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tamoxifen + exemestane
This combination uses tamoxifen (a selective estrogen receptor modulator) and exemestane (an aromatase inhibitor) to block estrogen signaling through complementary pathways in hormone receptor-positive breast cancer.
This combination uses tamoxifen (a selective estrogen receptor modulator) and exemestane (an aromatase inhibitor) to block estrogen signaling through complementary pathways in hormone receptor-positive breast cancer. Used for Hormone receptor-positive breast cancer (adjuvant or metastatic setting).
At a glance
| Generic name | tamoxifen + exemestane |
|---|---|
| Sponsor | Pfizer |
| Drug class | Hormonal therapy combination (selective estrogen receptor modulator + aromatase inhibitor) |
| Target | Estrogen receptor alpha (ESR1) and aromatase (CYP19A1) |
| Modality | Small molecule |
| Therapeutic area | Oncology |
| Phase | Phase 3 |
Mechanism of action
Tamoxifen competitively blocks estrogen binding to estrogen receptors in breast tissue, while exemestane irreversibly inhibits the aromatase enzyme that converts androgens to estrogen in postmenopausal women. Together, they provide dual suppression of estrogen-driven proliferation in hormone-sensitive breast cancer cells through receptor antagonism and reduced estrogen synthesis.
Approved indications
- Hormone receptor-positive breast cancer (adjuvant or metastatic setting)
Common side effects
- Hot flashes
- Vaginal dryness/atrophy
- Arthralgia/myalgia
- Fatigue
- Nausea
- Thromboembolic events
- Endometrial hyperplasia/cancer (tamoxifen)
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)
- Hormone Therapy With or Without Combination Chemotherapy in Treating Women Who Have Undergone Surgery for Node-Negative Breast Cancer (The TAILORx Trial) (PHASE3)
- Tamoxifen Citrate, Letrozole, Anastrozole, or Exemestane With or Without Chemotherapy in Treating Patients With Invasive RxPONDER Breast Cancer (PHASE3)
- Ribociclib And Endocrine Treatment of Physician's Choice for Locoregional Recurrent, Resected Hormone Receptor Positive HER2 Negative Breast Cancer (PHASE2)
- A Study of the Impact of Endocrine Therapy on Surgical Outcomes in People With Breast Cancer (PHASE2)
- Letrozole, Anastrozole, Exemestane, or Tamoxifen Citrate in Treating Postmenopausal Women With Breast Cancer (PHASE3)
- DCIS: RECAST Trial Ductal Carcinoma In Situ: Re-Evaluating Conditions for Active Surveillance Suitability as Treatment (PHASE2)
- Prototype DAA/TAA Vaccine Targeting MUC1 for Immune Interception and Prevention in Ductal Carcinoma In Situ (PHASE1)
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 + exemestane CI brief — competitive landscape report
- tamoxifen + exemestane updates RSS · CI watch RSS
- Pfizer portfolio CI