Ahead of schedule, the Food and Drug Administration (FDA) approved Perjeta (pertuzumab) to treat patients with early-stage breast cancer prior to surgery (neoadjuvant) on Sept. 30. This comes on the heels of a unanimous vote from the Oncology Drugs Advisory Committee to recommend the drug for approval. Perjeta was approved just last year to treat patients with metastatic HER-2 positive breast cancer.
Perjeta is the first drug approved for the neodjuvant treatment of cancer and provides another treatment option for patients at high risk of a breast cancer recurrence, metastasis or of dying from the disease. Perjeta is still intended for HER-2 positive patients, but has now been extended to include those with inflammatory, locally advanced or early-stage breast cancer who are at high risk. Perjeta is to be used in combination with Herceptin (trastuzumab) and chemotherapy, and depending on the combination used, chemotherapy can be used after surgery as well. Herceptin, however, should be continued after surgery to complete a year of treatment.
Perjeta was approved under the FDA’s accelerated approval program, which provides patients access to drugs for serious conditions while further ongoing trials are conducted. The drug was approved based on a phase 2 trial in which 417 participants were randomly assigned to receive one of four treatment combinations prior to surgery (given every three weeks for four cycles of treatment): Herceptin and docetaxel; Perjeta, Herceptin and docetaxel; Perjeta and Herceptin; or Perjeta and docetaxel. Thirty-nine percent of those receiving the Perjeta, Herceptin and docetaxel combination achieved a complete pathologic response, which means there was no detectable invasive cancer in the breast or lymph nodes. Only about 21 percent of those who received Herceptin plus docetaxel achieved a complete pathologic response. Perjeta is also the first drug approved based on a pathologic complete response instead of traditional endpoints, such as survival data and progression-free survival.
A large, phase 3 trial, called APHINITY, is ongoing to confirm these results and also examine the long-term effects of Perjeta. Approximately 4,800 participants with HER-2 positive breast cancer who have received prior breast cancer surgery and are at high risk for cancer recurrence are enrolled. Results from this trial are expected in 2016. Perjeta is still being further explored for treating breast cancer as well as other HER-2 positive cancers, colorectal and gastric cancers.
When asked for a comment, Lisa Carey, medical director of the UNC Breast Center in Chapel Hill, N.C., said that it is important that the FDA is recognizing the need for more flexible and nimble approaches. “This is a good one since the neoadjuvant trial was well designed and completed,” she says. “The adjuvant trials, which will define this in terms of more clinically meaningful results, are finished collecting patients and just need to mature. So this is a good proof-of-principle for using the neoadjuvant approach as an intermediate.”