The US Food and Drug Administration UU (FDA) has approved Lynparza (olaparib) for a difficult way to treat metastatic breast cancer.
HER2 negative breast cancer patients mutated by BRCA who have been previously treated with chemotherapy are now approved to be treated with Lynparza.
FDA approval is based on data showing that Lynparza – developed by AstraZeneca working with Merck (known as MSD outside of the US and Canada) – extended the time patients lived without their cancer progresses , compared to standard chemotherapy care.
"This additional approval for Lynparza represents an important advance for women with HER2-negative metastatic breast cancer with a BRCA germline mutation, which is a difficult cancer to treat," Roy Baynes, senior vice president and director of Global Clinical Development , and medical director of Merck, said in a press release.
Lynparza was initially approved by the FDA for the treatment of advanced ovarian cancer mutated by BRCA in December 2014. In August 2017, the regulatory agency extended its approval to include maintenance treatment for recurrent ovarian cancer, tubal of Fallopian or primary peritoneal cancer.
Lynparza is a PARP inhibitor, which acts to block DNA repair processes. The PARP enzyme is particularly important for DNA repair in people with BRCA mutations and its blocking prevents the survival of tumors.
"This new approval for Lynparza makes it the first and only approved PARP inhibitor in metastatic breast cancer, and the only PARP inhibitor approved beyond ovarian cancer," said Dave Fredrickson, executive vice president, chief of the Oncology business unit in AstraZeneca.
"This is significant for patients with breast cancer, such as the identification of BRCA status, in addition to hormone receptors and HER2 status becomes a potentially critical step in the treatment of their disease," he said.
The eligibility of breast cancer patients for treatment will be evaluated by a complementary diagnosis, a specific test for a treatment, developed by Myriad Genetics.
The approval is based on data from the Phase 3 OlympiAD trial (NCT02000622), which compared Lynparza with the chemotherapies Xeloda (capecitabine), Navelb ine (vinorelbine) and Halaven (eribulin).
The patients included in the trial were triple negative, which means that, in addition to the lack of HER2, their cancer did not produce estrogen receptors (ER) or progesterone receptors (PR). – or were positive for the hormone receptor (HR).
All patients were previously treated with chemotherapy. Patients with positive HR had received at least one course of hormonal treatment or were not eligible for such treatment.
The data showed that among the 205 patients treated with Lynparza, the therapy reduced the risk of disease progression or death by 42 percent compared with chemotherapy. Lynparza also triggered a response in more patients than chemotherapy: 52 percent responded to treatment, compared to only 23 percent in the chemotherapy group.
Among those who responded, 7.8 percent had a complete eradication of their cancer. However, such complete remission was observed in only 1.5 percent of patients treated with chemotherapy.
When the FDA began reviewing the Lynparza data, the researchers published their findings from Phase 3 trials in New England Journal of Medicine .
"Patients diagnosed with BRCA-related metastatic breast cancer are usually younger than other breast cancer patients and their disease is often much more aggressive and difficult to treat," said Susan M. Domchek, executive director of the BRCA. Basser Center for BRCA at the Abramson Cancer Center of the University of Pennsylvania.
"Although there is currently no cure for metastatic breast cancer, today's approval offers a new and specific option that can help delay the progression of the disease in these patients," he added. Domchek, who is a national leader in the trials of OlympiAD.