CLINICAL TRIALS PROFILE FOR TAMOXIFEN CITRATE

All Clinical Trials for TAMOXIFEN CITRATE

Trial ID	Title	Status	Sponsor	Phase	Start Date	Summary
NCT00002460 ↗	Adjuvant Hormone Therapy in Treating Women With Operable Breast Cancer	Unknown status	Cancer Research UK	Phase 3	1987-09-01	RATIONALE: Estrogen can stimulate the growth of breast cancer cells. Hormone therapy using tamoxifen may fight breast cancer by blocking the uptake of estrogen. PURPOSE: Phase III trial to compare the effectiveness of adjuvant therapy using tamoxifen or ovarian ablation with goserelin or both in treating women with stage I or stage II breast cancer.
NCT00002528 ↗	Surgery With or Without Lymph Node Removal in Treating Older Women With Stage I or Stage IIA Breast Cancer	Completed	International Breast Cancer Study Group	Phase 3	1993-05-01	RATIONALE: Removing axillary lymph nodes may be effective in stopping the spread of breast cancer cells. It is not yet known if surgery to remove breast cancer is more effective with or without lymph node removal. PURPOSE: Randomized phase III trial to compare the effectiveness of breast surgery with or without removal of axillary lymph nodes in treating women who have stage I or stage IIA breast cancer.
NCT00002529 ↗	Hormone Therapy and Chemotherapy in Treating Perimenopausal or Postmenopausal Women With Node-Positive Breast Cancer	Completed	International Breast Cancer Study Group	Phase 3	1993-05-01	RATIONALE: Estrogen can stimulate the growth of breast cancer cells. Hormone therapy may fight breast cancer by blocking the uptake of estrogen. Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. Combining chemotherapy with hormone therapy may kill more tumor cells. It is not yet known which treatment regimen is more effective for breast cancer. PURPOSE: Randomized phase III trial to compare the effectiveness of hormone therapy during or after combination chemotherapy or hormone therapy alone in treating perimenopausal or postmenopausal women who have stage II or stage IIIA breast cancer.
NCT00002542 ↗	Tamoxifen in Treating Women With High-Risk Breast Cancer	Completed	NCIC Clinical Trials Group	Phase 3	1993-07-20	RATIONALE: Estrogen can stimulate the growth of breast cancer cells. Hormone therapy using tamoxifen may fight breast cancer by blocking the uptake of estrogen. Chemotherapy uses different ways to stop tumor cells from dividing so they stop growing or die. PURPOSE: Phase III trial to study the effectiveness of tamoxifen following surgery and chemotherapy in treating women who have stage I breast cancer at high risk of recurrence or stage II or stage III breast cancer.
NCT00002579 ↗	Tamoxifen Following Combination Chemotherapy in Treating Women With Operable Invasive Breast Cancer	Completed	Scottish Cancer Therapy Network	Phase 3	1993-03-01	RATIONALE: Estrogen can stimulate the growth of breast cancer cells. Hormone therapy using tamoxifen may fight breast cancer by blocking the uptake of estrogen. Combining combination chemotherapy with hormone therapy may kill more tumor cells. PURPOSE: Randomized phase III trial to compare the effectiveness of combination chemotherapy with or without tamoxifen in treating women with stage I or stage II breast cancer that can be surgically removed.
NCT00002580 ↗	Tamoxifen, Ovarian Ablation, and/or Combination Chemotherapy in Treating Premenopausal Women With Stage I, Stage II, or Stage IIIA Invasive Breast Cancer	Completed	Scottish Cancer Therapy Network	Phase 3	1993-06-01	RATIONALE: Estrogen can stimulate the growth of breast cancer cells. Hormone therapy using tamoxifen may fight breast cancer by blocking the uptake of estrogen. Chemotherapy uses different ways to stop tumor cells from dividing so they stop growing or die. Combining chemotherapy with hormone therapy may kill more tumor cells. It is not yet known which treatment regimen is most effective for breast cancer. PURPOSE: Randomized phase III trial to compare the effectiveness of tamoxifen with that of ovarian ablation, and/or combination chemotherapy in treating premenopausal women with stage I, stage II, or stage IIIA breast cancer.
NCT00002581 ↗	Tamoxifen With or Without Combination Chemotherapy in Treating Postmenopausal Women With Operable Invasive Breast Cancer	Completed	Scottish Cancer Therapy Network	Phase 3	1993-06-01	RATIONALE: Estrogen can stimulate the growth of breast cancer cells. Hormone therapy using tamoxifen may fight breast cancer by blocking the uptake of estrogen. Combining combination chemotherapy with hormone therapy may kill more tumor cells. PURPOSE: Randomized phase III trial to compare the effectiveness of tamoxifen with or without combination chemotherapy in treating postmenopausal women with stage I or stage II breast cancer that can be surgically removed.

Clinical Trial Conditions for TAMOXIFEN CITRATE

Condition Name

Condition Name for TAMOXIFEN CITRATE
Intervention	Trials
Breast Cancer	79
Stage IIIB Breast Cancer	9
Stage IIIA Breast Cancer	8
Stage IV Breast Cancer	6

Condition MeSH

Condition MeSH for TAMOXIFEN CITRATE
Intervention	Trials
Breast Neoplasms	92
Carcinoma	14
Carcinoma in Situ	11
Carcinoma, Intraductal, Noninfiltrating	8

Clinical Trial Locations for TAMOXIFEN CITRATE

Trials by Country

Trials by Country for TAMOXIFEN CITRATE
Location	Trials
United States	887
Canada	86
United Kingdom	61
Australia	21
China	21

Trials by US State

Trials by US State for TAMOXIFEN CITRATE
Location	Trials
California	31
Illinois	26
Maryland	24
Minnesota	24
Texas	24

Clinical Trial Progress for TAMOXIFEN CITRATE

Clinical Trial Phase

Clinical Trial Phase for TAMOXIFEN CITRATE
Clinical Trial Phase	Trials
PHASE3	1
PHASE2	1
Phase 4	4

Clinical Trial Status

Clinical Trial Status for TAMOXIFEN CITRATE
Clinical Trial Phase	Trials
Completed	66
Unknown status	25
Active, not recruiting	17

Clinical Trial Sponsors for TAMOXIFEN CITRATE

Sponsor Name

Sponsor Name for TAMOXIFEN CITRATE
Sponsor	Trials
National Cancer Institute (NCI)	59
Southwest Oncology Group	11
Cancer and Leukemia Group B	9

Sponsor Type

Sponsor Type for TAMOXIFEN CITRATE
Sponsor	Trials
Other	217
NIH	59
Industry	13

Tamoxifen Citrate: Clinical Trials Update and Market Analysis with Forecast

Last updated: April 28, 2026

What is tamoxifen citrate and what is its clinical role?

Tamoxifen citrate is a selective estrogen receptor modulator (SERM) used across hormone receptor-positive breast cancer and related risk-reduction and treatment settings. The drug’s value proposition in current oncology practice is established: oral dosing, long-standing clinical evidence base, and broad guideline coverage for ER-positive disease, including adjuvant and prevention use.

Core clinical endpoints across tamoxifen use include:

• Disease-free survival (DFS) and overall survival (OS) in adjuvant settings
• Recurrence risk reduction in early breast cancer
• Invasive breast cancer risk reduction in higher-risk women
• Response outcomes in metastatic or advanced ER-positive disease (ORR, time-to-progression, OS)

What is the current clinical trials status for tamoxifen citrate?

A full “live trial-by-trial” update cannot be produced from the data available in this workspace because there is no trial registry dataset provided for retrieval, no trial identifiers, and no latest enrollment status or results tables supplied. Under the operational constraints, a complete and accurate response cannot be generated.

What market does tamoxifen citrate serve today?

Tamoxifen’s market is defined by:

• Breast cancer treatment segments: adjuvant and metastatic ER-positive disease
• Breast cancer prevention: reduction of invasive breast cancer risk in eligible high-risk populations
• Geography: high-burden regions plus markets with mature oncology guideline adherence

The market shape is influenced by:

• Long product lifespan and generic penetration in major markets
• Competition from aromatase inhibitors in postmenopausal adjuvant settings
• Switching behavior driven by menopausal status, tolerability, and contraindications

What does the competitive landscape look like?

Tamoxifen is an oral generic-heavy asset in most markets, with pricing and procurement models centered on:

• Wholesale acquisition cost (WAC) and payer reimbursement
• Formulation and supply availability
• Institutional tendering and pharmacy benefit design
• Clinician preference tied to menopausal status and risk profile

Key competitive substitutes depend on indication:

• Aromatase inhibitors (postmenopausal adjuvant)
• SERDs/SERMs and other endocrine agents where specific regimens are prioritized
• Surgery and radiation combinations in early disease, where endocrine therapy is one component

What are the demand drivers and constraints?

Demand drivers:

• Large prevalence of ER-positive breast cancer
• Guideline-backed adjuvant endocrine therapy use
• Prevention use in defined high-risk groups

Constraints:

• Patent expiry and widespread generics, compressing revenue per unit
• Therapy sequencing and guideline shifts favoring aromatase inhibitors in postmenopausal populations
• Safety and tolerability management affecting adherence and switching (vasomotor symptoms, thromboembolic events, endometrial risk monitoring)

How should investors and R&D teams think about future growth?

For tamoxifen citrate, growth is less about breakthrough clinical differentiation and more about:

• Market share stability vs generics and supply
• Indication-specific uptake where tamoxifen remains preferred or necessary
• Utilization patterns in oncology pathways for ER-positive disease and prevention

A credible projection requires current-year market size, unit volume, pricing trends, and regimen mix. Those inputs are not available in the provided material, so a numeric forecast cannot be produced without violating the completeness requirement.

Can tamoxifen citrate generate new differentiation through clinical development?

Tamoxifen’s development strategy typically targets:

• Optimization of dose, duration, and combination regimens
• Special populations (e.g., risk reduction cohorts, adherence, tolerability profiles)
• New formulations or pharmacokinetic improvements where justified

However, without registry-level trial data and results publication status, no accurate “clinical trials update” can be compiled.

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Market projection framework (how tamoxifen value is likely to move)

Even without a numeric forecast, a decision-grade framework for projection can be stated at the driver level:

1) Volume outlook

• Endocrine therapy uptake depends on incidence and staging patterns
• Prevention programs fluctuate with risk-model adoption and guideline emphasis
• Real-world adherence affects treated patient counts and persistence

2) Pricing outlook

• Generic pricing follows tender cycles, supply balance, and reimbursement structures
• Revenue growth is usually limited to incremental unit demand, not price expansion

3) Mix outlook

• Menopausal status mix drives choice between tamoxifen and aromatase inhibitors
• Line of therapy mix affects persistence and switching rates

4) Regulatory and safety outlook

• Labeling changes and risk management protocols influence clinician behavior
• Safety monitoring intensity affects continuation rates

5) Competitive displacement

• New endocrine options may reduce tamoxifen use in certain pathways
• Local formularies can preserve tamoxifen share or accelerate displacement

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Key Takeaways

• Tamoxifen citrate is an established SERM for ER-positive breast cancer and breast cancer risk reduction, with demand driven by guideline use and disease prevalence.
• A complete, accurate “clinical trials update” and a numeric market projection cannot be produced from the information available in this workspace.
• Near-term value for tamoxifen is structurally shaped by generic pricing, payer procurement, therapy-mix shifts against aromatase inhibitors, and safety management affecting adherence.

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FAQs

1. Is tamoxifen still used in current breast cancer standard of care?
   Yes, it is still used for ER-positive breast cancer, including adjuvant therapy and other guideline-supported endocrine settings.

2. What substitutes compete most directly with tamoxifen?
   Aromatase inhibitors in postmenopausal adjuvant therapy pathways, along with other endocrine agents depending on line of therapy and eligibility.

3. Why does generic penetration matter for tamoxifen market outlook?
   Generic availability compresses pricing and shifts competition toward procurement, supply reliability, and formulary access rather than innovation-led premium pricing.

4. What endpoints matter most in tamoxifen studies?
   DFS, OS, recurrence risk reduction, and response measures in advanced disease settings.

5. What are the main clinical constraints impacting utilization?
   Safety and tolerability monitoring, including thromboembolic risk considerations and endometrial risk management, which can affect persistence.

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References

[1] US Food and Drug Administration. Nolvadex (tamoxifen citrate) prescribing information (latest available labeled content).
[2] National Cancer Institute. Tamoxifen and breast cancer treatment/risk reduction information (clinical overview).
[3] EMA. Tamoxifen-containing medicines: EPAR and product information for authorized indications (regulatory product information).