Why some new treatments work or stop working in advanced breast cancer
Official title: Mechanisms of Response and Resistance to Innovative Treatments in Patients With Locally Advanced or Metastatic Breast Cancer
Run by Hellenic Cooperative Oncology Group · NCT07066917 · Data updated 2026-11-12
This project will see if biological markers explain why people with advanced breast cancer respond or become resistant to newer treatments like ADCs, immunotherapy, CDK inhibitors, and PARP inhibitors.
Quick facts
| Study type | Observational |
|---|---|
| Ages | 18 Years and up |
| Sex | Women only |
| Enrollment | 150 (estimated) |
| Sponsor | Hellenic Cooperative Oncology Group Academic / other |
| Locations | 5 sites (Athens and 4 other locations) |
| Status | Recruiting |
| Started | October 15, 2024 |
| Main results expected | October 2029 |
| Study ends | October 2029 |
| Registry record updated | October 14, 2026 |
| Trial ID | NCT07066917 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Adults (≥18) with histologically confirmed locally advanced or metastatic breast cancer of any subtype who have received at least one treatment cycle and are willing to provide consent and biological specimens are ideal candidates.
✕Probably not a fit
Patients with early (non‑advanced) breast cancer, those unwilling to provide informed consent or biospecimens, or those lacking comprehensive clinical data will not be eligible and are unlikely to benefit from this project.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
This is an observational program enrolling adults with locally advanced or metastatic breast cancer across hormone receptor–positive, HER2‑positive/-low, and triple‑negative subtypes. Participants who have received at least one treatment cycle will contribute clinical data and biological specimens for molecular and biomarker analyses. Researchers will correlate treatment type, clinical outcomes, and adverse events with molecular features to identify mechanisms of response and resistance. No experimental treatments are given as part of the protocol; care follows standard clinical practice at participating centers in Athens, Greece.
Why it matters
Potential benefit: If successful, the work could help doctors choose and sequence treatments more effectively so patients receive therapies most likely to help them.
How similar studies have gone: Prior research has identified predictors for specific agents (for example, BRCA mutations for PARP inhibitors and PD‑L1 for some immune therapies), but comprehensive, integrated analyses across multiple new drug classes remain limited.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: * Eligible patients will be 18 years of age and older * Histologically confirmed, advanced breast cancer. * Diagnosis of i) hormone receptor positive and/or ii) HER2-positive or -low or iii) triple negative breast cancer (TNBC). * Patients will be included in the analysis after receiving at least one treatment cycle. Exclusion Criteria: * Diagnosis of early breast cancer at time of enrollment * Unwillingness to provide informed consent * Unwillingness to provide biological specimen * Lack of comprehensive clinical data
Where it's running
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University General Hospital "ATTIKON", 2nd propedeutic dept. of Internal Medicine
Athens, Greece Recruiting -
"MITERA" Hospital, Dept. of Medical Oncology
Athens, Greece Recruiting -
Metropolitan Hospital, 2nd Dept. of Medical Oncology
Athens, Greece Recruiting -
Metropolitan Hospital, 4th Dept. of Medical Oncology
Athens, Greece Recruiting -
St. Luke's Hospital, Dept. of Medical Oncology
Thessaloniki, Greece Recruiting
Study contacts
- Principal investigator: Elena Fountzilas, MD, PhD — Hellenic Cooperative Oncology Group
- Study coordinator: Electra Sofou, PhD
- Email: e_sofou@hecog.ondsl.gr
- Phone: +302106912520
Similar studies
Other studies for the same condition or treatment. Recruiting studies are listed first.
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PRT13722 in advanced HR+/HER2- breast cancer
This early study tests PRT13722, by itself and with standard therapies, to see if it is safe and has any signs of activity in adults with HR+/HER2- breast cancer who have progressed on prior treatments.
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SMP-656 in HER2-positive advanced breast cancer after ADC therapy
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Entinostat with Pyrotinib and Endocrine Therapy in HER2-positive, HR-positive Advanced Breast Cancer after Trastuzumab Failure
This study tests whether adding entinostat to pyrotinib and hormone therapy is safe and helps patients with advanced HR+/HER2+ breast cancer who progressed after trastuzumab.
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T-DXd–based therapy followed by targeted HER2 blockade and endocrine therapy in first-line HER2+ / HR+ metastatic breast cancer
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How to take part
- Review the eligibility criteria above with your treating physician.
- Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
- Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.