The FDA expanded the approved use of olaparib tablets to include the treatment of patients with certain types of breast cancer that have metastasized and whose tumors have a germline BRCA-mutation, making it the first PARP inhibitor approved to treat breast cancer, and it is the first time any drug has been approved to treat certain patients with metastatic breast cancer who have a BRCA gene mutation. Patients are selected for treatment with olaparib based on an FDA-approved genetic test, BRACAnalysis CDx.
"This class of drugs has been used to treat advanced, BRCA-mutated ovarian cancer and has now shown efficacy in treating certain types of BRCA-mutated breast cancer," said Richard Pazdur, MD, Director of the FDA's Oncology Center of Excellence and Acting Director of the Office of Hematology and Oncology Products in the FDA's Center for Drug Evaluation and Research. "This approval demonstrates the current paradigm of developing drugs that target the underlying genetic causes of a cancer, often across cancer types."
The NCI estimates approximately 252,710 women will be diagnosed with breast cancer this year, and 40,610 will die of the disease. Approximately 20-25 percent of patients with hereditary breast cancers and 5-10 percent of patients with any type of breast cancer have a BRCA mutation.
Olaparib was first approved by the FDA in 2014 to treat certain patients with ovarian cancer and is now indicated for the treatment of patients with germline BRCA-mutated, HER2-negative metastatic breast cancer who have been previously treated with chemotherapy. Patients with HR-positive breast cancer should have been treated with a prior endocrine therapy or be considered inappropriate for endocrine treatment.
The FDA also expanded the approval of the BRACAnalysis CDx to include the detection of BRCA mutations in blood samples from patients with breast cancer.
The safety and efficacy of olaparib for the treatment of breast cancer was based on a randomized clinical trial of 302 patients with HER2-negative metastatic breast cancer with a germline BRCA mutation. The trial measured progression-free survival. The median progression-free survival for patients taking olaparib was 7 months compared to 4.2 months for patients taking chemotherapy only.
Common side effects of olaparib include anemia, neutropenia, leukopenia, nausea, fatigue, vomiting, nasopharyngitis, respiratory tract infection, influenza, diarrhea, arthralgia/myalgia, dysgeusia, headache, dyspepsia, decreased appetite, constipation, and stomatitis. Severe side effects include development of myelodysplastic syndrome/acute myeloid leukemia and pneumonitis.
This application was granted Priority Review, under which the FDA's goal is to take action on an application within 6 months where the agency determines that the drug, if approved, would significantly improve the safety or effectiveness of treating, diagnosing, or preventing a serious condition.