A Study to Evaluate the Efficacy and Safety of Pertuzumab + Trastuzumab + Docetaxel Versus Placebo + Trastuzumab + Docetaxel in Previously Untreated Human Epidermal Growth Factor Receptor 2 (HER2)-Positive Metastatic Breast Cancer

A Phase III, Randomized, Double-blind, Placebo-controlled Clinical Trial to Evaluate the Efficacy and Safety of Pertuzumab+Herceptin+Docetaxel Versus Placebo+Herceptin+Docetaxel in Previously Untreated HER2-Positive Metastatic Breast Cancer

Status

Completed

Phases

Phase 3

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT02896855

Acronym

PUFFIN

Enrollment

243

Registered

2016-09-12

Start date

2016-09-13

Completion date

2021-01-22

Last updated

2021-12-16

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 Phase III, randomized, double-blind, placebo-controlled, multicenter clinical trial in China will evaluate the efficacy and safety of pertuzumab + trastuzumab + docetaxel compared with placebo + trastuzumab + docetaxel in participants with previously untreated HER2-positive metastatic breast cancer.

Interventions

DRUGDocetaxel

Docetaxel (75-mg/m\^2) was administered by IV infusion every 3 weeks until disease progression or unacceptable toxicity.

DRUGPertuzumab

Pertuzumab (840-mg loading dose for Cycle 1, followed by 420 mg for subsequent cycles) was administered by IV infusion every 3 weeks until disease progression or unacceptable toxicity.

DRUGPlacebo

Placebo matched to pertuzumab was administered by IV infusion every 3 weeks until disease progression or unacceptable toxicity.

DRUGTrastuzumab

Trastuzumab (8-mg/kg loading dose for Cycle 1, followed by 6 mg/kg for subsequent cycles) was administered by IV infusion every 3 weeks until disease progression or unacceptable toxicity.

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Masking

DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Inclusion criteria

* Histologically or cytologically confirmed adenocarcinoma of the breast with locally recurrent or metastatic disease that is suitable for chemotherapy * HER2-positive metastatic breast cancer (MBC) * Left ventricular ejection fraction (LVEF) greater than or equal to (\>=) 55 percent (%) at baseline (within 42 days of randomization) * Eastern Cooperative Oncology Group Performance Status of 0 or 1 * Women of childbearing potential and men should agree to use an effective form of contraception and to continue its use for the duration of study treatment and for at least 7 months after the last dose of study treatment (trastuzumab and/or pertuzumab)

Exclusion criteria

* History of anti-cancer therapy for MBC (with the exception of one prior hormonal regimen for MBC) * History of approved or investigative tyrosine kinase/HER inhibitors for breast cancer in any treatment setting, except trastuzumab used in the neoadjuvant or adjuvant setting * History of systemic breast cancer treatment in the neo-adjuvant or adjuvant setting with a disease-free interval from completion of the systemic treatment (excluding hormonal therapy) to metastatic diagnosis of less than (\<) 12 months * History of persistent Grade \>= 2 hematologic toxicity resulting from previous adjuvant therapy * Grade \>= 3 peripheral neuropathy at randomization * History of other malignancy within the last 5 years, except for carcinoma in situ of the cervix or non-melanoma skin carcinoma that has been previously treated with curative intent * Current clinical or radiographic evidence of central nervous system (CNS) metastases * History of exposure to cumulative doses of anthracyclines * Current uncontrolled hypertension or unstable angina * History of congestive heart failure (CHF) of any New York Heart Association (NYHA) classification, or serious cardiac arrhythmia requiring treatment * History of myocardial infarction within 6 months of randomization * History of LVEF decrease to \< 50% during or after prior trastuzumab neo-adjuvant or adjuvant therapy * Current dyspnea at rest due to complications of advanced malignancy, or other diseases that require continuous oxygen therapy * Inadequate organ function within 28 days prior to randomization * Current severe, uncontrolled systemic disease * Major surgical procedure or significant traumatic injury within 28 days prior to study treatment start or anticipation of the need for major surgery during the course of study treatment * Pregnant or lactating women * History of receiving any investigational treatment within 28 days of randomization * Current known infection with human immunodeficiency virus (HIV), hepatitis C virus (HCV), or active hepatitis B virus (HBV) * Receipt of intravenous (IV) antibiotics for infection within 14 days of randomization * Current chronic daily treatment with corticosteroids (excluding inhaled steroids) * Known hypersensitivity to any of the protocol-specified study treatments * Concurrent participation in an interventional or noninterventional study

Design outcomes

Primary

Measure	Time frame	Description
Progression-Free Survival, as Determined by the Investigator Using Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST v1.1)	From date of randomization until date of PFS event (Median [range] time on study for Arm A vs. Arm B at Primary analysis: 57.14 [3.3-93.3] weeks vs. 59.64 [0.9-90.4] weeks; Final analysis: 145.29 [3.3-225.3] weeks vs. 174.79 [0.9-226.1] weeks)	Progression-free survival (PFS) was defined as the time from randomization to first occurrence of progressive disease (PD), as determined by the investigator using RECIST v1.1, or death from any cause within 18 weeks after the last tumor assessment, whichever occurred first. As per RECIST v1.1, PD is defined as a 20% increase in the sum of the diameters of target lesions, an increase in size of measurable lesions by at least 5 millimeters (mm), and the appearance of new lesions. The Kaplan-Meier approach was used to estimate median PFS for each treatment arm. Data for participants who did not have a PFS event were censored at the time of the last tumor assessment (if no tumor assessments performed after baseline, at randomization plus 1 day).
Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Progression-Free Survival at 1 to 3 Years, as Determined by the Investigator Using RECIST v1.1	At 1, 2, and 3 years	Progression-free survival (PFS) was defined as the time from randomization to first occurrence of progressive disease (PD), as determined by the investigator using RECIST v1.1, or death from any cause within 18 weeks after the last tumor assessment, whichever occurred first. As per RECIST v1.1, PD is a 20% increase in the sum of the diameters of target lesions, an increase in size of measurable lesions by at least 5 mm, and the appearance of new lesions. The Kaplan-Meier approach was used to estimate the percentage of participants who were event-free for PFS at 1, 2, and 3 years. Data for participants who did not have a PFS event were censored at the time of the last tumor assessment (if no tumor assessments performed after baseline visit, at randomization plus 1 day). At final analysis, the median \[range\] time on study for Arm A vs. Arm B was 145.29 \[3.3-225.3\] weeks vs. 174.79 \[0.9-226.1\] weeks.

Secondary

Measure	Time frame	Description
Percentage of Participants With Measurable Disease at Baseline Who Achieved an Objective Response (Complete or Partial Response), as Determined by the Investigator Using RECIST v1.1	At Baseline and every 9 weeks from date of randomization until disease progression or death, whichever occurs first (Median [range] time on study for Arm A vs. Arm B at Primary analysis: 57.14 [3.3-93.3] weeks vs. 59.64 [0.9-90.4] weeks)	An objective response was defined as a complete response (CR) or partial response (PR), as determined by the investigator using RECIST v1.1. As per RECIST v1.1, CR is defined as the disappearance of all target lesions, and PR is defined as at least a 30% decrease in the sum of diameters of target lesions. Also per RECIST v1.1, stable disease (SD) is defined as neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for progressive disease (PD), taking as reference the smallest sum on study; PD is defined as a 20% increase in the sum of the diameters of target lesions, an increase in size of measurable lesions by at least 5 mm, and the appearance of new lesions. The same assessment technique must be used throughout the study for evaluating a particular lesion, and the same investigator should assess all tumor responses for each participant. Participants without a post-baseline tumor assessment were considered non-responders.
Duration of Objective Response, as Determined by the Investigator Using RECIST v1.1	From date of first occurrence of documented objective response to date of event (Median [range] time on study for Arm A vs. Arm B at Primary analysis: 57.14 [3.3-93.3] weeks vs. 59.64 [0.9-90.4] weeks)	Duration of objective response was defined as the time from the first occurrence of a documented objective response (complete response \[CR\] or partial response \[PR\]) to the time of disease progression, as determined by the investigator using RECIST v1.1, or death from any cause within 18 weeks after the last tumor assessment, whichever occurred first. As per RECIST v1.1, CR is defined as the disappearance of all target lesions, and PR is defined as at least a 30% decrease in the sum of diameters of target lesions. The Kaplan-Meier approach was used to estimate median duration of objective response. Data for participants who did not have an event were censored at the time of the last tumor assessment (if no tumor assessments were performed after baseline visit, at randomization plus 1 day).
Number of Participants With at Least One Adverse Event	From first dose of study drug until 42 days after last dose of study drug (up to 4 years, 4 months)	The number of participants per treatment arm experiencing at least one adverse event, including all non-serious and serious adverse events, is reported here. Adverse events reported prior to first crossover treatment were included in the Placebo arm, and in the Crossover arm after that date, for participants in Arm A who crossed over from placebo to pertuzumab. At final analysis, the median \[range\] time on study treatment with placebo or pertuzumab per arm was: Arm A - Placebo: 52.3 \[3-207\] weeks; Arm B - Pertuzumab: 66.1 \[3-225\] weeks; Arm A - Crossover to Pertuzumab: 18.1 \[12-24\] weeks.
Number of Participants With at Least One Grade ≥3 Adverse Event	From first dose of study drug until 42 days after last dose of study drug (up to 4 years, 4 months)	Adverse event (AE) severity was assessed according to the National Cancer Institute Common Terminology Criteria for Adverse Events, Version 4.0 (NCI-CTCAE v4.0); if the AE was not specifically listed, the following grades of severity were used: Grade 1 = mild; Grade 2 = moderate; Grade 3 = severe; Grade 4 = life-threatening or disabling; and Grade 5 = death. Severe and serious are not synonymous. Severity refers to the intensity of an AE, whereas a serious AE must meet criteria set out in the protocol; both were independently assessed for each AE. AEs reported prior to first crossover treatment were included in the Placebo arm, and in the Crossover arm after that date, for participants in Arm A who crossed over from placebo to pertuzumab. At final analysis, the median \[range\] time on study treatment with placebo or pertuzumab per arm was: Arm A - Placebo: 52.3 \[3-207\] weeks; Arm B - Pertuzumab: 66.1 \[3-225\] weeks; Arm A - Crossover to Pertuzumab: 18.1 \[12-24\] weeks.
Overall Survival	From date of randomization until the date of death from any cause (Median [range] time on study for Arm A vs. Arm B at Final analysis: 145.29 [3.3-225.3] weeks vs. 174.79 [0.9-226.1] weeks)	Overall survival (OS) was defined as the time from randomization to death from any cause. The Kaplan-Meier approach was used to estimate median OS for each treatment arm. Participants who were alive or lost to follow-up at the time of the analysis were censored at the date they were last known to be alive. Participants with no post-baseline information were censored at the time of randomization plus 1 day. The results reported here are from the final analysis. At the primary completion date, the median duration of OS had not been reached and OS data was not considered mature due to the few number of events reported.
Number of Participants With Symptomatic Left Ventricular Systolic Dysfunction (LVSD), as Determined Using Echocardiography (ECHO) or Multiple-Gated Acquisition (MUGA) Scan	From first dose of study drug until 42 days after last dose of study drug (up to 4 years, 4 months)	The number of participants with symptomatic left ventricular systolic dysfunction (LVSD) at any time during the study, as determined using echocardiography (ECHO) or multiple-gated acquisition (MUGA) scan, were summarized by treatment arm. Symptomatic LVSD was evaluated according to NCI CTCAE v4.0 (for heart failure) and the New York Heart Association (NYHA) classification. At final analysis, the median \[range\] time on study treatment with placebo or pertuzumab per arm was: Arm A - Placebo: 52.3 \[3-207\] weeks; Arm B - Pertuzumab: 66.1 \[3-225\] weeks; Arm A - Crossover to Pertuzumab: 18.1 \[12-24\] weeks.
Number of Participants With an Asymptomatic Decline in Left Ventricular Ejection Fraction (LVEF) Event, as Determined Using ECHO or MUGA Scan	From first dose of study drug until 42 days after last dose of study drug (up to 4 years, 4 months)	An asymptomatic decline in LVEF event is reported as an adverse event of ejection fraction decreased and is defined as either of the following: an absolute decrease in LVEF of ≥10 percentage points from baseline to an LVEF of \<50%; or an asymptomatic decrease in LVEF requiring treatment or leading to discontinuation of pertuzumab (or placebo) and trastuzumab. At final analysis, the median \[range\] time on study treatment with placebo or pertuzumab per arm was: Arm A - Placebo: 52.3 \[3-207\] weeks; Arm B - Pertuzumab: 66.1 \[3-225\] weeks; Arm A - Crossover to Pertuzumab: 18.1 \[12-24\] weeks.
Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Baseline, Weeks 9, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99, 108, 117, 126, 135, 144, 153, 162, 171, 180, 189, 198, 207, 216, and 225, Study Drug Discontinuation Visit (up to 4 years, 4 months), and Treatment-Free Follow-Up at 6 months, and 1 and 2 years	Left ventricular ejection fraction (LVEF) is the measurement of how much blood is being pumped out of the left ventricle of the heart with each contraction. LVEF was calculated using the modified Simpson method and must have been ≥55% at baseline as determined by the local facility before a participant could be enrolled in the study. The investigator decided which method of LVEF assessment (ECHO \[preferred\] or MUGA scan) would be used for each participant at baseline, and the same method was to be used throughout the study, to the extent possible. The LVEF abnormality status categories, as a change relative to LVEF at baseline, included: Increase or no change in LVEF; Decrease of \<10 LVEF points; Absolute LVEF value ≥50% and a decrease of ≥10 LVEF points; and Absolute LVEF value \<50% and a decrease of ≥10 LVEF points. The overall worst LVEF value was defined as the lowest post-baseline value up to the end of the study, including unscheduled assessments and the post-treatment period.
Baseline LVEF and Change From Baseline to Maximum On-Treatment Decrease in LVEF at Any Point During the Study	Baseline and every 9 weeks from date of randomization until treatment discontinuation (up to 4 years, 4 months)	The baseline left ventricular ejection fraction (LVEF) and change from baseline to the maximum on-treatment decrease in LVEF at any point during the study are reported here. LVEF is the measurement of how much blood is being pumped out of the left ventricle of the heart (the main pumping chamber) with each contraction. LVEF was calculated using the modified Simpson method and must have been ≥55% at baseline as determined by the local facility before a participant could be enrolled in the study. The investigator decided which method of LVEF assessment (ECHO \[preferred\] or MUGA scan) would be used for each participant at baseline, and the same method should have been used throughout the study, to the extent possible. At final analysis, the median \[range\] time on study for Arm A vs. Arm B was 145.29 \[3.3-225.3\] weeks vs. 174.79 \[0.9-226.1\] weeks.
Number of Participants With at Least One Adverse Event Leading to Withdrawal From Any Treatment	From first dose of study drug until 42 days after last dose of study drug (up to 4 years, 4 months)	Adverse events reported prior to first crossover treatment were included in the Placebo arm, and in the Crossover arm after that date, for participants in Arm A who crossed over from placebo to pertuzumab. At final analysis, the median \[range\] time on study treatment with placebo or pertuzumab per arm was: Arm A - Placebo: 52.3 \[3-207\] weeks; Arm B - Pertuzumab: 66.1 \[3-225\] weeks; Arm A - Crossover to Pertuzumab: 18.1 \[12-24\] weeks.
Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Overall Survival at 1 to 3 Years	At 1, 2, and 3 Years	Overall survival (OS) was defined as the time from randomization to death from any cause. The Kaplan-Meier approach was used to estimate the percentage of participants who were event-free for OS (i.e., alive) at 1, 2, and 3 years. Participants who were alive or lost to follow-up at the time of the analysis were censored at the date they were last known to be alive. Participants with no post-baseline information were censored at the time of randomization plus 1 day. At final analysis, the median \[range\] time on study for Arm A vs. Arm B was 145.29 \[3.3-225.3\] weeks vs. 174.79 \[0.9-226.1\] weeks.

Countries

China

Participant flow

Participants by arm

Arm	Count
Arm A: Placebo + Trastuzumab + Docetaxel Placebo matched to pertuzumab, trastuzumab (8-milligrams per kilogram \[mg/kg\] loading dose for Cycle 1, followed by 6 mg/kg for subsequent cycles), and docetaxel (75-milligrams per square meter \[mg/m\^2\]) were administered by intravenous (IV) infusion every 3 weeks until disease progression or unacceptable toxicity. Following the primary analysis and upon approval of protocol version 4 (07-March-2020), the treatment assignment of participants in Arm A who were still on study treatment was unblinded, allowing the investigators to present those participants with the option to cross over and receive pertuzumab (in place of placebo) in addition to trastuzumab and docetaxel.	121
Arm B: Pertuzumab + Trastuzumab + Docetaxel Pertuzumab (840-mg loading dose for Cycle 1, followed by 420 mg for subsequent cycles), trastuzumab (8-mg/kg loading dose for Cycle 1, followed by 6 mg/kg for subsequent cycles), and docetaxel (75-mg/m\^2) were administered by IV infusion every 3 weeks until disease progression or unacceptable toxicity.	122
Total	243

Withdrawals & dropouts

Period	Reason	FG000	FG001
Overall Study	Death	50	40
Overall Study	Lost to Follow-up	15	9
Overall Study	Withdrawal by Subject	7	4

Baseline characteristics

Characteristic	Arm A: Placebo + Trastuzumab + Docetaxel	Arm B: Pertuzumab + Trastuzumab + Docetaxel	Total
Age, Continuous	51.3 years STANDARD_DEVIATION 11.2	50.7 years STANDARD_DEVIATION 10.6	51.0 years STANDARD_DEVIATION 10.9
Disease Type: Visceral or Non-Visceral Disease Non-Visceral Disease	35 Participants	34 Participants	69 Participants
Disease Type: Visceral or Non-Visceral Disease Visceral Disease	86 Participants	88 Participants	174 Participants
Hormone Receptor Status Estrogen and/or Progesterone Receptor Positive	73 Participants	69 Participants	142 Participants
Hormone Receptor Status Estrogen and Progesterone Receptor Negative	48 Participants	53 Participants	101 Participants
Measurable or Non-Measurable Disease, According to RECIST v1.1 Measurable Disease	97 Participants	105 Participants	202 Participants
Measurable or Non-Measurable Disease, According to RECIST v1.1 Non-Measurable Disease	24 Participants	17 Participants	41 Participants
Race/Ethnicity, Customized Asian	121 Participants	122 Participants	243 Participants
Sex: Female, Male Female	121 Participants	122 Participants	243 Participants
Sex: Female, Male Male	0 Participants	0 Participants	0 Participants

Adverse events

Event type	EG000 affected / at risk	EG001 affected / at risk	EG002 affected / at risk
deaths Total, all-cause mortality	50 / 120	40 / 122	0 / 12
other Total, other adverse events	114 / 120	119 / 122	5 / 12
serious Total, serious adverse events	23 / 120	30 / 122	1 / 12

Outcome results

Primary

Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Progression-Free Survival at 1 to 3 Years, as Determined by the Investigator Using RECIST v1.1

Progression-free survival (PFS) was defined as the time from randomization to first occurrence of progressive disease (PD), as determined by the investigator using RECIST v1.1, or death from any cause within 18 weeks after the last tumor assessment, whichever occurred first. As per RECIST v1.1, PD is a 20% increase in the sum of the diameters of target lesions, an increase in size of measurable lesions by at least 5 mm, and the appearance of new lesions. The Kaplan-Meier approach was used to estimate the percentage of participants who were event-free for PFS at 1, 2, and 3 years. Data for participants who did not have a PFS event were censored at the time of the last tumor assessment (if no tumor assessments performed after baseline visit, at randomization plus 1 day). At final analysis, the median \[range\] time on study for Arm A vs. Arm B was 145.29 \[3.3-225.3\] weeks vs. 174.79 \[0.9-226.1\] weeks.

Time frame: At 1, 2, and 3 years

Population: ITT population: consists of all randomized participants, regardless of whether they received any study treatment. Participants are grouped according to the treatment group to which they were randomized. The number analyzed per timepoint represents the number of participants remaining at risk for a PFS event at that timepoint.

Arm	Measure	Group	Value (NUMBER)
Arm A: Placebo + Trastuzumab + Docetaxel	Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Progression-Free Survival at 1 to 3 Years, as Determined by the Investigator Using RECIST v1.1	1 Year	52.90 estimate of percentage of participants
Arm A: Placebo + Trastuzumab + Docetaxel	Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Progression-Free Survival at 1 to 3 Years, as Determined by the Investigator Using RECIST v1.1	2 Years	19.19 estimate of percentage of participants
Arm A: Placebo + Trastuzumab + Docetaxel	Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Progression-Free Survival at 1 to 3 Years, as Determined by the Investigator Using RECIST v1.1	3 Years	12.73 estimate of percentage of participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Progression-Free Survival at 1 to 3 Years, as Determined by the Investigator Using RECIST v1.1	1 Year	66.37 estimate of percentage of participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Progression-Free Survival at 1 to 3 Years, as Determined by the Investigator Using RECIST v1.1	2 Years	37.85 estimate of percentage of participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Progression-Free Survival at 1 to 3 Years, as Determined by the Investigator Using RECIST v1.1	3 Years	29.44 estimate of percentage of participants

Primary

Progression-Free Survival, as Determined by the Investigator Using Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST v1.1)

Progression-free survival (PFS) was defined as the time from randomization to first occurrence of progressive disease (PD), as determined by the investigator using RECIST v1.1, or death from any cause within 18 weeks after the last tumor assessment, whichever occurred first. As per RECIST v1.1, PD is defined as a 20% increase in the sum of the diameters of target lesions, an increase in size of measurable lesions by at least 5 millimeters (mm), and the appearance of new lesions. The Kaplan-Meier approach was used to estimate median PFS for each treatment arm. Data for participants who did not have a PFS event were censored at the time of the last tumor assessment (if no tumor assessments performed after baseline, at randomization plus 1 day).

Time frame: From date of randomization until date of PFS event (Median [range] time on study for Arm A vs. Arm B at Primary analysis: 57.14 [3.3-93.3] weeks vs. 59.64 [0.9-90.4] weeks; Final analysis: 145.29 [3.3-225.3] weeks vs. 174.79 [0.9-226.1] weeks)

Population: Intent-to-Treat (ITT) population: consists of all randomized participants, regardless of whether they received any study treatment. Participants are grouped according to the treatment group to which they were randomized.

Arm	Measure	Group	Value (MEDIAN)
Arm A: Placebo + Trastuzumab + Docetaxel	Progression-Free Survival, as Determined by the Investigator Using Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST v1.1)	Primary Analysis	12.4 months
Arm A: Placebo + Trastuzumab + Docetaxel	Progression-Free Survival, as Determined by the Investigator Using Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST v1.1)	Final Analysis	12.5 months
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Progression-Free Survival, as Determined by the Investigator Using Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST v1.1)	Primary Analysis	14.5 months
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Progression-Free Survival, as Determined by the Investigator Using Response Evaluation Criteria in Solid Tumors Version 1.1 (RECIST v1.1)	Final Analysis	16.5 months

Comparison: This was for the primary analysis. Hypothesis testing is considered exploratory in this bridging study.p-value: 0.041895% CI: [0.49, 0.99]Log Rank

Comparison: This was for the primary analysis. Hypothesis testing is considered exploratory in this bridging study.p-value: 0.055695% CI: [0.5, 1.01]Log Rank

Comparison: This was for the final analysis. Hypothesis testing is considered exploratory in this bridging study.p-value: 0.000895% CI: [0.45, 0.81]Log Rank

Comparison: This was for the final analysis. Hypothesis testing is considered exploratory in this bridging study.p-value: 0.001995% CI: [0.47, 0.85]Log Rank

Secondary

Baseline LVEF and Change From Baseline to Maximum On-Treatment Decrease in LVEF at Any Point During the Study

The baseline left ventricular ejection fraction (LVEF) and change from baseline to the maximum on-treatment decrease in LVEF at any point during the study are reported here. LVEF is the measurement of how much blood is being pumped out of the left ventricle of the heart (the main pumping chamber) with each contraction. LVEF was calculated using the modified Simpson method and must have been ≥55% at baseline as determined by the local facility before a participant could be enrolled in the study. The investigator decided which method of LVEF assessment (ECHO \[preferred\] or MUGA scan) would be used for each participant at baseline, and the same method should have been used throughout the study, to the extent possible. At final analysis, the median \[range\] time on study for Arm A vs. Arm B was 145.29 \[3.3-225.3\] weeks vs. 174.79 \[0.9-226.1\] weeks.

Time frame: Baseline and every 9 weeks from date of randomization until treatment discontinuation (up to 4 years, 4 months)

Population: Safety population, which includes participants who received at least one dose of any study drug, with participants grouped according to the treatment received. Number analyzed indicates participants with a baseline LVEF measurement and at least one post-baseline LVEF measurement, respectively.

Arm	Measure	Group	Value (MEAN)	Dispersion
Arm A: Placebo + Trastuzumab + Docetaxel	Baseline LVEF and Change From Baseline to Maximum On-Treatment Decrease in LVEF at Any Point During the Study	Baseline LVEF (value at visit)	64.23 percentage points of LVEF	Standard Deviation 4.9
Arm A: Placebo + Trastuzumab + Docetaxel	Baseline LVEF and Change From Baseline to Maximum On-Treatment Decrease in LVEF at Any Point During the Study	Change from Baseline to Max Decrease in LVEF	-4.88 percentage points of LVEF	Standard Deviation 5.41
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Baseline LVEF and Change From Baseline to Maximum On-Treatment Decrease in LVEF at Any Point During the Study	Baseline LVEF (value at visit)	65.08 percentage points of LVEF	Standard Deviation 4.43
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Baseline LVEF and Change From Baseline to Maximum On-Treatment Decrease in LVEF at Any Point During the Study	Change from Baseline to Max Decrease in LVEF	-5.48 percentage points of LVEF	Standard Deviation 5.06

95% CI: [-1.96, 0.75]

Secondary

Duration of Objective Response, as Determined by the Investigator Using RECIST v1.1

Duration of objective response was defined as the time from the first occurrence of a documented objective response (complete response \[CR\] or partial response \[PR\]) to the time of disease progression, as determined by the investigator using RECIST v1.1, or death from any cause within 18 weeks after the last tumor assessment, whichever occurred first. As per RECIST v1.1, CR is defined as the disappearance of all target lesions, and PR is defined as at least a 30% decrease in the sum of diameters of target lesions. The Kaplan-Meier approach was used to estimate median duration of objective response. Data for participants who did not have an event were censored at the time of the last tumor assessment (if no tumor assessments were performed after baseline visit, at randomization plus 1 day).

Time frame: From date of first occurrence of documented objective response to date of event (Median [range] time on study for Arm A vs. Arm B at Primary analysis: 57.14 [3.3-93.3] weeks vs. 59.64 [0.9-90.4] weeks)

Population: ITT population: consists of all randomized participants, regardless of whether they received any study treatment. Participants are grouped according to the treatment group to which they were randomized. Only participants with measurable disease at baseline who achieved an objective response during the study were included in the analysis.

Arm	Measure	Value (MEDIAN)
Arm A: Placebo + Trastuzumab + Docetaxel	Duration of Objective Response, as Determined by the Investigator Using RECIST v1.1	10.4 months
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Duration of Objective Response, as Determined by the Investigator Using RECIST v1.1	12.4 months

Comparison: Hypothesis testing is considered exploratory in this bridging study.p-value: 0.286795% CI: [0.49, 1.24]Log Rank

Secondary

Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Overall Survival at 1 to 3 Years

Overall survival (OS) was defined as the time from randomization to death from any cause. The Kaplan-Meier approach was used to estimate the percentage of participants who were event-free for OS (i.e., alive) at 1, 2, and 3 years. Participants who were alive or lost to follow-up at the time of the analysis were censored at the date they were last known to be alive. Participants with no post-baseline information were censored at the time of randomization plus 1 day. At final analysis, the median \[range\] time on study for Arm A vs. Arm B was 145.29 \[3.3-225.3\] weeks vs. 174.79 \[0.9-226.1\] weeks.

Time frame: At 1, 2, and 3 Years

Arm	Measure	Group	Value (NUMBER)
Arm A: Placebo + Trastuzumab + Docetaxel	Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Overall Survival at 1 to 3 Years	1 Year	90.64 estimate of percentage of participants
Arm A: Placebo + Trastuzumab + Docetaxel	Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Overall Survival at 1 to 3 Years	2 Years	73.85 estimate of percentage of participants
Arm A: Placebo + Trastuzumab + Docetaxel	Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Overall Survival at 1 to 3 Years	3 Years	58.41 estimate of percentage of participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Overall Survival at 1 to 3 Years	1 Year	93.44 estimate of percentage of participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Overall Survival at 1 to 3 Years	2 Years	78.87 estimate of percentage of participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Kaplan-Meier Estimate of the Percentage of Participants Event-Free for Overall Survival at 1 to 3 Years	3 Years	70.79 estimate of percentage of participants

Secondary

Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans

Left ventricular ejection fraction (LVEF) is the measurement of how much blood is being pumped out of the left ventricle of the heart with each contraction. LVEF was calculated using the modified Simpson method and must have been ≥55% at baseline as determined by the local facility before a participant could be enrolled in the study. The investigator decided which method of LVEF assessment (ECHO \[preferred\] or MUGA scan) would be used for each participant at baseline, and the same method was to be used throughout the study, to the extent possible. The LVEF abnormality status categories, as a change relative to LVEF at baseline, included: Increase or no change in LVEF; Decrease of \<10 LVEF points; Absolute LVEF value ≥50% and a decrease of ≥10 LVEF points; and Absolute LVEF value \<50% and a decrease of ≥10 LVEF points. The overall worst LVEF value was defined as the lowest post-baseline value up to the end of the study, including unscheduled assessments and the post-treatment period.

Time frame: Baseline, Weeks 9, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99, 108, 117, 126, 135, 144, 153, 162, 171, 180, 189, 198, 207, 216, and 225, Study Drug Discontinuation Visit (up to 4 years, 4 months), and Treatment-Free Follow-Up at 6 months, and 1 and 2 years

Population: Safety population, which includes participants who received at least one dose of any study drug, with participants grouped according to the treatment received. Number analyzed indicates the number of participants with a baseline LVEF measurement and a post-baseline LVEF measurement at each time point.

Arm	Measure	Group	Category	Value (COUNT_OF_PARTICIPANTS)
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Overall Worst LVEF Value (Maximum LVEF Decrease)	Decrease <10 LVEF Points	75 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 9	Increase or No Change in LVEF	57 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 9	Decrease <10 LVEF Points	51 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 9	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 9	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 18	Increase or No Change in LVEF	61 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 18	Decrease <10 LVEF Points	33 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 18	Absolute Value ≥50% & Decrease ≥10 LVEF Points	4 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 18	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 27	Increase or No Change in LVEF	54 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 27	Decrease <10 LVEF Points	35 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 27	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 27	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 36	Increase or No Change in LVEF	45 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 36	Decrease <10 LVEF Points	28 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 36	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 36	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 45	Increase or No Change in LVEF	34 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 45	Decrease <10 LVEF Points	29 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 45	Absolute Value ≥50% & Decrease ≥10 LVEF Points	5 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 45	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 54	Increase or No Change in LVEF	26 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 54	Decrease <10 LVEF Points	27 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 54	Absolute Value ≥50% & Decrease ≥10 LVEF Points	4 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 54	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 63	Increase or No Change in LVEF	21 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 63	Decrease <10 LVEF Points	17 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 63	Absolute Value ≥50% & Decrease ≥10 LVEF Points	6 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 63	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 72	Increase or No Change in LVEF	17 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 72	Decrease <10 LVEF Points	15 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 72	Absolute Value ≥50% & Decrease ≥10 LVEF Points	5 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 72	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 81	Increase or No Change in LVEF	19 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 81	Decrease <10 LVEF Points	12 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 81	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 81	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 90	Increase or No Change in LVEF	17 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 90	Decrease <10 LVEF Points	11 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 90	Absolute Value ≥50% & Decrease ≥10 LVEF Points	2 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 90	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 99	Increase or No Change in LVEF	14 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 99	Decrease <10 LVEF Points	10 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 99	Absolute Value ≥50% & Decrease ≥10 LVEF Points	2 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 99	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 108	Increase or No Change in LVEF	13 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 108	Decrease <10 LVEF Points	7 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 108	Absolute Value ≥50% & Decrease ≥10 LVEF Points	1 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 108	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 117	Increase or No Change in LVEF	14 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 117	Decrease <10 LVEF Points	3 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 117	Absolute Value ≥50% & Decrease ≥10 LVEF Points	1 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 117	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 126	Increase or No Change in LVEF	7 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 126	Decrease <10 LVEF Points	9 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 126	Absolute Value ≥50% & Decrease ≥10 LVEF Points	1 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 126	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 135	Increase or No Change in LVEF	6 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 135	Decrease <10 LVEF Points	8 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 135	Absolute Value ≥50% & Decrease ≥10 LVEF Points	1 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 135	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 144	Increase or No Change in LVEF	10 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 144	Decrease <10 LVEF Points	3 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 144	Absolute Value ≥50% & Decrease ≥10 LVEF Points	1 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 144	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 153	Increase or No Change in LVEF	7 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 153	Decrease <10 LVEF Points	7 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 153	Absolute Value ≥50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 153	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 162	Increase or No Change in LVEF	7 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 162	Decrease <10 LVEF Points	6 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 162	Absolute Value ≥50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 162	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 171	Increase or No Change in LVEF	7 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 171	Decrease <10 LVEF Points	4 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 171	Absolute Value ≥50% & Decrease ≥10 LVEF Points	1 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 171	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 180	Increase or No Change in LVEF	9 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 180	Decrease <10 LVEF Points	3 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 180	Absolute Value ≥50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 180	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 189	Increase or No Change in LVEF	5 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 189	Decrease <10 LVEF Points	3 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 189	Absolute Value ≥50% & Decrease ≥10 LVEF Points	1 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 189	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 198	Increase or No Change in LVEF	4 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 198	Decrease <10 LVEF Points	2 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 198	Absolute Value ≥50% & Decrease ≥10 LVEF Points	1 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 198	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 207	Increase or No Change in LVEF	2 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 207	Decrease <10 LVEF Points	1 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 207	Absolute Value ≥50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 207	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 216	Increase or No Change in LVEF	1 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 216	Decrease <10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 216	Absolute Value ≥50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 216	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Study Drug Discontinuation Visit	Increase or No Change in LVEF	45 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Study Drug Discontinuation Visit	Decrease <10 LVEF Points	28 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Study Drug Discontinuation Visit	Absolute Value ≥50% & Decrease ≥10 LVEF Points	8 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Study Drug Discontinuation Visit	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 6 Months	Increase or No Change in LVEF	20 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 6 Months	Decrease <10 LVEF Points	20 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 6 Months	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 6 Months	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 1 Year	Increase or No Change in LVEF	13 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 1 Year	Decrease <10 LVEF Points	10 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 1 Year	Absolute Value ≥50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 1 Year	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 2 Years	Increase or No Change in LVEF	1 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 2 Years	Decrease <10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 2 Years	Absolute Value ≥50% & Decrease ≥10 LVEF Points	2 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 2 Years	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Overall Worst LVEF Value (Maximum LVEF Decrease)	Increase or No Change in LVEF	21 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Overall Worst LVEF Value (Maximum LVEF Decrease)	Absolute Value ≥50% & Decrease ≥10 LVEF Points	16 Participants
Arm A: Placebo + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Overall Worst LVEF Value (Maximum LVEF Decrease)	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 135	Decrease <10 LVEF Points	18 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 6 Months	Absolute Value ≥50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 135	Absolute Value ≥50% & Decrease ≥10 LVEF Points	2 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 207	Decrease <10 LVEF Points	3 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 135	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 2 Years	Decrease <10 LVEF Points	1 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 9	Increase or No Change in LVEF	63 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 144	Increase or No Change in LVEF	18 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 9	Decrease <10 LVEF Points	52 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 207	Absolute Value ≥50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 9	Absolute Value ≥50% & Decrease ≥10 LVEF Points	4 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 144	Decrease <10 LVEF Points	10 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 9	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 6 Months	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 18	Increase or No Change in LVEF	62 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 144	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 18	Decrease <10 LVEF Points	45 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 207	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 18	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 144	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 18	Absolute Value <50% & Decrease ≥10 LVEF Points	1 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Overall Worst LVEF Value (Maximum LVEF Decrease)	Decrease <10 LVEF Points	75 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 27	Increase or No Change in LVEF	51 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 153	Increase or No Change in LVEF	12 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 27	Decrease <10 LVEF Points	43 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 216	Increase or No Change in LVEF	3 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 27	Absolute Value ≥50% & Decrease ≥10 LVEF Points	5 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 153	Decrease <10 LVEF Points	15 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 27	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 1 Year	Increase or No Change in LVEF	4 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 36	Increase or No Change in LVEF	46 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 153	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 36	Decrease <10 LVEF Points	43 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 216	Decrease <10 LVEF Points	1 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 36	Absolute Value ≥50% & Decrease ≥10 LVEF Points	4 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 153	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 36	Absolute Value <50% & Decrease ≥10 LVEF Points	1 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 2 Years	Absolute Value ≥50% & Decrease ≥10 LVEF Points	1 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 45	Increase or No Change in LVEF	36 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 162	Increase or No Change in LVEF	17 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 45	Decrease <10 LVEF Points	43 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 216	Absolute Value ≥50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 45	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 162	Decrease <10 LVEF Points	12 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 45	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 1 Year	Decrease <10 LVEF Points	14 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 54	Increase or No Change in LVEF	38 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 162	Absolute Value ≥50% & Decrease ≥10 LVEF Points	1 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 54	Decrease <10 LVEF Points	34 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 216	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 54	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 162	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 54	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 225	Increase or No Change in LVEF	1 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 63	Increase or No Change in LVEF	30 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 171	Increase or No Change in LVEF	10 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 63	Decrease <10 LVEF Points	33 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 225	Decrease <10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 63	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 171	Decrease <10 LVEF Points	16 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 63	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 225	Absolute Value ≥50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 72	Increase or No Change in LVEF	26 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 171	Absolute Value ≥50% & Decrease ≥10 LVEF Points	2 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 72	Decrease <10 LVEF Points	31 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 225	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 72	Absolute Value ≥50% & Decrease ≥10 LVEF Points	4 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 171	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 72	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Overall Worst LVEF Value (Maximum LVEF Decrease)	Absolute Value <50% & Decrease ≥10 LVEF Points	2 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 81	Increase or No Change in LVEF	29 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 180	Increase or No Change in LVEF	8 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 81	Decrease <10 LVEF Points	24 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Study Drug Discontinuation Visit	Increase or No Change in LVEF	45 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 81	Absolute Value ≥50% & Decrease ≥10 LVEF Points	2 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 180	Decrease <10 LVEF Points	14 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 81	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 1 Year	Absolute Value ≥50% & Decrease ≥10 LVEF Points	1 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 90	Increase or No Change in LVEF	24 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 180	Absolute Value ≥50% & Decrease ≥10 LVEF Points	1 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 90	Decrease <10 LVEF Points	20 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Study Drug Discontinuation Visit	Decrease <10 LVEF Points	39 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 90	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 180	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 90	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 2 Years	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 99	Increase or No Change in LVEF	21 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 189	Increase or No Change in LVEF	6 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 99	Decrease <10 LVEF Points	23 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Study Drug Discontinuation Visit	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 99	Absolute Value ≥50% & Decrease ≥10 LVEF Points	2 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 189	Decrease <10 LVEF Points	9 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 99	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 1 Year	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 108	Increase or No Change in LVEF	15 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 189	Absolute Value ≥50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 108	Decrease <10 LVEF Points	24 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Study Drug Discontinuation Visit	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 108	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 189	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 108	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Overall Worst LVEF Value (Maximum LVEF Decrease)	Absolute Value ≥50% & Decrease ≥10 LVEF Points	22 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 117	Increase or No Change in LVEF	18 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 198	Increase or No Change in LVEF	6 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 117	Decrease <10 LVEF Points	18 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 6 Months	Increase or No Change in LVEF	18 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 117	Absolute Value ≥50% & Decrease ≥10 LVEF Points	3 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 198	Decrease <10 LVEF Points	5 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 117	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 2 Years	Increase or No Change in LVEF	2 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 126	Increase or No Change in LVEF	20 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 198	Absolute Value ≥50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 126	Decrease <10 LVEF Points	15 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Treatment-Free Follow-Up at 6 Months	Decrease <10 LVEF Points	18 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 126	Absolute Value ≥50% & Decrease ≥10 LVEF Points	2 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 198	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 126	Absolute Value <50% & Decrease ≥10 LVEF Points	0 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Overall Worst LVEF Value (Maximum LVEF Decrease)	Increase or No Change in LVEF	20 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 135	Increase or No Change in LVEF	15 Participants
Arm B: Pertuzumab + Trastuzumab + Docetaxel	Number of Participants by the LVEF Abnormality Status Categories Over Time, as Determined by the Change From Baseline in LVEF Using ECHO or MUGA Scans	Week 207	Increase or No Change in LVEF	5 Participants

Secondary

Number of Participants With an Asymptomatic Decline in Left Ventricular Ejection Fraction (LVEF) Event, as Determined Using ECHO or MUGA Scan

An asymptomatic decline in LVEF event is reported as an adverse event of ejection fraction decreased and is defined as either of the following: an absolute decrease in LVEF of ≥10 percentage points from baseline to an LVEF of \<50%; or an asymptomatic decrease in LVEF requiring treatment or leading to discontinuation of pertuzumab (or placebo) and trastuzumab. At final analysis, the median \[range\] time on study treatment with placebo or pertuzumab per arm was: Arm A - Placebo: 52.3 \[3-207\] weeks; Arm B - Pertuzumab: 66.1 \[3-225\] weeks; Arm A - Crossover to Pertuzumab: 18.1 \[12-24\] weeks.