Metastatic Breast CancerNCT07073755
Real-World Study of Post-Resistance Treatment Strategies in Advanced Breast Cancer Following CDK4/6i, PIK3CA Inhibitors, or T-DXd
An observational study of Metastatic Breast Cancer and Drug Resistance, run by Hunan Cancer Hospital at 1 site in China.
Trial summary
This is a real-world observational study aiming to evaluate the effectiveness of post-progression treatment strategies in patients with advanced breast cancer who have developed resistance to prior targeted therapies, including CDK4/6 inhibitors, PIK3CA inhibitors, trastuzumab deruxtecan (T-DXd), or other targeted… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Metastatic Breast Cancer, Drug Resistance, Hormone Receptor-Positive Breast Cancer
- How many people
- 200 participants
- Where
- 1 siteChina
- Study dates
- 1 Jan 2023to 1 Jun 2026
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Patients with advanced breast cancer who developed resistance to targeted therapies and subsequently received systemic treatment in routine clinical practice. The study population includes diverse subtypes (HR+/HER2-, HER2+, TNBC) and reflects real-world treatment patterns in post-progression settings.
Who may be able to join
- Adults (≥18 years old) with histologically or cytologically confirmed advanced or metastatic breast cancer
- Received prior treatment with at least one of the following: CDK4/6 inhibitors, PIK3CA inhibitors, trastuzumab deruxtecan (T-DXd), or other targeted therapies
- Documented disease progression following prior targeted therapy
- Initiated a subsequent line of systemic therapy (chemotherapy, endocrine therapy, targeted therapy, or combination) after resistance
- Available clinical data including baseline characteristics and treatment details
- At least one follow-up evaluation after initiation of post-resistance therapy
Who cannot join
- Incomplete medical records or missing key clinical follow-up data
- Concurrent diagnosis of other active malignancies (except non-melanoma skin cancer or in situ cervical cancer)
- Known central nervous system disease requiring immediate local treatment (unless clinically stable)
- Poor general condition with an Eastern Cooperative Oncology Group (ECOG) performance status ≥2
- Life expectancy estimated to be less than 6 months based on clinical judgment
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
China1 site, 1 recruiting
- Recruiting
Hunan Cancer Hospital
Changsha, Hunan, 410013
Binliang Liu, 073189762161, liubinliang_onco@163.com
About this study
Official title: A Real-World Observational Study on Post-Resistance Treatment Outcomes in Advanced Breast Cancer Patients After CDK4/6 Inhibitors, PIK3CA Inhibitors, or Trastuzumab Deruxtecan Therapy
This is a real-world observational study aiming to evaluate the effectiveness of post-progression treatment strategies in patients with advanced breast cancer who have developed resistance to prior targeted therapies, including CDK4/6 inhibitors, PIK3CA inhibitors, trastuzumab deruxtecan (T-DXd), or other targeted agents commonly used in clinical practice. As resistance to these therapies becomes increasingly common, optimal sequencing strategies for subsequent treatment remain unclear.
This study will collect clinical information on post-resistance systemic treatments and their outcomes, including progression-free survival, overall survival, and response rate. Baseline patient and tumor characteristics will also be collected to explore potential prognostic and predictive factors and to develop outcome prediction models that may help guide future clinical decision-making.
This is a non-interventional study based on retrospective and prospective data from routine medical care. The results are expected to provide real-world evidence to inform personalized treatment strategies for patients with advanced breast cancer following resistance to targeted therapies.
Read the detailed description
Breast cancer is a heterogeneous disease, and advances in targeted therapies have significantly improved clinical outcomes, especially in hormone receptor-positive (HR+), HER2-positive, and selected triple-negative breast cancer (TNBC) subtypes. However, disease progression following treatment with targeted agents such as CDK4/6 inhibitors, PIK3CA inhibitors, and antibody-drug conjugates like trastuzumab deruxtecan (T-DXd) remains a major clinical challenge. With a growing number of post-resistance treatment options available, real-world data are urgently needed to inform evidence-based sequencing strategies in routine clinical practice.
This real-world observational study aims to investigate the treatment patterns and clinical outcomes of patients with advanced or metastatic breast cancer who experience disease progression after receiving CDK4/6 inhibitors, PIK3CA inhibitors, T-DXd, or other relevant targeted agents. The study will focus on characterizing the effectiveness of subsequent treatment regimens, including chemotherapy, endocrine therapy, additional targeted therapies, or their combinations.
In addition to evaluating clinical outcomes such as progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and duration of response (DoR), the study will collect detailed baseline patient characteristics, tumor biological features, and prior treatment histories. These data will be used to identify potential prognostic and predictive factors and to develop outcome prediction models that may support personalized treatment planning in the post-resistance setting.
Patients will be identified based on medical record review, with retrospective and/or prospective data collection depending on institutional capabilities. Treatment decisions are made at the discretion of the treating physicians as part of standard clinical care. The study does not involve any experimental intervention, and no additional diagnostic or therapeutic procedures will be imposed on participants.
The ultimate goal of this study is to generate clinically relevant, real-world evidence to guide optimal treatment sequencing after resistance to targeted therapy in advanced breast cancer, and to support future clinical research and decision-making frameworks.
- Conditions
- Metastatic Breast Cancer, Drug Resistance, Hormone Receptor-Positive Breast Cancer, HER2-positive Breast Cancer, Triple-Negative Breast Cancer (TNBC), Treatment Decisions
- Keywords
- Real-World Study, Treatment Resistance, Post-Progression Therapy, Metastatic Breast Cancer, Predictive Factors
- Medical subject headings
- Breast Neoplasms, Triple Negative Breast Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Post-Resistance Advanced Breast Cancer Patients | This cohort includes patients with advanced or metastatic breast cancer who experienced disease progression after treatment with CDK4/6 inhibitors, PIK3CA inhibitors, trastuzumab deruxtecan (T-DXd), or other targeted therapies. All patients subsequently received further systemic therapy, including chemotherapy, endocrine therapy, targeted agents, or their combinations, based on physician discretion and routine clinical practice. This observational cohort will be analyzed to assess treatment patterns, clinical outcomes (e.g., progression-free survival and overall survival), and potential prognostic or predictive factors. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Progression-Free Survival (PFS)
Progression-Free Survival (PFS) is defined as the time from the initiation of post-progression systemic treatment (after resistance to CDK4/6 inhibitors, PIK3CA inhibitors, T-DXd, or other targeted therapies) to the date of documented disease progression or death from any cause, whichever occurs first. Disease progression will be determined based on radiological or clinical assessment, as per real-world documentation standards. Patients without progression or death at the time of analysis will be censored at the date of last follow-up.
Measured: From the start of post-resistance systemic treatment until documented disease progression or death, up to 36 months.
Secondary outcomes (4)
Overall Response Rate (ORR)
ORR is defined as the proportion of patients achieving a complete response (CR) or partial response (PR) to the post-progression systemic treatment, as assessed by the treating physician based on radiological or clinical documentation. Response assessment will follow real-world clinical practice without central review.
Measured: From start of post-resistance systemic treatment to best documented response, assessed up to 24 months.
Disease Control Rate (DCR)
DCR is defined as the proportion of patients who achieve complete response (CR), partial response (PR), or stable disease (SD) for at least 8 weeks after initiating post-resistance therapy. Evaluations are based on clinical or imaging assessment as documented in routine practice.
Measured: From treatment initiation to disease progression or last follow-up, assessed up to 24 months.
Overall Survival (OS)
OS is defined as the time from the initiation of post-resistance systemic therapy to death from any cause. Patients still alive at the time of analysis will be censored at their last known follow-up date.
Measured: From start of post-progression treatment to death or last follow-up, up to 48 months.
Treatment-Related Adverse Events
The incidence and type of treatment-related adverse events (AEs) will be collected as documented in the medical record, based on physician assessment. AEs will be classified according to the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0, where available.
Measured: From the start of post-resistance treatment until 30 days after treatment discontinuation, assessed up to 24 months.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 Jul 2025
- Study start1 Jan 2023
- Primary completion30 Dec 2025 (estimated)
- Study completion1 Jun 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Metastatic Breast CancerStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Retrospective
- Enrolment
- 200 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Hunan Cancer Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07073755
- Sponsor's protocol ID
- HNCA-PoReBC
- Status last verified
- Jul 2025
- First submitted
- 9 Jul 2025
- Last updated
- 18 Jul 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 18 Jul 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Real-World Observational Study on Post-Resistance Treatment Outcomes in Advanced Breast Cancer Patients After CDK4/6 Inhibitors, PIK3CA Inhibitors, or Trastuzumab Deruxtecan Therapy
- ClinicalTrials.gov ID
- NCT07073755
- Acronym / sponsor ID
- HNCA-PoReBC
- Conditions
- Metastatic Breast Cancer, Drug Resistance, Hormone Receptor-Positive Breast Cancer, HER2-positive Breast Cancer, Triple-Negative Breast Cancer (TNBC), Treatment Decisions
- Keywords
- Real-World Study, Treatment Resistance, Post-Progression Therapy, Metastatic Breast Cancer, Predictive Factors
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 200 participants (estimated)
- Lead sponsor
- Hunan Cancer HospitalUniversity, hospital or other
- Study start
- 1 Jan 2023 (actual)
- Primary completion
- 30 Dec 2025 (estimated)
- Study completion
- 1 Jun 2026 (estimated)
- First posted
- 18 Jul 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is a real-world observational study aiming to evaluate the effectiveness of post-progression treatment strategies in patients with advanced breast cancer who have developed resistance to prior targeted therapies, including CDK4/6 inhibitors, PIK3CA inhibitors, trastuzumab deruxtecan (T-DXd), or other targeted agents commonly used in clinical practice. As resistance to these therapies becomes increasingly common, optimal sequencing strategies for subsequent treatment remain unclear.
This study will collect clinical information on post-resistance systemic treatments and their outcomes, including progression-free survival, overall survival, and response rate. Baseline patient and tumor characteristics will also be collected to explore potential prognostic and predictive factors and to develop outcome prediction models that may help guide future clinical decision-making.
This is a non-interventional study based on retrospective and prospective data from routine medical care. The results are expected to provide real-world evidence to inform personalized treatment strategies for patients with advanced breast cancer following resistance to targeted therapies.
Detailed description
Breast cancer is a heterogeneous disease, and advances in targeted therapies have significantly improved clinical outcomes, especially in hormone receptor-positive (HR+), HER2-positive, and selected triple-negative breast cancer (TNBC) subtypes. However, disease progression following treatment with targeted agents such as CDK4/6 inhibitors, PIK3CA inhibitors, and antibody-drug conjugates like trastuzumab deruxtecan (T-DXd) remains a major clinical challenge. With a growing number of post-resistance treatment options available, real-world data are urgently needed to inform evidence-based sequencing strategies in routine clinical practice.
This real-world observational study aims to investigate the treatment patterns and clinical outcomes of patients with advanced or metastatic breast cancer who experience disease progression after receiving CDK4/6 inhibitors, PIK3CA inhibitors, T-DXd, or other relevant targeted agents. The study will focus on characterizing the effectiveness of subsequent treatment regimens, including chemotherapy, endocrine therapy, additional targeted therapies, or their combinations.
In addition to evaluating clinical outcomes such as progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and duration of response (DoR), the study will collect detailed baseline patient characteristics, tumor biological features, and prior treatment histories. These data will be used to identify potential prognostic and predictive factors and to develop outcome prediction models that may support personalized treatment planning in the post-resistance setting.
Patients will be identified based on medical record review, with retrospective and/or prospective data collection depending on institutional capabilities. Treatment decisions are made at the discretion of the treating physicians as part of standard clinical care. The study does not involve any experimental intervention, and no additional diagnostic or therapeutic procedures will be imposed on participants.
The ultimate goal of this study is to generate clinically relevant, real-world evidence to guide optimal treatment sequencing after resistance to targeted therapy in advanced breast cancer, and to support future clinical research and decision-making frameworks.
Study design
- Observational model
- Cohort
- Time perspective
- Retrospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Post-Resistance Advanced Breast Cancer Patients | – | –This cohort includes patients with advanced or metastatic breast cancer who experienced disease progression after treatment with CDK4/6 inhibitors, PIK3CA inhibitors, trastuzumab deruxtecan (T-DXd), or other targeted therapies. All patients subsequently received further systemic therapy, including chemotherapy, endocrine therapy, targeted agents, or their combinations, based on physician discretion and routine clinical practice. This observational cohort will be analyzed to assess treatment patterns, clinical outcomes (e.g., progression-free survival and overall survival), and potential prognostic or predictive factors. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Patients with advanced breast cancer who developed resistance to targeted therapies and subsequently received systemic treatment in routine clinical practice. The study population includes diverse subtypes (HR+/HER2-, HER2+, TNBC) and reflects real-world treatment patterns in post-progression settings.
Key inclusion criteria (6 listed)
- Adults (≥18 years old) with histologically or cytologically confirmed advanced or metastatic breast cancer
- Received prior treatment with at least one of the following: CDK4/6 inhibitors, PIK3CA inhibitors, trastuzumab deruxtecan (T-DXd), or other targeted therapies
- Documented disease progression following prior targeted therapy
- Initiated a subsequent line of systemic therapy (chemotherapy, endocrine therapy, targeted therapy, or combination) after resistance
- Available clinical data including baseline characteristics and treatment details
Key exclusion criteria (5 listed)
- Incomplete medical records or missing key clinical follow-up data
- Concurrent diagnosis of other active malignancies (except non-melanoma skin cancer or in situ cervical cancer)
- Known central nervous system disease requiring immediate local treatment (unless clinically stable)
- Poor general condition with an Eastern Cooperative Oncology Group (ECOG) performance status ≥2
- Life expectancy estimated to be less than 6 months based on clinical judgment
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Progression-Free Survival (PFS)
Time frame: From the start of post-resistance systemic treatment until documented disease progression or death, up to 36 months.
Progression-Free Survival (PFS) is defined as the time from the initiation of post-progression systemic treatment (after resistance to CDK4/6 inhibitors, PIK3CA inhibitors, T-DXd, or other targeted therapies) to the date of documented disease progression or death from any cause, whichever occurs first. Disease progression will be determined based on radiological or clinical assessment, as per real-world documentation standards. Patients without progression or death at the time of analysis will be censored at the date of last follow-up.
4 secondary outcomes
Overall Response Rate (ORR)
Time frame: From start of post-resistance systemic treatment to best documented response, assessed up to 24 months.
Disease Control Rate (DCR)
Time frame: From treatment initiation to disease progression or last follow-up, assessed up to 24 months.
Overall Survival (OS)
Time frame: From start of post-progression treatment to death or last follow-up, up to 48 months.
Treatment-Related Adverse Events
Time frame: From the start of post-resistance treatment until 30 days after treatment discontinuation, assessed up to 24 months.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Jul 2025.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Metastatic Breast Cancer and Drug Resistance, run by Hunan Cancer Hospital at 1 site in China.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 18 Jul 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in China. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Binliang Liu, M.D (+8617370789834, liubinliang_onco@163.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Progression-Free Survival (PFS) (time frame: From the start of post-resistance systemic treatment until documented disease progression or death, up to 36 months.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Jul 2025.