What side effects are associated with this type of intervention?

Estrogen therapy, used in transgender women to induce feminizing effects and suppress testosterone, can lead to side effects such as an increased risk of thromboembolic events, cardiovascular issues, elevated liver enzymes, and changes in lipid profiles. Other side effects include breast tenderness, mood changes, and decreased libido. Patients should discuss these potential side effects with their healthcare provider to manage risks effectively.

What prior FDA approvals exist?

The FDA has approved several treatments for transgender individuals seeking feminizing effects and testosterone suppression. Estrogen therapy, often in the form of estradiol, is commonly used to induce feminizing effects and suppress testosterone levels. Additionally, anti-androgens such as spironolactone are frequently used in combination with estrogen to further reduce testosterone levels. These treatments are part of gender-affirming hormone therapy protocols aimed at aligning physical characteristics with gender identity.

What other types of research exist?

Currently, there are no widely recognized novel alternatives to estrogen for inducing feminizing effects and suppressing testosterone in transgender patients. Estrogen remains the primary treatment. However, ongoing research in gender-affirming hormone therapy (GAHT) may yield new options in the future. Patients should consult with their healthcare providers to stay informed about emerging treatments.

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Hormone Therapy

Estradiol Therapy for Transgender Women (TREAT Trial)

Phase 2

Recruiting

Led By Ginger Nicol, MD

Research Sponsored by Washington University School of Medicine

Eligibility Criteria Checklist

Specific guidelines that determine who can or cannot participate in a clinical trial

Must have

Be between 18 and 65 years old

Timeline

Screening 3 weeks

Treatment Varies

Follow Up change from baseline total testosterone level at 6,12,18, and 24 months

Awards & highlights

TREAT Trial Summary

This trial is testing whether estrogen is an effective and safe medication for transgender women, and whether it suppresses testosterone levels.

Who is the study for?

This trial is for transgender female patients aged 18-30 who are eligible and ready for gender-affirming hormone therapy, seen at the Washington University Transgender Center. It's not open to those with a history of liver disease, dyslipidemia needing treatment, BMI over 30, or current smokers.Check my eligibility

What is being tested?

The study tests the effectiveness and safety of estrogen treatments in suppressing testosterone among transgender females. Participants will receive either spironolactone pills or transdermal patches while monitoring hormone and metabolic markers.See study design

What are the potential side effects?

Possible side effects include changes in blood pressure from spironolactone, skin irritation from patches, shifts in metabolic markers which could affect energy levels and weight, as well as potential increases in pro-thrombotic markers that might raise clotting risks.

TREAT Trial Timeline

Screening ~ 3 weeks3 visits

Treatment ~ Varies

Follow Up ~ change from baseline homa-ir at 6,12,18, and 24 months

Screening ~ 3 weeks

Treatment ~ Varies

Follow Up ~change from baseline homa-ir at 6,12,18, and 24 months

This trial's timeline: 3 weeks for screening, Varies for treatment, and change from baseline homa-ir at 6,12,18, and 24 months for reporting.

Treatment Details

Study Objectives

Outcome measures can provide a clearer picture of what you can expect from a treatment.

Primary outcome measures

Degree of testosterone suppression by measuring total testosterone level in transgender female patients undergoing hormonal affirming therapy

Secondary outcome measures

Coagulation factors II, IX, XI, Protein C, Protein S, von Willebrand factor, and activated protein C resistance in transgender female patients undergoing

Homeostatic Model Assessment for Insulin Resistance

Llipid panel

+1 more

TREAT Trial Design

3Treatment groups

Active Control

Group I: Twice daily sublingual estradiol plus spironolactoneActive Control5 Interventions

Starting dose will be 1 mg twice daily Plan to increase every month by 2 mg daily divided BID Goal is to achieve serum estradiol level between 100-200 pg/mL mL and to suppress testosterone to cisgender female levels All patients will also receive spironolactone. Spironolactone will be started at 50 mg daily and will increase to standard dose. Spironolactone will be started at 50 mg daily and will increase to standard dose.

Group II: Daily sublingual estradiol plus spironolactoneActive Control5 Interventions

Starting dose will be 2 mg daily Plan to increase every month by 2 mg daily Goal is to achieve serum estradiol level between 100-200 pg/mL mL and to suppress testosterone to cisgender female levels. All patients will also receive spironolactone. Spironolactone will be started at 50 mg daily and will increase to standard dose. Spironolactone will be started at 50 mg daily and will increase to standard dose.

Group III: Transdermal estradiol plus spironolactoneActive Control5 Interventions

Starting dose will be 100 mcg/24hrs Plan to increase by 100 mcg/24hrs every month to a max dose of 400 mcg/24hrs Goal is to achieve a serum estradiol level between 100-200 pg/mL and to suppress testosterone to cisgender female levels All patients will also receive spironolactone. Spironolactone will be started at 50 mg daily and will increase to standard dose.

Do I qualify?Apply below to find out

Research Highlights

Information in this section is not a recommendation. We encourage patients to speak with their healthcare team when evaluating any treatment decision.

Mechanism Of Action

Side Effect Profile

Prior Approvals

Other Research

The most common treatments for transgender women include estrogen and antiandrogens. Estrogen works by inducing feminizing effects such as breast development, redistribution of body fat, and reduction of muscle mass. It also suppresses the production of testosterone, which is responsible for masculinizing features. Antiandrogens, such as spironolactone or cyproterone acetate, further inhibit the effects of testosterone by blocking androgen receptors or reducing androgen production. These treatments are crucial for transgender patients as they help align their physical appearance with their gender identity, thereby improving psychological well-being and quality of life.

Antiandrogen or estradiol treatment or both during hormone therapy in transitioning transgender women.

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Who is running the clinical trial?

Washington University School of MedicineLead Sponsor

1,945 Previous Clinical Trials

2,303,720 Total Patients Enrolled

Ginger Nicol, MDPrincipal InvestigatorWashington University School of Medicine

6 Previous Clinical Trials

309 Total Patients Enrolled

Media Library

Transgender Research Study Groups: Twice daily sublingual estradiol plus spironolactone, Daily sublingual estradiol plus spironolactone, Transdermal estradiol plus spironolactone

Transgender Clinical Trial 2023: Estradiol Highlights & Side Effects. Trial Name: NCT05010707 — Phase 2

~27 spots leftby Jun 2025

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