295; P < .0001). Results were similar for Cmax. Adjusting individual aliskiren AUC τand Cmax values for overall mean body weight or LBW abolished gender differences. Based on r2 values, LBW variation accounted for 8.9% of aliskiren AUCτ variation. In patients with hypertension, gender and BMI did not significantly influence the effects of aliskiren on plasma renin activity or blood pressure. It was concluded that lower systemic exposure to aliskiren in men versus women relates to differences in body weight; neither gender nor body weight has clinically relevant effects on the pharmacokinetics or pharmacodynamics of aliskiren. [ABSTRACT FROM PUBLISHER]

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • Vildagliptin is an orally active, potent inhibitor of dipeptidyl peptidase IV and was developed for the treatment of type 2 diabetes. • In clinical trials, once or twice daily dosing with vildagliptin (up to 100 mg day−1) has been shown to reduce endogenous glucose production and fasting plasma glucose in patients with type 2 diabetes. • The comparative efficacy of vildagliptin under a morning vs. evening dosing regimen has not previously been determined. WHAT THIS STUDY ADDS • Once daily dosing with vildagliptin 100 mg for 28 days improved glycaemic control in patients with type 2 diabetes independent of whether vildagliptin was administered in the morning or evening. • Morning or evening dosing with vildagliptin had similar effects on 24 h glycaemic control and plasma concentrations of the hormones insulin, glucagon and glucagon-like peptide 1. AIM This randomized, double-blind, crossover study compared post-prandial hormonal and metabolic effects of vildagliptin, (an oral, potent, selective inhibitor of dipeptidyl peptidase IV [DPP-4]) administered morning or evening in patients with type 2 diabetes. METHODS Forty-eight patients were randomized to once daily vildagliptin 100 mg administered before breakfast or before dinner for 28 days then crossed over to the other dosing regimen. Blood was sampled frequently after each dose at baseline (day −1) and on days 28 and 56 to assess pharmacodynamic parameters. RESULTS Vildagliptin inhibited DPP-4 activity (>80% for 15.5 h post-dose), and increased active glucagon-like peptide-1 compared with placebo. Both regimens reduced total glucose exposure compared with placebo (area under the 0–24 h effect–time curve [AUE(0,24 h)]: morning −467 mg dl−1 h, P= 0.014; evening −574 mg dl−1 h, P= 0.003) with no difference between regimens ( P= 0.430). Reductions in daytime glucose exposure (AUE(0,10.5 h)) were similar between regimens. Reduction in night-time exposure (AUE(10.5,24 h) was greater with evening than morning dosing (−336 vs.−218 mg dl−1 h, P= 0.192). Only evening dosing significantly reduced fasting plasma glucose (−13 mg dl−1, P= 0.032) compared with placebo. Insulin exposure was greater with evening dosing (evening 407 µU ml−1 h; morning 354 µU ml−1 h, P= 0.050). CONCLUSIONS Both morning and evening dosing of once daily vildagliptin 100 mg significantly reduced post-prandial glucose in patients with type 2 diabetes; only evening dosing significantly decreased fasting plasma glucose. Although evening dosing with vildagliptin 100 mg tended to decrease night-time glucose exposure more than morning dosing, both regimens were equally effective in reducing 24 h mean glucose exposure (AUE(0,24 h)) in patients with type 2 diabetes. [ABSTRACT FROM AUTHOR]

Angiotensin receptor blockade and neprilysin (NEP) inhibition together offer potential benefits for the treatment of hypertension and heart failure. LCZ696 is a novel single molecule comprising molecular moieties of valsartan and NEP inhibitor prodrug AHU377 (1:1 ratio). Oral administration of LCZ696 caused dose-dependent increases in atrial natriuretic peptide immunoreactivity (due to NEP inhibition) in Sprague-Dawley rats and provided sustained, dose-dependent blood pressure reductions in hypertensive double-transgenic rats. In healthy participants, a randomized, double-blind, placebo-controlled study (n = 80) of single-dose (200-1200 mg) and multiple-dose (50-900 mg once daily for 14 days) oral administration of LCZ696 showed that peak plasma concentrations were reached rapidly for valsartan (1.6-4.9 hours), AHU377 (0.5-1.1 hours), and its active moiety, LBQ657 (1.8-3.5 hours). LCZ696 treatment was associated with increases in plasma cGMP , renin concentration and activity, and angiotensin II, providing evidence for NEP inhibition and angiotensin receptor blockade. In a randomized, open-label crossover study in healthy participants (n = 56), oral LCZ696 400 mg and valsartan 320 mg were shown to provide similar exposure to valsartan (geometric mean ratio [90% confidence interval]: AUC0-∞ 0.90 0-8 [0.82-0.99]). LCZ696 was safe and well tolerated. These data support further clinical development of LCZ696, a novel, orally bioavailable, dual-acting angiotensin receptor- NEP inhibitor (ARNi) for hypertension and heart failure. [ABSTRACT FROM AUTHOR]

Vildagliptin is an orally effective, potent, and selective inhibitor of dipeptidyl peptidase IV (DPP-4) that improves glycemic control in patients with type 2 diabetes. This was a randomized, double-blind, placebo-controlled, time-lagged, parallel-group study in a total of 60 healthy Chinese participants. Single- and multiple-dose pharmacokinetics and pharmacodynamics, and safety and tolerability of vildagliptin were assessed following administration of 25, 50, 100, or 200 mg qd, or 50 mg bid. Vildagliptin was rapidly absorbed (t[submax] 1.5-2.0 hours) across the dose range of 25 to 200 mg and was quickly eliminated with a terminal elimination half-life (t[sub1/2]) of approximately 2 hours. Consistent with the short t1/2, no accumulation of vildagliptin was observed following the administration of multiple doses (accumulation factors were 1.00-1.05 across the 25- to 200-mg dose range). Vildagliptin AUC and C[submax] values increased in an approximately dose-proportional fashion (dose proportionality constant β 1.00-1.16). Administration of vildagliptin 25 to 200 mg led to rapid and near-complete (>95%) inhibition of DPP-4 activity for at least 4 hours after dosing, which was associated with increases in plasma active glucagon-like peptide-1 of up to 2- to 3-fold compared with placebo. The duration of DPP-4 inhibition increased with dose. Glucose and insulin levels were not affected by vildagliptin in healthy participants, consistent with the fact that the glucose-lowering effects of vildagliptin occur in a glucose-dependent fashion. Vildagliptin was well tolerated at the highest tested dose of 200 mg qd. Vildagliptin 25 to 200 mg qd exhibits approximately dose-proportional pharmacokinetics with no evidence of accumulation after multiple dosing in healthy Chinese participants. Vildagliptin demonstrates potent inhibition of DPP-4 activity with excellent tolerability at doses of up to and including 200 mg qd. [ABSTRACT FROM AUTHOR]

This study investigated the pharmacokinetics, safety, and tolerability of aliskiren administered alone or in combination with either the loop diuretic furosemide or an oral extended-release formulation of isosorbide-5-mononitrate (ISMN). In separate studies, 22 healthy subjects (ages 18–45 years) received either ISMN 40 mg or furosemide 20 mg once-daily for 3 days followed by a 3-day washout. Subjects then received aliskiren 300 mg once-daily for 7 days followed by combination therapy for 3 days. Pharmacokinetic assessments were taken at regular intervals over 24 h after dosing on the last day of each treatment period. At steady state, aliskiren AUCτ was decreased by 7% (geometric mean ratio [90% CI], 0.93 [0.84, 1.04]), and Cmax by 20% (0.80 [0.65, 0.97]) with furosemide coadministration compared with aliskiren administration alone. Aliskiren coadministration reduced furosemide AUCτ by 28% (0.72 [0.64, 0.81]) and Cmax by 49% (0.51 [0.39, 0.66]) compared with furosemide alone. Coadministration of aliskiren and ISMN was associated with only minor changes in the pharmacokinetic parameters of aliskiren (AUCτ 1.03 [0.90, 1.18]; Cmax 0.94 [0.69, 1.29]) and ISMN (AUCτ 0.88 [0.71, 1.10]; Cmax 0.94 [0.79, 1.13]). Headache and dizziness were the most common adverse events in both studies; dizziness and BP values below normal (SBP <90 and/or DBP <50 mmHg) were more frequent with aliskiren and ISMN coadministration than with either agent alone. Coadministration of aliskiren and ISMN had no clinically relevant effect on either aliskiren or ISMN pharmacokinetics. In conclusion, coadministration of aliskiren and furosemide reduced furosemide exposure and had a minor effect on aliskiren pharmacokinetics. The clinical significance of reduced systemic exposure to furosemide during coadministration of aliskiren is uncertain. [ABSTRACT FROM AUTHOR]

This study investigated the potential pharmacokinetic interaction between the direct renin inhibitor aliskiren and modulators of P-glycoprotein and cytochrome P450 3A4 (CYP3A4). Aliskiren stimulated in vitro P-glycoprotein ATPase activity in recombinant baculovirus-infected Sf9 cells with high affinity (Km 2.1 μmol/L) and was transported by organic anion-transporting peptide OATP2B1-expressing HEK293 cells with moderate affinity (Km 72 μmol/L). Three open-label, multiple-dose studies in healthy subjects investigated the pharmacokinetic interactions between aliskiren 300 mg and digoxin 0.25 mg (n = 22), atorvastatin 80 mg (n = 21), or ketoconazole 200 mg bid (n = 21). Coadministration with aliskiren resulted in changes of <30% in AUC and Cmax,ss of digoxin, atorvastatin, o-hydroxy-atorvastatin, and -hydroxy-atorvastatin, indicating no clinically significant interaction with P-glycoprotein or CYP3A4 substrates. Aliskiren AUC was significantly increased by coadministration with atorvastatin (by 47%, P < .001) or ketoconazole (by 76%, P < .001) through mechanisms most likely involving transporters such as P-glycoprotein and organic anion-transporting peptide and possibly through metabolic pathways such as CYP3A4 in the gut wall. These results indicate that aliskiren is a substrate for but not an inhibitor of P-glycoprotein. On the basis of the small changes in exposure to digoxin and atorvastatin and the <2-fold increase in exposure to aliskiren during coadministration with atorvastatin and ketoconazole, the authors conclude that the potential for clinically relevant drug interactions between aliskiren and these substrates and/or inhibitors of P-glycoprotein/CPY3A4/OATP is low. [ABSTRACT FROM AUTHOR]

This multicenter, double-blind study evaluated the effects of aliskiren, a direct renin inhibitor approved for hypertension, on cardiac repolarization and conduction. Healthy volunteers (n = 298) were randomized to aliskiren 300 mg, aliskiren 1200 mg, moxifloxacin 400 mg (positive control), or placebo once daily for 7 days. Digitized electrocardiograms were obtained at baseline and day 7 of treatment over 23 hours postdose. Placebo-adjusted mean changes from baseline in QTcF (Fridericia corrected), QTcI (individualized correction), PR, and QRS intervals were compared at each time point (time-matched analysis) and for values averaged across the dosing period (baseline-averaged analysis). In time-matched analysis, mean changes in QTcF with aliskiren were below predefined limits for QTc prolongation (mean increase <5 milliseconds; upper 90% confidence interval [CI] <10 milliseconds) except aliskiren 1200 mg at 23 hours (5.2 milliseconds; 90%. CI 2.2, 8.1). With moxifloxacin significant QTcF prolongation occurred at most time points, confirming the sensitivity of the assay. Baseline-averaged analysis was consistent with time-matched analysis. Instances of QTcF interval >450 milliseconds or a >30-millisecond increase from baseline with aliskiren (≤1 %) were similar or lower than placebo (≤4 %). Results were similar for QTcI. Aliskiren had no effect on PR or QRS duration. In conclusion, aliskiren at the highest approved dose (300 mg) and a 4-fold higher dose had no effect on cardiac repolarization or conduction in healthy volunteers. [ABSTRACT FROM AUTHOR]

What is already known about this subject • Vildagliptin is a new, potent, and selective inhibitor of DPP-4. • The efficacy and safety of vildagliptin in type 2 diabetes has been intensively studied in diverse subject populations. • There has been little information published about the pharmacokinetics and pharmacodynamics of vildagliptin. What this study adds • No clinically relevant changes in pharmacokinetics or pharmacodynamics were observed between young and elderly, male and female, or high body mass index (BMI) and low BMI subjects. • The results suggest that no dose modification is necessary for vildagliptin based on the age, gender, or BMI of a subject. Aims To evaluate the effect of age, gender, and body mass index (BMI) on the pharmacokinetics and pharmacodynamics of vildagliptin. Methods Forty healthy subjects received a single oral dose of 100 mg vildagliptin to assess the effects of age, gender, and BMI on the pharmacokinetics and pharmacodynamics, reflected by the time course of inhibition of DPP-4 activity, of vildagliptin. Results Peak concentration and exposure (AUC(0–∞)) of vildagliptin were 17% (90% CI 2, 35%) and 31% (90% CI 18, 45%) higher in elderly vs. young subjects. Renal clearance was reduced by 32% (90% CI 17, 45%) in elderly subjects. The pharmacokinetics of vildagliptin were not significantly influenced by gender or BMI. Inhibition of DPP-4 activity was similar regardless of age, gender, or BMI. Conclusions The pharmacokinetics of a single oral 100 mg dose of vildagliptin were not affected by gender and BMI. Exposure to vildagliptin was higher in elderly patients, but this was not associated with any difference in the effect of DPP-4 inhibition. Based on these results, no vildagliptin dose adjustment is necessary for age, gender, or BMI. [ABSTRACT FROM AUTHOR]

Vildagliptin is a potent and selective dipeptidyl peptidase IV inhibitor in development for the treatment of type 2 diabetes that improves glycemic control by enhancing α- and β-cell responsiveness to glucose. Two open-label, single-dose, randomized, crossover studies in healthy subjects (ages 18-45 years) investigated the dose proportionality of vildagliptin pharmacokinetics (n = 20) and the effect of food (n = 24) on vildagliptin pharmacokinetics. There was a linear relationship (r² = 0.999) between vildagliptin doses of 25, 50, 100, and 200 mg and area under the plasma concentration-time curve from time zero to infinity (AUC0-∞) and maximum plasma concentration (Cmax). Dose proportionality was assessed using a statistical power model [X = α·(dose)β]. The 90% confidence intervals of the proportionality coefficient, β, for A UC0-∞, (1.15-1.19) and Cmax (1.04-1.1 4) indicated that deviations from dose proportionality were small (<7.7%). Doubling of dose led to 2.1- to 2.3-fold increases in AUC0-∞ and Cmax but no dose-dependent changes in time to reach Cmax or terminal elimination half-life. Administration of vildagliptin 100 mg following a high-fat meal decreased Cmax by 19% and AUC0-∞ by 10%. Vildagliptin displays approximately dose-proportional pharmacokinetics over the 25- to 200-mg dose range, and administration with food has no clinically relevant effect on vildagliptin pharmacokinetics. [ABSTRACT FROM AUTHOR]