Advanced/Metastatic HER2-negative Breast CancerNCT06975371
Real-World Outcomes of Patients With Metastatic Breast Cancer After Treatment With First-Line ET+CDK4/6i
An observational study of Advanced/Metastatic HER2-negative Breast Cancer, run by Daiichi Sankyo at 1 site in United States.
Trial summary
This study aims to assess the treatment patterns and real-world outcomes of HR+/HER- metastatic breast cancer patients who have progressed on 1L ET + CDK4/6i and started a second line (2L) treatment within a real-world cohort in the United States Flatiron Health Database. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Advanced/Metastatic HER2-negative Breast Cancer
- What is being tested?
- No drug
- How many people
- 1,415 participants
- Where
- 1 siteUnited States
- Study dates
- 14 Apr 2025to 5 Aug 2025
- Phase
- Observational
- Are there results?
- None posted in the registry
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: The study cohort consists of adults in the Flatiron database who are diagnosed with HR+/HER2- mBC and initiated a subsequent LOT (i.e., 2L) after progressing on 1L treatment with ET+CDK4/6i.
Who may be able to join
- Patients with evidence of Stage IV or recurrent mBC with a metastatic diagnosis date on or after January 1, 2017
- Aged ≥18 years at mBC diagnosis date
- Received 1L ET + CDK 4/6i, with no other systemic agents, in the metastatic setting
- Had evidence of a rwP event during 1L ET + CDK 4/6i
- Evidence of a subsequent LOT following 1L ET + CDK 4/6i (start date of subsequent LOT = index treatment date)
- A record of HR+ status in the closest estrogen receptor (ER) or progesterone receptor (PR) test result occurring prior to or within 30 days after the index treatment date
- A record of HER2- status in the closest HER2 test result recorded prior to or on the index treatment date
- Index treatment date occurring at least 90 days prior to end of study period (30Sep2024)
Who cannot join
- A record of estrogen receptor 1 (ESR1), phosphatidylinositol4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), V-akt murine thymoma viral oncogene homolog (AKT1), phosphatase and tensin homolog (PTEN), or germline breast cancer gene (gBRCA) alteration/mutation prior to or within 30 days after index treatment date
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Real-World Outcomes of Patients With HR-Positive HER2-Negative Metastatic Breast Cancer After Treatment With First-Line ET+CDK4/6i in the United States
This study aims to assess the treatment patterns and real-world outcomes of HR+/HER- metastatic breast cancer patients who have progressed on 1L ET + CDK4/6i and started a second line (2L) treatment within a real-world cohort in the United States Flatiron Health Database.
Read the detailed description
This analysis will assess real-world outcomes in HR+/HER2- mBC patients who initiated a subsequent line of therapy (LOT) (i.e., 2L) after progressing on 1L treatment with ET+CDK4/6i. This study will also characterize the treatment patterns, clinical characteristics, and outcomes in this patient population. No study drug was administered in this non-interventional study.
- Being tested
- No drug
- Keywords
- HR-positive, HER2-negative, Metastatic breast cancer
- Medical subject headings
- Breast Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
No drugOther
No study drug was administered in this non-interventional study.
| Study group | Role | What they receive |
|---|---|---|
| HR+/HER2- metastatic breast cancer | Adults in the Flatiron database who are diagnosed with HR+/HER2- metastatic breast cancer and initiated a subsequent line of therapy (i.e., 2L) after progressing on 1L treatment with ET+CDK4/6i. Receives: Other: No drug |
What is being measured
The primary outcome is the main question the study is designed to answer.
Real-world progression-free survival (rwPFS)
Real-world progression-free survival (rwPFS) will be calculated as the time from the index treatment date to the date of the first documented rwP event occurring >14 days after the index treatment date or date of death, whichever occurs first.
Measured: Baseline up to end of observation period, approximately 7 years 9 months
Secondary outcomes (3)
Real-world overall survival (rwOS)
Real-world overall survival (rwOS) will be calculated as the time from the index treatment date to death. Patients who do not experience the event of interest (death) will be censored at their last confirmed activity date.
Measured: Baseline up to end of observation period, approximately 7 years 9 months
Real-world time to discontinuation or death (rwTTD/D)
Real-world time to treatment discontinuation or death (rwTTD/D) will be calculated for the index LOT. For the set of drugs contained in the index LOT, rwTTD/D will be calculated as the time from the first drug episode to the last drug episode or death, whichever comes first.
Measured: Baseline up to end of observation period, approximately 7 years 9 months
Real-world time to next treatment or death (rwTTNT/D)
Real-world time to next treatment or death (rwTTNT/D) will be calculated for the index LOT as the time from the start of the LOT to the initiation of next LOT or death, whichever comes first.
Measured: Baseline up to end of observation period, approximately 7 years 9 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted16 May 2025
- Study start14 Apr 2025
- Primary completion8 May 2025
- Study completion5 Aug 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Advanced/Metastatic HER2-negative Breast CancerStudies of the same condition, open and under way.
- More trials run by Daiichi SankyoThe sponsor's other registered studies.
- 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
- 1,415 participants (actual)
Sponsor and investigators
- Lead sponsor
- Daiichi Sankyo
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Director, Study director, Daiichi Sankyo
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06975371
- Sponsor's protocol ID
- U31402-0012-NIS-MA
- Status last verified
- Oct 2025
- First submitted
- 9 May 2025
- Last updated
- 7 Oct 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 7 Oct 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Real-World Outcomes of Patients With HR-Positive HER2-Negative Metastatic Breast Cancer After Treatment With First-Line ET+CDK4/6i in the United States
- ClinicalTrials.gov ID
- NCT06975371
- Acronym / sponsor ID
- U31402-0012-NIS-MA
- Keywords
- HR-positive, HER2-negative, Metastatic breast cancer
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 1,415 participants (actual)
- Lead sponsor
- Daiichi SankyoIndustry (pharma, biotech, devices)
- Study start
- 14 Apr 2025 (actual)
- Primary completion
- 8 May 2025 (actual)
- Study completion
- 5 Aug 2025 (actual)
- First posted
- 16 May 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 study aims to assess the treatment patterns and real-world outcomes of HR+/HER- metastatic breast cancer patients who have progressed on 1L ET + CDK4/6i and started a second line (2L) treatment within a real-world cohort in the United States Flatiron Health Database.
Detailed description
This analysis will assess real-world outcomes in HR+/HER2- mBC patients who initiated a subsequent line of therapy (LOT) (i.e., 2L) after progressing on 1L treatment with ET+CDK4/6i. This study will also characterize the treatment patterns, clinical characteristics, and outcomes in this patient population. No study drug was administered in this non-interventional study.
Study design
- Observational model
- Cohort
- Time perspective
- Retrospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| HR+/HER2- metastatic breast cancer | – | Other: No drugAdults in the Flatiron database who are diagnosed with HR+/HER2- metastatic breast cancer and initiated a subsequent line of therapy (i.e., 2L) after progressing on 1L treatment with ET+CDK4/6i. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- The study cohort consists of adults in the Flatiron database who are diagnosed with HR+/HER2- mBC and initiated a subsequent LOT (i.e., 2L) after progressing on 1L treatment with ET+CDK4/6i.
Key inclusion criteria (8 listed)
- Patients with evidence of Stage IV or recurrent mBC with a metastatic diagnosis date on or after January 1, 2017
- Aged ≥18 years at mBC diagnosis date
- Received 1L ET + CDK 4/6i, with no other systemic agents, in the metastatic setting
- Had evidence of a rwP event during 1L ET + CDK 4/6i
- Evidence of a subsequent LOT following 1L ET + CDK 4/6i (start date of subsequent LOT = index treatment date)
Key exclusion criteria (1 listed)
- A record of estrogen receptor 1 (ESR1), phosphatidylinositol4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), V-akt murine thymoma viral oncogene homolog (AKT1), phosphatase and tensin homolog (PTEN), or germline breast cancer gene (gBRCA) alteration/mutation prior to or within 30 days after index treatment date
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| No drugNo study drug was administered in this non-interventional study. | Other | HR+/HER2- metastatic breast cancer |
Primary outcome
Real-world progression-free survival (rwPFS)
Time frame: Baseline up to end of observation period, approximately 7 years 9 months
Real-world progression-free survival (rwPFS) will be calculated as the time from the index treatment date to the date of the first documented rwP event occurring >14 days after the index treatment date or date of death, whichever occurs first.
3 secondary outcomes
Real-world overall survival (rwOS)
Time frame: Baseline up to end of observation period, approximately 7 years 9 months
Real-world time to discontinuation or death (rwTTD/D)
Time frame: Baseline up to end of observation period, approximately 7 years 9 months
Real-world time to next treatment or death (rwTTNT/D)
Time frame: Baseline up to end of observation period, approximately 7 years 9 months
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 7 Oct 2025.
- Individual participant dataSharing planned: No
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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. This study is not recruiting at the moment.
Director study director
Daiichi Sankyo
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 Advanced/Metastatic HER2-negative Breast Cancer, run by Daiichi Sankyo at 1 site in United States.
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 8 inclusion and 1 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: finished, as of the sponsor's last update on 7 Oct 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 United States. 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?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Real-world progression-free survival (rwPFS) (time frame: Baseline up to end of observation period, approximately 7 years 9 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 7 Oct 2025.