A Multicenter, Open-Label, Single-Arm Study of Pertuzumab in Combination With Trastuzumab and a Taxane in First Line Treatment of Patients With HER2-Positive Advanced (Metastatic or Locally Recurrent) Breast Cancer

This multicenter, open-label, single-arm, Phase IIIb study will evaluate the safety and
tolerability of pertuzumab in combination with trastuzumab (Herceptin) and a taxane
(docetaxel, paclitaxel or nab-paclitaxel) in first-line treatment in participants with
metastatic or locally recurrent HER2-positive breast cancer. Participants will receive
pertuzumab intravenously (IV) and trastuzumab (Herceptin) IV plus a taxane in cycles of 3
weeks each until predefined study end, unacceptable toxicity, withdrawal of consent, disease
progression, or death, whichever occurs first.