Benzinga | Aug 27, 2020 05:52AM EDT

Clovis Oncology Announced FDA Approved FoundationOne Liquid CDx to Serve as Rubraca Companion Diagnostic to Identify Eligible Patients with BRCA1/2-Mutant, Metastatic Castration-Resistant Prostate Cancer

Clovis Oncology, Inc. (NASDAQ:CLVS) announced that the U.S. Food and Drug Administration (FDA) approved the FoundationOne(r) Liquid CDx, Foundation Medicine's comprehensive liquid biopsy test for all solid tumors with multiple companion diagnostic indications, including for Rubraca (r) (rucaparib) tablets, recently approved for the treatment of adult patients with a deleterious BRCA mutation (germline and/or somatic)-associated metastatic castration-resistant prostate cancer (mCRPC) who have been treated with androgen receptor-directed therapy and a taxane-based chemotherapy.i,ii FoundationOne Liquid CDx is intended for use by health care professionals to help inform cancer treatment decisions in accordance with FDA-approved labeling and professional guidelines for patients with solid tumors.

FoundationOne Liquid CDx is intended to be used as a companion diagnostic to identify patients who may benefit from treatment with specific FDA-approved targeted therapies, including Rubraca, the first PARP inhibitor approved for the treatment of BRCA1/2-mutant mCRPC.

"Tumors with BRCA mutations are by far the most responsive to PARP inhibitors in metastatic castration-resistant prostate cancer, and when we started development of Rubraca for mCRPC, we knew it was important to develop a plasma-based companion diagnostic for physician and patient ease of use," said Patrick J. Mahaffy, President and CEO of Clovis Oncology. "What we could not have foreseen was how important a plasma-based test would be in this COVID-19 environment, in which even important procedures, such as tissue-based biopsies, can be difficult to schedule for patients. We are pleased that the FDA has approved a plasma-based companion diagnostic to identify mCRPC patients who may benefit from treatment with Rubraca."

The objective response rate in BRCA positive patients as determined by FoundationOne Liquid CDx was 46% (95% CI, 31-63), comparable to 44% (95% CI, 31-57) as determined by clinical trial assays for patients enrolled in TRITON2, highlighting the utility and consistency of using a liquid biopsy test for patient selection.i,iii

"Now that we have drugs that specifically benefit patients with BRCA mutations, the ability to identify who has these mutations is paramount," said Professor Celestia S. Higano, MD FACP, University of Washington School of Medicine. "In contrast to tissue biopsy, a liquid biopsy is a blood-plasma test that is less invasive than a tissue biopsy for assessing germline or somatic BRCA mutations. The FDA's approval of liquid biopsy tests represents a significant advancement for clinicians and patients to make timely decisions about treatment options."

Foundation Medicine expects the FoundationOne Liquid CDx to be commercially available on Friday, August 28, 2020.