On January 12, the U.S. Food and Drug Administration approved Lynparza (olaparib), the PARP inhibitor partnered by AstraZeneca and Merck, for the treatment of BRCA-mutated, HER2-negative advanced metastatic breast cancer.
The FDA’s action adds another cancer type for Lynparza; in late 2014 it was the first PARP inhibitor to be approved for use in BRCA-mutated advanced ovarian cancer, an indication that was later extended to include maintenance therapy for platinum-sensitive recurrent ovarian cancer regardless of BRCA mutation status. Moreover, this is the first approval for any PARP inhibitor in the breast cancer setting — although Pfizer’s talazoparib is not far behind. Pfizer announced that talazoparib successfully completed a Phase 3 clinical trial in BRCA-mutated breast cancer in December 2017.
Lynparza is currently also under evaluation in prostate and pancreatic cancer, as well as in immunotherapy combinations with Merck’s Keytruda (pembrolizumab) and AstraZeneca’s Imfinizi (durvalumab).
We believe the new approval should make BRCA testing as routine for breast cancer treatment decisions as HER2 and hormone receptor status are today. Myriad Genetic Laboratories’ BRACAnalysisCDx was simultaneously approved for use as a companion diagnostic to identify breast cancer patients with germline BRCA mutations who may be candidates for Lynparza. Approximately 20-25% of patients with hereditary breast cancer and 5-10% of patients with any form of breast cancer have mutations in the BRCA gene, which is normally involved in DNA damage repair.