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Tamoxifen Oral Tablet
Tamoxifen is a selective estrogen receptor modulator (SERM) that blocks estrogen binding to its receptor on breast cancer cells, inhibiting their growth.
Tamoxifen is a selective estrogen receptor modulator (SERM) that blocks estrogen binding to its receptor on breast cancer cells, inhibiting their growth. Used for Hormone receptor-positive breast cancer (adjuvant and metastatic), Breast cancer risk reduction in high-risk women, Ductal carcinoma in situ (DCIS).
At a glance
| Generic name | Tamoxifen Oral Tablet |
|---|---|
| Sponsor | Samsung Medical Center |
| Drug class | Selective estrogen receptor modulator (SERM) |
| Target | Estrogen receptor alpha (ERα) |
| Modality | Small molecule |
| Therapeutic area | Oncology |
| Phase | FDA-approved |
Mechanism of action
Tamoxifen competitively binds to estrogen receptors on hormone-responsive breast cancer cells, preventing endogenous estrogen from activating these receptors and promoting cell proliferation. This leads to cell cycle arrest and apoptosis in estrogen receptor-positive tumors. It also has partial agonist activity in some tissues, which accounts for its effects on bone and lipid metabolism.
Approved indications
- Hormone receptor-positive breast cancer (adjuvant and metastatic)
- Breast cancer risk reduction in high-risk women
- Ductal carcinoma in situ (DCIS)
Common side effects
- Hot flashes
- Vaginal discharge
- Nausea
- Vaginal bleeding
- Thromboembolic events
- Endometrial cancer
- Cataracts
Key clinical trials
- A Study of Elacestrant Versus Standard Endocrine Therapy in Women and Men With ER+,HER2-, Early Breast Cancer With High Risk of Recurrence (PHASE3)
- A Study of MK-5684 in People With Certain Solid Tumors (MK-5684-015/OMAHA-015) (PHASE2)
- A Study to Evaluate the Efficacy and Safety of Inavolisib in Combination With Phesgo Versus Placebo in Combination With Phesgo in Participants With PIK3CA-Mutated HER2-Positive Locally Advanced or Metastatic Breast Cancer (PHASE3)
- Phase 2 Study of Amcenestrant (SAR439859) Versus Physician's Choice in Locally Advanced or Metastatic ER-positive Breast Cancer (PHASE2)
- Assessing the Efficacy and Safety of Anti-HER2 Therapy in Nigerian Women With HER2+ Breast Cancer Before and After Surgery (PHASE2)
- Umbrella Trial of Subtype-Targeted Therapies in ER+/HER2- Breast Cancer (PHASE2)
- FLASH-Breast: Evaluating the Efficacy of Fezolinetant in Reducing Vasomotor Symptoms in Women With Breast Cancer on Endocrine Therapy (PHASE2)
- TRADE: Dose Escalation Tolerability of Abemaciclib in HR+ HER2- Early Stage Breast Cancer (PHASE2)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- Tamoxifen Oral Tablet CI brief — competitive landscape report
- Tamoxifen Oral Tablet updates RSS · CI watch RSS
- Samsung Medical Center portfolio CI