A Study of Pertuzumab With High-Dose Trastuzumab for the Treatment of Human Epidermal Growth Factor Receptor 2 (HER2)-Positive Metastatic Breast Cancer (MBC) With Central Nervous System (CNS) Progression Post-Radiotherapy

An Open-Label, Single-Arm, Phase II Study of Pertuzumab With High-Dose Trastuzumab for the Treatment of Central Nervous System Progression Post-Radiotherapy in Patients With HER2-Positive Metastatic Breast Cancer (PATRICIA)

This study will examine the safety and efficacy of pertuzumab in combination with high-dose trastuzumab in adult participants with HER2-positive MBC with CNS metastases and disease progression in the brain following radiotherapy.

Inclusion Criteria:

• Pathologically confirmed HER2-positive MBC
• Progression of or new brain metastases after completion of whole-brain radiotherapy or stereotactic radiosurgery
• Completion of whole-brain radiotherapy or stereotactic radiosurgery more than 60 days prior to enrollment
• Stable systemic disease
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
• LVEF at least 50%
• Adequate hematologic, renal, and hepatic function
• Life expectancy more than 12 weeks

Exclusion Criteria:

• Progression of systemic disease at Screening
• Leptomeningeal disease
• History of intolerance or hypersensitivity to study drug
• Use of certain investigational therapies within 21 days prior to enrollment
• Current anthracycline use
• Unwillingness to discontinue ado-trastuzumab emtansine or lapatinib use
• Active infection
• Pregnant or lactating women
• Significant history or risk of cardiac disease
• Symptomatic intrinsic lung disease or lung involvement
• History of other malignancy within the last 5 years