New Test Identifies Prostate Cancer Patients With BRCA Mutations

Cancer liquid biopsy is a blood plasma test that is less invasive than a tissue biopsy for assessing germline or somatic BRCA mutations
men running up a rocky hill

A Colorado-based biopharmaceutical company announced that the U.S. Food and Drug Administration (FDA) approved the FoundationOne® Liquid CDx, Foundation Medicine’s comprehensive liquid biopsy test for all solid tumors with multiple companion diagnostic indications.

This FDA approval was published on August 27, 2020, and includes Rubraca ® (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.

mCRPC is an incurable disease, usually associated with poor prognosis.

According to the American Cancer Society, the 5-year survival rate for mCRPC is approximately 30 percent, and approximately 12 percent of patients with mCRPC harbor a deleterious germline and/or somatic mutation in the genes BRCA1 and BRCA2.

FoundationOne Liquid CDx expected availably is August 28, 2020, and is intended for use by healthcare professionals to help inform cancer treatment decisions in accordance with FDA-approved labeling and professional guidelines for patients with solid tumors.

“Tumors with BRCA mutations are by far the most responsive to PARP inhibitors in metastatic castration-resistant prostate cancer, and when we started the 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, in a press statement. 

“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%), comparable to (44%), 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.

“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.”

Approximately 43,000 men in the U.S. are expected to be diagnosed with mCRPC in 2020.

Clovis Oncology, Inc. is a biopharmaceutical company focused on acquiring, developing, and commercializing innovative anti-cancer agents in the U.S., Europe, and additional international markets. 

Vax-Before-Cancer publishes research-based oncology news.