NEW YORK (GenomeWeb) – Myriad Genetics said it has submitted the first module of its premarket approval application for myChoice HRD CDx with the US Food and Drug Administration.
The firm is seeking approval of myChoice HRD as a test that can identify patients with ovarian, fallopian, or peritoneal cancer whose tumors are deficient in homologous recombination DNA repair, regardless of their BRCA mutation status, and may benefit from treatment with GlaxoSmithKline's niraparib (Zejula) as a fourth-line option.
"In clinical studies, the myChoice HRD test effectively identified heavily pre-treated patients with ovarian, fallopian or primary peritoneal cancer who are likely to benefit from Zejula," Nicole Lambert, president of Myriad Oncology, said in a statement.
Myriad's submission to the FDA will include data from the QUADRA study, in which the objective response rate was 28 percent and the median duration of response was 9.2 months in patients who received fourth and fifth-line treatment with niraparib, were platinum chemotherapy sensitive, and homologous recombination deficient by myChoice HRD.
The tissue-based myChoice HRD detects whether patients have somatic mutations in BRCA1 and BRCA2 genes and other "genomic scars" — through heterozygosity loss, telomeric allelic imbalance, and large-scale state transitions — that make them unable to correct DNA damage and more likely to respond to DNA-damaging drugs.
Myriad previously collaborated with drugmaker Tesaro, recently acquired by GSK, to use myChoice HRD in a study for niraparib in recurrent ovarian cancer patients. Although the study showed that ovarian cancer patients with germline BRCA mutations and who were HRD-positive lived significantly longer without their disease progressing on niraparib compared to placebo, patients in the overall population also benefitted from the drug. Myriad had said at the time that it would still submit for approval for myChoice HRD regardless of this data.
The agency ended up approving niraparib as a maintenance treatment for recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer after patients' tumors have shrunk with platinum-based chemotherapy, and approved Myriad's BRACAnalysis CDx as a complementary diagnostic to inform treatment strategies with the drug.