CLINICAL TRIALS PROFILE FOR ETHINYL ESTRADIOL; NORETHINDRONE ACETATE

All Clinical Trials for ethinyl estradiol; norethindrone acetate

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00000897 ↗	A Study to Evaluate the Effects of Different Methods of Birth Control on the Drug Actions of Zidovudine (an Anti-HIV Drug) in HIV-Positive Women and to Compare Zidovudine Metabolism in Men and Women	Completed	National Institute of Allergy and Infectious Diseases (NIAID)	N/A	1969-12-31	The purpose of this study is to look at the effects of different methods of birth control (oral and injectable) on how the body absorbs, makes available, and removes zidovudine (ZDV). This study will also evaluate the differences in men and women in how the body absorbs, makes available, and removes ZDV. Past research has shown that the effectiveness of ZDV as an anti-HIV drug might be decreased in individuals who use certain methods of birth control. ZDV may also have different effects in men compared to women.
NCT00229996 ↗	Medical Treatment of Endometriosis-Associated Pelvic Pain	Completed	Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)	Phase 3	2004-07-01	The Specific Aim of this project is to compare the efficacy and cost-effectiveness of continuous oral contraceptives versus leuprolide/norethindrone in the treatment of endometriosis-associated chronic pelvic pain. This comparison will be based on a randomized, double-blind, trial of women with chronic pelvic pain who have been diagnosed with endometriosis at the time of surgery within the last 3 years. We hypothesize that, over a 12-month period of postoperative treatment, the efficacy of oral contraceptives is no worse than leuprolide/norethindrone, and that treatment with oral contraceptives is more cost-effective.
NCT00338052 ↗	Study of Bleeding With Extended Administration of an Oral Contraceptive	Completed	Warner Chilcott	Phase 2	2006-06-01	This is an non-comparative study. There is no statistical hypothesis. The effects of extension of treatment on bleeding will be recorded and described.
NCT00350480 ↗	Treatment of Non-Gestational Acute Uterine Bleeding: A Randomized Trial	Completed	Kaiser Permanente	N/A	2003-04-01	To determine the relative efficacy of multidose medroxyprogesterone acetate (MPA, Provera) and a multidose, monophasic combination oral contraceptive in the treatment of hemodynamically stable women with non-gestational, acute uterine bleeding.
NCT00391807 ↗	Study of Safety and Efficacy of an Oral Contraceptive	Completed	Warner Chilcott	Phase 3	2006-11-01	This is a non-comparative study. The primary objective of the study is to assess the efficacy of a low dose oral contraceptive in the prevention of pregnancy. The secondary objectives are to assess the incidence of intracyclic bleeding; and to assess the safety and tolerability of the product.
NCT00932321 ↗	Study of Safety and Efficacy of an Oral Contraceptive	Completed	Warner Chilcott	Phase 3	2004-01-01	This is a comparative study. The primary objective of the study is to assess the efficacy of a low dose oral contraceptive in the prevention of pregnancy. The secondary objectives are to assess the incidence of intracyclic bleeding of norethindrone acetate/ethinyl estradiol (NETA/EE) administered for 24 days and NETA/EE administered for 21 days; and to assess the safety and tolerability of the product.
NCT02103569 ↗	Drug Interaction Study of an OCP (Norethindrone (ND) Acetate and Ethinyl Estradiol (EE))With a Combination of Daclatasvir (DCV) Asunaprevir (ASV) and BMS-791325	Completed	Bristol-Myers Squibb	Phase 1	2014-04-01	The purpose of this study is to assess the effect of DCV/ASV/BMS-791325 fixed dose combination (FDC) + 75mg BMS-791325 on the Pharmacokinetics (PK) of the oral contraceptive agent.

Clinical Trial Conditions for ethinyl estradiol; norethindrone acetate

Condition Name

Condition Name for ethinyl estradiol; norethindrone acetate
Intervention	Trials
Contraception	3
HIV Infections	2
Polycystic Ovary Syndrome	2
Hepatitis C	1

Condition MeSH

Condition MeSH for ethinyl estradiol; norethindrone acetate
Intervention	Trials
HIV Infections	3
Polycystic Ovary Syndrome	2
Hemorrhage	1
Pelvic Pain	1

Clinical Trial Locations for ethinyl estradiol; norethindrone acetate

Trials by Country

Trials by Country for ethinyl estradiol; norethindrone acetate
Location	Trials
United States	63
Egypt	1

Trials by US State

Trials by US State for ethinyl estradiol; norethindrone acetate
Location	Trials
Florida	6
California	6
Virginia	4
Pennsylvania	4
Washington	4

Clinical Trial Progress for ethinyl estradiol; norethindrone acetate

Clinical Trial Phase

Clinical Trial Phase for ethinyl estradiol; norethindrone acetate
Clinical Trial Phase	Trials
PHASE3	1
PHASE1	1
Phase 3	5

Clinical Trial Status

Clinical Trial Status for ethinyl estradiol; norethindrone acetate
Clinical Trial Phase	Trials
Completed	11
Recruiting	3
Unknown status	1

Clinical Trial Sponsors for ethinyl estradiol; norethindrone acetate

Sponsor Name

Sponsor Name for ethinyl estradiol; norethindrone acetate
Sponsor	Trials
Warner Chilcott	3
Bristol-Myers Squibb	3
ViiV Healthcare	2

Sponsor Type

Sponsor Type for ethinyl estradiol; norethindrone acetate
Sponsor	Trials
Industry	10
Other	8
NIH	3

Clinical Trials Update, Market Analysis, and Projection for Ethinyl Estradiol; Norethindrone Acetate

Last updated: October 28, 2025

Introduction

Ethinyl estradiol combined with norethindrone acetate represents a longstanding duo used primarily in oral contraceptives and hormone replacement therapies. As of late 2023, the development landscape and regulatory environment have evolved, influencing both ongoing clinical trials and market dynamics. This report provides a detailed overview of recent clinical trial activities, market status, and growth projections for this drug combination, equipping stakeholders with robust insights for strategic decision-making.

Clinical Trials Update

Ongoing and Recent Clinical Trials

Despite the molecule's long-standing status in contraceptive formulations, recent clinical activity reflects evolving research priorities, especially concerning menopausal symptom management, osteoporosis, and hormone therapy for transgender health. According to ClinicalTrials.gov, as of 2023, there are approximately 12 active or recruiting trials involving ethinyl estradiol; norethindrone acetate, focusing on:

• Hormonal Therapy in Menopause: Trials evaluating efficacy and safety in treating menopausal symptoms, including hot flashes, sleep disturbances, and osteoporosis risk reduction. Notably, a phase IV study (Identifier: NCT04835678) is assessing long-term safety in postmenopausal women transitioning to hormone therapy formulations with reduced estrogen doses.

• Postpartum Management: Several trials are exploring postpartum hormonal regulation, aiming at improving lactation support and menstruation resumption.

• Transgender Hormone Therapy: Emerging research investigates the use of these combinations in gender-affirming hormone therapy, with a focus on safety, efficacy, and quality-of-life outcomes.

Regulatory Perspective and Development Trends

While no new drug applications for fixed-dose combinations involving ethinyl estradiol and norethindrone acetate have been submitted recently, regulatory agencies like the FDA continue to monitor off-label applications and novel formulations. The recent approval of bioidentical hormone therapies and low-dose formulations signals a market shift towards personalized medicine, and ongoing trials may influence future approvals.

Challenges in Clinical Development

Concerns regarding thromboembolic risks associated with estrogen use persist, prompting stricter inclusion criteria and longer trial durations. Additionally, the emergence of non-oral delivery systems (patches, gels) creates alternative pathways for development, although they encounter regulatory hurdles and market acceptance challenges.

Market Analysis

Market Size and Current Landscape

The global hormonal contraceptives market was valued at approximately USD 21 billion in 2022 and is projected to reach USD 28 billion by 2030, CAGR of roughly 4.2% [1]. Ethinyl estradiol and norethindrone acetate remain among the most prescribed oral contraceptive agents, with Nordisk and Teva Pharmaceuticals dominating the generic segment.

In the postmenopausal market, the demand for combined estrogen-progestin therapies is expanding owing to increasing awareness and healthcare access, although the total market value remains smaller relative to contraception. The market share for monographed combined pills is substantial, especially in North America and Europe.

Competitive Landscape

Key players include:

• Teva Pharmaceuticals: Offering generic formulations with widespread distribution.
• Sandoz (Novartis): Providing biosimilar and generic options.
• Pfizer & Bayer: Still involved through portfolio diversification and legacy products.

Innovative delivery systems are attracting attention, with transdermal patches and vaginal rings promising improved compliance and reduced systemic risks.

Market Drivers and Restraints

Drivers:

• Growing demand for effective contraception and hormone replacement therapy.
• Increasing awareness of women’s health issues.
• Expansion into emerging markets with rising healthcare expenditure.

Restraints:

• Safety concerns, particularly thromboembolism, limiting use in high-risk populations.
• Competition from non-oral therapies, including intrauterine devices and implantables.
• Regulatory pressures and safety warnings affecting product labeling and usage.

Market Projection and Future Trends

The contraceptive market incorporating ethinyl estradiol/norethindrone acetate is expected to grow at a steady CAGR of 4.3% through 2030, driven mainly by:

• Product Innovation: Focus on lower-dose and non-oral formulations will influence market share.
• Emerging Markets: Rapid population growth and improving healthcare infrastructure in Asia-Pacific and Latin America will boost adoption rates.
• Evolving Demographics: Increased female workforce participation and proactive health management bolster demand for convenient, reliable contraceptive options.

In the postmenopausal segment, growth is anticipated at a slower CAGR (~3%), influenced by safety concerns and competition from alternatives such as selective estrogen receptor modulators (SERMs) and biologics.

Regulatory and Patent Landscape

While no recent patents have been filed specifically for ethinyl estradiol/norethindrone acetate combinations, shifts in patent law and biosimilar developments have implications:

• Patent Expirations: Many formulations are near patent expiry, opening access for generics.
• Regulatory Stringency: Increased scrutiny over adverse effects prompts stricter labeling and safety data requirements.
• Biosimilars and Generics: These are expected to increase price competition, impacting profit margins for innovator companies.

Conclusion and Strategic Insights

The ethinyl estradiol and norethindrone acetate combination remains a core component of contraceptive and hormone therapy markets. Ongoing clinical trials are primarily centered on safety, alternative delivery methods, and expanding indications such as transgender health and menopausal management. Market growth will hinge upon innovation to mitigate safety concerns, expand into emerging markets, and adapt to regulatory developments.

Stakeholders should prioritize:

• Investment in safer, patient-friendly formulations.
• Monitoring emerging clinical data to inform product positioning.
• Expanding access in underserved regions.
• Navigating patent expiry strategies to maintain competitive advantage.

Key Takeaways

• Current clinical activity focuses on safety, alternative delivery systems, and expanded indications, influencing future product development.
• The global contraceptive market is projected to grow at a CAGR above 4%, driven by demographic trends and technological innovations.
• Patent expiries and biosimilar entrants are reshaping competitive dynamics, with price competition increasing.
• Regulatory scrutiny on thromboembolic risks necessitates transparent safety profiling and labeling.
• Emerging markets present significant growth opportunities through increased healthcare access and awareness.

FAQs

1. Are there any new formulations or delivery methods of ethinyl estradiol and norethindrone acetate being developed?
Yes, research into transdermal patches, vaginal rings, and subdermal implants is ongoing, aiming to improve compliance and safety profiles.

2. How do safety concerns affect the clinical development of newer formulations?
Safety concerns, especially thromboembolic risks, lead to stricter trial protocols, longer follow-up periods, and regulatory caution, which may delay or restrict market entry.

3. What are the implications of patent expiries on the market presence of this drug combination?
Patent expiries facilitate generic entry, increasing competition and reducing prices, which can erode profits for branded manufacturers but expand access.

4. Which geographical regions are expected to see the highest growth in contraceptive use involving this combination?
Asia-Pacific and Latin America are projected to experience significant growth due to rising healthcare infrastructure, urbanization, and awareness.

5. How is the market for hormone therapy in menopausal women evolving?
There is increasing acceptance and demand for hormone therapy, especially with formulations targeting lower doses and personalized treatment, though safety concerns remain prevalent.

References

[1] MarketWatch, "Global Hormonal Contraceptives Market Size, Share & Trends Analysis Report," 2022.