FDA Approves Pertuzumab for HER2+ Breast Cancer

Yesterday, the FDA approved pertuzumab (Perjeta) in combination with trastuzumab and chemotherapy as an adjuvant therapy for patients with early-stage human epidermal growth factor receptor 2 positive (HER2+) breast cancer who are at high risk of experiencing recurrence, according to a press release.

The new approval was based on positive data from the APHINITY clinical trial, which included 4804 patients with early-stage HER2+ breast cancer whose primary tumors were resected.

Patients were randomized to receive treatment with pertuzumab or placebo plus adjuvant trastuzumab and chemotherapy. The primary efficacy outcome was invasive disease-free survival (IDFS), which was defined as the time from randomization to ipsilateral local or regional invasive disease recurrence, distant recurrence, contralateral invasive breast cancer, or death, according to the release. Patients were followed for a median of 45.4 months.

The researchers found that the number of IDFS events was 7.1% in the pertuzumab cohort and 8.7% in the placebo cohort, according to the FDA.

High-risk patients included those with hormone receptor negative (HR-) disease and those with node-positive disease. The investigators discovered that the number of IDFS events in patients with HR- breast cancer was 8.2% in the pertuzumab cohort and 10.6% in the placebo cohort. IDFS events among patients with node-positive disease was 9.2% in the pertuzumab group and 12.1% in the placebo cohort, according to the study.

The FDA reports that overall survival data are not available yet.

Adverse reactions included diarrhea, nausea, alopecia, fatigue, peripheral neuropathy, and vomiting. The most common serious adverse were neutropenia, febrile neutropenia, diarrhea, neutrophil count decreased, anemia, diminished white blood cell count, leukopenia, fatigue, nausea, and stomatitis, according to the release.

The FDA notes that pertuzumab is indicated as an 840-mg initial dose administered over 60 minutes, followed by 420-mg every 3 weeks administered over 30 to 60 minutes.

In 2012, pertuzumab was approved in combination with trastuzumab and docetaxel for patients with HER2+ metastatic breast cancer who have not received prior treatment for metastatic disease.

In 2013, pertuzumab was granted accelerated approval as a neoadjuvant treatment, with the new adjuvant approval meeting the required post-marketing studies. Pertuzumab is now granted regular approval as an adjuvant treatment in combination with trastuzumab and chemotherapy in patients with HER2+ locally advanced, inflammatory, or early stage breast cancer, according to the release.