{"id":"estrogen-antagonists","safety":{"commonSideEffects":[{"rate":null,"effect":"Hot flashes"},{"rate":null,"effect":"Vaginal bleeding or discharge"},{"rate":null,"effect":"Thromboembolic events"},{"rate":null,"effect":"Endometrial hyperplasia or cancer"},{"rate":null,"effect":"Nausea"},{"rate":null,"effect":"Fatigue"}]},"_chembl":null,"_dailymed":null,"mechanism":{"_ai_source":"claude-haiku-4.5","explanation":"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.","oneSentence":"Estrogen antagonists block the activity of estrogen receptors to inhibit estrogen-driven cell growth, particularly in hormone-sensitive cancers.","_ai_confidence":"medium"},"_scrapedAt":"2026-03-28T01:11:40.105Z","_scrapedBy":"cloudflare-swarm","_wikipedia":null,"indications":{"approved":[{"name":"Estrogen receptor-positive breast cancer"},{"name":"Hormone-sensitive breast cancer (adjuvant or metastatic)"}]},"trialDetails":[{"nctId":"NCT07420218","phase":"PHASE4","title":"Menopausal Hormones and Sympathetic Activation","status":"NOT_YET_RECRUITING","sponsor":"University of Delaware","startDate":"2026-09-01","conditions":"Perimenopausal Women","enrollment":80},{"nctId":"NCT07496294","phase":"NA","title":"Comparison of Oral Dydrogesterone and Vaginal Progesterone in Menopausal Hormone Therapy","status":"NOT_YET_RECRUITING","sponsor":"Sehit Prof. Dr. Ilhan Varank Sancaktepe Training and Research Hospital","startDate":"2026-04","conditions":"Menopausal Women, Menopausal Symptom Relief, Hormone Therapy","enrollment":200},{"nctId":"NCT07287098","phase":"PHASE2","title":"A Study of Imlunestrant (LY3484356) in Premenopausal Women With Estrogen Receptor-Positive (ER+) Human Epidermal Growth Factor Receptor 2 Negative (HER2-) Early Breast Cancer","status":"NOT_YET_RECRUITING","sponsor":"Eli Lilly and Company","startDate":"2026-05","conditions":"Breast Neoplasms","enrollment":600},{"nctId":"NCT06998407","phase":"PHASE1, PHASE2","title":"ORION-1: Study of AVZO-023 as a Single Agent and in Combination With AVZO-021, and/or Endocrine Therapy in Advanced Solid Tumors","status":"RECRUITING","sponsor":"Avenzo Therapeutics, Inc.","startDate":"2025-08-20","conditions":"HR+/HER2- Breast Cancer, HR+, HER2-, Advanced Breast Cancer","enrollment":380},{"nctId":"NCT06428396","phase":"PHASE2","title":"Study of Belzutifan (MK-6482) Plus Fulvestrant for ER+/HER2- Metastatic Breast Cancer (MK-6482-029/LITESPARK-029)","status":"RECRUITING","sponsor":"Merck Sharp & Dohme LLC","startDate":"2024-11-27","conditions":"Metastatic Breast Cancer","enrollment":120},{"nctId":"NCT06851754","phase":"PHASE3","title":"Hormone Replacement Therapy in Adolescents With Premature Ovarian Insufficiency","status":"RECRUITING","sponsor":"Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)","startDate":"2025-07-17","conditions":"Premature Ovarian Insufficiency","enrollment":185},{"nctId":"NCT07462663","phase":"","title":"SHAPE-ENDO: Multimodal Pre-Surgical Optimization in Patients With Obesity and Early-Stage Endometrial Cancer","status":"NOT_YET_RECRUITING","sponsor":"Hospital Universitari de Bellvitge","startDate":"2026-05","conditions":"Endometrial Cancer, Endometrial Cancer Stage I, Atypical Endometrial Hyperplasia and Endometrial Carcinoma Stage I","enrollment":82},{"nctId":"NCT07340541","phase":"PHASE2","title":"Evolutionary Clinical Trial for Novel Biomarker-Driven Therapies","status":"NOT_YET_RECRUITING","sponsor":"UNC Lineberger Comprehensive Cancer Center","startDate":"2026-02","conditions":"Breast Cancer, Metastatic Breast Cancer, Triple Negative Breast Cancer","enrollment":700},{"nctId":"NCT04576455","phase":"PHASE2","title":"A Study Evaluating the Efficacy and Safety of Giredestrant Compared With Physician's Choice of Endocrine Monotherapy in Participants With Previously Treated Estrogen Receptor-Positive, HER2-Negative Locally Advanced or Metastatic Breast Cancer (acelERA Breast Cancer)","status":"ACTIVE_NOT_RECRUITING","sponsor":"Hoffmann-La Roche","startDate":"2020-11-27","conditions":"Estrogen Receptor-Positive, HER2-Negative, Locally Advanced or Metastatic Breast Cancer","enrollment":303},{"nctId":"NCT00099437","phase":"PHASE3","title":"Comparison of Fulvestrant (FASLODEX™) 250 mg and 500 mg in Postmenopausal Women With Oestrogen Receptor Positive Advanced Breast Cancer Progressing or Relapsing After Previous Endocrine Therapy.","status":"ACTIVE_NOT_RECRUITING","sponsor":"AstraZeneca","startDate":"2005-02-13","conditions":"Breast Cancer","enrollment":736},{"nctId":"NCT05654623","phase":"PHASE3","title":"A Study to Learn About a New Medicine Called Vepdegestrant (ARV-471, PF-07850327) in People Who Have Advanced Metastatic Breast Cancer","status":"ACTIVE_NOT_RECRUITING","sponsor":"Pfizer","startDate":"2023-03-03","conditions":"Advanced Breast Cancer","enrollment":624},{"nctId":"NCT07222267","phase":"PHASE1","title":"An Investigational Study of BG-75202 Alone and in Combination With Other Therapeutic Agents in Adults With Advanced Solid Tumors","status":"RECRUITING","sponsor":"BeOne Medicines","startDate":"2025-12-11","conditions":"Breast Cancer, Advanced Solid Tumor","enrollment":86},{"nctId":"NCT06993844","phase":"PHASE1, PHASE2","title":"Phase 1/2 Study of ETX-636 in Participants With Advanced Solid Tumors","status":"RECRUITING","sponsor":"Ensem Therapeutics","startDate":"2025-06-10","conditions":"Advanced Solid Tumors, Advanced Breast Cancer","enrollment":233},{"nctId":"NCT06075953","phase":"PHASE2","title":"DCIS: RECAST Trial Ductal Carcinoma In Situ: Re-Evaluating Conditions for Active Surveillance Suitability as Treatment","status":"RECRUITING","sponsor":"QuantumLeap Healthcare Collaborative","startDate":"2024-02-17","conditions":"Ductal Carcinoma in Situ","enrollment":400},{"nctId":"NCT07085767","phase":"PHASE3","title":"Palazestrant in Combination With Ribociclib for the First-line Treatment of ER+/HER2- Advanced Breast Cancer","status":"RECRUITING","sponsor":"Olema Pharmaceuticals, Inc.","startDate":"2025-11-03","conditions":"Breast Cancer, Locally Advanced Breast Cancer, Metastatic Breast Cancer","enrollment":1000},{"nctId":"NCT06382948","phase":"PHASE3","title":"Elacestrant + Everolimus in Patients ER+/HER2-, ESR1mut, Advanced Breast Cancer Progressing to ET and CDK4/6i.","status":"RECRUITING","sponsor":"MedSIR","startDate":"2024-12-05","conditions":"Advanced Breast Cancer, ER-positive Breast Cancer, HER2-negative Breast Cancer","enrollment":240},{"nctId":"NCT07466498","phase":"PHASE2","title":"Estrogen to Improve Quality of Life for Men With Newly Diagnosed or Recurrent Metastatic Hormone Sensitive Prostate Cancer, EQUIP Trial","status":"NOT_YET_RECRUITING","sponsor":"University of Washington","startDate":"2026-08-01","conditions":"Castration-Sensitive Prostate Adenocarcinoma, Metastatic Castration-Sensitive Prostate Adenocarcinoma, Stage IVB Prostate Cancer AJCC v8","enrollment":60},{"nctId":"NCT06218303","phase":"PHASE1","title":"Prototype DAA/TAA Vaccine Targeting MUC1 for Immune Interception and Prevention in Ductal Carcinoma In Situ","status":"RECRUITING","sponsor":"Finn, Olivera, PhD","startDate":"2024-02-07","conditions":"Ductal Carcinoma in Situ","enrollment":50},{"nctId":"NCT04572295","phase":"PHASE1","title":"A Study of E7090 as Monotherapy and in Combination With Other Anticancer Agents in Participants With Estrogen Receptor Positive (ER+) and Human Epidermal Growth Receptor 2 Negative (HER2-) Recurrent/Metastatic Breast Cancer","status":"ACTIVE_NOT_RECRUITING","sponsor":"Eisai Co., Ltd.","startDate":"2020-10-09","conditions":"Breast Neoplasms","enrollment":51},{"nctId":"NCT05457972","phase":"PHASE4","title":"Postpartum Vaginal Estrogen for Breastfeeding Patients","status":"RECRUITING","sponsor":"University Hospitals Cleveland Medical Center","startDate":"2025-02-22","conditions":"Breastfeeding, Postpartum Sexual Dysfunction, Vaginal Atrophy","enrollment":100},{"nctId":"NCT06065748","phase":"PHASE3","title":"A Study to Evaluate Efficacy and Safety of Giredestrant Compared With Fulvestrant (Plus a CDK4/6 Inhibitor), in Participants With ER-Positive, HER2-Negative Advanced Breast Cancer Resistant to Adjuvant Endocrine Therapy (pionERA Breast Cancer)","status":"RECRUITING","sponsor":"Hoffmann-La Roche","startDate":"2023-12-11","conditions":"Estrogen Receptor-Positive, HER2-Negative Advanced Breast Cancer","enrollment":1050},{"nctId":"NCT06975111","phase":"PHASE2, PHASE3","title":"Focusing on the Menopausal Transition to Improve Mid-Life Women's Health","status":"NOT_YET_RECRUITING","sponsor":"University of Colorado, Denver","startDate":"2026-03-01","conditions":"Menopause, Menopause Hot Flashes, Menopause Related Conditions","enrollment":200},{"nctId":"NCT05700006","phase":"","title":"Pilot Observational Study Examining the Effect of Endocrine Therapy on Aging","status":"COMPLETED","sponsor":"University of Michigan","startDate":"2022-07-25","conditions":"Breast Neoplasm Female, Arthralgia, Aging","enrollment":94},{"nctId":"NCT05154487","phase":"PHASE2","title":"A Study of Alpelisib and Fulvestrant to Treat Endometrial Cancer","status":"ACTIVE_NOT_RECRUITING","sponsor":"GOG Foundation","startDate":"2024-09-11","conditions":"Endometroid Endometrial Cancer","enrollment":51},{"nctId":"NCT05879926","phase":"PHASE3","title":"Evaluating the Addition of Adjuvant Chemotherapy to Ovarian Function Suppression Plus Endocrine Therapy in Premenopausal Patients With pN0-1, ER-Positive/HER2-Negative Breast Cancer and an Oncotype Recurrence Score Less Than or Equal to 25","status":"RECRUITING","sponsor":"NRG Oncology","startDate":"2023-08-31","conditions":"Breast Cancer","enrollment":3960},{"nctId":"NCT05768139","phase":"PHASE1, PHASE2","title":"First-in-Human Study of STX-478 as Monotherapy and in Combination With Other Antineoplastic Agents in Participants With Advanced Solid Tumors","status":"RECRUITING","sponsor":"Eli Lilly and Company","startDate":"2023-04-17","conditions":"Breast Cancer, Solid Tumors, Adult","enrollment":720},{"nctId":"NCT07254429","phase":"PHASE2","title":"COMPASS - COpenhagen MenoPAuSe Study","status":"RECRUITING","sponsor":"Martin Blomberg Jensen","startDate":"2025-10-02","conditions":"Menopausal Osteoporosis, Bone Markers","enrollment":192},{"nctId":"NCT02767661","phase":"PHASE3","title":"Metronomic Capecitabine Plus Aromatase Inhibitor for First Line Treatment in HR(+), Her2(-) Metastatic Breast Cancer","status":"COMPLETED","sponsor":"Sun Yat-sen University","startDate":"2017-07-19","conditions":"Breast Cancer","enrollment":263},{"nctId":"NCT01597388","phase":"PHASE1","title":"AZD2014 and Fulvestrant in Patients With ER+ Advanced Metastatic Breast Cancer","status":"COMPLETED","sponsor":"AstraZeneca","startDate":"2012-05-08","conditions":"Advanced Metastatic Breast Cancer","enrollment":99},{"nctId":"NCT02778685","phase":"PHASE2","title":"Pembrolizumab, Endocrine Therapy, and Palbociclib in Treating Postmenopausal Patients With Newly Diagnosed Metastatic Stage IV Estrogen Receptor Positive Breast Cancer","status":"ACTIVE_NOT_RECRUITING","sponsor":"City of Hope Medical Center","startDate":"2016-09-30","conditions":"Metastatic Breast Carcinoma, Stage IV Breast Cancer AJCC v6 and v7","enrollment":47},{"nctId":"NCT04059484","phase":"PHASE2","title":"Phase 2 Study of Amcenestrant (SAR439859) Versus Physician's Choice in Locally Advanced or Metastatic ER-positive Breast Cancer","status":"TERMINATED","sponsor":"Sanofi","startDate":"2019-10-22","conditions":"Breast Cancer Metastatic","enrollment":367},{"nctId":"NCT07408089","phase":"PHASE1","title":"Study of the Kinesin Oral Molecular Degrader BBI-940 in Subjects With Advanced or Metastatic Breast Cancer","status":"RECRUITING","sponsor":"Boundless Bio, Inc.","startDate":"2026-02-25","conditions":"Breast Cancer, Metastatic Breast Cancer, Advanced Breast Cancer","enrollment":96},{"nctId":"NCT07425990","phase":"NA","title":"FET-LET-2x2: Clinical Pregnancy Rates After Frozen Embryo Transfer in Natural and Modified Natural Cycles","status":"NOT_YET_RECRUITING","sponsor":"University of Novi Sad","startDate":"2026-02","conditions":"Infertility Female, Frozen Embryo Transfer (FET)","enrollment":120},{"nctId":"NCT04961996","phase":"PHASE3","title":"A Study Evaluating the Efficacy and Safety of Adjuvant Giredestrant Compared With Physician's Choice of Adjuvant Endocrine Monotherapy in Participants With Estrogen Receptor-Positive, HER2-Negative Early Breast Cancer (lidERA Breast Cancer)","status":"ACTIVE_NOT_RECRUITING","sponsor":"Hoffmann-La Roche","startDate":"2021-08-27","conditions":"Early Breast Cancer","enrollment":4170},{"nctId":"NCT04546009","phase":"PHASE3","title":"A Study Evaluating the Efficacy and Safety of Giredestrant Combined With Palbociclib Compared With Letrozole Combined With Palbociclib in Participants With Estrogen Receptor-Positive, HER2-Negative Locally Advanced or Metastatic Breast Cancer (persevERA Breast Cancer)","status":"ACTIVE_NOT_RECRUITING","sponsor":"Hoffmann-La Roche","startDate":"2020-10-09","conditions":"Estrogen Receptor-Positive, HER2-Negative Locally Advanced or Metastatic Breast Cancer","enrollment":992},{"nctId":"NCT07422506","phase":"NA","title":"A Real-World Study Comparing the Efficacy of Different Treatment Regimens for Early Missed Abortion","status":"RECRUITING","sponsor":"The Third Xiangya Hospital of Central South University","startDate":"2024-01-01","conditions":"Missed Abortion, Early Pregnancy Failure","enrollment":580},{"nctId":"NCT07423611","phase":"PHASE2","title":"ctDNA-Guided Chemotherapy Omission With Ribociclib Plus Endocrine Therapy in HR-Positive/HER2-Negative Breast Cancer","status":"NOT_YET_RECRUITING","sponsor":"Fudan University","startDate":"2026-10-01","conditions":"Breast Cancer","enrollment":388},{"nctId":"NCT05672901","phase":"NA","title":"Silicone Gel vs. Estrogen Vaginal Cream for the Management of Genitourinary Syndrome of Menopause","status":"RECRUITING","sponsor":"Stratpharma AG","startDate":"2023-04-04","conditions":"Genitourinary Syndrome of Menopause","enrollment":100},{"nctId":"NCT07419594","phase":"NA","title":"Estradiol and Intrusive Memories","status":"RECRUITING","sponsor":"Charite University, Berlin, Germany","startDate":"2024-08-19","conditions":"PTSD, Intrusive Memories, Intrusion Symptom","enrollment":273},{"nctId":"NCT06440967","phase":"PHASE3","title":"A Study to Confirm if Fezolinetant Helps Reduce Hot Flashes in Women With Breast Cancer Who Are Having Hormone Therapy","status":"RECRUITING","sponsor":"Astellas Pharma Global Development, Inc.","startDate":"2024-07-31","conditions":"Hot Flashes","enrollment":540},{"nctId":"NCT05317364","phase":"PHASE4","title":"Topical Vaginal Estrogen for Postpartum Obstetric Anal Sphincter Injury Recovery","status":"TERMINATED","sponsor":"University of Alabama at Birmingham","startDate":"2022-07-14","conditions":"Obstetric; Injury Pelvic Floor, Sexual Dysfunction, Anal Incontinence","enrollment":38},{"nctId":"NCT03624244","phase":"PHASE2","title":"Evaluation of Clinical Impact of Interruption VS Maintenance of AI in Patients With Locally Advanced/ Metastatic Low Grade Endometrial Stromal Sarcoma (LGESS)","status":"RECRUITING","sponsor":"Centre Leon Berard","startDate":"2019-01-23","conditions":"Low Grade Endometrial Stromal Sarcoma","enrollment":40},{"nctId":"NCT06105632","phase":"PHASE2","title":"A Study to Learn About the Study Medicine Called PF-07220060 in Combination With Fulvestrant in People With HR-positive, HER2-negative Advanced or Metastatic Breast Cancer Who Progressed After a Prior Line of Treatment","status":"ACTIVE_NOT_RECRUITING","sponsor":"Pfizer","startDate":"2024-01-09","conditions":"Advanced or Metastatic Breast Cancer","enrollment":333},{"nctId":"NCT03332797","phase":"PHASE1","title":"A Study of GDC-9545 Alone or in Combination With Palbociclib and/or Luteinizing Hormone-Releasing Hormone (LHRH) Agonist in Locally Advanced or Metastatic Estrogen Receptor-Positive Breast Cancer","status":"ACTIVE_NOT_RECRUITING","sponsor":"Genentech, Inc.","startDate":"2017-11-24","conditions":"Breast Cancer","enrollment":181},{"nctId":"NCT05101564","phase":"PHASE2","title":"Umbrella Trial of Subtype-Targeted Therapies in ER+/HER2- Breast Cancer","status":"COMPLETED","sponsor":"Jennifer Lee Caswell-Jin","startDate":"2023-03-20","conditions":"Breast Cancer, HER2-negative Breast Cancer, ER Positive Breast Cancer","enrollment":19},{"nctId":"NCT07212712","phase":"NA","title":"The Role of Estrogen and Testosterone in Determining Brain Blood Flow and Metabolic Regulation in Humans","status":"NOT_YET_RECRUITING","sponsor":"University of British Columbia","startDate":"2026-04-01","conditions":"Cerebral Blood Flow, Cerebral Blood Flow Regulation, Sex Differences","enrollment":50},{"nctId":"NCT01674140","phase":"PHASE3","title":"S1207 Hormone Therapy With or Without Everolimus in Treating Patients With Breast Cancer","status":"ACTIVE_NOT_RECRUITING","sponsor":"SWOG Cancer Research Network","startDate":"2013-09-12","conditions":"Breast Cancer","enrollment":1939},{"nctId":"NCT07400523","phase":"PHASE3","title":"Ribociclib in Hormone Receptor-positive, HER2-negative Early Breast Cancer With Residual Disease After Neoadjuvant Chemotherapy","status":"NOT_YET_RECRUITING","sponsor":"Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University","startDate":"2026-02-10","conditions":"Breast Cancer","enrollment":446},{"nctId":"NCT06780163","phase":"PHASE4","title":"Effect of Vaginal Estrogen on Alterations in the Urine Microbiome of Menopausal Women With Overactive Bladder","status":"COMPLETED","sponsor":"Mahidol University","startDate":"2025-06-27","conditions":"Overactive Bladder (OAB), Menopause, Microbiome","enrollment":30},{"nctId":"NCT00066703","phase":"PHASE3","title":"Triptorelin With Either Exemestane or Tamoxifen in Treating Premenopausal Women With Hormone-Responsive Breast Cancer","status":"COMPLETED","sponsor":"ETOP IBCSG Partners Foundation","startDate":"2003-11-03","conditions":"Breast Cancer","enrollment":2672},{"nctId":"NCT04499131","phase":"PHASE4","title":"Impact of Different Doses and Routes of Exogenous Progesterone Administration on Endometrial Receptivity Parameters","status":"COMPLETED","sponsor":"Instituto Valenciano de Infertilidad, IVI VALENCIA","startDate":"2021-12-09","conditions":"Infertility, Female, ENDOMETRIAL RECEPTIVITY","enrollment":109},{"nctId":"NCT04255160","phase":"PHASE4","title":"Impact of Estradiol on Endothelial Function in Peri-Menopausal Women","status":"ACTIVE_NOT_RECRUITING","sponsor":"University of Delaware","startDate":"2020-10-01","conditions":"Perimenopause, Vasodilation, Estrogen","enrollment":80},{"nctId":"NCT07379502","phase":"NA","title":"Endometrial Response in Polycystic Ovarian Syndrome Treated With Letrozole Alone or With Added Estradiol Valerate","status":"NOT_YET_RECRUITING","sponsor":"CMH Kharian Medical College","startDate":"2026-03-05","conditions":"PCOS (Polycystic Ovary Syndrome)","enrollment":60},{"nctId":"NCT05306340","phase":"PHASE3","title":"A Study Evaluating the Efficacy and Safety of Giredestrant Plus Everolimus Compared With the Physician's Choice of Endocrine Therapy Plus Everolimus in Participants With Estrogen Receptor-Positive, HER2-Negative, Locally Advanced or Metastatic Breast Cancer (evERA Breast Cancer)","status":"ACTIVE_NOT_RECRUITING","sponsor":"Genentech, Inc.","startDate":"2022-08-03","conditions":"Estrogen Receptor (ER)-Positive, HER2-negative, Locally Advanced or Metastatic Breast Cancer","enrollment":373},{"nctId":"NCT06534125","phase":"NA","title":"Acutherapy to Prevent Aromatase Inhibitor-Associated Arthralgias in Non-Hispanic Black Postmenopausal Women With Early-Stage Breast Cancer","status":"RECRUITING","sponsor":"Emory University","startDate":"2024-12-12","conditions":"Anatomic Stage I Breast Cancer AJCC v8, Anatomic Stage II Breast Cancer AJCC v8, Anatomic Stage III Breast Cancer AJCC v8","enrollment":150},{"nctId":"NCT04650581","phase":"PHASE3","title":"Fulvestrant and Ipatasertib for Advanced HER-2 Negative and Estrogen Receptor Positive (ER+) Breast Cancer Following Progression on First Line CDK 4/6 Inhibitor and Aromatase Inhibitor","status":"ACTIVE_NOT_RECRUITING","sponsor":"Canadian Cancer Trials Group","startDate":"2021-01-27","conditions":"Breast Cancer","enrollment":250},{"nctId":"NCT01984138","phase":"PHASE2","title":"REVIVE: Replens Versus Intra-Vaginal Estrogen for the Treatment of Vaginal Dryness on Aromatase Inhibitor Therapy","status":"ACTIVE_NOT_RECRUITING","sponsor":"Polly A. Niravath, MD","startDate":"2013-09","conditions":"Estrogen Receptor Positive Breast Cancer, Breast Cancer","enrollment":33},{"nctId":"NCT03781063","phase":"PHASE2","title":"Evaluation of Lasofoxifene Versus Fulvestrant in Advanced or Metastatic ER+/HER2- Breast Cancer With an ESR1 Mutation","status":"COMPLETED","sponsor":"Sermonix Pharmaceuticals Inc.","startDate":"2019-09-20","conditions":"Locally Advanced or Metastatic Breast Cancer","enrollment":100},{"nctId":"NCT06913075","phase":"NA","title":"FET in Adenomyosis","status":"NOT_YET_RECRUITING","sponsor":"Indira IVF Hospital Pvt Ltd","startDate":"2026-06-25","conditions":"Adenomyosis","enrollment":700},{"nctId":"NCT07366632","phase":"PHASE1","title":"A Study of Single Dose of BL0175 in Postmenopausal Women","status":"NOT_YET_RECRUITING","sponsor":"Shanghai Best-Link Bioscience, LLC","startDate":"2026-01-26","conditions":"Postmenopausal Women","enrollment":27},{"nctId":"NCT07361263","phase":"NA","title":"Plasma Oxytocin Response to Oral Estrogens in Healthy Controls and AVP-Deficiency","status":"RECRUITING","sponsor":"University Hospital, Basel, Switzerland","startDate":"2026-01-09","conditions":"AVP Deficiency, Diabetes Insipidus","enrollment":28},{"nctId":"NCT01953588","phase":"PHASE3","title":"Fulvestrant and/or Anastrozole in Treating Postmenopausal Patients With Stage II-III Breast Cancer Undergoing Surgery","status":"ACTIVE_NOT_RECRUITING","sponsor":"Alliance for Clinical Trials in Oncology","startDate":"2014-02-27","conditions":"Estrogen Receptor-positive Breast Cancer, HER2-negative Breast Cancer, Invasive Ductal Breast Carcinoma","enrollment":1473},{"nctId":"NCT06353269","phase":"PHASE4","title":"Adherence to Vaginal Estrogen Therapy in Hypoestrogenic Women With Recurrent Urinary Tract Infections","status":"ACTIVE_NOT_RECRUITING","sponsor":"University of California, Irvine","startDate":"2024-06-14","conditions":"Recurrent Urinary Tract Infection, Hypoestrogenism","enrollment":111},{"nctId":"NCT06873971","phase":"NA","title":"Er:YAG Laser Combined With Vaginal Estriol for Genitourinary Syndrome of Menopause","status":"RECRUITING","sponsor":"University of Nove de Julho","startDate":"2025-12-10","conditions":"Genitourinary Syndrome of Menopause","enrollment":60},{"nctId":"NCT06970912","phase":"PHASE2","title":"ctDNA-Guided De-Escalation of Adjuvant Chemotherapy With Dalpiciclib in HR-Positive/HER2-Negative Breast Cancer","status":"RECRUITING","sponsor":"Peking University People's Hospital","startDate":"2025-08-01","conditions":"Hormone Receptor-Positive Breast Cancer, High-risk Breast Cancer, Early-Stage Breast Cancer","enrollment":393},{"nctId":"NCT04356664","phase":"PHASE2, PHASE3","title":"Benefit of GnRH Agonist Before Frozen Embryo Transfer in Patients With Endometriosis and/or Adenomyosis","status":"RECRUITING","sponsor":"Hopital Foch","startDate":"2021-03-18","conditions":"Endometriosis, Adenomyosis, Infertility, Female","enrollment":180},{"nctId":"NCT04964934","phase":"PHASE3","title":"Phase III Study to Assess AZD9833+ CDK4/6 Inhibitor in HR+/HER2-MBC With Detectable ESR1m Before Progression (SERENA-6)","status":"ACTIVE_NOT_RECRUITING","sponsor":"AstraZeneca","startDate":"2021-06-30","conditions":"ER-Positive HER2-Negative Breast Cancer","enrollment":315},{"nctId":"NCT05296798","phase":"PHASE3","title":"A Study to Evaluate the Efficacy and Safety of Giredestrant in Combination With Phesgo (Pertuzumab, Trastuzumab, and Hyaluronidase-zzxf) Versus Phesgo in Participants With Locally Advanced or Metastatic Breast Cancer (heredERA Breast Cancer)","status":"ACTIVE_NOT_RECRUITING","sponsor":"Hoffmann-La Roche","startDate":"2022-07-18","conditions":"Locally Advanced or Metastatic Breast Cancer","enrollment":922},{"nctId":"NCT06001762","phase":"PHASE2","title":"TRADE: Dose Escalation Tolerability of Abemaciclib in HR+ HER2- Early Stage Breast Cancer","status":"ACTIVE_NOT_RECRUITING","sponsor":"Dana-Farber Cancer Institute","startDate":"2023-10-05","conditions":"Breast Cancer, Early-stage Breast Cancer, High Risk Breast Carcinoma","enrollment":90},{"nctId":"NCT05716516","phase":"PHASE2","title":"STUDY02001740;22SCH740: Estradiol For ER+ Advanced Breast Cancer (ESTHER)","status":"RECRUITING","sponsor":"Dartmouth-Hitchcock Medical Center","startDate":"2023-05-04","conditions":"Metastatic Breast Cancer","enrollment":36},{"nctId":"NCT05826964","phase":"PHASE2","title":"Levels of Circulating Tumor DNA as a Predictive Marker for Early Switch in Treatment for Patients With Metastatic (Stage IV) Breast Cancer","status":"ACTIVE_NOT_RECRUITING","sponsor":"University of Miami","startDate":"2023-06-12","conditions":"Breast Cancer, ER-positive Breast Cancer, HER2-negative Breast Cancer","enrollment":24},{"nctId":"NCT04192266","phase":"PHASE3","title":"Estrogen and Fear in PTSD","status":"COMPLETED","sponsor":"The University of Texas Health Science Center, Houston","startDate":"2020-06-24","conditions":"PTSD","enrollment":83},{"nctId":"NCT05365178","phase":"PHASE3","title":"To Evaluate the Efficacy and Safety of TQB3616 in Combination With Fulvestrant Versus Placebo in Combination With Fulvestrant in Previously Untreated Hormone-receptor (HR)-Positive, Human Epidermal Growth Factor Receptor 2 (HER2)-Negative Advanced Breast Cancer","status":"ACTIVE_NOT_RECRUITING","sponsor":"Chia Tai Tianqing Pharmaceutical Group Co., Ltd.","startDate":"2022-07-01","conditions":"HR-positive, HER2-negative Breast Neoplasms","enrollment":432},{"nctId":"NCT07318805","phase":"PHASE1","title":"A Study to Learn About the Study Medicine Called PF-08032562 in People With Advanced or Metastatic Solid Tumors","status":"RECRUITING","sponsor":"Pfizer","startDate":"2025-12-16","conditions":"Advanced Breast Cancer, Metastatic Breast Cancer (HR+/ HER2-), Colorectal Cancer","enrollment":260},{"nctId":"NCT04762979","phase":"PHASE2","title":"Alpelisib (BYL719) in Combination With Continued Endocrine Therapy Following Progression on Endocrine Therapy in Hormone Receptor Positive, HER2 Negative, PIK3CA Mutant Metastatic Breast Cancer","status":"ACTIVE_NOT_RECRUITING","sponsor":"Marina N Sharifi","startDate":"2021-02-12","conditions":"Hormone Receptor Positive Breast Carcinoma, HER2-negative Breast Cancer, PIK3CA Mutant Metastatic Breast Cancer","enrollment":44},{"nctId":"NCT02760030","phase":"PHASE2","title":"Endocrine Therapy Fulvestrant & Palbociclib or Aromatase Inhibitor Therapy in Treating Older Patients With Hormone Responsive Breast Cancer That Cannot Be Removed by Surgery","status":"COMPLETED","sponsor":"Ohio State University Comprehensive Cancer Center","startDate":"2017-02-16","conditions":"Estrogen Receptor and/or Progesterone Receptor Positive, HER2/Neu Negative, Stage IA Breast Cancer","enrollment":14},{"nctId":"NCT07062965","phase":"PHASE3","title":"A Study to Learn About the Study Medicine Called PF-07248144 in Combination With Fulvestrant in People With HR-positive, HER2-negative Advanced or Metastatic Breast Cancer Who Progressed After a Prior Line of Treatment.","status":"RECRUITING","sponsor":"Pfizer","startDate":"2025-08-05","conditions":"Breast Cancer","enrollment":400},{"nctId":"NCT07278323","phase":"PHASE4","title":"Frozen Shoulder and Hormone Replacement Therapy","status":"NOT_YET_RECRUITING","sponsor":"University of California, San Francisco","startDate":"2026-01-01","conditions":"Adhesive Capsulitis of the Shoulder, Frozen Shoulder","enrollment":60},{"nctId":"NCT06851442","phase":"PHASE1, PHASE2","title":"Clinical Trial of Evaluating TQB3912 Tablets Combined With Fulvestrant Injection±TQB3616 Capsules for Locally Advanced or Metastatic Hormone Receptor(HR)-Positive and Human Epidermal Growth Factor Receptor 2 (HER2)-Negative Breast Cancer","status":"TERMINATED","sponsor":"Chia Tai Tianqing Pharmaceutical Group Co., Ltd.","startDate":"2025-05-16","conditions":"Breast Cancer","enrollment":8},{"nctId":"NCT06107673","phase":"PHASE2","title":"Dalpiciclib Plus AI (Neoadjuvant Endocrine Therapy) Compared With Neoadjuvant Chemotherapy in Early Breast Cancer （EBC）","status":"RECRUITING","sponsor":"Hebei Medical University Fourth Hospital","startDate":"2023-09-30","conditions":"Breast Cancer","enrollment":144},{"nctId":"NCT01723774","phase":"PHASE2","title":"PD 0332991 and Anastrozole for Stage 2 or 3 Estrogen Receptor Positive and HER2 Negative Breast Cancer","status":"ACTIVE_NOT_RECRUITING","sponsor":"Washington University School of Medicine","startDate":"2013-04-10","conditions":"Breast Neoplasms","enrollment":84},{"nctId":"NCT00984399","phase":"NA","title":"Serum Estradiol Levels In Postmenopausal Women With Breast Cancer Receiving Adjuvant Aromatase Inhibitors and Vaginal Estrogen","status":"COMPLETED","sponsor":"Memorial Sloan Kettering Cancer Center","startDate":"2009-09-22","conditions":"Atrophic Vaginitis, Breast Cancer","enrollment":31},{"nctId":"NCT07260825","phase":"PHASE2, PHASE3","title":"Use of Topical Testosterone and Estrogen vs Estrogen Alone in Vulvodynia: a Randomized Controlled Trial","status":"NOT_YET_RECRUITING","sponsor":"TriHealth Inc.","startDate":"2025-12","conditions":"Vulvodynia, Dyspareunia, Lichen Sclerosus of Vulva","enrollment":44},{"nctId":"NCT06706414","phase":"PHASE1, PHASE2","title":"NT-NOA - Novel Treatment of Some Men With Non-Obstructive Azoospermia","status":"ACTIVE_NOT_RECRUITING","sponsor":"Martin Blomberg Jensen","startDate":"2025-03-01","conditions":"Infertility, Male","enrollment":16},{"nctId":"NCT06520982","phase":"EARLY_PHASE1","title":"Early Neurovascular Adaptations in Aging Women","status":"RECRUITING","sponsor":"University of Missouri-Columbia","startDate":"2024-09-20","conditions":"Women, Sympathetic Nervous System, Aging","enrollment":64},{"nctId":"NCT05388656","phase":"PHASE4","title":"Estrogen Variability and Irritability During the Menopause Transition","status":"COMPLETED","sponsor":"University of North Carolina, Chapel Hill","startDate":"2022-06-15","conditions":"Menopause, Irritable Mood","enrollment":40},{"nctId":"NCT02630693","phase":"PHASE2","title":"Two Different Schedules of Palbociclib + Second Line Endocrine Therapy in Estrogen Receptor Positive, HER2 Neg Advanced/Metastatic Breast Cancer","status":"COMPLETED","sponsor":"Canadian Cancer Trials Group","startDate":"2016-04-08","conditions":"Breast Cancer","enrollment":180},{"nctId":"NCT06495164","phase":"","title":"A Real-life Study to Understand the Use and Effects of Palbociclib in US Patients With Breast Cancer","status":"ACTIVE_NOT_RECRUITING","sponsor":"Pfizer","startDate":"2024-06-24","conditions":"Breast Cancer, Malignant Neoplasm of Breast","enrollment":1},{"nctId":"NCT05266105","phase":"PHASE1","title":"A Phase 1 Study of Oral OP-1250 in Combination With Palbociclib in HR+/HER2- Breast Cancer Patients","status":"ACTIVE_NOT_RECRUITING","sponsor":"Olema Pharmaceuticals, Inc.","startDate":"2021-12-10","conditions":"Breast Cancer","enrollment":60},{"nctId":"NCT05867251","phase":"PHASE1, PHASE2","title":"Study of AVZO-021 in Patients With Advanced Solid Tumors","status":"RECRUITING","sponsor":"Avenzo Therapeutics, Inc.","startDate":"2023-08-30","conditions":"Advanced Solid Tumor, HR+/HER2- Breast Cancer, HR+, HER2-, Advanced Breast Cancer","enrollment":430},{"nctId":"NCT06086340","phase":"","title":"Study to Compare Overall Survival in Medicare Patients With Metastatic Breast Cancer Treated With a Medicine Called Palbociclib in Combination With Aromatase Inhibitor and Aromatase Inhibitor by Itself.","status":"COMPLETED","sponsor":"Pfizer","startDate":"2023-09-29","conditions":"Breast Cancer","enrollment":779},{"nctId":"NCT03079011","phase":"PHASE3","title":"PAlbociclib and Circulating Tumor DNA for ESR1 Mutation Detection","status":"COMPLETED","sponsor":"UNICANCER","startDate":"2017-03-22","conditions":"Metastatic Breast Cancer","enrollment":1017},{"nctId":"NCT06369363","phase":"EARLY_PHASE1","title":"Estrogen Deficiency on Cardiovascular Risk","status":"NOT_YET_RECRUITING","sponsor":"Milton S. Hershey Medical Center","startDate":"2026-09","conditions":"Postmenopausal Symptoms, Cardiovascular Diseases","enrollment":20},{"nctId":"NCT05704036","phase":"PHASE4","title":"Estrogen Supplementation and Bone Health in Women With CF","status":"RECRUITING","sponsor":"Johns Hopkins University","startDate":"2023-05-02","conditions":"Cystic Fibrosis, Hypoestrogenism","enrollment":75},{"nctId":"NCT05645406","phase":"EARLY_PHASE1","title":"Estrogen Hormone Products","status":"COMPLETED","sponsor":"University of Maryland, Baltimore","startDate":"2024-05-14","conditions":"Menopause","enrollment":8},{"nctId":"NCT05607004","phase":"PHASE2","title":"(Z)-Endoxifen for the Treatment of Premenopausal Women With ER+/HER2- Breast Cancer","status":"RECRUITING","sponsor":"Atossa Therapeutics, Inc.","startDate":"2023-02-14","conditions":"Breast Neoplasms, Invasive Breast Cancer, Estrogen-receptor-positive Breast Cancer","enrollment":87},{"nctId":"NCT03620643","phase":"PHASE2","title":"Crizotinib in Lobular Breast, Diffuse Gastric and Triple Negative Lobular Breast Cancer or CDH1-mutated Solid Tumours","status":"COMPLETED","sponsor":"Royal Marsden NHS Foundation Trust","startDate":"2019-05-09","conditions":"Lobular Breast Carcinoma, Gastric Cancer, Triple Negative Breast Cancer","enrollment":33},{"nctId":"NCT04821375","phase":"EARLY_PHASE1","title":"Pilot Study of Bazedoxifene Plus Conjugated Estrogen on Imaging and Blood Biomarkers","status":"COMPLETED","sponsor":"Carol Fabian, MD","startDate":"2021-12-02","conditions":"Increased Risk for Development of Breast Cancer","enrollment":16},{"nctId":"NCT04821141","phase":"PHASE2","title":"Phase IIB Trial of Bazedoxifene Plus Conjugated Estrogens","status":"ACTIVE_NOT_RECRUITING","sponsor":"University of Kansas Medical Center","startDate":"2021-12-14","conditions":"Risk Reduction, Breast Cancer","enrollment":120},{"nctId":"NCT06610305","phase":"PHASE4","title":"Ovarian Hormone Withdrawal, Anhedonia, and Reward Sensitivity in Women With Premenstrual Exacerbations of Depression","status":"RECRUITING","sponsor":"University of North Carolina, Chapel Hill","startDate":"2024-09-02","conditions":"Major Depressive Disorder","enrollment":75}],"_emaApprovals":[],"_faersSignals":[],"_approvalHistory":[],"publicationCount":203,"rwe":[],"genericFilers":[],"relatedDrugs":[],"labelChanges":[],"biosimilarFilings":[],"pricing":[],"formularyStatus":[],"manufacturing":[],"companionDiagnostics":[],"competitors":[],"timeline":[],"patents":[],"ownershipHistory":[],"trials":[],"biosimilars":[],"latestUpdates":[],"references":[],"tags":[],"ecosystem":[],"genericManufacturerList":[],"offLabel":[],"developmentCodes":[],"aliases":[],"phase":"phase_3","status":"active","brandName":"Estrogen Antagonists","genericName":"Estrogen Antagonists","companyName":"Alliance for Clinical Trials in Oncology","companyId":"alliance-for-clinical-trials-in-oncology","modality":"Small molecule","firstApprovalDate":"","aiSummary":"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).","enrichmentLevel":3,"visitCount":0,"trialStats":{"total":0,"withResults":0},"verificationStatus":"verified","dataCompleteness":{"mechanism":true,"indications":true,"safety":true,"trials":true,"score":4}}