BRACAnalysis CDx Approved in US as Companion Diagnostic Test for First-line Lynparza Treatment

BRACAnalysis CDx Approved in US as Companion Diagnostic Test for First-line Lynparza Treatment

Myriad Genetics‘ BRACAnalysis CDx has been approved by the U.S. Food and Drug Administration as a companion diagnostic test to identify women with ovarian cancer eligible for first-line maintenance treatment with Lynparza (olaparib).

Lynparza was recently approved for patients who had a partial or complete response to first-line platinum-based chemotherapy and have inherited mutations in their BRCA genes. BRACAnalysis CDx is meant to identify these mutations and guide patient management.

This is the fifth approval of BRACAnalysis CDx as a companion diagnostic test for Lynparza, including to identify ovarian cancer patients eligible for second-line and fourth-line treatment with Lynparza and for some breast cancer indications.

“We congratulate AstraZeneca and Merck on obtaining FDA approval of Lynparza for patients with BRCA [mutated] advanced ovarian cancer, and we are excited to expand the use of BRACAnalysis CDx as the companion diagnostic test in this population,” Lloyd Sanders, president of Myriad Oncology, said in a press release. “We estimate there are more than 20,000 patients newly diagnosed with ovarian cancer in the United States every year who qualify for a BRACAnalysis CDx test.”

Lynparza, an oral medicine developed by AstraZeneca, is an inhibitor of PARP enzymes — particularly PARP1 — which are key factors for repairing DNA damage. Cancer cells accumulate errors at a faster pace than healthy cells, and stopping them from repairing these errors eventually causes them to die.

Because Lynparza targets DNA-repairing proteins, the treatment is most effective in tumors that lack other DNA-repairing proteins, such as those with mutations in the BRCA1 and BRCA2 genes.

As a result, researchers need accurate tests that identify which patients have these mutations. BRACAnalysis CDx was designed to read a patient’s DNA and find mutations that influence the activity of these proteins, making patients more susceptible to treatment. The test combines two genetic approaches, which allows the detection of both small and large inherited mutations.

The FDA approvals were based on data from the Phase 3 SOLO-1 trial (NCT01844986), where BRACAnalysis CDx was used to identify patients with inherited BRCA mutations.

In the trial, Lynparza was given as maintenance of partial or complete responses to first-line platinum-based chemotherapy to patients with advanced ovarian cancer. The treatment was significantly better than a placebo, reducing the risk of death or disease progression by 70%.

“In the SOLO1 trial, Myriad’s BRACAnalysis CDx test identified patients with advanced ovarian cancer who may benefit from Lynparza,” said Johnathan Lancaster, MD, PhD, gynecologic-oncologist and chief medical officer of Myriad Genetics. “The FDA’s approval underscores the need for all patients with ovarian cancer to know their BRACAnalysis CDx results at the time of diagnosis so they can fully understand their treatment options.”

According to Myriad, a major limitation of BRACAnalysis CDx is that it is unable to identify cancers with acquired BRCA mutations, which are estimated to make up 30% of all BRCA-mutated cancers. Thus, a negative result in BRACAnalysis CDx does not rule out the possibility of an acquired mutation in the BRCA genes.