A Study to Assess Efficacy and Safety of Pertuzumab Given in Combination With Trastuzumab and Vinorelbine in Participants With Metastatic or Locally Advanced Human Epidermal Growth Factor Receptor (HER) 2-Positive Breast Cancer

Inclusion Criteria:

Histologically or cytologically confirmed and documented adenocarcinoma of the breast with metastatic or locally advanced disease not amenable to curative resection
HER2-positive as assessed by local laboratory on primary or metastatic tumor
At least one measurable lesion and/or non-measurable disease evaluable according to RECIST v1.1 criteria
Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1
Left ventricular ejection fraction (LVEF) of at least 55%
Life expectancy of at least 12 weeks

Exclusion Criteria:

Previous systemic non-hormonal anti-cancer therapy in the metastatic or locally advanced breast cancer setting
Previous approved or investigative anti-HER2 agents in any breast cancer treatment setting, except trastuzumab and/or lapatinib in the adjuvant or neoadjuvant setting
Disease progression while receiving trastuzumab and/or lapatinib in the adjuvant or neoadjuvant setting
Disease-free interval from completion of adjuvant or neoadjuvant systemic non-hormonal treatment to recurrent disease of less than 6 months
History of persistent Grade 2 or higher (National Cancer Institute Common Terminology Criteria [NCI-CTC], Version 4.0) hematological toxicity resulting from previous adjuvant or neoadjuvant therapy
Radiographic evidence of central nervous system metastases that are not well controlled with local therapy (irradiation or surgery)
Current peripheral neuropathy of NCI-CTC, version 4.0 Grade 3 or greater
History of other malignancy within the last 5 years, except for carcinoma in situ of the cervix, non-melanoma skin carcinoma, Stage 1 uterine cancer, or cancers with a similar curative outcome as those mentioned above
Serious uncontrolled concomitant disease that would contraindicate the use of any of the investigational drugs used in this study or would put the participants at high risk for treatment-related complications
Inadequate hematologic, liver, or renal function
Uncontrolled hypertension or clinically significant cardiovascular disease
Hepatitis B, hepatitis C, or human immunodeficiency virus (HIV) infection
Current chronic daily treatment with corticosteroids (>/= 10 mg/day methylprednisolone or equivalent), excluding inhaled steroids