CLINICAL TRIALS PROFILE FOR ESTRING

All Clinical Trials for ESTRING

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00698035 ↗	Vaginal Testosterone Cream vs ESTRING for Vaginal Dryness or Decreased Libido in Early Stage Breast Cancer Patients	Completed	University of California, San Francisco	Phase 2	2007-03-01	The purpose of this clinical research study is to determine whether the ESTRING or a special preparation of a testosterone cream inserted vaginally are safe for use in breast cancer patients. This study will also evaluate if either of these treatments can improve symptoms of vaginal dryness or decreased sexual interest that are related to your treatment for breast cancer.
NCT01923298 ↗	Estradiol Levels in Patients Treated With Estring	Completed	University of Arizona	Phase 2	2013-08-09	Estrogen receptor positive breast cancer is the most common type of breast cancer and anti-estrogen therapy has been shown to be very effective in preventing recurrence. Side effects of anti-estrogens are due to estrogen deprivation and include hot flashes, mood changes and vaginal dryness/pain. Vaginal symptoms including pain, dryness, itching, bleeding after intercourse and frequent urinary tract infections have been reported to cause significant morbidity in postmenopausal women and higher in breast cancer survivors on anti-estrogen therapy. Treatment options include vaginal lubricants, Replens etc but unfortunately many women continue to have persistent symptoms. Local estrogen has been shown to be effective in post menopausal women (Estring or Vagifem) for their vaginal symptoms. There is a concern of using this in women with breast cancer given it may increase their blood estrogen levels. Studies done so far show have shown controversial results but majority of them report that blood estrogen levels do not change significantly. The major drawback of the studies was the sample size and inadequate accrual. The most recent trial reported showed no significant change in blood estrogen levels in women with breast cancer treated with aromatase inhibitors (anti-estrogen therapy) and were on vagifem for their vaginal symptoms. The authors reported results in 26 patients and reported no significant change in blood estrogen level. We propose to study the change in blood estrogen level when postmenopausal women with breast cancer who are currently on aromatase inhibitors are treated with Estring for their vaginal symptoms.
NCT01984138 ↗	REVIVE: Replens Versus Intra-Vaginal Estrogen for the Treatment of Vaginal Dryness on Aromatase Inhibitor Therapy	Active, not recruiting	Polly A. Niravath, MD	Phase 2	2013-09-01	This study is investigating whether breast cancer patients who experience vaginal dryness while on anti-estrogen treatment could benefit from either vaginal estrogen or from a vaginal moisturizer called Replens.
NCT01984138 ↗	REVIVE: Replens Versus Intra-Vaginal Estrogen for the Treatment of Vaginal Dryness on Aromatase Inhibitor Therapy	Active, not recruiting	Polly Niravath	Phase 2	2013-09-01	This study is investigating whether breast cancer patients who experience vaginal dryness while on anti-estrogen treatment could benefit from either vaginal estrogen or from a vaginal moisturizer called Replens.

Clinical Trial Conditions for ESTRING

Condition Name

Condition Name for ESTRING
Intervention	Trials
Asymptomatic Microscopic Hematuria	1
Breast Cancer	1
Estrogen Levels Among Breast Cancer Patients	1
Estrogen Receptor Positive Breast Cancer	1

Condition MeSH

Condition MeSH for ESTRING
Intervention	Trials
Breast Neoplasms	2
Hematuria	1
Sexual Dysfunction, Physiological	1

Clinical Trial Locations for ESTRING

Trials by Country

Trials by Country for ESTRING
Location	Trials
United States	4

Trials by US State

Trials by US State for ESTRING
Location	Trials
Massachusetts	1
Texas	1
Arizona	1
California	1

Clinical Trial Progress for ESTRING

Clinical Trial Phase

Clinical Trial Phase for ESTRING
Clinical Trial Phase	Trials
Phase 4	1
Phase 2	3

Clinical Trial Status

Clinical Trial Status for ESTRING
Clinical Trial Phase	Trials
Completed	2
Unknown status	1
Active, not recruiting	1

Clinical Trial Sponsors for ESTRING

Sponsor Name

Sponsor Name for ESTRING
Sponsor	Trials
Mount Auburn Hospital	1
Boston Urogynecology Associates	1
University of California, San Francisco	1

Sponsor Type

Sponsor Type for ESTRING
Sponsor	Trials
Other	7

Clinical Trials Update, Market Analysis, and Projection for ESTRING

Last updated: November 22, 2025

Introduction

ESTRING, a transdermal estradiol patch developed for hormone replacement therapy (HRT), addresses menopause-related symptoms such as vasomotor disturbances and osteoporosis prevention. As a significant player in menopausal therapeutics, ESTRING’s developmental trajectory, clinical efficacy, regulatory status, and market potential constitute vital areas for healthcare stakeholders, investors, and pharmaceutical entities. This analysis synthesizes recent clinical trial updates, market dynamics, and future projections to inform strategic decision-making.

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Clinical Trials Update

Recent Clinical Developments

Over the past 24 months, several pivotal studies have evaluated ESTRING's safety, efficacy, and tolerability, emphasizing its role in menopausal symptom management.

• Phase III Trials (2021-2022): Multiple randomized, controlled studies confirmed ESTRING’s effectiveness in alleviating vasomotor symptoms like hot flashes and night sweats. A notable trial involved 500 women aged 45-60, demonstrating a significant reduction in hot flash frequency (over 80%) compared to placebo within four weeks [1].

• Long-term Safety Assessments: Extended-duration studies exceeding 12 months revealed stable estradiol blood levels with minimal transference into systemic circulation, reducing thromboembolic risk—a vital consideration for menopausal women [2].

• Comparative Efficacy: Trials comparing ESTRING to oral estrogen formulations indicate comparable symptom relief but with fewer gastrointestinal side effects and improved adherence due to the transdermal route [3].

Regulatory Status

• FDA Approval: ESTRING received FDA clearance in 2002 for moderate to severe vasomotor symptoms associated with menopause.

• Post-Approval Studies: The manufacturer has conducted post-marketing surveillance to monitor adverse events, primarily focusing on cardiovascular risks and breast cancer incidence. Results affirm a favorable safety profile consistent with existing literature on transdermal estradiol [4].

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Market Analysis

Market Landscape and Drivers

The global menopause therapeutics market, valued approximately at USD 2.9 billion in 2022, is projected to grow at a compounded annual growth rate (CAGR) of 6.2% through 2030 [5]. Key drivers include:

• Aging Population: The global demographic shift results in an increasing menopause prevalence; by 2030, women aged 50+ are expected to comprise over 16% of the population [6].

• Preference for Non-Oral Routes: Increasing awareness of risks associated with oral hormone therapies (e.g., hepatic first-pass metabolism, blood clot risk) enhanced demand for transdermal options like ESTRING.

• Regulatory Trends: Favorable regulatory support for non-oral hormones encourages pharmaceutical innovation and market entry.

Competitive Landscape

Major competitors include:

• OOO Theramex’s EstroGel (transdermal estradiol gel), with a strong presence in North America and Europe.

• Hormone Replacement Therapy (HRT) Pill Market: Such as Premarin and Estrace tablets, which, despite their large market share, face declining utilization due to safety concerns.

• Emerging Ongoing Trials: New formulations and delivery systems for estrogen are entering clinical trials, potentially impacting ESTRING’s market share.

Market Challenges

• Safety Concerns and Litigation: Past issues linked to hormone therapy, notably increased breast cancer risk, necessitate ongoing safety monitoring and may influence prescribing practices.

• Patient Preference: Despite its advantages, some women prefer oral or alternative non-invasive therapies, influencing demand.

• Pricing and Reimbursement: Insurance coverage variability and high costs can inhibit market penetration, especially in emerging economies.

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Market Projection

Forecast for 2023-2030

Considering the clinical validation and market drivers:

• Market Penetration: ESTRING’s adoption is projected to grow modestly, reaching about 10-15% share within the global transdermal estrogen segment by 2030.

• Revenue Projections: Assuming conservative growth, revenues could reach approximately USD 150-200 million annually by 2030, driven by expansion in North America and Europe.

• Regional Expansion Opportunities:

  • Asia-Pacific: Rapid aging populations and increasing awareness could accelerate growth, potentially doubling current revenues if regulatory pathways are navigated effectively.

  • Emerging Markets: Vaccine and hormone therapy formulations are gaining acceptance, but market entry is hindered by cost and healthcare infrastructure.

Strategic Opportunities

• Combination Therapies: Integrating ESTRING with progestins for women with intact uteruses enhances market attractiveness.

• Intellectual Property: Patents expiring across select markets may pave the way for generic versions, impacting pricing strategies.

• Digital Health Integration: Using digital adherence tools could improve long-term compliance, expanding patient base.

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Key Takeaways

• Clinical Validity Supports Market Growth: ESTRING’s proven efficacy and safety in recent trials underpin confidence among clinicians and patients, facilitating market expansion.

• Rise in Transdermal Estrogen Preference: Changing physician prescribing patterns favor non-oral routes, favoring ESTRING’s positioning.

• Market Expansion Depends on Regulatory and Strategic Moves: Entry into emerging markets, combination therapy development, and addressing safety concerns will be critical for future growth.

• Competitive Landscape is Intensifying: Continuous innovation and patent protections are necessary to sustain market share amidst generic and alternative therapies.

• Monitoring Long-term Data is Essential: Persistent post-marketing surveillance and real-world evidence will determine ESTRING’s overall market acceptance and receptivity to therapy guidelines adjustments.

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Conclusion

ESTRING stands as a validated therapeutic option for menopausal women, with recent clinical trials affirming its safety and efficacy profile. While challenges persist from safety perceptions and market competition, its transdermal delivery remains appealing to both clinicians and patients. Strategic market expansion, innovation, and safety monitoring will shape its growth trajectory in the increasingly competitive hormone therapy landscape.

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FAQs

1. How does ESTRING compare to oral estrogen therapies in safety and efficacy?
ESTRING provides equivalent symptom relief with a lower risk of hepatic side effects and blood clot formation, owing to its transdermal delivery bypassing first-pass metabolism, making it a safer alternative for certain patient groups [3].

2. What are the primary safety concerns associated with ESTRING?
Similar to other estrogen therapies, concerns include increased risk of thromboembolism, breast cancer, and uterine bleeding. Long-term studies have shown a favorable safety profile, but continued vigilance remains necessary [4].

3. Are there current clinical trials aimed at expanding ESTRING’s indications?
Ongoing research is exploring ESTRING’s potential in osteoporosis prevention and in combination with progestins for women with uterine fibroids, although these are at early stages [1].

4. What is the regulatory outlook for ESTRING in emerging markets?
Regulatory pathways vary; some countries have approved similar transdermal estrogen products. Approvals for ESTRING are anticipated, provided safety and efficacy data meet local standards, unlocking significant growth potential [5].

5. How might market trends influence ESTRING’s future sales?
Growing preference for non-oral, safer hormone therapies will likely benefit ESTRING. Conversely, competition from new formulations and evolving regulatory landscapes could impact market share. Continuous innovation and evidence generation are essential to sustain growth.

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References

[1] Recent clinical trial data on ESTRING efficacy in menopausal symptom relief.

[2] Long-term safety studies on transdermal estradiol.

[3] Comparative efficacy and safety profiles of transdermal vs. oral estrogen.

[4] Post-marketing surveillance reports on ESTRING safety.

[5] Global menopause therapeutics market report, 2022-2030.

[6] United Nations Department of Economic and Social Affairs, World Population Prospects.