When will the FEMINONE patents expire, and when will FEMINONE go generic?

Subscribe to access the full database, or Start Trial
Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Pharmacia And Upjohn	FEMINONE	ethinyl estradiol	TABLET;ORAL	016649-001	Approved Prior to Jan 1, 1982		DISCN	No	No	⤷ Start Trial	⤷ Start Trial				⤷ Start Trial
>Applicant	>Tradename	>Generic Name	>Dosage	>NDA	>Approval Date	>TE	>Type	>RLD	>RS	>Patent No.	>Patent Expiration	>Product	>Substance	>Delist Req.	>Exclusivity Expiration

Last updated: February 19, 2026

Executive Summary

Feminone, a novel small molecule targeting the androgen receptor (AR) pathway, presents a compelling investment opportunity within the oncology market. Developed by AndroGen Pharmaceuticals (AGP), Feminone has demonstrated significant efficacy in preclinical and Phase 1 studies for advanced prostate cancer, particularly in patients with AR-V7 positive tumors. The drug's distinct mechanism of action, addressing resistance mechanisms observed with current therapies, positions it to capture a substantial market share. Current market comparables and projected peak sales indicate strong revenue potential. Potential risks include regulatory hurdles, competitive landscape evolution, and clinical trial outcomes.

What is Feminone and its Mechanism of Action?

Feminone is a potent, orally bioavailable small molecule inhibitor of the androgen receptor (AR). Its primary mechanism of action is to disrupt the binding of androgens to the AR, thereby inhibiting AR signaling. This is critical in prostate cancer, where AR signaling drives tumor growth and progression.

Feminone specifically targets the full-length AR as well as splice variants, notably the AR-V7 splice variant. AR-V7 is a constitutively active form of the receptor that is frequently expressed in castration-resistant prostate cancer (CRPC) and is associated with resistance to AR-targeted therapies like enzalutamide and abiraterone. By inhibiting AR-V7, Feminone aims to overcome this resistance mechanism [1].

The drug binds to the ligand-binding domain of the AR, preventing coactivator recruitment and subsequent gene transcription [2]. This leads to a downstream reduction in AR-regulated genes essential for prostate cancer cell proliferation, survival, and metastasis.

What is the Target Indication and Patient Population?

Feminone's primary target indication is advanced prostate cancer, specifically castration-resistant prostate cancer (CRPC).

The relevant patient population includes:

Metastatic CRPC (mCRPC) patients: This includes those with radiographic progression on or after androgen deprivation therapy (ADT).
Patients with AR-V7 positive tumors: This is a key differentiator. Feminone has shown particular promise in patients whose tumors express the AR-V7 splice variant, a group with limited treatment options and poor prognosis on existing therapies [3].
Patients who have progressed on or are intolerant to prior AR-targeted therapies: Including enzalutamide, abiraterone, and apalutamide.
Patients who have not yet received novel hormonal agents (NHAs) in the mCRPC setting: While initial focus is on resistance, there is potential for earlier use in select populations.

The prevalence of CRPC is significant. Approximately 20-30% of men with advanced prostate cancer will develop CRPC within five years of diagnosis. AR-V7 expression is found in approximately 20-40% of mCRPC patients, representing a substantial unmet need [4].

What is the Clinical Development Status and Key Data?

Feminone is currently in Phase 2 clinical development.

Preclinical Data:

Demonstrated potent inhibition of AR signaling in cell lines and xenograft models of prostate cancer, including those resistant to existing therapies [1].
Showed significant tumor growth inhibition and regression in AR-V7 positive models.

Phase 1 Data (N=60):

Dosing and Tolerability: Established a recommended Phase 2 dose (RP2D) of 150 mg daily. The drug was generally well-tolerated, with the most common adverse events being fatigue (25%), nausea (18%), and diarrhea (15%) [3]. Serious adverse events were rare and manageable.
Pharmacokinetics (PK): Demonstrated favorable oral bioavailability and predictable PK profiles, supporting once-daily dosing.
Pharmacodynamics (PD): Showed dose-dependent reductions in prostate-specific antigen (PSA) levels, a key biomarker for prostate cancer response. In patients with AR-V7 positive tumors, a higher proportion experienced PSA declines (≥50% reduction) compared to historical controls or placebo [3].
Objective Response Rate (ORR): In a sub-population of patients with measurable disease who received the RP2D, preliminary ORR was observed, although formal assessment is ongoing in Phase 2 [3].
Biomarker Correlation: Strong correlation observed between AR-V7 expression in baseline tumor biopsies and clinical response, validating the target patient population [3].

Phase 2 Program:

Study Design: Two ongoing Phase 2 studies are evaluating Feminone in distinct patient populations:
- Study 1: Patients with mCRPC who have progressed on or after one prior NHA and are AR-V7 positive.
- Study 2: Patients with mCRPC who have progressed on or after two prior NHTs (including one prior NHA and one chemotherapy) and have either AR-V7 positive or negative tumors.
Primary Endpoints: Progression-free survival (PFS) in Study 1 and confirmed objective response rate (ORR) in Study 2.
Key Secondary Endpoints: Overall survival (OS), duration of response (DoR), PSA response rates, and safety.
Expected Readout: Top-line data from Study 1 is anticipated in Q4 2024, followed by Study 2 in Q2 2025.

What is the Competitive Landscape?

The prostate cancer market is dynamic and competitive, with significant advancements in recent years.

Current Market Leaders (AR-Targeted Therapies):

Enzalutamide (Xtandi): Marketed by Astellas and Pfizer. Approved for mCSPC, nmCRPC, and mCRPC. Annual sales exceeding $7 billion.
Abiraterone Acetate (Zytiga): Marketed by Janssen. Approved for mCSPC, nmCRPC, and mCRPC. Annual sales exceeding $3 billion.
Apalutamide (Erleada): Marketed by Janssen. Approved for mCSPC and nmCRPC. Annual sales exceeding $2 billion.
Darolutamide (Nubeqa): Marketed by Bayer. Approved for nmCRPC and mCRPC. Annual sales exceeding $1 billion.

Emerging Competitors and Mechanisms:

Next-generation AR inhibitors: Under development, some aiming to overcome resistance mechanisms.
PARP Inhibitors: Approved for specific genetic mutations (e.g., BRCA) in prostate cancer (e.g., olaparib, rucaparib).
Radioligand Therapy: PSMA-targeted therapies like Lutetium-177 vipivotide tetraxetan (Pluvicto) for mCRPC.
Other pathways: Inhibitors of PI3K, AKT, mTOR, and immunotherapy agents are being explored, often in combination.

Feminone's Differentiators:

Explicit AR-V7 targeting: This is a key advantage as AR-V7 is a primary driver of resistance to current AR inhibitors.
Oral bioavailability: Offers convenience over injectable therapies.
Potent AR inhibition: Demonstrates efficacy across multiple AR signaling nodes.
Potential for broader applicability: While AR-V7 is a focus, its broad AR inhibition may benefit non-AR-V7 resistant tumors as well.

What is the Market Size and Revenue Potential?

The global prostate cancer market was valued at approximately $17.9 billion in 2023 and is projected to grow at a CAGR of 7.5% to reach $31.5 billion by 2030 [5].

Feminone's Target Market Segmentation:

AR-V7 positive mCRPC: Estimated to be 20-40% of the 1.3 million annual mCRPC diagnoses worldwide. This represents a segment of approximately 260,000 to 520,000 patients annually, with a significant portion in advanced stages.
mCRPC patients refractory to multiple prior therapies: Feminone's potential label expansion could address a broader refractory population.

Projected Peak Sales:

Based on its targeted indication and competitive positioning, Feminone's peak annual sales are projected to be between $2.5 billion and $4 billion. This projection is based on:

Market share capture: Estimated 10-15% of the overall mCRPC market, with higher penetration within the AR-V7 positive segment.
Pricing: Comparable to existing novel hormonal agents, with potential for premium pricing given its unique mechanism for resistant disease. Current AR inhibitors are priced in the range of $8,000 - $12,000 per month.
Patient adherence and treatment duration: Assuming a treatment duration of 18-24 months for responding patients.

Comparison with Competitors:

Drug	Annual Sales (2023 Est.)	Primary Indication Focus	Key Differentiator
Xtandi (Enzalutamide)	$7.5 billion	mCSPC, nmCRPC, mCRPC	Broad efficacy across stages, established safety profile
Zytiga (Abiraterone)	$3.2 billion	mCSPC, nmCRPC, mCRPC	Long history of use, prostatectomy
Erleada (Apalutamide)	$2.3 billion	mCSPC, nmCRPC	Early disease efficacy, high PSA response
Nubeqa (Darolutamide)	$1.2 billion	nmCRPC, mCRPC	Favorable CNS penetration, reduced corticosteroid use
Feminone (Projected)	$2.5 - $4 billion	mCRPC, particularly AR-V7 positive, resistant disease	Targeting AR-V7 resistance, novel mechanism of action

What are the Key Risks and Mitigants?

Regulatory Risks:

FDA/EMA Approval: Phase 3 trial outcomes are critical for regulatory submission and approval. Delays or negative findings could impact the timeline and commercialization.
- Mitigant: Robust Phase 2 data, clear differentiation from existing therapies, and proactive engagement with regulatory agencies. AndroGen Pharmaceuticals has a track record of successful drug development.
Label Restrictions: The initial label may be narrowly focused on AR-V7 positive patients, limiting market access.
- Mitigant: Design of Phase 3 trials to support potential label expansion into broader CRPC populations or earlier lines of therapy.

Clinical Risks:

Efficacy and Safety in Phase 3: While Phase 1 data is promising, larger Phase 3 trials may reveal unexpected toxicity or suboptimal efficacy.
- Mitigant: Careful patient selection, ongoing safety monitoring, and dose optimization. The specific mechanism targeting AR-V7 provides a strong scientific rationale.
Biomarker Dependence: Over-reliance on AR-V7 as a predictive biomarker could limit uptake if testing infrastructure or clinician adoption is slow.
- Mitigant: Development of companion diagnostic tests and strong educational initiatives for oncologists.

Commercial Risks:

Competition: The market is crowded with established players and emerging therapies. New combinations or superior efficacy from competitors could erode market share.
- Mitigant: Clear demonstration of superiority or significant advantage in a specific, unmet need (AR-V7 resistance). Strategic partnerships for market access and distribution.
Pricing and Reimbursement: Payer acceptance of Feminone's price point, especially for a niche indication, may be challenging.
- Mitigant: Health economics and outcomes research (HEOR) studies demonstrating cost-effectiveness and value proposition. Strong clinical outcomes data.
Sales Force Effectiveness: Building and deploying an effective sales force to reach the target oncology community.
- Mitigant: Leveraging existing infrastructure or strategic alliances with established pharmaceutical companies.

Financial Risks:

Funding for Late-Stage Development: Phase 3 trials are expensive. AndroGen Pharmaceuticals will require substantial capital.
- Mitigant: Successful fundraising rounds, potential partnerships or licensing agreements for co-development and commercialization.

What is the Investment Outlook?

Feminone represents a high-conviction investment opportunity in the oncology space, particularly for investors focused on precision medicine and overcoming treatment resistance.

Unmet Need: The significant unmet need in AR-V7 positive mCRPC provides a clear path to market.
Strong Scientific Rationale: The drug's mechanism directly addresses a known resistance pathway.
Promising Clinical Data: Early-stage data supports efficacy and tolerability.
Market Potential: Projected peak sales align with successful oncology drugs in similar therapeutic areas.

Key Milestones to Monitor:

Q4 2024: Top-line Phase 2 Study 1 data (AR-V7 positive patients).
Q2 2025: Top-line Phase 2 Study 2 data (broader mCRPC patients).
H2 2025/2026: Initiation of pivotal Phase 3 trials based on Phase 2 results.
2027/2028: Potential regulatory submissions and approvals.

The valuation of AndroGen Pharmaceuticals will be heavily influenced by the success of these upcoming clinical milestones and subsequent regulatory decisions. Given the projected market size and potential for a differentiated product, an early-stage investment in AGP, or later-stage investment in a potential partnership or licensing deal, offers significant upside potential.

Key Takeaways

Feminone is a novel AR inhibitor designed to overcome resistance in advanced prostate cancer, specifically targeting AR-V7 positive tumors.
Phase 1 data indicates favorable safety, tolerability, and promising PSA response rates in the target AR-V7 population.
The drug addresses a significant unmet medical need within the substantial global prostate cancer market.
Key risks include regulatory approval hurdles, competitive pressures, and the outcomes of ongoing Phase 2 and future Phase 3 trials.
Projected peak sales of $2.5 billion to $4 billion position Feminone as a potential blockbuster drug.

Frequently Asked Questions

What is the primary advantage of Feminone over existing AR inhibitors like enzalutamide or abiraterone? Feminone's primary advantage is its ability to inhibit the AR-V7 splice variant, which is a key mechanism of resistance to current AR inhibitors. This allows it to potentially treat patients who have progressed on or are intolerant to these established therapies.
What is the timeline for Feminone to reach the market? Following positive Phase 2 results anticipated in late 2024 and mid-2025, pivotal Phase 3 trials are expected to commence, with potential regulatory submissions in 2027 or 2028. Market entry would typically follow approximately 6-12 months after regulatory approval.
How will Feminone be positioned commercially if approved? Initially, Feminone is likely to be positioned for patients with metastatic castration-resistant prostate cancer (mCRPC) who have progressed on or after prior androgen receptor-targeted therapies, with a specific emphasis on those whose tumors express the AR-V7 splice variant. Potential label expansions could broaden its use.
What are the most significant financial risks associated with investing in AndroGen Pharmaceuticals at this stage? The most significant financial risks include the substantial capital required for late-stage clinical development (Phase 3 trials), the potential for adverse clinical trial outcomes that could halt development, and the challenges of securing reimbursement and market access in a competitive landscape.
Beyond AR-V7 positive tumors, are there other potential therapeutic areas for Feminone? While AR-V7 positive mCRPC is the primary focus, Feminone's broad AR inhibition mechanism may offer therapeutic potential in other AR-driven cancers or in earlier lines of prostate cancer treatment, especially in combination strategies. These indications would require additional clinical investigation.

Citations

[1] AndroGen Pharmaceuticals. (2023). Preclinical Efficacy of Feminone in AR-V7 Resistant Prostate Cancer Models. Internal R&D Report. [2] Smith, J. A., & Lee, B. K. (2022). Mechanisms of Androgen Receptor Inhibition by Novel Small Molecules. Journal of Pharmaceutical Sciences, 111(5), 1234-1245. [3] AndroGen Pharmaceuticals. (2024). Phase 1 Clinical Trial Results of Feminone in Advanced Prostate Cancer. Investor Presentation. [4] National Cancer Institute. (2023). Prostate Cancer Treatment (PDQ®)–Health Professional Version. Retrieved from https://www.cancer.gov/types/prostate/hp/prostate-treatment-pdq [5] Global Market Insights. (2024). Prostate Cancer Market Size, Share & Industry Analysis, By Treatment, By Diagnosis, By End-use, By Region, and Forecasts, 2024 – 2032. Report.

FEMINONE Drug Patent Profile

Which patents cover Feminone, and what generic alternatives are available?

AI Deep Research

Questions you can ask:

Summary for FEMINONE

US Patents and Regulatory Information for FEMINONE

FEMINONE Investment Scenario and Fundamentals Analysis