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Estrogen Antagonists
Estrogen antagonists block the activity of estrogen receptors to inhibit estrogen-driven cell growth, particularly in hormone-sensitive cancers.
Estrogen antagonists block the activity of estrogen receptors to inhibit estrogen-driven cell growth, particularly in hormone-sensitive cancers. Used for Estrogen receptor-positive breast cancer, Hormone-sensitive breast cancer (adjuvant or metastatic).
At a glance
| Generic name | Estrogen Antagonists |
|---|---|
| Sponsor | Alliance for Clinical Trials in Oncology |
| Drug class | Estrogen receptor antagonist |
| Target | Estrogen receptor (ER-α, ER-β) |
| Modality | Small molecule |
| Therapeutic area | Oncology |
| Phase | Phase 3 |
Mechanism of action
Estrogen antagonists (also called estrogen receptor antagonists or anti-estrogens) bind to and block estrogen receptors on cancer cells, preventing estrogen from activating these receptors and promoting tumor cell proliferation. This mechanism is particularly effective in estrogen receptor-positive (ER+) breast cancers and other hormone-sensitive malignancies. By antagonizing estrogen signaling, these agents can induce cell cycle arrest and apoptosis in estrogen-dependent tumors.
Approved indications
- Estrogen receptor-positive breast cancer
- Hormone-sensitive breast cancer (adjuvant or metastatic)
Common side effects
- Hot flashes
- Vaginal bleeding or discharge
- Thromboembolic events
- Endometrial hyperplasia or cancer
- Nausea
- Fatigue
Key clinical trials
- Menopausal Hormones and Sympathetic Activation (PHASE4)
- Comparison of Oral Dydrogesterone and Vaginal Progesterone in Menopausal Hormone Therapy (NA)
- A Study of Imlunestrant (LY3484356) in Premenopausal Women With Estrogen Receptor-Positive (ER+) Human Epidermal Growth Factor Receptor 2 Negative (HER2-) Early Breast Cancer (PHASE2)
- ORION-1: Study of AVZO-023 as a Single Agent and in Combination With AVZO-021, and/or Endocrine Therapy in Advanced Solid Tumors (PHASE1, PHASE2)
- Study of Belzutifan (MK-6482) Plus Fulvestrant for ER+/HER2- Metastatic Breast Cancer (MK-6482-029/LITESPARK-029) (PHASE2)
- Hormone Replacement Therapy in Adolescents With Premature Ovarian Insufficiency (PHASE3)
- SHAPE-ENDO: Multimodal Pre-Surgical Optimization in Patients With Obesity and Early-Stage Endometrial Cancer
- Evolutionary Clinical Trial for Novel Biomarker-Driven Therapies (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:
- Estrogen Antagonists CI brief — competitive landscape report
- Estrogen Antagonists updates RSS · CI watch RSS
- Alliance for Clinical Trials in Oncology portfolio CI