Rivaroxaban is an oral, direct Factor Xa inhibitor that targets free and clot-bound Factor Xa and Factor Xa in the prothrombinase complex. It is absorbed rapidly, with maximum plasma concentrations ...being reached 2–4 h after tablet intake. Oral bioavailability is high (80–100 %) for the 10 mg tablet irrespective of food intake and for the 15 mg and 20 mg tablets when taken with food. Variability in the pharmacokinetic parameters is moderate (coefficient of variation 30–40 %). The pharmacokinetic profile of rivaroxaban is consistent in healthy subjects and across a broad range of different patient populations studied. Elimination of rivaroxaban from plasma occurs with a terminal half-life of 5–9 h in healthy young subjects and 11–13 h in elderly subjects. Rivaroxaban produces a pharmacodynamic effect that is closely correlated with its plasma concentration. The pharmacokinetic and pharmacodynamic relationship for inhibition of Factor Xa activity can be described by an
E
max
model, and prothrombin time prolongation by a linear model. Rivaroxaban does not inhibit cytochrome P450 enzymes or known drug transporter systems and, because rivaroxaban has multiple elimination pathways, it has no clinically relevant interactions with most commonly prescribed medications. Rivaroxaban has been approved for clinical use in several thromboembolic disorders.
Doses of 10 mg, 15 mg, and 20 mg of rivaroxaban are approved for the treatment and prevention of thromboembolic disorders in adult patients. In six Phase I studies, the pharmacokinetics, safety, and ...tolerability of 2.5 mg, 5 mg, 10 mg, 15 mg, and 20 mg rivaroxaban were investigated in healthy male subjects, and the influence of food on these parameters was investigated for the 10 mg, 15 mg, and 20 mg tablet doses. In addition, an oral suspension containing 1 mg/ml rivaroxaban, which is under investigation for future use in the pediatric population, was investigated at doses of 10 mg and 20 mg.
Rivaroxaban was obtained from Bayer Pharma AG, Wuppertal, Germany.
Six independent, single-dose, cross-over studies were performed in healthy male subjects (between 13 and 24 subjects were enrolled in each study) to determine the pharmacokinetics, safety, and tolerability of rivaroxaban under fasting and fed conditions. Study 1 was an absolute bioavailability study that compared 5 mg and 20 mg tablet doses with a 1 mg intravenous solution. Studies 2 and 3 were confirmatory food-effect studies that assessed 10 mg and 20 mg tablet doses, respectively, under fed and fasting conditions. Study 4 was a formulation study that evaluated oral suspensions of 10 mg (fasting) and 20 mg (fasting and fed) rivaroxaban vs. a 10 mg tablet (fasted). Study 5 was a dose-proportionality study that assessed 2.5 mg, 5 mg, and 10 mg tablets under fasting conditions. Study 6 was a dose-proportionality study that assessed tablet doses of 10 mg, 15 mg, and 20 mg under fed conditions. Pharmacokinetic parameters, including the area under the plasma concentration-time curve after a single dose, the maximum drug concentration in plasma after a single dose, dose-adjusted values of area under the plasma concentration-time curve and maximum drug concentration in plasma after a single dose, half-life associated with the terminal slope, and time to maximum concentration in plasma after a single dose were evaluated. Adverse events were classified according to their degree of severity and were summarized using Medical Dictionary for Regulatory Activities preferred terms.
At all doses, rivaroxaban showed an acceptable safety profile and was well tolerated in healthy individuals. Independent of food and formulation, pharmacokinetic parameters of doses up to 10 mg rivaroxaban were dose proportional and had high oral bioavailability (≥ 80%). Under fasting conditions, pharmacokinetic parameters of 15 mg and 20 mg rivaroxaban increased with dose but were less than dose proportional. However, when taken with food, high bioavailability (≥ 80%) of these doses was achieved independent of formulation.
Pharmacokinetic parameters of doses up to 10 mg rivaroxaban were dose proportional and had high oral bioavailability independent of food or whether administered as tablet or solution. High bioavailability (≥ 80%) of 15 mg and 20 mg rivaroxaban was achieved when taken with food; therefore, these doses need to be taken with food.
A randomized, single‐blind, placebo‐controlled, parallel‐group study was conducted to assess the effect of age and gender on the pharmacokinetics and pharmacodynamics of rivaroxaban – an oral, direct ...Factor Xa inhibitor. Subjects (n = 34) were enrolled into four groups: young males or females (aged 18–45 years) and elderly males or females (aged >75 years), and received a single dose of 10 mg rivaroxaban. Pharmacokinetic and pharmacodynamic parameters were determined. Gender had no significant influence on the pharmacokinetics and pharmacodynamics of rivaroxaban. The area under the concentration–time curve (AUC) of rivaroxaban was 41% higher in elderly compared with young subjects; corresponding AUC values for the inhibition of Factor Xa activity and prolongation of prothrombin time were also higher. These changes were the result of reduced rivaroxaban clearance in elderly subjects, mainly owing to decreased renal function. The influence of age was not considered clinically relevant. The maximum plasma concentration was not increased in elderly subjects, and pharmacodynamic parameters returned close to baseline within 24 hours. The results indicate that age alone and gender did not have a clinically relevant effect on the pharmacokinetics and pharmacodynamics of rivaroxaban in healthy subjects after a 10 mg dose.
Anticoagulants are often dose adjusted, or their use restricted, in patients with extremes of body weight. Rivaroxaban (BAY 59‐7939) is a novel, oral, direct factor Xa inhibitor in clinical ...development. This was a randomized, single‐blind, placebo‐controlled, parallel‐group study in healthy male and female subjects to assess the effect of extreme body weight (≤50 kg and >120 kg), and gender, on the safety, tolerability, pharmacokinetics, and pharmacodynamics of rivaroxaban 10 mg, compared with subjects of normal weight (70–80 kg). Rivaroxaban was well tolerated. Cmax of rivaroxaban was unaffected in subjects >120 kg but was increased by 24% in subjects weighing ≤5 0 kg, resulting in a small (15%) increase in prolongation of prothrombin time, which was not considered clinically relevant. The area under the curve was unaffected by body weight or gender. No other clinically relevant differences were observed, suggesting that rivaroxaban is unlikely to require dose adjustment for body weight or gender.
Abstract
Background
The protease chymase generates multiple factors involved in tissue remodelling including angiotensin II (Ang II) and has been implicated in the pathophysiology of diabetic kidney ...disease (DKD). This study investigated the effects of the chymase inhibitor fulacimstat on albuminuria in patients with Type II diabetes mellitus and a clinical diagnosis of DKD.
Methods
In this double-blind, randomized, placebo-controlled trial, patients were on the maximum tolerated dose of either an Ang II receptor blocker or an Ang-converting enzyme inhibitor since at least 3 months before the screening visit. Eligible patients were randomized in a 2:1 ratio to treatment with either 25 mg fulacimstat (n = 99) or placebo (n = 48) twice daily on top of standard of care.
Results
The randomized patients had a mean urine albumin–creatinine ratio (UACR) of 131 mg/g (range: 29–2429 mg) and a mean (standard deviation) estimated glomerular filtration rate of 60.8 ± 16.9 mL/min/1.73 m2 before treatment start. Fulacimstat was safe and well tolerated, and achieved mean total trough concentrations that were ∼9-fold higher than those predicted to be required for minimal therapeutic activity. UACR increased by 27.4% coefficient of variation (CV) 86% and 3% (CV 88.9%) after 24 weeks of treatment with placebo or fulacimstat, respectively. Analysis of covariance revealed a least square mean UACR ratio (fulacimstat/placebo) of 0.804 (90% CI 0.627–1.030, P = 0.1477), indicating a statistically non-significant UACR reduction of 19.6% after fulacimstat treatment compared with placebo.
Conclusions
Fulacimstat was safe and well tolerated but did not reduce albuminuria in patients with DKD. These findings do not support a therapeutic role for chymase inhibition in DKD.
ABSTRACT
Objective: The aim of this study was to investigate the pharmacokinetics and pharmacodynamics of rivaroxaban - a novel, oral, direct Factor Xa (FXa) inhibitor - in healthy elderly subjects.
...Research design and methods: In this single-centre, single-blind, placebo-controlled, parallel-group, dose-escalation study, 48 subjects (aged 60-76 years) were randomized to receive a single oral dose of 30, 40 or 50 mg of rivaroxaban or placebo.
Results: Rivaroxaban was absorbed rapidly, reaching peak plasma concentration (Cmax) 4 h after dosing in all groups. Bioavailability, in terms of the area under the plasma concentration-time curve (AUC) and Cmax, increased slightly (less than dose proportionally) after administration of rivaroxaban 40 mg compared with 30 mg, but was not increased further with rivaroxaban 50 mg. Rivaroxaban pharmacodynamic effects (inhibition of FXa activity and prolongation of prothrombin time, activated partial thromboplastin time and HepTest) all showed a similar pattern, with maximum inhibition of FXa activity increasing from 68% after rivaroxaban 30 mg to 75% after 40 mg and no further increase with the 50 mg dose. Most adverse events were mild; observed rates were less than placebo for the 30 and 40 mg dose groups, and similar to placebo for 50 mg. No differences were found between male and female subjects. Effects of rivaroxaban doses above 50 mg were not investigated in this study.
Conclusions: Each single dose of rivaroxaban was well tolerated, with predictable pharmacokinetics and pharmacodynamics at doses up to 40 mg, and provided effective anticoagulation in healthy elderly subjects. Adverse events were somewhat elevated in the 50 mg group, but given the small sample size, no specific conclusions can be drawn about this dosing level.
To investigate the influence of food and administration of an antacid (aluminum‐magnesium hydroxide) or ranitidine on the absorption of BAY 59–7939 (rivaroxaban), 4 randomized studies were performed ...in healthy male subjects. In 2 food interaction studies, subjects received BAY 59–7939, either as two 5‐mg tablets (fasted and fed), four 5‐mg tablets (fasted), or one 20‐mg tablet (fasted and fed). In 2 drug interaction studies, BAY 59–7939 (six 5‐mg tablets) was given alone or with ranitidine (150 mg twice daily, preceded by a 3‐day pretreatment phase) or antacid (10 mL). Plasma samples were obtained to assess pharmacokinetic and pharmacodynamic parameters of BAY 59–7939. In the presence of food, time to maximum concentration (tmax) was delayed by 1.25 hours; maximum concentration (Cmax) and area under the curve (AUC) were increased, with reduced interindividual variability at higher doses of BAY 59–7939. Compared with baseline, BAY 59–7939 resulted in a relative increase in maximum prothrombin time (PT) prolongation of 44% (10 mg) and 53% (20 mg) in the fasted state, compared with 53% and 83% after food. Time to maximum PT prolongation was delayed by 0.5 to 1.5 hours after food, with no relevant influence of food type. No significant difference in Cmax and AUC was observed with coadministration of BAY 59–7939 and ranitidine or antacid.
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT
• Prior to the commencement of this study, it was already known that rivaroxaban is partially cleared via the kidneys and an influence of renal insufficiency ...on rivaroxaban pharmacokinetics and exposure was anticipated.
WHAT THIS STUDY ADDS
• As many patients in the target indications of rivaroxaban will be elderly, a precise quantitative knowledge of the influence of renal function on rivaroxaban pharmacokinetics and exposure is mandatory for adequate labelling recommendations (in the context of benefit/risk provided by phase III studies) to guide therapy. This study provided detailed insight on both rivaroxaban pharmacokinetics and pharmacodynamic behaviour in renal impairment including severely renally impaired subjects.
AIM
This study evaluated the effects of impaired renal function on the pharmacokinetics, pharmacodynamics and safety of rivaroxaban (10 mg single dose), an oral, direct Factor Xa inhibitor.
METHODS
Subjects (n= 32) were stratified based on measured creatinine clearance: healthy controls (≥80 ml min−1), mild (50–79 ml min−1), moderate (30–49 ml min−1) and severe impairment (<30 ml min−1).
RESULTS
Renal clearance of rivaroxaban decreased with increasing renal impairment. Thus, plasma concentrations increased and area under the plasma concentration–time curve (AUC) LS‐mean values were 1.44‐fold (90% confidence interval CI 1.1, 1.9; mild), 1.52‐fold (90% CI 1.2, 2.0; moderate) and 1.64‐fold (90% CI 1.2, 2.2; severe impairment) higher than in healthy controls. Corresponding values for the LS‐mean of the AUC for prolongation of prothrombin time were 1.33‐fold (90% CI 0.92, 1.92; mild), 2.16‐fold (90% CI 1.51, 3.10 moderate) and 2.44‐fold (90% CI 1.70, 3.49 severe) higher than in healthy subjects, respectively. Likewise, the LS‐mean of the AUC for Factor Xa inhibition in subjects with mild renal impairment was 1.50‐fold (90% CI 1.07, 2.10) higher than in healthy subjects. In subjects with moderate and severe renal impairment, the increase was 1.86‐fold (90% CI 1.34, 2.59) and 2.0‐fold (90% CI 1.44, 2.78) higher than in healthy subjects, respectively.
CONCLUSIONS
Rivaroxaban clearance is decreased with increasing renal impairment, leading to increased plasma exposure and pharmacodynamic effects, as expected for a partially renally excreted drug. However, the influence of renal function on rivaroxaban clearance was moderate, even in subjects with severe renal impairment.
There is a clinical need for safe new oral anticoagulants. The safety, tolerability, pharmacodynamics, and pharmacokinetics of BAY 59-7939--a novel, oral, direct Factor Xa (FXa) inhibitor--were ...investigated in this single-center, placebo-controlled, single-blind, parallel-group, multiple-dose escalation study.
Healthy male subjects (aged 20-45 years, body mass index 18.6-31.4 kg/m(2)) received oral BAY 59-7939 (n=8 per dose regimen) or placebo (n=4 per dose regimen) on days 0 and 3-7. Dosing regimens were 5 mg once, twice (bid), or three times daily, and 10 mg, 20 mg, or 30 mg bid.
There were no clinically relevant changes in bleeding time or other safety variables across all doses and regimens. There was no dose-related increase in the frequency or severity of adverse events with BAY 59-7939. Maximum inhibition of FXa activity occurred after approximately 3 h, and inhibition was maintained for at least 12 h for all doses. Prothrombin time, activated partial thromboplastin time, and HepTest were prolonged to a similar extent to inhibition of FXa activity for all doses. Dose-proportional pharmacokinetics (AUC(tau, norm) and C(max, norm)) were observed at steady state (day 7). Maximum plasma concentrations were achieved after 3-4 h. The terminal half-life of BAY 59-7939 was 5.7-9.2 h at steady state. There was no relevant accumulation at any dose.
BAY 59-7939 was safe and well tolerated across the wide dose range studied, with predictable, dose-proportional pharmacokinetics and pharmacodynamics and no relevant accumulation beyond steady state. These results support further investigation of BAY 59-7939 in phase II clinical trials.
Background & Aims:
Histologic examination of a liver biopsy specimen is regarded as the reference standard for detecting liver fibrosis. Biopsy can be painful and hazardous, and assessment is ...subjective and prone to sampling error. We developed a panel of sensitive automated immunoassays to detect matrix constituents and mediators of matrix remodeling in serum to evaluate their performance in the detection of liver fibrosis.
Methods:
In an international multicenter cohort study, serum levels of 9 surrogate markers of liver fibrosis were compared with fibrosis stage in liver biopsy specimens obtained from 1021 subjects with chronic liver disease. Discriminant analysis of a test set of samples was used to identify an algorithm combining age, hyaluronic acid, amino-terminal propeptide of type III collagen, and tissue inhibitor of matrix metalloproteinase 1 that was subsequently evaluated using a validation set of biopsy specimens and serum samples.
Results:
The algorithm detected fibrosis (sensitivity, 90%) and accurately detected the absence of fibrosis (negative predictive value for significant fibrosis, 92%; area under the curve of a receiver operating characteristic plot, .804; standard error, .02;
P < .0001; 95% confidence interval, .758–.851). Performance was excellent for alcoholic liver disease and nonalcoholic fatty liver disease. The algorithm performed equally well in comparison with each of the pathologists. In contrast, pathologists’ agreement over histologic scores ranged from very good to moderate (κ = .97–.46).
Conclusions:
Assessment of liver fibrosis with multiple serum markers used in combination is sensitive, specific, and reproducible, suggesting they may be used in conjunction with liver biopsy to assess a range of chronic liver diseases.
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