NCT05469204

Effect of Estrogen Treatment on Drug Metabolism and Transport

Effect of Gender-Affirming Estrogen Therapy on Drug Metabolism, Transport, and Gut Microbiota

• Status: Completed
• Phase: Phase 4
• Study type: Interventional
• Enrollment: 22 (actual)
• Sponsor: University of Washington · Academic / Other
• Sex: All
• Age: 18 Years – 55 Years
• Healthy volunteers: Accepted

Summary

This project will evaluate the effect of estrogen treatment on how other medications are processed by the body.

Detailed description

Estradiol is prepared as a medication that patients may take to increase hormone levels. Changes in estradiol concentrations in the body may affect how the body processes other medicines. The purpose of this study is to find out how estradiol therapy affects a single tracer dose of approved medicines in the blood (midazolam, digoxin, and acetaminophen) and to confirm estradiol treatment does not affect natural bacterial in the gut.

Conditions

• Transgender Persons

Interventions

Type	Name	Description
DRUG	Midazolam oral solution	2 mg single-dose before and during estradiol treatment.
DRUG	Digoxin Oral Tablet	0.25 mg single-dose before and during estradiol treatment.
DRUG	Acetaminophen Oral Tablet	500 mg single-dose before and during estradiol treatment.
DRUG	Midazolam Injectable Solution	1 mg intravenous single-dose before and during estradiol treatment.

Timeline

• Start date: 2022-11-01
• Primary completion: 2025-07-30
• Completion: 2025-07-30
• First posted: 2022-07-21
• Last updated: 2026-01-09

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study