[Pertuzumab (Perjeta®) approval in HER2-positive metastatic breast cancers]

Fifteen to 20% of breast cancers display HER2 amplification. Many therapeutic successes have been obtained for this subtype in the last decade since trastuzumab approval for metastatic and localized diseases. Pertuzumab, a new anti-HER2 antibody, has been approved in 2013 by the European Medicine Agency. This drug can be used in combination with trastuzumab and docetaxel for the first line treatment of metastatic or locally recurrent non resecable HER2-positive breast cancers not previously treated by chemotherapy or HER2-inhibitors in the metastatic setting. This approval has been done after the CLEOPATRA trial results. This was a randomized, double-blind, multicentre, phase III trial evaluating the standard treatment (trastuzumab plus docetaxel) associated to pertuzumab or placebo. The authors have reported a statistically significant and clinically relevant benefit for the pertuzumab-based treatment. Median progression-free survival was 18.4 for the pertuzumab arm versus 12.5 months for the control group (p<0.001). They also observed benefits concerning the secondary endpoints: overall response rate and overall survival. Patients receiving pertuzumab presented more frequent diarrhea and febrile neutropenia but no increase in cardiac events. This drug has already been evaluated in the neoadjuvant setting with a FDA approval recently obtained. Its use in the adjuvant setting is under evaluation.