Edoxaban Versus Warfarin in Patients With Atrial Fibrillation and History of Liver Disease.

Background: Patients with liver disease have increased risk of thrombosis and bleeding but are typically excluded from trials of direct oral anticoagulant agents.

Objectives: This study evaluated the pharmacokinetics (PK), pharmacodynamics (PD), clinical efficacy and safety of edoxaban versus warfarin in patients with atrial fibrillation (AF) and history of liver disease.

Methods: ENGAGE AF-TIMI 48 (Effective Anticoagulation With Factor Xa Next Generation in Atrial Fibrillation-Thrombolysis In Myocardial Infarction Study 48) was a randomized, double-blind trial comparing edoxaban with warfarin in patients with AF followed for 2.

Linking Endogenous Factor Xa Activity, a Biologically Relevant Pharmacodynamic Marker, to Edoxaban Plasma Concentrations and Clinical Outcomes in the ENGAGE AF-TIMI 48 Trial.

Background: We previously reported exogenous antifactor Xa (FXa) activity as a pharmacokinetic surrogate marker for edoxaban plasma concentrations. Inhibition of endogenous FXa activity is a more biologically relevant pharmacodynamic measure of edoxaban activity. Here we describe the value of endogenous FXa activity as a pharmacodynamic marker linking edoxaban concentrations and clinical outcomes in the ENGAGE AF-TIMI 48 trial (Effective Anticoagulation With Factor Xa Next Generation in Atrial Fibrillation-Thrombolysis in Myocardial Infarction Study 48).

Uninterrupted administration of edoxaban vs vitamin K antagonists in patients undergoing atrial fibrillation catheter ablation: Rationale and design of the ELIMINATE-AF study.

Patients with atrial fibrillation (AF) are at an approximately 0.5% to 3% increased risk of thromboembolism during and immediately after catheter ablation. Treatment guidelines recommend periprocedural oral anticoagulation plus unfractionated heparin during ablation.

Associations of the CYP3A5*3 and CYP3A4*1G polymorphisms with the pharmacokinetics of oral midazolam and the urinary 6β-hydroxycortisol/cortisol ratio as markers of CYP3A activity in healthy male Chinese.

What Is Known And Objective: The oral plasma clearance of midazolam and the ratio of 6β-hydroxycortisol (6β-OHF) to cortisol (F) in urine are two potential markers for evaluating CYP3A activity in vivo. We assessed the influence of two common CYP3A polymorphisms on the pharmacokinetics of oral midazolam and urinary ratio of 6β-OHF/F in healthy Chinese.

Methods: Single oral 15 mg doses of midazolam were given to 20 healthy male Chinese subjects who were genotyped for the CYP3A5*3 and CYP3A4*1G polymorphisms.

Edoxaban Exposure-Response Analysis and Clinical Utility Index Assessment in Patients With Symptomatic Deep-Vein Thrombosis or Pulmonary Embolism.

Edoxaban exposure-response relationships from the phase III study evaluating edoxaban for prevention and treatment of venous thromboembolism (VTE) in patients with acute deep vein thrombosis (DVT) and/or pulmonary embolism (PE) were assessed by parametric time-to-event analysis. Statistical significant exposure-response relationships were recurrent VTE with hazard ratio (HR) based on average edoxaban concentration at steady state (Cav) (HRCav) = 0.98 (i.

Population pharmacokinetic modeling and simulation for assessing renal impairment effect on the pharmacokinetics of mirogabalin.

A population pharmacokinetic model was developed to describe plasma concentrations of mirogabalin and lactam metabolite, obtained following a single oral dose of 5 mg mirogabalin to subjects with varying degrees of renal function.A 2-compartment model was used for both mirogabalin and lactam metabolite. Body weight was a significant covariate on volume of distribution of mirogabalin and lactam metabolite, whereas creatinine clearance significantly affected both renal and nonrenal clearance of mirogabalin.

Evaluating a physiologically based pharmacokinetic model for prediction of omeprazole clearance and assessing ethnic sensitivity in CYP2C19 metabolic pathway.

Purpose: The purpose of this study is to evaluate the ethnicity-specific population models in the SimCYP Simulator® for prediction of omeprazole clearance with attention to differences in the CYP2C19 metabolic pathway.

Methods: The SimCYP® models incorporating Caucasian, Chinese, and Japanese population-specific demographic, physiological, and enzyme data were applied to simulate omeprazole pharmacokinetics. Published pharmacokinetic data of omeprazole after intravenous or oral administration in Caucasian, Chinese, and Japanese were used for the evaluation.

Population pharmacokinetics and dose-exposure proportionality of edoxaban in healthy volunteers.

Background And Objectives: Edoxaban is a novel direct inhibitor of activated factor Xa. A previous human pharmacokinetic study suggested a less than proportional increase in edoxaban exposure at higher dose concentrations, but the quantitative relationship, including the point of inflection, has not yet been fully characterized. The objectives of this analysis were to characterize the population pharmacokinetics and quantify the dose-exposure relationship of edoxaban over a dose range of 10-180 mg.

Edoxaban population pharmacokinetics and exposure-response analysis in patients with non-valvular atrial fibrillation.

Purpose: The aim of this study was to evaluate the population pharmacokinetics (PK) and exposure-response relationship of edoxaban in patients with non-valvular atrial fibrillation (AF).

Methods: Concentration data from 1,134 subjects in 11 clinical studies (eight phase I, one phase II, and two phase III) were used to perform a population PK analysis, including estimation of the bioavailability and quantification of the effects of P-glycoprotein (P-gp) inhibitors as well as renal impairment on edoxaban PK. The potential relationship between edoxaban PK exposure and incidence of bleeding events was explored based on data from 893 AF patients.

CYP2C19 genotype has a major influence on labetalol pharmacokinetics in healthy male Chinese subjects.

Purpose: The pharmacokinetics (PK) of labetalol show wide inter-subject variability, but the genetic causes for this are largely undetermined. This study was performed to examine whether common polymorphisms in UGT1A1, UGT2B7, CYP2C19 and ABCB1 affect the PK of labetalol.

Methods: The PK of labetalol were determined in 37 Chinese healthy male subjects who took a single oral dose of 200 mg labetalol.

Effects of famotidine or an antacid preparation on the pharmacokinetics of nilotinib in healthy volunteers.

Purpose: This study evaluated the effects of either famotidine or antacid on the pharmacokinetics of nilotinib in healthy subjects, with the specific focus to explore different dosing separation schemes leading to a minimized drug-drug interaction.

Methods: Fifty-two subjects were randomized to receive the following treatments in a crossover manner: (A) single oral nilotinib 400 mg alone; (B) famotidine 20 mg twice a day for 3 days, followed by a single administration of nilotinib 400 mg and famotidine 20 mg on Day 4, where famotidine was given 2 h after nilotinib; (C) single oral nilotinib 400 mg and antacid suspension 20 mL, where antacid was given 2 h before nilotinib; (D) single oral nilotinib 400 mg and antacid suspension 20 mL, where antacid was given 2 h after nilotinib.

Results: Comparing Treatment B to Treatment A, the geometric mean ratios of nilotinib C(max), AUC(0-tlast), and AUC(0-inf) were 0.

Nilotinib population pharmacokinetics and exposure-response analysis in patients with imatinib-resistant or -intolerant chronic myeloid leukemia.

Purpose: We evaluated the population pharmacokinetics (PK) and exposure-response relationship of nilotinib in patients with imatinib-resistant or -intolerant chronic myeloid leukemia (CML).

Methods: Concentration data from 493 patients with CML in chronic phase (CML-CP), accelerated phase, or blast crisis were used to perform a population pharmacokinetic analysis using nonlinear mixed-effect modeling. Steady-state nilotinib trough concentrations (Cmin) in individual patients were estimated from the population PK model for correlation with the efficacy and safety variables.

Effects of grapefruit juice and SLCO1B1 388A>G polymorphism on the pharmacokinetics of pitavastatin.

Pitavastatin undergoes little hepatic metabolism but it is a substrate for uptake and efflux transporters, particularly OATP1B1 (gene SLCO1B1). A previous study in 8 Japanese healthy subjects showed that co-administration with grapefruit juice (GFJ) resulted in a small increase in systemic exposure to pitavastatin. We examined whether common polymorphisms in SLCO1B1 might influence the pharmacokinetics of pitavastatin or the interaction with GFJ.

Effects of CYP2D6*10, CYP3A5*3, CYP1A2*1F, and ABCB1 C3435T polymorphisms on the pharmacokinetics of flecainide in healthy Chinese subjects.

Background: Although flecainide is thought to be meta-bolized predominantly by cytochrome P450 (CYP) 2D6, it shows pharmacokinetic interactions with drugs, such as verapamil and digoxin, which may suggest other CYP pathways or ATP-binding cassette (ABC) transporters might be involved. This study evaluated effects of common polymorphisms in Chinese in CYP2D6, CYP3A5, CYP1A2, and ABCB1 on flecainide pharmacokinetics.

Methods: Single oral 100-mg doses of flecainide were given to 15 healthy male Chinese subjects who were genotyped for the CYP2D6*2, *5, *10, CYP3A5*3, CYP1A2*1F and ABCB1 C1236T, G2677T/A, and C3435T polymorphisms.

Concurrent use of proton pump inhibitors or H2 blockers did not adversely affect nilotinib efficacy in patients with chronic myeloid leukemia.

Purpose: The impact of proton pump inhibitors (PPIs) and histamine H2 receptor antagonists (H2 blockers) on the efficacy of nilotinib was evaluated.

Methods: Retrospective analyses were performed in patients with newly diagnosed Philadelphia chromosome-positive (Ph+) chronic myeloid leukemia in chronic phase (CML-CP; N = 492) and in patients with imatinib-resistant or imatinib-intolerant Ph+ CML-CP (N = 256) treated with nilotinib.

Results: In the newly diagnosed population, 87 (17.

Impact of CYP2D6 polymorphisms on the pharmacokinetics of lovastatin in Chinese subjects.

Purpose: Although CYP3A4/5 enzymes play the predominant role in the metabolism of simvastatin and lovastatin, polymorphisms in CYP2D6 were reported to be associated with the cholesterol-lowering effect and/or tolerability of simvastatin. This study was performed to examine whether common CYP2D6 polymorphisms affect the pharmacokinetics of lovastatin, which is taken as the inactive prodrug lovastatin lactone and converted to active lovastatin acid.

Methods: A single-dose pharmacokinetic study was performed with lovastatin in 23 Chinese healthy male subjects.

Population pharmacokinetic and exposure-response analysis of nilotinib in patients with newly diagnosed Ph+ chronic myeloid leukemia in chronic phase.

Purpose: We investigated the population pharmacokinetics and exposure-response relationship of nilotinib in patients with newly diagnosed chronic myeloid leukemia (CML) in chronic phase.

Methods: Nilotinib was given at 300 mg or 400 mg twice daily. Serum concentration data (sparse and full pharmacokinetic profiles) were obtained from 542 patients over 12 months.

Omeprazole limited sampling strategies to predict area under the concentration-time curve ratios: implications for cytochrome P450 2C19 and 3A phenotyping.

Purpose: To develop a limited sampling strategy (LSS) to predict area under the concentration-time curve (AUC) ratios of omeprazole (AUC(OPZ)) to its metabolites 5-hydroxyomeprazole (AUC(5OH)) and omeprazole sulfone (AUC(SUL)) as phenotyping parameters for cytochrome P450 (CYP) 2C19 and 3A.

Methods: Data were obtained from 37 (4 women) Caucasian, Chinese, and Korean healthy adults from three published studies. The AUC(OPZ), AUC(5OH), and AUC(SUL) were calculated via noncompartmental analysis.

Effects of yogurt and applesauce on the oral bioavailability of nilotinib in healthy volunteers.

Nilotinib, a potent orally bioavailable BCR-ABL tyrosine kinase inhibitor, is currently available as a hard gelatin capsule that must be swallowed whole. For patients who may have difficulty swallowing the intact capsule, an alternative mode of administration is desirable. The authors compared the bioavailability of nilotinib from the following administrations in 48 healthy subjects: (1) 400 mg nilotinib given as two 200-mg nilotinib intact capsules; (2) contents of two 200-mg nilotinib capsules, each capsule dispersed in 1 teaspoon of nonfat plain yogurt; and (3) contents of two 200-mg nilotinib capsules, each capsule dispersed in 1 teaspoon of applesauce.

Effects of nilotinib on single-dose warfarin pharmacokinetics and pharmacodynamics: a randomized, single-blind, two-period crossover study in healthy subjects.

Background And Objective: Nilotinib (Tasigna®), a highly selective and potent BCR-ABL tyrosine kinase inhibitor, is approved for the treatment of chronic myeloid leukaemia in the chronic phase (CML-CP) and the accelerated phase (CML-AP) in patients resistant or intolerant to prior therapy, including imatinib. Nilotinib has shown competitive inhibition of cytochrome P450 enzyme (CYP) 2C9 in vitro, but its effect on CYP2C9 activity in humans is unknown. This study evaluated the effects of nilotinib on the pharmacokinetics and pharmacodynamics of warfarin, a sensitive CYP2C9 substrate, in healthy subjects.

Effects of rifampin and ketoconazole on the pharmacokinetics of nilotinib in healthy participants.

Nilotinib (Tasigna), an orally bioavailable second-generation BCR-ABL tyrosine kinase inhibitor, is approved for use in patients with chronic myeloid leukemia in chronic phase and accelerated phase who are resistant or intolerant to prior therapy, including imatinib. Previous in vitro studies indicated that nilotinib metabolism is primarily mediated by CYP3A4. To investigate the effect of CYP3A4 induction and inhibition on nilotinib pharmacokinetics, 2 studies were conducted in healthy volunteers prior to and following treatment with a strong inducer (rifampin) or inhibitor (ketoconazole).

Effect of the proton pump inhibitor esomeprazole on the oral absorption and pharmacokinetics of nilotinib.

Nilotinib (Tasigna), a highly selective and potent BCR-ABL tyrosine kinase inhibitor (TKI), is administered orally and has pH-dependent aqueous solubility, with lower dissolution at higher pH. This study evaluated the effect of esomeprazole on the pharmacokinetics of nilotinib in healthy participants. Twenty-two participants (6 women, 16 men, mean age of 44.

CYP3A5 but not CYP2D6 polymorphism contributes significantly to the variability in dextropropoxyphene disposition.

This study evaluated the effect of CYP2D6, CYP3A4, and CYP3A5 polymorphisms on dextropropoxyphene disposition in healthy subjects. A total of 14 healthy male Chinese subjects received a single oral dose of a combination tablet of 325 mg of paracetamol and 32.5 mg of dextropropoxyphene.

Effects of hepatic impairment on the pharmacokinetics of nilotinib: an open-label, single-dose, parallel-group study.

Background: Nilotinib is a second-generation BCR-ABL tyrosine kinase inhibitor approved for the treatment of patients who have imatinib-resistant Philadelphia chromosome-positive chronic myeloid leukemia in the chronic or accelerated phase or who are unable to tolerate imatinib. Nilotinib is metabolized in the liver via oxidation and hydroxylation pathways, mediated primarily by the cytochrome P450 3A4 isozyme. Interpatient variability in systemic exposure to nilotinib has been reported to range from 32% to 64%.