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Study Evaluating Bosutinib-Letrozole Combination Versus Letrozole Alone In Post Menopausal Women With Breast Cancer

A PHASE 2, RANDOMIZED, OPEN-LABEL STUDY OF BOSUTINIB ADMINISTERED IN COMBINATION WITH LETROZOLE VS. LETROZOLE ALONE AS FIRST LINE THERAPY IN POST-MENOPAUSAL WOMEN WITH LOCALLY ADVANCED OR METASTATIC ER+/PR+/HER2- BREAST CANCER.

Status
Terminated
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00880009
Enrollment
16
Registered
2009-04-13
Start date
2009-07-30
Completion date
2010-05-31
Last updated
2021-09-27

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Breast Cancer

Brief summary

This is a phase 2 study of bosutinib administered in combination with letrozole versus letrozole alone in post-menopausal women with breast cancer. This is a 2-part study. Subjects in part 1 will receive bosutinib and letrozole daily, and will be closely monitored for 28 days. The second part will proceed with subjects receiving a dose that is determined to be safe based on the safety evaluation of the first part. Eligible subjects will be randomly assigned to receive either bosutinib daily combined with daily letrozole, or daily letrozole alone for a specified period of time. Subjects will be followed up for survival after study drug discontinuation.

Detailed description

This study was terminated on 19 April 2009 due to unfavorable risk benefit ratio of Bosutinib in combination with Letrozole including one confirmed Hy's law case. 37.5% of patients had treatment related liver events with the majority of severe events resulting in permanent study treatment discontinuation.

Interventions

DRUGBosutinib

400mg (4x100)mg tablets once daily during the active phase of treatment until Disease Progression, unacceptable toxicity or withdraw of consents occurs

DRUGLetrozole

2.5 mg - one tablet per day- once daily during the active phase of treatment until Disease Progression, unacceptable toxicity or withdraw of consents occurs

Sponsors

Pfizer
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Surgically sterile or post-menopausal women. * Confirmed pathologic diagnosis of breast cancer. * Locally advanced or metastatic, or loco-regional recurrent breast cancer not amenable to curative treatment with surgery or radiotherapy. * Documented ER+ and/or PgR+ and erbB2- tumor based on most recently analyzed biopsy, as documented by a local laboratory. * At least 1 radiologically measurable lesion as defined by Response Evaluation Criteria in Solid Tumors (RECIST). * Eastern Cooperative Oncology Group (ECOG) performance status 0-2.

Exclusion criteria

* Prior letrozole (except in adjuvant setting), prior bosutinib, or any other prior Src inhibitor. * Prior endocrine treatment for locally advanced or metastatic breast cancer (up to one prior adjuvant Aromatase Inhibitor (AI) agent/regimen is permitted). * More than 1 prior chemotherapy regimen in locally advanced or metastatic breast cancer. * Adjuvant endocrine therapy \<=12 months prior to day 1 of treatment. * Disease refractory (ie, Progressive disease (PD) within 6 months from initiation of therapy) to previous adjuvant antiestrogen therapy. * Bone or skin as the only site of disease. * Extensive visceral disease or active Central Nervous System (CNS) disease. * Any other cancer within 5 years of screening with the exception of ER+ contralateral breast carcinoma, adequately treated cervical carcinoma in situ, or adequately treated basal or squamous cell carcinoma of the skin. * Major surgery or radiotherapy within 14 days of treatment day. * Inadequate hepatic/renal/bone marrow function. * History of clinically significant or uncontrolled cardiac disease. * Serious concurrent illness.

Design outcomes

Primary

MeasureTime frameDescription
Progression-Free Survival (PFS) Based on Independent RadiologistPart 2 Baseline, every 8 weeks up to 2 to 6 weeks after last doseTime in weeks from date of randomization to first documentation of objective tumor progression or death due to any cause. PFS: calculated as (first event date minus the date of randomization plus 1) divided by 7. Tumor progression: determined from oncologic assessment data (where data meet the criteria for progressive disease \[PD\]), or from adverse event (AE) data (where the outcome was Death). PFS assessed by independent radiologist was to be reported.

Secondary

MeasureTime frameDescription
Progression-Free Survival (PFS) Based on InvestigatorPart 2 Baseline, every 8 weeks up to 2 to 6 weeks after last doseTime in weeks from date of randomization to first documentation of objective tumor progression or death due to any cause. PFS: calculated as (first event date minus the date of randomization plus 1) divided by 7. Tumor progression: determined from oncologic assessment data (where data meet the criteria for PD), or from AE data (where the outcome was Death). PFS assessed by investigator was to be reported.
Percentage of Participants With Objective ResponsePart 2 Baseline, every 8 weeks up to 2 to 6 weeks after last dosePercentage of participants with objective response based on assessment of confirmed complete response (CR) or confirmed partial response (PR) according to Response Evaluation Criteria in Solid Tumors (RECIST). Confirmed CR defined as disappearance of all target lesions. Confirmed PR defined as greater than or equal to \>=30 percent (%) decrease in sum of the longest dimensions (LD) of the target lesions taking as a reference the baseline sum LD according to RECIST. Confirmed responses are those that persist on repeat imaging study \>=4 weeks after initial documentation of response.
Overall Survival (OS)Part 2 Baseline until death or up to 36 monthsTime in weeks from randomization to date of death due to any cause. OS was calculated as (the death date minus the date of randomization plus 1) divided by 7. Death was determined from adverse event data (where outcome was death) or from follow-up contact data (where the participant current status was death).
Duration of Response (DR)Part 2 Baseline, every 8 weeks up to 2 to 6 weeks after last doseTime in weeks from the first documentation of objective tumor response to objective tumor progression or death due to any cancer. Duration of tumor response was calculated as (the date of the first documentation of objective tumor progression or death due to cancer minus the date of the first CR or PR that was subsequently confirmed plus 1) divided by 7. DR was calculated for the subgroup of participants with a confirmed objective tumor response.
Percentage of Participants With Treatment-Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)Part 1 Baseline up to 28 days after the last doseAn AE was any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. An SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly. Treatment-emergent are events between first dose of study drug and up to 28 days after last dose that were absent before treatment or that worsened relative to pretreatment state.
Maximum Observed Plasma Concentration (Cmax)0 hour (pre-dose) on Day 1; 2, 3, 4, 6, 8, 24 hours post-dose on Day 29
Time to Reach Maximum Observed Plasma Concentration (Tmax)0 hour (pre-dose) on Day 1; 2, 3, 4, 6, 8, 24 hours post-dose on Day 29
Area Under the Curve From Time Zero to Last Quantifiable Concentration [AUC (0-24)]0 hour (pre-dose) on Day 1; 2, 3, 4, 6, 8, 24 hours post-dose on Day 29AUC (0-24)= Area under the plasma concentration versus time curve from time zero (pre-dose) to time of last quantifiable concentration (0-24).
Functional Assessment of Cancer Therapy-Breast Cancer (FACT-B)Part 2 Baseline, Week 12, 24, 52, 2-6 weeks after the last doseFACT-B is used for assessment of health-related quality of life (QoL) in participants with breast cancer. It consists of 36 items, summarized to 5 subscales: physical (7 items), functional (7 items), social/family (7 items); all 3 ranged from 0 to 28, emotional (6 items) ranging from 0 to 24, and additional concerns on breast cancer subscale (9 items) ranging from 0 to 36; high subscale score represents a better QoL. All single-item measures ranges from 0='Not at all' to 4='Very much'. Total possible score ranged from 0 to 144. High scale score represents a better QoL.

Countries

Belgium, China, Hong Kong, Hungary, Poland, Singapore, United States

Participant flow

Pre-assignment details

Study was pre-maturely terminated after part 1 (safety lead-in phase) of the study and hence, the planned treatments of part 2, bosutinib + letrozole (Part 2) and letrozole (Part 2), were not administered.

Participants by arm

ArmCount
Bosutinib + Letrozole (Part 1)
Four bosutinib 100 milligram (mg) tablets, equivalent to 400 mg bosutinib along with letrozole 2.5 mg tablet orally once daily until disease progression, unacceptable toxicity or withdrawal of consent occurred.
16
Total16

Withdrawals & dropouts

PeriodReasonFG000
Overall StudyProtocol Violation1
Overall StudyStudy terminated by sponsor14
Overall StudyWithdrawal by Subject1

Baseline characteristics

CharacteristicBosutinib + Letrozole (Part 1)
Age, Continuous59.6 years
STANDARD_DEVIATION 9.78
Sex: Female, Male
Female
16 Participants
Sex: Female, Male
Male
0 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
— / —
other
Total, other adverse events
16 / 16
serious
Total, serious adverse events
5 / 16

Outcome results

Primary

Progression-Free Survival (PFS) Based on Independent Radiologist

Time in weeks from date of randomization to first documentation of objective tumor progression or death due to any cause. PFS: calculated as (first event date minus the date of randomization plus 1) divided by 7. Tumor progression: determined from oncologic assessment data (where data meet the criteria for progressive disease \[PD\]), or from adverse event (AE) data (where the outcome was Death). PFS assessed by independent radiologist was to be reported.

Time frame: Part 2 Baseline, every 8 weeks up to 2 to 6 weeks after last dose

Population: Data were not analyzed because the study was prematurely terminated due to unfavorable risk benefit ratio of the study treatment.

Secondary

Area Under the Curve From Time Zero to Last Quantifiable Concentration [AUC (0-24)]

AUC (0-24)= Area under the plasma concentration versus time curve from time zero (pre-dose) to time of last quantifiable concentration (0-24).

Time frame: 0 hour (pre-dose) on Day 1; 2, 3, 4, 6, 8, 24 hours post-dose on Day 29

Population: Data were not analyzed because the study was prematurely terminated due to unfavorable risk benefit ratio of the study treatment.

Secondary

Duration of Response (DR)

Time in weeks from the first documentation of objective tumor response to objective tumor progression or death due to any cancer. Duration of tumor response was calculated as (the date of the first documentation of objective tumor progression or death due to cancer minus the date of the first CR or PR that was subsequently confirmed plus 1) divided by 7. DR was calculated for the subgroup of participants with a confirmed objective tumor response.

Time frame: Part 2 Baseline, every 8 weeks up to 2 to 6 weeks after last dose

Population: Data were not analyzed because the study was prematurely terminated due to unfavorable risk benefit ratio of the study treatment.

Secondary

Functional Assessment of Cancer Therapy-Breast Cancer (FACT-B)

FACT-B is used for assessment of health-related quality of life (QoL) in participants with breast cancer. It consists of 36 items, summarized to 5 subscales: physical (7 items), functional (7 items), social/family (7 items); all 3 ranged from 0 to 28, emotional (6 items) ranging from 0 to 24, and additional concerns on breast cancer subscale (9 items) ranging from 0 to 36; high subscale score represents a better QoL. All single-item measures ranges from 0='Not at all' to 4='Very much'. Total possible score ranged from 0 to 144. High scale score represents a better QoL.

Time frame: Part 2 Baseline, Week 12, 24, 52, 2-6 weeks after the last dose

Population: Data were not analyzed because the study was prematurely terminated due to unfavorable risk benefit ratio of the study treatment.

Secondary

Maximum Observed Plasma Concentration (Cmax)

Time frame: 0 hour (pre-dose) on Day 1; 2, 3, 4, 6, 8, 24 hours post-dose on Day 29

Population: Data were not analyzed because the study was prematurely terminated due to unfavorable risk benefit ratio of the study treatment.

Secondary

Overall Survival (OS)

Time in weeks from randomization to date of death due to any cause. OS was calculated as (the death date minus the date of randomization plus 1) divided by 7. Death was determined from adverse event data (where outcome was death) or from follow-up contact data (where the participant current status was death).

Time frame: Part 2 Baseline until death or up to 36 months

Population: Data were not analyzed because the study was prematurely terminated due to unfavorable risk benefit ratio of the study treatment.

Secondary

Percentage of Participants With Objective Response

Percentage of participants with objective response based on assessment of confirmed complete response (CR) or confirmed partial response (PR) according to Response Evaluation Criteria in Solid Tumors (RECIST). Confirmed CR defined as disappearance of all target lesions. Confirmed PR defined as greater than or equal to \>=30 percent (%) decrease in sum of the longest dimensions (LD) of the target lesions taking as a reference the baseline sum LD according to RECIST. Confirmed responses are those that persist on repeat imaging study \>=4 weeks after initial documentation of response.

Time frame: Part 2 Baseline, every 8 weeks up to 2 to 6 weeks after last dose

Population: Data were not analyzed because the study was prematurely terminated due to unfavorable risk benefit ratio of the study treatment.

Secondary

Percentage of Participants With Treatment-Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)

An AE was any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. An SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly. Treatment-emergent are events between first dose of study drug and up to 28 days after last dose that were absent before treatment or that worsened relative to pretreatment state.

Time frame: Part 1 Baseline up to 28 days after the last dose

Population: Safety population included all participants who receive at least 1 dose of study treatment.

ArmMeasureGroupValue (NUMBER)
Bosutinib + Letrozole (Part 2)Percentage of Participants With Treatment-Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)AEs100 percentage of participants
Bosutinib + Letrozole (Part 2)Percentage of Participants With Treatment-Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs)SAEs31.3 percentage of participants
Secondary

Progression-Free Survival (PFS) Based on Investigator

Time in weeks from date of randomization to first documentation of objective tumor progression or death due to any cause. PFS: calculated as (first event date minus the date of randomization plus 1) divided by 7. Tumor progression: determined from oncologic assessment data (where data meet the criteria for PD), or from AE data (where the outcome was Death). PFS assessed by investigator was to be reported.

Time frame: Part 2 Baseline, every 8 weeks up to 2 to 6 weeks after last dose

Population: Data were not analyzed because the study was prematurely terminated due to unfavorable risk benefit ratio of the study treatment.

Secondary

Time to Reach Maximum Observed Plasma Concentration (Tmax)

Time frame: 0 hour (pre-dose) on Day 1; 2, 3, 4, 6, 8, 24 hours post-dose on Day 29

Population: Data were not analyzed because the study was prematurely terminated due to unfavorable risk benefit ratio of the study treatment.

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026