There are 3 clinical trials

Clinical Trials

1 Characterisation of the Human Carboxylesterase 1 (CES1) Mutation(s) Which May be Responsible for Markedly Reduced Conversion of Oseltamivir Phosphate to Oseltamivir Carboxylate

The aim of this study is to evaluate the conversion of OP to OC in individual X and the family member of individual X. The investigators hypothesize that one or more of the single nucleoprotein polymorphisms (SNPs) of the CES1 gene represent a clinically important functional polymorphism.

NCT01443806 Metabolic Disease Drug: Oseltamivir

MeSH:Metabolic Diseases

A study from Zhu HJ et al presented potentially 2 functional polymorphisms locating in exon 4 (Gly143Glu) and 6 (Asp260fs) that can impair the CES1 hydrolytic activity to methylphenidate in vitro. --- Gly143Glu ---

2 Genetic Determinants of ACEI Prodrug Activation

Angiotensin-converting enzyme inhibitors (ACEIs) are among the most frequently prescribed medications worldwide for the treatment of essential hypertension, left ventricular systolic dysfunction, acute myocardial infarction, and prevention of the progression of diabetic nephropathy. However, the outcome of ACEI treatment varies significantly between individuals and selected populations. Suboptimal response, therapeutic failure, and significant side effects are commonly documented in patients receiving ACEI therapy. Approximately 80% of the ACEIs available for use in the US are synthesized as esterified prodrugs in order to improve otherwise poor oral bioavailability of the active molecule. The activation of ACEI prodrugs primarily occurs in the liver via metabolic de-esterification of the parent drug. The critical activation step is essential in delivering a successful therapeutic outcome since the active metabolites are approximately 10-1000 times more potent relative to their respective parent compounds. Carboxylesterase 1 (CES1), the most abundant hydrolase in the liver, is responsible for the activation of ACEI prodrugs in humans. Marked interindividual variability in CES1 expression and activity has been documented, which results in varied therapeutic efficacy and tolerability of many drugs serving as substrates of CES1. Genetic variation of CES1 is considered to be a major factor contributing to variability in CES1 function. The study team proposes to conduct a multiple-dose healthy volunteer study to evaluate the impact of CES1 genetic variation on the activation, pharmacokinetics, and pharmacodynamics of enalapril, a model ACEI prodrug activated by CES1. The completion of this study will represent a major step towards the establishment of an evidence base from which a more individualized use of ACEI prodrugs can emerge.

NCT03051282 Healthy Volunteers Drug: Enalapril

To compare the mean AUC of enalaprilat plasma concentrations between the non-carrier control and the G143E carriers groups. --- G143E ---

To compare the maximum enalaprilat plasma concentrations between the non-carrier control and the G143E carriers groupsG143E carriers groups. --- G143E ---

To compare the plasma ACE activity between the non-carrier control and the G143E carriers groupsG143E carriers groups following enalapril treatment. --- G143E ---

To compare the changes of BPs between the non-carrier control and the G143E carriers groupsG143E carriers groups following enalapril treatment. --- G143E ---

- A positive urine pregnancy test in the MCRU prior to the study - No subjects weighing under 50 kg will be selected - The lack of use of acceptable methods of birth control unless abstinent - Subjects who regularly take medications, vitamins, herbal supplements - The use of any illicit drugs or habitual consumption of large quantities of ethanol (>3 drinks/day) - The consumption of grapefruit or grapefruit juice a week prior to, and during the study - Asians will not be included in the study as the CES1 SNP G143E is absent in this population - Subjects hypersensitive to enalapril - Subject with a history of angioedema - Smokers Inclusion Criteria: - Subjects must be male and female (50:50) between the ages of 18-55 years - Females must have a negative urine pregnancy test prior to the study - All subjects must have no clinically significant diseases or clinically significant abnormal laboratory values as assessed during the screening medical history, nursing assessment, and laboratory evaluations - Informed consent must be signed by the eligible subject prior to the initiation of any study procedures Exclusion Criteria: - The presence of a known medical condition that would preclude the use of enalapril - The presence of any surgical or medical condition (active or chronic) that may interfere with drug absorption, distribution, metabolism, or excretion. --- G143E ---

- A positive urine pregnancy test in the MCRU prior to the study - No subjects weighing under 50 kg will be selected - The lack of use of acceptable methods of birth control unless abstinent - Subjects who regularly take medications, vitamins, herbal supplements - The use of any illicit drugs or habitual consumption of large quantities of ethanol (>3 drinks/day) - The consumption of grapefruit or grapefruit juice a week prior to, and during the study - Asians will not be included in the study as the CES1 SNP G143E is absent in this population - Subjects hypersensitive to enalapril - Subject with a history of angioedema - Smokers Healthy Volunteers null --- G143E ---

3 Carboxylesterase 1 Genetic Variation and Methylphenidate in ADHD

The study team will determine the association between d,l-methylphenidate (MPH) therapeutic outcomes in ADHD patients and genetic variants of CES1 and reveal key associations between CES1 genotypes and the PK and PD of MPH.

NCT03781752 ADHD Attention Deficit Hyperactivity Disorder Drug: Methylphenidate

MeSH:Attention Deficit Disorder with Hyperactivity

HPO:Attention deficit hyperactivity disorder

The first clinically significant CES1 variant G143E (rs71647871), discovered in the study team's lab during the course of a healthy volunteer MPH PK study, led to gross impairments in MPH metabolism. --- G143E ---

The study team has established the minor allele frequency (MAF) of the G143E variant as 3-4% in the general population. --- G143E ---

G143E carrier's frequency 6-8%) with a genetically impaired ability to metabolize/deactivate the drug will receive it - exposing them to high systemic concentrations of MPH and any attendant risks or toxicities. --- G143E ---

The study team's hypothesis is that the CES1 variants, such as the G143E and D203E, can significantly alter the expression and/or activity of CES1, thereby influencing the metabolism and disposition of MPH. --- G143E ---

HPO Nodes