{"entity":{"id":"nct03941730","kind":"trial","name":"Estradiol in ER-beta-positive TNBC","aka":["Estradiol in Treating Patients With ER Beta Positive, Triple Negative Locally Advanced or Metastatic Breast Cancer"],"tldr":"This study tests estradiol in triple-negative breast cancers that express a different estrogen receptor, ER beta. That selection differs from the usual ER-alpha test used to classify breast cancer.","summary":"This study tests estradiol in triple-negative breast cancers that express a different estrogen receptor, ER beta. That selection differs from the usual ER-alpha test used to classify breast cancer.\n\nInterventional study registered as NCT03941730, sponsored by Mayo Clinic. Registry phase: 2. Registry enrollment is 8 participants (actual). Registry status checked October 10, 2026: active not recruiting. UCSF lists this study as closed to local enrollment; local availability and overall registry status are separate. See the registry for full eligibility and current sites.","status":"active","asOf":"2026-10-10","links":[{"label":"ClinicalTrials.gov NCT03941730","url":"https://clinicaltrials.gov/study/NCT03941730"},{"label":"UCSF study listing and local availability","url":"https://clinicaltrials.ucsf.edu/trial/NCT03941730"}],"tags":["ucsf-breast-coverage","interventional"],"related":[],"cancers":["breast-cancer","tnbc"],"sections":[],"technologies":[],"targets":[],"drugs":[],"companies":[],"institutions":["ucsf"],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"nct":"NCT03941730","phase":"2","setting":"ER-beta-positive locally advanced or metastatic triple-negative breast cancer","sponsor":"Mayo Clinic","participation":[{"nct":"NCT03941730","source":"https://clinicaltrials.gov/study/NCT03941730","fetchedAt":"2026-10-10T20:54:21.165516Z","studySha256":"10c37510e73fdd5227cd1badd9534216b15fd0514c0b7946ecfe24d26c3f1e9c","overallStatus":"ACTIVE_NOT_RECRUITING","lastUpdatePosted":"2026-05-12","leadSponsor":"Mayo Clinic","collaboratorCount":1,"minimumAge":"18 Years","sex":"FEMALE","healthyVolunteers":false,"hasEligibility":true,"enrolment":8,"enrolmentType":"ACTUAL","siteCount":9,"recruitingSiteCount":0,"countries":["United States"]}],"started":"2019-08-28","startedType":"actual","enrolled":8,"enrolledBasis":"registry","outcomes":[]},"route":"/trials/nct03941730/","neighbours":{"cancer":[{"id":"breast-cancer","kind":"cancer","name":"Breast cancer (all types)","route":"/cancers/breast-cancer/"},{"id":"tnbc","kind":"cancer","name":"Triple-negative breast cancer (TNBC)","route":"/cancers/tnbc/"}],"institution":[{"id":"ucsf","kind":"institution","name":"UCSF Helen Diller Family Comprehensive Cancer Center","route":"/institutions/ucsf/"}]}}