Trial Outcomes & Findings for A Study of HR+/HER2- Metastatic Breast Cancer Patients Treated With Palbociclib Together With an Aromatase Inhibitor From 2017 to 2023 in Denmark. (NCT NCT06307457)

NCT ID: NCT06307457

Last Updated: 2025-06-29

Results Overview

PFS was defined as the time from the index date to progression or death, whichever occurred first. Progression of disease was based on scans and blood testing results. Disease progression was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (this includes the baseline sum if that is the smallest on study). In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 millimeters (mm). Index date was date of relapse or stage IV disease. Stage IV disease means that the cancer has spread to distant parts of the body. Kaplan-Meier method was used for analysis.

Recruitment status

COMPLETED

Target enrollment

604 participants

Primary outcome timeframe

From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Results posted on

2025-06-29

Participant Flow

Participants diagnosed with hormone receptor positive (HR+) or human epidermal growth factor receptor (HER2) metastatic breast cancer (mBC) who initiated treatment with palbociclib in combination with aromatase inhibitor (AI) as first line treatment between 1 January 2017 to 31 December 2021 were observed.

Data collected retrospectively from 1 January 2017 to 1 February 2024 from Danish Breast Cancer Group (DBCG) registry and was evaluated for approximately 1.3 months (duration from start of the study to end of the study) in this retrospective study.

Participant milestones

Participant milestones
Measure
All Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
Overall Study
STARTED
604
Overall Study
COMPLETED
604
Overall Study
NOT COMPLETED
0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Race and Ethnicity were not collected from any participant.

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
Age, Continuous
66.8 Years
STANDARD_DEVIATION 10.9 • n=604 Participants
Sex: Female, Male
Female
604 Participants
n=604 Participants
Sex: Female, Male
Male
0 Participants
n=604 Participants

PRIMARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study.

PFS was defined as the time from the index date to progression or death, whichever occurred first. Progression of disease was based on scans and blood testing results. Disease progression was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (this includes the baseline sum if that is the smallest on study). In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 millimeters (mm). Index date was date of relapse or stage IV disease. Stage IV disease means that the cancer has spread to distant parts of the body. Kaplan-Meier method was used for analysis.

Outcome measures

Outcome measures
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
Progression-Free Survival (PFS)
30.6 Months
Interval 27.4 to 34.2

PRIMARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study.

OS was defined as the time from date of relapse or stage IV disease (index date) to death at any cause. Participants were censored for OS by 1 February 2024. Index date was the date of relapse or stage IV disease. Stage IV disease means that the cancer has spread to distant parts of the body.

Outcome measures

Outcome measures
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
Overall Survival (OS)
55.6 Months
Interval 51.8 to 58.9

SECONDARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study. All participants under "Overall Number of Participants Analyzed" contributed data to the table but may not have data evaluable for every row and "Number Analyzed" signifies participants evaluable for specified rows.

PFS was defined as the time from the index date to progression or death, whichever occurred first. Progression of disease was based on scans and blood testing results. Disease progression was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (this includes the baseline sum if that is the smallest on study). In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. Kaplan-Meier method was used for analysis. PFS per age category (\< 65 years, 65-75 years and \> 75 years) were reported in this outcome measure. Index date was the date of relapse or stage IV disease. Stage IV disease means that the cancer has spread to distant parts of the body.

Outcome measures

Outcome measures
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
PFS Based on Age of Participants
For participants aged < 65 years
25.8 Months
Interval 22.2 to 30.7
PFS Based on Age of Participants
For participants aged between 65-75 years
35.7 Months
Interval 30.4 to 42.2
PFS Based on Age of Participants
For participants aged > 75 years
29.8 Months
Interval 23.6 to 37.2

SECONDARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study. All participants under "Overall Number of Participants Analyzed" contributed data to the table but may not have data evaluable for every row and "Number Analyzed" signifies participants evaluable for specified rows.

OS was defined as the time from date of relapse or stage IV disease (index date) to death at any cause. Participants were censored for OS by 1 February 2024. OS per age category such as \< 65 years, 65-75 years and \>75 years were reported in this outcome measure. Index date was the date of relapse or stage IV disease. Stage IV disease means that the cancer has spread to distant parts of the body.

Outcome measures

Outcome measures
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
OS Based on Age of Participants
For participants aged <65 years
52.6 Months
Interval 48.6 to 59.2
OS Based on Age of Participants
For participants aged between 65-75 years
60.8 Months
Interval 55.6 to 78.3
OS Based on Age of Participants
For participants aged >75 years
50.1 Months
Interval 41.4 to 58.6

SECONDARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study. All participants under "Overall Number of Participants Analyzed" contributed data to the table but may not have data evaluable for every row and "Number Analyzed" signifies participants evaluable for specified rows.

PFS was defined as the time from the index date to progression or death, whichever occurred first. CCI was used as data source for comorbidity. Each comorbidity recorded for participant, had score between 0 to 6 as per comorbidity burden, if it was part of CCI. Higher score=more severe comorbidity status. CCI score 0:participants with no comorbidity besides BC disease, CCI score 1:participant with one comorbidity with score of 1,e.g.,myocardial infarction or diabetes mellitus(DM), CCI score 2:participant with two comorbidities each classified with score of 1 or one single comorbidity classified with score of 2,e.g.,DM with organ damage, CCI score of 3or higher: participant with severe comorbidity, i.e. those having one comorbidity classified with score of 6(e.g., Human Immunodeficiency Virus/Acquired Immuno Deficiency Syndrome),or two or more comorbidities each classified with scores of1-2,all in addition to participant's BC disease. Index date=date of relapse or stage IV disease.

Outcome measures

Outcome measures
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
PFS Per Charlson Comorbidity Index (CCI) Score
For participants with CCI score 0
32.8 Months
Interval 28.3 to 36.7
PFS Per Charlson Comorbidity Index (CCI) Score
For participants with CCI score 1
32.0 Months
Interval 26.0 to 45.8
PFS Per Charlson Comorbidity Index (CCI) Score
For participants with CCI score 2
29.7 Months
Interval 17.1 to 38.3
PFS Per Charlson Comorbidity Index (CCI) Score
For participants with CCI score 3+
21.5 Months
Interval 18.0 to 33.2

SECONDARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study. All participants under "Overall Number of Participants Analyzed" contributed data to the table but may not have data evaluable for every row and "Number Analyzed" signifies participants evaluable for specified rows.

OS: time from date of relapse or stage IV disease to death at any cause. CCI was used as data source for comorbidity in study. For each comorbidity recorded for participant score between 0 to 6 was assigned based on comorbidity burden, whether it was part of CCI.Higher score=more severe comorbidity status.CCI scores: CCI score 0:participants with no comorbidity besides BC disease, CCI score 1:participant with one comorbidity with score of 1,e.g., myocardial infarction or DM,CCI score 2:participant with two comorbidities each classified with score of 1 or one single comorbidity classified with score of 2,e.g.,DM with organ damage, CCI score of 3 or higher: participant with severe comorbidity,i.e.those having one comorbidity classified with score of 6(e.g., Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome),or two or more comorbidities each classified with scores of 1-2,all in addition to participant's BC disease. Index date=date of relapse or stage IV disease.

Outcome measures

Outcome measures
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
OS Per CCI Score
For participants with CCI score 0
57.6 Months
Interval 53.9 to 66.7
OS Per CCI Score
For participants with CCI score 1
50.1 Months
Interval 43.6 to 58.9
OS Per CCI Score
For participants with CCI score 2
53.1 Months
Interval 43.3 to
Upper limit of 95% CI was not estimable due to insufficient number of participants with event.
OS Per CCI Score
For participants with CCI score 3+
45.2 Months
Interval 37.7 to 58.3

SECONDARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study. All participants under "Overall Number of Participants Analyzed" contributed data to the table but may not have data evaluable for every row and "Number Analyzed" signifies participants evaluable for specified rows.

PFS was defined as the time from the index date to progression or death, whichever occurred first. Participants were censored for PFS by 1 February 2024. Progression was based on radiological, clinical, and biochemical examination from the treating departments. Participants were split into three comorbidity groups - no comorbidity (0), one comorbidity and two or more comorbidities. Comorbidities included myocardial infarction, congestive heart failure (CHF), peripheral vascular disease, cerebrovascular disease, dementia, chronic pulmonary disease, connective tissue disease, ulcer disease, mild liver disease, DM, hemiplegia, moderate-severe renal disease, DM with end organ damage, any tumor, leukemia, lymphoma, moderate-severe liver disease, metastatic solid tumor and acquired immune deficiency syndrome/human immune virus (AIDS/HIV). Index date was the date of relapse or stage IV disease.

Outcome measures

Outcome measures
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
PFS Per Number of Comorbidities
For participants with 0 comorbidity
32.8 Months
Interval 28.3 to 36.7
PFS Per Number of Comorbidities
For participants with 1 comorbidity
27.9 Months
Interval 23.8 to 37.9
PFS Per Number of Comorbidities
For participants with 2+ comorbidities
23.6 Months
Interval 19.3 to 35.6

SECONDARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study. All participants under "Overall Number of Participants Analyzed" contributed data to the table but may not have data evaluable for every row and "Number Analyzed" signifies participants evaluable for specified rows.

OS was defined as the time from date of relapse or stage IV disease (index date) to death at any cause. Participants were split into three comorbidity groups - no comorbidity (0), one comorbidity and two or more comorbidities. Comorbidities included myocardial infarction, CHF, peripheral vascular disease, cerebrovascular disease, dementia, chronic pulmonary disease, connective tissue disease, ulcer disease, mild liver disease, DM, hemiplegia, moderate-severe renal disease, DM with end organ damage, any tumor, leukemia, lymphoma, moderate-severe liver disease, metastatic solid tumor and AIDS/HIV. Index date was the date of relapse or stage IV disease.

Outcome measures

Outcome measures
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
OS Per Number of Comorbidities
For participants with 0 comorbidity
57.6 Months
Interval 53.9 to 66.7
OS Per Number of Comorbidities
For participants with 1 comorbidity
50.1 Months
Interval 44.5 to 58.0
OS Per Number of Comorbidities
For participants with 2+ comorbidities
52.7 Months
Interval 41.2 to
Upper limit of 95% CI was not estimable due to insufficient number of participants with event.

SECONDARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study. All participants under "Overall Number of Participants Analyzed" signifies participants evaluable for this outcome measure and "Number Analyzed" signifies participants evaluable for specified rows.

PFS was defined as the time from the index date to progression or death, whichever occurred first. Participants were censored for PFS by 1 February 2024. Progression was based on radiological, clinical, and biochemical examination from the treating departments. Comorbidities were categorized into five main disease groups: cardiac disease, vascular disease, metabolic disease, psychiatric disease and blood and lymphatic system. Results for cardiac disease, vascular disease and metabolic disease have been reported in this outcome measure. Index date was the date of relapse or stage IV disease. Stage IV disease means that the cancer has spread to distant parts of the body.

Outcome measures

Outcome measures
Measure
All Participants
n=113 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
PFS Per Type of Comorbidity
For participants with cardiac disease
27.9 Months
Interval 22.2 to
Upper limit of 95% CI was not estimable due to insufficient number of participants with event.
PFS Per Type of Comorbidity
For participants with vascular disease
32.3 Months
Interval 22.9 to 44.9
PFS Per Type of Comorbidity
For participants with metabolic disease
25.5 Months
Interval 17.7 to 36.5

SECONDARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study. All participants under "Overall Number of Participants Analyzed" signifies participants evaluable for this outcome measure and "Number Analyzed" signifies participants evaluable for specified rows.

OS was defined as the time from date of relapse or stage IV disease (index date) to death at any cause. Comorbidities were categorized into five main disease groups: Cardiac disease, vascular disease, metabolic disease, psychiatric disease and blood and lymphatic system. Results for cardiac disease, vascular disease and metabolic disease have been reported in this outcome measure. Index date was the date of relapse or stage IV disease.

Outcome measures

Outcome measures
Measure
All Participants
n=113 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
OS Per Type of Comorbidity
For participants with cardiac disease
61.2 Months
Interval 45.6 to
Upper limit of 95% CI was not estimable due to insufficient number of participants with event.
OS Per Type of Comorbidity
For participants with vascular disease
47.4 Months
Interval 42.9 to
Upper limit of 95% CI was not estimable due to insufficient number of participants with event.
OS Per Type of Comorbidity
For participants with metabolic disease
50.1 Months
Interval 39.8 to
Upper limit of 95% CI was not estimable due to insufficient number of participants with event.

SECONDARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study. All participants under "Overall Number of Participants Analyzed" contributed data to the table but may not have data evaluable for every row and "Number Analyzed" signifies participants evaluable for specified rows.

PFS was defined as the time from the index date to progression or death, whichever occurred first. Participants were censored for PFS by 1 February 2024. Progression was based on radiological, clinical, and biochemical examination from the treating departments. Visceral disease status was defined as metastases in the visceral organs, e.g., lung, liver. Non-visceral disease status was defined as metastases in the non-visceral organs, e.g., bone, skin, lymph nodes. PFS in participants with visceral and non-visceral disease status is reported in this outcome measure. Index date was the date of relapse or stage IV disease. Stage IV disease means that the cancer has spread to distant parts of the body.

Outcome measures

Outcome measures
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
PFS Per Visceral Disease Status
Participants with non-visceral disease status
34.6 Months
Interval 31.1 to 39.8
PFS Per Visceral Disease Status
Participants with visceral disease status
24.2 Months
Interval 19.8 to 30.3

SECONDARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study. All participants under "Overall Number of Participants Analyzed" contributed data to the table but may not have data evaluable for every row and "Number Analyzed" signifies participants evaluable for specified rows.

OS was defined as the time from date of relapse or stage IV disease (index date) to death at any cause. Visceral disease status was defined as metastases in the organs, e.g., lung, liver. Non-visceral disease status was defined as metastases in the non-visceral organs, e.g., bone, skin, lymph nodes. OS per visceral disease status was reported as visceral and non-visceral disease status in this outcome measure. Index date was the date of relapse or stage IV disease.

Outcome measures

Outcome measures
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
OS Per Visceral Disease Status
Participants with non-visceral disease status
59.2 Months
Interval 56.6 to 69.8
OS Per Visceral Disease Status
Participants with visceral disease status
50.6 Months
Interval 44.0 to 55.7

SECONDARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study. All participants under "Overall Number of Participants Analyzed" contributed data to the table but may not have data evaluable for every row and "Number Analyzed" signifies participants evaluable for specified rows.

PFS was defined as the time from the index date to progression or death, whichever occurred first. Participants were censored for PFS by 1 February 2024. Progression was based on radiological, clinical, and biochemical examination from the treating departments. PFS was reported in participants with bone only (metastasis within bones) and non-bone only (metastasis within organs excluding bones) disease status in this outcome measure. Index date was the date of relapse or stage IV disease. Stage IV disease means that the cancer has spread to distant parts of the body.

Outcome measures

Outcome measures
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
PFS Per Bone Disease Status
Participants with bone only disease status
34.6 Months
Interval 27.7 to 42.6
PFS Per Bone Disease Status
Participants with non-bone only disease status
29.0 Months
Interval 25.4 to 33.1

SECONDARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study. All participants under "Overall Number of Participants Analyzed" contributed data to the table but may not have data evaluable for every row and "Number Analyzed" signifies participants evaluable for specified rows.

OS was defined as the time from date of relapse or stage IV disease (index date) to death at any cause. OS was reported in participants with bone only (metastasis within bones) and non-bone only (metastasis within organs excluding bones) disease status in this outcome measure. Index date was the date of relapse or stage IV disease.

Outcome measures

Outcome measures
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
OS Per Bone Disease Status
Participants with bone only disease status
58.3 Months
Interval 51.8 to
Upper limit of 95% CI was not estimable due to insufficient number of participants with event.
OS Per Bone Disease Status
Participants with non-bone only disease status
54.2 Months
Interval 50.1 to 58.6

SECONDARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study. All participants under "Overall Number of Participants Analyzed" contributed data to the table but may not have data evaluable for every row and "Number Analyzed" signifies participants evaluable for specified rows.

PFS was defined as the time from the index date to progression or death, whichever occurred first. Participants were censored for PFS by 1 February 2024. Progression was based on radiological, clinical, and biochemical examination from the treating departments. Endocrine resistant participants were defined as recurrent participants with advanced disease within 12 months of completing adjuvant endocrine therapy or during adjuvant endocrine therapy. Endocrine sensitive participants were defined as recurrent participants with advanced disease after 12 months of completing adjuvant endocrine therapy, recurrent participants who received no adjuvant endocrine therapy or participants with de novo, advanced breast cancer. De novo participants were defined as newly metastatic participants. Index date was the date of relapse or stage IV disease.

Outcome measures

Outcome measures
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
PFS Per Endocrine Status
Participants with endocrine resistant status
21.7 Months
Interval 13.8 to 37.2
PFS Per Endocrine Status
Participants with endocrine sensitive status
31.8 Months
Interval 28.5 to 34.6
PFS Per Endocrine Status
Participants with de novo metastatic status
32.0 Months
Interval 25.5 to 43.3

SECONDARY outcome

Timeframe: From index date to disease progression or death or censoring date, whichever occurred first (data collected from 1 January 2017 to 1 February 2024 [maximum up to 7.09 years] and observed retrospectively for approximately 1.3 months of this study)

Population: Analysis population included all eligible participants whose data were retrieved and observed in the study. All participants under "Overall Number of Participants Analyzed" contributed data to the table but may not have data evaluable for every row and "Number Analyzed" signifies participants evaluable for specified rows.

OS was defined as the time from date of relapse or stage IV disease (index date) to death at any cause. OS per endocrine status was reported in participants with endocrine resistant, endocrine sensitive and de novo metastatic status in this outcome measure. Endocrine resistant participants were defined as recurrent participants with advanced disease within 12 months of completing adjuvant endocrine therapy or during adjuvant endocrine therapy. Endocrine sensitive participants were defined as recurrent participants with advanced disease after 12 months of completing adjuvant endocrine therapy, recurrent participants who received no adjuvant endocrine therapy or participants with de novo, advanced breast cancer. De novo participants were defined as newly metastatic participants. Index date was the date of relapse or stage IV disease.

Outcome measures

Outcome measures
Measure
All Participants
n=604 Participants
Participants with HR+/HER2 mBC who initiated treatment with palbociclib as first line in combination with AI between 01 January 2017 and 31 December 2021 was observed retrospectively for approximately 1.3 months in this study.
OS Per Endocrine Status
Participants with endocrine resistant status
43.5 Months
Interval 32.2 to 59.2
OS Per Endocrine Status
Participants with endocrine sensitive status
56.6 Months
Interval 52.6 to 60.8
OS Per Endocrine Status
Participants with de novo metastatic status
58.9 Months
Interval 52.6 to 70.3

Adverse Events

All Participants

Serious events: 0 serious events
Other events: 0 other events
Deaths: 322 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Pfizer ClinicalTrials.gov Call Center

Pfizer Inc.

Phone: 1-800-718-1021

Results disclosure agreements

  • Principal investigator is a sponsor employee Pfizer has the right to review disclosures, requesting a delay of less than 60 days. Investigator will postpone single center publications until after disclosure of pooled data (all sites), less than 12 months from study completion/termination at all participating sites. Investigator may not disclose previously undisclosed confidential information other than study results.
  • Publication restrictions are in place

Restriction type: OTHER