Myriad Files sPMA With FDA for Test to ID Best Responders to Lynparza, Avastin Combination

NEW YORK – Myriad Genetics said it has submitted a supplementary premarket approval application to the US Food and Drug Administration for myChoice CDx as a companion diagnostic for olaparib (AstraZeneca/Merck's Lynparza) in combination with bevacizumab (Genentech's Avastin).

In January, the FDA accepted AstraZeneca and Merck's supplementary new drug application for the olaparib/bevacizumab combination and granted it priority review for the maintenance treatment of advanced ovarian cancer patients who are responding to first-line platinum chemotherapy with bevacizumab.

The drugmakers submitted data from the Phase III PAOLA-1 trial, which showed that patients receiving bevacizumab added to olaparib had a 41 percent lower risk of disease progression or death compared to those just receiving bevacizumab. The median progression-free survival was 22.1 months in the combination arm versus 16.6 months in the bevacizumab arm. 

The agency is expected to issue a decision on the olaparib/bevacizumab sNDA in the second quarter of this year.

Although AstraZeneca and Merck are seeking approval for the combination in advanced platinum-sensitive advanced ovarian cancer patients without a predictive biomarker, Myriad has decided to submit its myChoice CDx for FDA review based on data from the PAOLA-1. The test assesses patients for homologous recombination deficiency, and within PAOLA-1 the benefit of olaparib/bevacizumab maintenance therapy was particularly pronounced in those who were HRD positive with BRCA mutations, with median progression-free survival of 37.2 months versus 17.7 months on bevacizumab alone; as well as those who were HRD positive but BRCA mutation negative, with median progression-free survival of 28.1 versus 16.6 months.

In January, Myriad similarly announced it had submitted an sPMA for myChoice CDx to assess newly diagnosed advanced ovarian cancer patients with HRD who are likely to respond to niraparib (GlaxoSmithKline's Zejula). In that case, Myriad made the filing for its test despite GSK seeking approval for its drug in this setting regardless of HRD status. 

It remains to be seen if the FDA will view the test as a companion diagnostic in these settings, requiring it for the safe and effective use of the olaparib/bevacizumab and niraparib, or a complementary diagnostic for guiding treatment strategy.

The test, however, is FDA approved as a companion diagnostic for niraparib in heavily pretreated ovarian cancer patients who are platinum sensitive and have HRD. Because the test has FDA approval, it has allowed Myriad to apply for and receive advanced diagnostic laboratory test status for myChoice CDx, and bill Medicare initially at the list price of $4,040. 

During an earnings call last week, during which the company announced second quarter earnings had declined 10 percent year over year, Myriad highlighted that expanding the indications for myChoice CDx was among its future revenue growth strategies.