The Food and Drug Adminis-tration (FDA) has approved Myriad Genetics’ BRACAnalysis CDx for use as a companion diagnostic to identify HER2-negative metastatic breast cancer patients who have a germline BRCA mutation and are candidates for treatment with the poly (ADP-ribose) polymerase inhibitor Lynparza (olaparib). Lynparza is marketed by AstraZeneca and Merck and is known as MSD outside of the U.S. and Canada. BRACAnalysis CDx is the first and only FDA-approved test for use in this indication. Specifically, this test detects and classifies variants in the protein coding regions and intron/exon boundaries of the BRCA1 and BRCA2 genes using genomic DNA obtained from whole blood specimens. It uses polymerase chain reaction (PCR) and Sanger sequencing to detect single nucleotide variants and small insertions and deletions in the BRCA genes, and multiplex PCR to detect large deletions and duplications. The BRACAnalysis CDx was previously approved in 2014 to help identify patients with advanced ovarian cancer who are eligible for fourth-line treatment with Lynparza.