Priority Review Granted to Neoadjuvant Breast Cancer Regimen

Hal Barron, MD

The FDA has granted priority review to a regimen of pertuzumab (Perjeta), trastuzumab (Herceptin), and docetaxel for the treatment of patients with HER2-positive early-stage breast cancer. If approved, this regimen would be the first neoadjuvant regimen approved for the treatment of cancer.

According to an announcement made by pertuzumab’s manufacturer, Genentech, a member of the Roche group, the FDA will make a decision regarding this supplemental Biologics License Application (sBLA) on or before October 31, 2013.

“The impact of treatment in breast cancer is greatest in the early stage, before the cancer has spread to other parts of the body,” said Hal Barron, MD, chief medical officer and head of Global Product Development at Genentech, in a statement. “We look forward to working with the FDA to bring this potential option to people with HER2-positive early stage breast cancer as soon as possible.”

Neoadjuvant treatments are given after a diagnosis but prior to surgery in order to reduce the tumor size and either make the tumor easier to remove via surgery or offer an opportunity to conserve more tissue. According to Genentech, there are currently no FDA-approved neoadjuvant regimens for the treatment of cancer.

The priority review was based on the results of two phase II clinical trials, the NEOSPHERE trial and the TRYPHAENA trial.

In the NEOSPHERE trial, 417 patients with newly diagnosed HER2-positive, locally advanced, inflammatory, or early-stage breast cancer were randomly assigned to one of four study arms, which included combinations of pertuzumab, trastuzumab, and docetaxel. In the group that received pertuzumab (loading dose 840 mg, followed by 420 mg every 3 weeks), trastuzumab (8 mg/kg loading dose, followed by 6 mg/kg every 3 weeks), and docetaxel (75 mg/m², escalating, if tolerated, to 100 mg/m² every 3 weeks), the pathological complete response rate (pCR) was 45.8% (95% CI, 36.1-55.7), which was significantly higher than the pCR in the groups receiving combinations that did not include all three agents.¹

The TRYPHAENA study enrolled 225 patients with HER2-positive, locally advanced, inflammatory or early-stage breast cancer and studied cardiac safety. The highest pCR was observed in patients who received pertuzumab, trastuzumab, docetaxel, and carboplatin chemotherapy, with a pCR of 66.2%. The adverse events reported in the trial were consistent with what was observed which each of the three agents, and low rates of symptomatic left ventricular systolic dysfunction were reported.²

In 2012, pertuzumab, in combination with trastuzumab and docetaxel, was approved for the treatment of patients with HER2-positive metastatic breast cancer who have not received prior treatment for metastatic breast cancer with an anti-HER2 therapy or chemotherapy.

References

1. Gianni L, Pienkowski T, Im YH, et al. Efficacy and safety of neoadjuvant pertuzumab and trastuzumab in women with locally advanced, inflammatory, or early HER2-positive breast cancer (NeoSphere): a randomised, mutlticentre, open-label, phase 2 trial. Lancet Oncol. 2012 Jan; 13(1):25-32.
2. Schneeweiss A, Chia S, Hickish T, et al. Pertuzumab plus trastuzumab in combination with standard neoadjuvant anthracycline-containing and anthracycline-free chemotherapy regimens in patients with HER2-positive early breast cancer: a randomized phase II cardiac safety study (TRYPHAENA) Ann Oncol. Published online ahead of print May 22, 2013. doi:10.1093/annonc/mdt182.