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tamoxifen citrate (Tamoxifen)
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 (HR+) breast cancer, adjuvant treatment, Metastatic breast cancer, HR+, Breast cancer risk reduction in high-risk women.
At a glance
| Generic name | tamoxifen citrate (Tamoxifen) |
|---|---|
| Also known as | Nolvadex, Tam, Tamoxifen |
| Sponsor | H. Lee Moffitt Cancer Center and Research Institute |
| 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 (ER) on hormone-responsive breast cancer cells, preventing endogenous estrogen from activating these receptors and promoting cell proliferation. In estrogen receptor-positive breast cancers, this blockade halts cell division and can induce apoptosis. Tamoxifen also has partial agonist activity in some tissues, which accounts for its effects on bone density and thromboembolic risk.
Approved indications
- Hormone receptor-positive (HR+) breast cancer, adjuvant treatment
- Metastatic breast cancer, HR+
- Breast cancer risk reduction in high-risk women
- Ductal carcinoma in situ (DCIS)
Common side effects
- Hot flashes
- Vaginal discharge
- Nausea
- Venous thromboembolism (DVT/PE)
- Endometrial cancer
- Vaginal bleeding
- Fatigue
- Mood changes/depression
Key clinical trials
- Acolbifene Versus Low Dose Tamoxifen for the Prevention of Breast Cancer in Premenopausal Women at High Risk for Development of Breast Cancer (PHASE2)
- Finding the Best Tamoxifen Dose for Breast Cancer Risk Reduction in Premenopausal Women, RENAISSANCE Trial (PHASE2)
- Drug Repurposing in Thyroid Carcinoma: a Feasibility Trial (PHASE1)
- Tamoxifen Citrate or Z-Endoxifen Hydrochloride in Treating Patients With Locally Advanced or Metastatic, Estrogen Receptor-Positive, HER2-Negative Breast Cancer (PHASE2)
- A Study of Elacestrant Versus Standard Endocrine Therapy in Women and Men With ER+,HER2-, Early Breast Cancer With High Risk of Recurrence (PHASE3)
- Letrozole After Tamoxifen in Treating Women With Breast Cancer (PHASE3)
- Hormone Therapy With or Without Combination Chemotherapy in Treating Women Who Have Undergone Surgery for Node-Negative Breast Cancer (The TAILORx Trial) (PHASE3)
- Low Dose Tamoxifen With or Without Omega-3 Fatty Acids for Breast Cancer Risk Reduction (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 |
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