Platelet aggregation unchanged by lipoprotein-associated phospholipase A₂ inhibition: results from an in vitro study and two randomized phase I trials.

Background: We explored the theorized upregulation of platelet-activating factor (PAF)- mediated biologic responses following lipoprotein-associated phospholipase A2 (Lp-PLA2) inhibition using human platelet aggregation studies in an in vitro experiment and in 2 clinical trials.

Methods And Results: Full platelet aggregation concentration response curves were generated in vitro to several platelet agonists in human plasma samples pretreated with rilapladib (selective Lp-PLA2 inhibitor) or vehicle. This was followed by a randomized, double-blind crossover study in healthy adult men (n = 26) employing a single-agonist dose assay of platelet aggregation, after treatment of subjects with 250 mg oral rilapladib or placebo once daily for 14 days.

Operating characteristics of a partial-block randomized crossover bioequivalence study for dutasteride, a drug with a long half-life: investigation through simulation and comparison with final results.

Studies to establish bioequivalence (BE) of a drug are important elements in support of drug applications. A typical BE study is conducted as a single dose, randomized, 2-period crossover design. For drugs with long half lives (≥ 48 hours) and evaluation of multiple BE objectives in 1 trial, this design may not be adequate.

Ethanol does not alter the pharmacokinetic profile of the controlled-release formulation of carvedilol.

The concomitant ingestion of alcohol may alter the release of a drug from a modified-release dosage form, posing a potential risk to patients. In a randomized, open-label, 4-period cross-over study, the pharmacokinetic profiles of R(+) and S(-) carvedilol were compared after a single oral dose of carvedilol controlled-release formulation (administered following a standard meal) was given alone or concomitantly with ethanol. Thirty-nine healthy subjects participated in this study.

Pharmacokinetic profile of controlled-release carvedilol in patients with left ventricular dysfunction associated with chronic heart failure or after myocardial infarction.

We compared the pharmacokinetic (PK) profiles of repeated dosing with the currently available immediate-release (IR) carvedilol (given twice daily) and a newly developed controlled-release (CR) formulation (given once daily) in patients with left ventricular dysfunction (LVD). We enrolled 188 patients with stable mild, moderate, or severe heart failure as well as survivors of a recent acute myocardial infarction (MI) with asymptomatic LVD (left ventricular ejection fraction View Article and Find Full Text PDF

Development of a pharmacokinetic/pharmacodynamic model for carvedilol to predict beta1-blockade in patients with congestive heart failure.

To determine whether the controlled-release (CR) formulation of carvedilol given once daily provides 24-hour beta1-receptor blockade similar to the currently marketed immediate-release (IR) formulation given twice daily, changes in exercise-induced heart rate after bicycle ergometry were measured. The pharmacokinetic (PK)/pharmacodynamic (PD) relation between S(-)-carvedilol concentration-the enantiomer with beta-blocking activity-and change in exercise-induced heart rate was defined in healthy subjects and was best described using a direct effect inhibitory E(max) model (with E(max) being the maximum effect). The population estimates for E(max) and concentration at 50% of the maximum effect (EC50) were 19.

Pharmacokinetic and pharmacodynamic comparison of controlled-release carvedilol and immediate-release carvedilol at steady state in patients with hypertension.

Carvedilol is indicated for the treatment of essential hypertension and mild-to-severe chronic heart failure, as well as the reduction of cardiovascular mortality in clinically stable post-myocardial infarction patients with left ventricular dysfunction. Carvedilol is a racemic mixture of R(+) and S(-) enantiomers that combines beta(1)-, beta(2)-, and alpha(1)-adrenoceptor blockade. For all indications, the immediate-release (IR) formulation of carvedilol is taken twice daily.

Pharmacokinetic properties of a new controlled-release formulation of carvedilol.

This review summarizes the pharmacokinetics (PK) of carvedilol after administration of a new once-daily controlled-release (CR) formulation. The plasma concentration-time profiles for both R(+)- and S(-)-carvedilol indicate that carvedilol CR will provide coverage over a 24-hour period similar to the current immediate-release (IR) twice-daily formulation. Exposures for both enantiomers, based on area under the curve (AUC), maximum plasma concentrations (C(max)), and trough concentrations, are equivalent for carvedilol CR compared with carvedilol IR.

Pharmacodynamics and pharmacokinetics of oral contraceptives co-administered with alosetron (Lotronex).

The 5-HT3 receptor antagonist alosetron (Lotronex) is indicated for use in women with severe, chronic, diarrhea-predominant irritable bowel syndrome (IBS) who have failed conventional therapy. Oral contraceptives (OCs) and alosetron are potential co-medications in women of childbearing age. This study assessed the effect of alosetron co-administration on pharmacodynamic markers of contraceptive efficacy, on the pharmacokinetics of estrogen and progesterone OC components, and on the activity of biochemical markers for the risk of thrombosis.

Fluticasone propionate aqueous nasal spray provided significantly greater improvement in daytime and nighttime nasal symptoms of seasonal allergic rhinitis compared with montelukast.

Background: The safety and efficacy of intranasal corticosteroids for the treatment of allergic rhinitis is well documented in the literature. Additionally, an expert panel has concluded that intranasal corticosteroids are the first line of therapy when obstruction is a major component of rhinitis. Montelukast is a leukotriene receptor antagonist recently approved for the treatment of seasonal allergic rhinitis (SAR).