(ChemotherapyAdvisor) – The U.S. Food and Drug Administration has approved pertuzumab (Perjeta) in combination with trastuzumab (Herceptin) and docetaxel chemotherapy for the treatment of people with HER2-positive metastatic breast cancer who have not received prior anti-HER2 therapy or chemotherapy for metastatic breast cancer (MBC).
Phase 3 data from the international randomized, double-blind, placebo-controlled CLEOPATRA (CLinical Evaluation Of Pertuzumab And TRAstuzumab) trial showed the combination of pertuzumab, trastuzumab, and chemotherapy resulted in a median progression-free survival of 18.5 months compared with 12.4 months for trastuzumab and chemotherapy (HR=0.62; P<0.0001).
The study also found pertuzumab, trastuzumab, and chemotherapy resulted in a 38% reduction in risk of disease worsening or death compared to those who received trastuzumab and chemotherapy plus placebo (HR=0.62; P<0.0001).
According to the prescribing information, the most common adverse reactions (>30%) with pertuzumab in combination with trastuzumab and docetaxel were diarrhea, alopecia, neutropenia, nausea, fatigue, rash, and peripheral neuropathy. “The most common Grade 3 to 4 adverse reactions (>2%) were neutropenia, febrile neutropenia, leukopenia, diarrhea, peripheral neuropathy, anemia, asthenia, and fatigue. An increased incidence of febrile neutropenia was observed for Asian patients in both treatment arms compared with patients of other races and from other geographic regions. Among Asian patients, the incidence of febrile neutropenia was higher in the pertuzumab-treated group (26%) compared with the placebo-treated group (12%),” the document states.
High levels of HER2 are found in approximately 25% of breast cancer cases. Pertuzumab and trastuzumab bind to different places on the HER2 receptor, providing what is believed to be a more comprehensive blockade of HER signaling pathways.
The American Cancer Society estimates approximately 229,000 people will be diagnosed with breast cancer in 2012; of those, 30% will develop MBC.
Pertuzumab is manufactured by Genentech, South San Francisco, CA.