ABCSG 61 / TEODOR : Neoadjuvant TrEatment Optimization Driven by Circulating Tumor DNA and endOcrine Responsiveness
This is not medical advice. AI-assisted translation — inaccuracies may occur. Always verify the original and consult your oncologist before taking any steps.
About the trial
The goal of this performance study is to learn if treatment with neoadjuvant endocrine therapy compared to chemotherapy has comparable efficacy, but better quality of life outcomes in endocrine responsive participants with early and locally advanced ER+/HER2-negative breast cancer and no detectable ctDNA in peripheral blood. The main question it aims to answer is: Is neoadjuvant endocrine therapy at least equivalent to neoadjuvant chemotherapy for treatment of patients with ER-positive, HER2-negative breast cancer with no detectable ctDNA (as assessed with the SignateraTM test) prior to treatment start and a Ki-67-value smaller or equal to 10% after 3 weeks of initial aromatase inhibitor treatment (=endocrine responsive). Researchers will compare neoadjuvant Standard of Care aromatase inhibitors (AI) or tamoxifen, if AI is not tolerated, with neoadjuvant Standard of Care chemotherapy to see if treatment efficacy is at least comparable between the treatment arms, when measured with the modified preoperative endocrine prognostic index (PEPI) score at surgery. Participants will: * Provide blood and tumor samples for ctDNA-assessment with the SignateraTM test by Natera prior to treatment starts * Take AI therapy for 4 weeks in the initial Run-in phase * Undergo tumor biopsy after 3 weeks of AI for local evaluation of Ki-67 * Receive either 8 months of neoadjuvant Standard of Care AI/ tamoxifen or 6-8 months of neoadjuvant Standard of Care chemotherapy in one of the three treatment arms of the Main Treatment Phase, depending on SignateraTM test result and Ki-67 value after 3 weeks of AI therapy (see "detailed description" for details). * Visit the clinic for checkups and tests at timepoints: * Prior to starting trial treatment * 3 weeks after start of endocrine treatment in the Run-in phase * Approx. 1 week later, prior to start of Main Treatment * After half of the therapy in the Main Therapy Phase has been completed * Once Main Treatment Phase treatment is complete (after 7-9 months overall) * For surgery and post-surgery checkup * Annually during the 5 years follow-up phase after surgery. * A subset of patients, who receive adjuvant chemotherapy after surgery, are asked to come to site for an additional visit after completion of chemotherapy. * Provide blood samples for ctDNA-assessment and future research when visiting the clinic * Answer patient-reported questionnaires about their quality of life, symptoms and sexual health
Original English text from ClinicalTrials.gov
Who can (and can't) join
✓ Qualifies
- •Wiek co najmniej 18 lat
- •Potwierdzony histologicznie nowotwór piersi zaawansowany, jednostronny, receptory hormonalne dodatnie i HER2 ujemny
- •Stadium IIA-III według klasyfikacji AJCC
- •Wskazanie do chemioterapii uzgodnione przez zespół specjalistów
- •Brak poprzedniego leczenia raka piersi przed włączeniem do badania
- •Sprawność fizyczna 0-2 w skali ECOG
- •Prawidłowe wartości morfologii krwi i funkcji narządów wewnętrznych
- •Możliwość przełykania leków doustnych i zachłonięcia ich bez problemów
✗ Disqualifies
- •Brak możliwości poddania się operacji lub radioterapii piersi
- •Nowotwór obustronny lub jednoczesny w drugiej piersi
- •Stosowanie hormonalnej terapii zastępczej lub hormonalnych środków antykoncepcyjnych podczas badania
- •Przewlekłe leki uniemożliwiające chemioterapię
- •Uczestnictwo w innym badaniu klinicznym w ostatnich 30 dniach
Simplified criteria — AI translation
Trial details
- Minimum age
- 18 Years
- Maximum age
- 100 Years
- Last updated (source)
- October 28, 2025
- Sex
- No restrictions
Therapies / drugs in trial
Locations (14)
Allg. Gynäkologie u. gyn. Onkologie/Senologie
Vienna, Austria
Landesklinikum Baden BGZ; Abt. f. Allgemein- u. Viszeralchirurgie
Baden, Austria
Dornbirn BGZ; Frauenheilkunde u. Geburtshilfe
Dornbirn, Austria
Landeskrankenhaus Feldkirch Interne E
Feldkirch, Austria
MUG - LKH Graz Klin. Abt. f. Onkologie
Graz, Austria
MUG - Univ. Frauenklinik Graz, Gyn. Abteilung
Graz, Austria
MUI - Univ. Klinik f. Frauenheilkunde Innsbruck Klin. Abteilung f. Gynäkologie u. Geburtshilfe
Innsbruck, Austria
TumorZentrum Kepler Universitätsklinikum Linz
Linz, Austria
LKH Salzburg - PMU, Univ.Klinik f. Innere Medizin III / SCRI CCCIT
Salzburg, Austria
Universitätsklinikum St. Pölten, Klin. Abteilung f. Innere Medizin 1
Sankt Pölten, Austria
KH BHB St. Veit/Glan Brustzentrum Kärnten
Sankt Veit an der Glan, Austria
Hanusch Krankenhaus, 3. Medizinische Abteilung
Vienna, Austria
Klinik Hietzing, Gyn. Abteilung; Karl Landsteiner Institut f. gyn. Onkologie u. Senologie
Vienna, Austria
Universitätsklinikum Wiener Neustadt, Abteilung für Innere Medizin, Hämatologie und int. Onkologie
Wiener Neustadt, Austria
Trial contact
Katharina Jarolim, PhD
Contact information from ClinicalTrials.gov. Contact in English.
Share this trial
Data from ClinicalTrials.gov. AI-assisted translation, last sync: 7/1/2026.
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