Pertuzumab Granted Priority Review for Neoadjuvant HER2-Positive Breast Cancer

July 9, 2013

Last week, the FDA announced that it would grant priority review to pertuzumab (Perjeta), as a neoadjuvant treatment for women with HER2-positive early-stage breast cancer.

Last week, the FDA announced that it would grant priority review to pertuzumab (Perjeta), as a neoadjuvant treatment for women with HER2-positive early-stage breast cancer.

Pertuzumab was approved a year ago, in combination with trastuzumab and docetaxel, for the treatment of HER2-positive metastatic breast cancer.

The application is based primarily on results from two phase II studies, NeoSphere and TRYPHAENA. The safety results are taken from the long-term safety results of the phase III study CLEOPATRA, which examined the drug in metastatic patients.

NeoSphere was a multicenter open-label study in 417 treatment-naive women with HER2-positive breast cancer. The patients were randomly assigned to one of four treatment groups: trastuzumab plus docetaxel (group A), pertuzumab and trastuzumab plus docetaxel (group B), pertuzumab and trastuzumab (group C), or pertuzumab plus docetaxel (group D).

The primary endpoint of the trial was pathological complete response rate. Patients assigned to group B had a significantly improved pathological complete response rate of 45.8%, compared with 29% in group A, 24% in group D, and 16.8% in group C.

The TRYPHAENA study compared outcomes in 225 patients with HER2-positive early-stage breast cancer assigned to one of three different neoadjuvant treatment arms: pertuzumab, trastuzumab and anthracycline-based chemotherapy followed by pertuzumab, trastuzumab, and docetaxel (group A); anthracycline-based chemotherapy followed by pertuzumab, trastuzumab, and docetaxel (group B); or pertuzumab, trastuzumab, docetaxel, and carboplatin chemotherapy (group C). The primary endpoint of the study was cardiac safety.

Pathological completed response was 61.6% in group A, 57.3% in group B, and 66.2% in group C. The results also indicated that treatment of pertuzumab with trastuzumab and standard chemotherapy resulted in low rates of symptomatic left ventricular systolic dysfunction.

The priority review of the drug will result in a decision on approval by October 31.