Publications by authors named "Atsuhiro Kawaguchi"

Article Synopsis
  • - Dersimelagon is a selective medication being tested for treating certain rare disorders like erythropoietic protoporphyria and systemic sclerosis, but it is heavily processed by the liver, raising concerns for patients with liver issues.
  • - Two studies were conducted to assess how liver and kidney impairments affect the drug's pharmacokinetics, which involves how the drug is absorbed and metabolized in the body.
  • - Results showed that while mild liver impairment had similar effects on the drug, moderate impairment increased its concentration in the bloodstream significantly, and renal impairment also affected drug levels, though Dersimelagon was generally well tolerated among participants.
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Introduction: Drugs often show differing pharmacokinetic (PK) profiles, such as higher plasma concentrations, in older people than in younger people owing to age-related decreases in physiological functions. However, it is difficult to evaluate the PK in older populations. Therefore, we simulated the plasma age-related changes in the PK of teneligliptin, a dipeptidyl peptidase-4 inhibitor, using physiologically based PK (PBPK) models.

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Purpose: To characterize the clinical relevance of in vitro drug-drug interaction findings with apararenone (MT-3995), the effects of apararenone on the sensitive substrates of cytochrome P450 3A4 (midazolam) and 2C9 (warfarin), and P-glycoprotein (digoxin), were assessed through a series of studies conducted in healthy volunteers.

Methods: Three studies were conducted in 56 healthy adults. Study 1 investigated the effects of the administration of apararenone with midazolam; apararenone was administered on days 2 (320 mg) and days 3-15 (20 mg/d), and midazolam 2 mg, on days 1 and 15.

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The International Consortium for Innovation and Quality in Pharmaceutical Development (IQ) Clinical Pharmacology Leadership Group (CPLG) held its first meeting of Japan-based representatives at Astellas Pharma headquarters in Tokyo on October 1, 2019. The meeting was also attended by Japan Pharmaceutical Manufactures Association (JPMA) Clinical Pharmacology Task Force (CPTF) members. Overall, nearly 30 clinical pharmacologists representing 14 companies attended the event.

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Apararenone is a long-acting, nonsteroidal mineralocorticoid receptor antagonist (MRA). The safety, tolerability, and pharmacokinetic (PK) and pharmacodynamic (PD) profiles of single- and multiple-dose apararenone were assessed in 3 phase 1 randomized, double-blind studies in 223 healthy adults. Study 1 assessed the PK, safety/tolerability, and PD of single-dose apararenone (3.

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The absorption, metabolism and excretion of MT-1303 were investigated in healthy male subjects after a single oral dose of 0.4 mg [14C]-MT-1303 (ClinicalTrials.gov NCT02293967).

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Background: Amyotrophic lateral sclerosis (ALS) affects persons of all races, and there continues to be a need for effective therapies to treat the disease.

Objective: To compare the pharmacokinetics (PK) of edaravone between Japanese and Caucasian populations.

Methods: Data from five PK studies among Japanese and Caucasian healthy volunteers were pooled and evaluated.

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Article Synopsis
  • Researchers studied amiselimod (MT-1303), a new medication aimed at minimizing heart-related side effects (like bradycardia) typical of similar drugs like fingolimod.
  • The drug was shown to selectively activate specific receptors in the heart with reduced impact compared to fingolimod, evidenced by animal tests and telemetry in monkeys showing no changes in heart rate.
  • Human trials indicated that while lymphocyte counts decreased over time, there were no significant heart rate issues or bradycardia, suggesting amiselimod may be safe and effective without needing dose adjustments.
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Objective: The aim of this study was to examine the effect of ketoconazole, a potent cytochrome P450 (CYP) 3A4 and P-glycoprotein (P-gp) inhibitor, on teneligliptin pharmacokinetics and to evaluate the safety of combined administration of teneligliptin with ketoconazole.

Methods: This open-label, fixed-sequence study was conducted in 16 healthy adult volunteers in Germany. On day 1, under fasting conditions, 20 mg of teneligliptin was administered to evaluate the pharmacokinetics of teneligliptin alone.

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Aims: Two double-blind, randomized studies were conducted to assess the tolerability, pharmacokinetics and pharmacodynamics of oral TA-8995, a new cholesteryl ester transfer protein (CETP) inhibitor, in healthy subjects.

Methods: Study 1: Subjects received single doses of TA-8995 or placebo (fasted). Doses were 5, 10, 25, 50 (fed/fasted), 100 and 150 mg (Caucasian males, 18-55 years), 25 mg (Caucasian males, > 65 years and Caucasian females, 18-55 years), 25, 50, 100 and 150 mg (Japanese males, 18-55 years).

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1. The absorption, metabolism and excretion of teneligliptin were investigated in healthy male subjects after a single oral dose of 20 mg [(14)C]teneligliptin. 2.

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We conducted an open-label, parallel-group study of the high purity, mass-produced recombinant human serum albumin (rHSA), derived from the methylotrophic yeast Pichia pastoris, to compare pharmacokinetics and ensure bioequivalence with plasma-derived human serum albumin (pHSA) in 22 patients with liver cirrhosis. Both rHSA and pHSA groups enrolled 11 patients each, assigned according to predose serum albumin concentrations using the minimization method. Pharmacokinetic and safety profiles for 3-day repeated intravenous infusions at a daily dose of 25 g were evaluated for 8 days.

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The dialyzability of imidaprilat, an active metabolite of the angiotensin-converting enzyme (ACE) inhibitor imidapril, was determined and compared with those of enalaprilat and quinaprilat in hypertensive patients on chronic hemodialysis. Imidapril (5 mg/d, n = 6), enalapril (2.5 mg/d, n = 6), or quinapril (2.

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Aim: Undergraduate students in Jichi Medical School participated in a laboratory exercise investigating the furosemide-probenecid interaction at the end of their clinical pharmacology (CP) course. The aim of this study was to determine whether they learned to recognize drug interactions better than students who did not take such a course.

Methods: We conducted a postal survey of physicians who had graduated from Jichi Medical School or from other medical schools without a CP course including the exercise.

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Objective: Grapefruit juice (GFJ) inhibits cytochrome P450 (CYP) 3A4 in the gut wall and increases blood concentrations of CYP3A4 substrates by the enhancement of oral bioavailability. The effects of GFJ on two benzodiazepine hypnotics, triazolam (metabolized by CYP3A4) and quazepam (metabolized by CYP3A4 and CYP2C9), were determined in this study.

Methods: The study consisted of four separate trials in which nine healthy subjects were administered 0.

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Aim: St John's Wort (SJW) enhances CYP3A4 activity and decreases blood concentrations of CYP3A4 substrates. In this study, the effects of SJW on a benzodiazepine hypnotic, quazepam, which is metabolized by CYP3A4, were examined.

Methods: Thirteen healthy subjects took a single dose of quazepam 15 mg after treatment with SJW (900 mg day(-1)) or placebo for 14 days.

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Background/aims: Colorectal perforation remains a life-threatening condition associated with high mortality. Various factors and operative procedures have been discussed in regard to prediction of outcome, and several scoring systems have been proposed to predict the outcome of critically ill patients. The present study was undertaken to identify factors and determine predictive scoring systems for the postoperative outcome of patients with colorectal perforation.

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(+)-(R)-trans-4-(1-aminoethyl)-N-(4-pyridyl)-cyclohexanecarboxamide dihydrochloride (Y-27632), a Rho kinase inhibitor, has a suppressive effect on the functions of polymorphonuclear leukocytes. In this study, the influence of Y-27632 on ischemia-reperfusion injury of the liver was examined in rats. Y-27632 (3 mg/kg) or vehicle alone was intravenously injected into rats 60 min before occlusion.

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Rho-kinase regulates the actin cytoskeleton and therefore modulates transport. The role of Rho-kinase in Na-H exchanger (NHE) activity of rat proximal convoluted tubules (PCTs) was investigated using (R)-(+)-trans-N-(4-pyridyl)-4-(1-aminoethyl)-cyclohexanecarboxamide (Y-27632), a specific inhibitor of Rho-kinase. In spontaneously hypertensive rats (SHR) and Wistar Kyoto (WKY) rats, apical and basolateral NHE activities were determined by measuring cell pH recovery following luminal NH4+ prepulse and basolateral sodium removal, respectively.

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We evaluated the biocompatibility of a newly developed vitamin E hemodialyzer (CL-EE; Terumo Co Ltd, Tokyo, Japan) by neutrophil function and oxidant stress in patients with end-stage renal failure in a randomized crossover study. Ten patients underwent hemodialysis using either the CL-EE or a control dialyzer membrane identical to the CL-EE except for vitamin E binding for 12 weeks in a crossover fashion after a 1-month washout period with hemophane membranes. White blood cell counts, serum oxidized low-density lipoprotein (Ox-LDL) levels, and malondialdehyde (MDA) levels during hemodialysis sessions were measured at the initiation and end of the CL-EE and control trials.

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