A randomized phase 1 study of safety, tolerability, and pharmacokinetics of MK-1088, a novel dual adenosine receptor antagonist, in healthy adult participants.

This phase 1 first-in-human study evaluated the safety, tolerability, and pharmacokinetics of MK-1088, a novel, small-molecule dual inhibitor of adenosine A and A receptors. Healthy adult participants were enrolled in two panels (n = 8 each) and randomly assigned to receive MK-1088 (n = 6) or placebo (n = 2) orally in each of five treatment periods. Participants in panel A received single ascending doses of MK-1088 at 1, 10, 50, and 150 mg or placebo in a fasted or fed (50 mg only) state.

Fine-Needle Aspiration for the Evaluation of Hepatic Pharmacokinetics of Vaniprevir: A Randomized Trial in Patients With Hepatitis C Virus Infection.

Fine-needle aspiration (FNA) for serial hepatic sampling may be an efficient and less invasive alternative to core needle biopsy (CNB), the current standard for liver tissue sampling. In this randomized, open-label trial in 31 participants with hepatitis C virus genotype 1 infection (NCT01678131/Merck protocol PN048), we evaluated the feasibility of using FNA to obtain human liver tissue samples appropriate for measuring hepatic pharmacokinetics (PK), using vaniprevir as a tool compound. The primary end point was successful retrieval of liver tissue specimens with measurable vaniprevir concentrations at two of three specified FNA time points.

Antiviral Activity, Safety, and Tolerability of Multiple Ascending Doses of Elbasvir or Grazoprevir in Participants Infected With Hepatitis C Virus Genotype-1 or -3.

Purpose: Elbasvir (MK-8742) and grazoprevir (MK-5172; Merck & Co, Inc, Kenilworth, New Jersey) are hepatitis C virus (HCV)-specific inhibitors of the nonstructural protein 5A phosphoprotein and the nonstructural protein 3/4A protease, respectively. The aims of these studies were to evaluate the antiviral activity and safety of different doses of elbasvir or grazoprevir each administered as monotherapy to participants infected with either HCV genotype (GT) 1 or GT3.

Methods: These 2 double-blind, randomized, placebo-controlled, sequential-panel, multiple ascending dose studies were conducted to assess the safety and pharmacodynamics of 5 days of once-daily elbasvir or 7 days of once-daily grazoprevir in adult male participants chronically infected with either HCV GT1 or GT3.

Kinetics of TH2 biomarkers in sputum of asthmatics following inhaled allergen.

Background: Allergen-induced late airway response offers important pharmacodynamic targets, including T helper 2 (TH2) biomarkers. However, detection of inflammatory markers has been limited in dithiothreitol-processed sputum.

Objectives: To test whether allergen-induced TH2 inflammatory markers can be reproducibly quantified by sensitive detection techniques in ultracentrifuged sputum and the effect of fluticasone (FP) on these endpoints.

Characterizing the PK/PD relationship for inhibition of capsaicin-induced dermal vasodilatation by MK-3207, an oral calcitonin gene related peptide receptor antagonist.

Aims: Calcitonin gene related peptide (CGRP) receptor antagonists are effective acute migraine treatments. A capsaicin-induced dermal vasodilatation (CIDV) model has been developed to provide target-engagement information in healthy volunteers. In the model, CGRP release is provoked after dermal capsaicin application, by activating transient receptor potential vanilloid-type-1 (TRPV1) receptors at peripheral sensory nerves.

Placebo- and amitriptyline-controlled evaluation of central nervous system effects of the NK1 receptor antagonist aprepitant and intravenous alcohol infusion at pseudo-steady state.

Recent interest in NK1 receptor antagonists has focused on a potential role in the treatment of drug addiction and substance abuse. In the present study, the potential for interactions between the NK1 receptor antagonist aprepitant and alcohol, given as an infusion at a target level of 0.65 g/L, was evaluated.

A comparison of the natriuretic and kaliuretic effects of cicletanine and hydrochlorothiazide in prehypertensive and hypertensive humans.

Objectives: The aim of this study was to compare the single-dose effects of thiazide-type diuretics cicletanine and hydrochlorothiazide (HCTZ), on natriuresis and kaliuresis in prehypertensive and treatment-naïve, stage 1 hypertensive patients and to explore the impact of GRK4 gene polymorphisms on thiazide-induced urinary electrolyte excretion.

Methods: The study was a randomized, double-blind, placebo-controlled, three-period, four-treatment, balanced incomplete block, cross-over study in male patients assigned to treatment sequences consisting of placebo, cicletanine 50 mg, cicletanine 150 mg, and HCTZ 25 mg, doses used to treat hypertension. Cumulative urine samples were collected predosing and over 24 h after dosing in each period to compare urine electrolyte excretion profiles of potassium (UKV), sodium (UNaV), magnesium, calcium, phosphate, chloride, and pH among groups.

Prednisone affects inflammation, glucose tolerance, and bone turnover within hours of treatment in healthy individuals.

Objective: Use of glucocorticoids for anti-inflammatory efficacy is limited by their side effects. This study examined, in the same individuals, prednisone's acute, dose-dependent effects on inflammation as well as biomarkers of glucose regulation and bone homeostasis.

Design: In this randomized, double-blind, parallel-design trial of healthy adults demonstrating cutaneous allergen-induced hypersensitivity, patients received placebo or prednisone 10, 25 or 60 mg daily for 7 days.

A randomized clinical trial comparing point-of-care platelet function assays and bleeding time in healthy subjects treated with aspirin or clopidogrel.

Traditional assays of the coagulation status of patients, bleeding time assessment (BT) and light transmission aggregometry (LTA), are useful in clinical drug development. However, these assays are both labor intensive and expensive. BT results can be operator dependent and by its nature can inhibit subject enrollment in a clinical trial.

A single supratherapeutic dose of vorinostat does not prolong the QTc interval in patients with advanced cancer.

Purpose: This dedicated QTc phase I study, conducted in advanced-stage cancer patients, assessed the effect of a single supratherapeutic dose (800 mg) of vorinostat on the QTc interval.

Experimental Design: A randomized, partially blind, placebo-controlled, two-period, crossover study was conducted. Patients (n = 25) received single doses of 800 mg vorinostat and placebo in the fasted state.

Single-dose pharmacokinetics and pharmacodynamics of anacetrapib, a potent cholesteryl ester transfer protein (CETP) inhibitor, in healthy subjects.

Aims: Anacetrapib 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.

Methods: Safety, tolerability, anacetrapib concentrations and CETP activity were evaluated.

Multiple-dose pharmacokinetics, pharmacodynamics, and safety of taranabant, a novel selective cannabinoid-1 receptor inverse agonist, in healthy male volunteers.

Taranabant is a cannabinoid-1 receptor inverse agonist for the treatment of obesity. This study evaluated the safety, pharmacokinetics, and pharmacodynamics of taranabant (5, 7.5, 10, or 25 mg once daily for 14 days) in 60 healthy male subjects.

Aprepitant when added to a standard antiemetic regimen consisting of ondansetron and dexamethasone does not affect vinorelbine pharmacokinetics in cancer patients.

Purpose: Aprepitant, a selective neurokinin-1 (NK-1) receptor antagonist approved for the treatment and prevention of emesis caused by moderately and highly emetogenic chemotherapy, is an inhibitor, inducer, and substrate of the cytochrome P450 3194 pathway. The CYP3A4 pathway is the major pathway of the metabolism of vinorelbine, a vinca alkaloid frequently used in combination with cisplatin. Therefore, we studied the potential interaction of the aprepitant 3-day antiemetic regimen on the pharmacokinetics of vinorelbine.

Effect of single oral doses of sitagliptin, a dipeptidyl peptidase-4 inhibitor, on incretin and plasma glucose levels after an oral glucose tolerance test in patients with type 2 diabetes.

Context: In response to a meal, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) are released and modulate glycemic control. Normally these incretins are rapidly degraded by dipeptidyl peptidase-4 (DPP-4). DPP-4 inhibitors are a novel class of oral antihyperglycemic agents in development for the treatment of type 2 diabetes.

Pharmacokinetics and pharmacodynamics of sitagliptin, an inhibitor of dipeptidyl peptidase IV, in healthy subjects: results from two randomized, double-blind, placebo-controlled studies with single oral doses.

Background: Sitagliptin (MK-0431 [(2R)-4-oxo-4-(3-[trifluoromethyl]-5,6-dihydro[1,2,4]triazolo[4,3-a]pyrazin-7[8H]-yl)-1-(2,4,5-trifluorophenyl)butan-2-amine]) is an orally active, potent, and selective inhibitor of dipeptidyl peptidase IV (DPP-IV) currently in phase III development for the treatment of type 2 diabetes.

Methods: Two double-blind, randomized, placebo-controlled, alternating-panel studies evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics of single oral doses of sitagliptin (1.5-600 mg) in healthy male volunteers.

Lack of effect of aprepitant on the pharmacokinetics of docetaxel in cancer patients.

Background: Aprepitant is a selective neurokinin-1 receptor antagonist that is effective for the prevention of nausea and vomiting caused by highly emetogenic chemotherapy. In vitro, aprepitant is a moderate inhibitor of the CYP3A4 enzyme, which is involved in the clearance of several chemotherapeutic agents. In this study we examined the potential for aprepitant to affect the pharmacokinetics and toxicity of intravenously administered docetaxel, a chemotherapeutic agent that is primarily metabolized by CYP3A4.