Skip to content

Studies of Sulfur Metabolism in Humans

Allosteric Regulation of Cytosolic Sulfotransferases in Humans

Status
Completed
Phases
Early Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03383133
Enrollment
1
Registered
2017-12-26
Start date
2018-01-11
Completion date
2023-02-02
Last updated
2023-10-27

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Metabolic Side Effects of Drugs

Keywords

sulfotransferase, metabolism, acetaminophen, dehydroepiandrosterone, mefenamic acid, allostery

Brief summary

The study test whether the NSAID allosteric site of human sulfotransferase 1A1 (SULT1A1) is operative in humans. The study will test the effects of mefenamic acid (MEF) on the sulfonation of acetaminophen (APAP, a SULT1A1 specific substrate) and dehydroepiandrosterone (DHEA, a SULT2A1 substrate). If the allosteric site is active in vivo, MEF is predicted to result in a decrease in sulfonation of APAP (MEF inhibits SULT with high affinity (Ki = 23 nM), and to have no effect on sulfonation of the DHEA (MEF has little or no effect on SULT2A1 activity).

Detailed description

No patient registries associated with this study. A single, therapeutic dose of acetaminophen (APAP, 1.0 g)) or dehydroepiandrosterone (DHEA, 75 mg) is taken orally (with 375 ml of water) either alone or simultaneously with a single, oral, therapeutic dose of mefenamic acid (MEF, 0.75 g). In total, 5 experiments will be performed: 1, APAP alone; 2, DHEA alone; 3, MEF alone; 4, APAP + MEF; and 5, DHEA + MEF. Each experiment will be performed in duplicate. Compounds will be taken prior to eating breakfast. One hour later, the patient has a light breakfast (Cheerios and milk, and a cup of coffee) and eats normally thereafter. Urine samples are collected at 15', 30', 1 h, 2h, 3h, 4h, 5 h, 6h, 7h, 8h, 9h, 10h, 11h, and 12h intervals following dosing. The study subject will attempt to completely empty their bladder at each urine-collection time point. The samples are weighed. A 10 ml aliquot is taken from each time point and the aliquots are stored at -20 °C. Samples (0.5 ml) are then transferred to nuclear magnetic resonance (NMR) tubes and NMR spectra are taken to assess drug metabolites in urine. Proton NMR will be performed using the 600 MHz instrument in the Einstein facility.

Interventions

DRUGSULT Allosteric Inhibition

A single, therapeutic dose of acetaminophen (APAP, 1.0 g)) or dehydroepiandrosterone (DHEA, 75 mg) is taken orally (with 375 ml of water) either alone or simultaneously with a single, oral, therapeutic dose of mefenamic acid (MEF, 0.75 g). In total, 5 experiments will be performed. Each experiment is performed in duplicate. Compounds are taken prior to eating breakfast. One hour later, the patient has a light breakfast and eats normally thereafter. Urine samples are collected at 15', 30', 1 h, 2h, 3h, 4h, 5 h, 6h, 7h, 8h, 9h, 10h, 11h, and 12h intervals following dosing. The samples are weighed. A 10 ml aliquot is taken from each time point and the aliquots are stored at -20 °C. Samples (0.5 ml) are then transferred to NMR tubes spectra are taken to assess drug metabolites in urine.

Sponsors

Albert Einstein College of Medicine
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE

Intervention model description

This study will involve only a single individual.

Eligibility

Sex/Gender
MALE
Age
61 Years to 61 Years
Healthy volunteers
No

Inclusion criteria

* Gender - one male * Age - 61 y.o. * Healthy * Agreed to sign the consent form

Exclusion criteria

● None

Design outcomes

Primary

MeasureTime frameDescription
Acetaminophen and Dehydroepiandrosterone Conjugates15min, 30min, 1hr, 2hr, 3hr, 4hr, 5hr, 6hr, 7hr, 8hr, 9hr, 10hr, 11hr, and 12hr following administration.Proton NMR Signals will be used to quantitate conjugates of acetaminophen and dehydroepiandrosterone in urine.

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026