FDA Approves FoundationOne CDx as Companion Diagnostic Test for Piqray Treatment

The U.S. Food and Drug Administration (FDA) has approved Foundation Medicine’s FoundationOne CDx as a companion diagnostic test for identifying advanced breast cancer patients with a PIK3CA mutation suitable for treatment with Piqray (alpelisib).

Piqray was approved in May, in combination with Faslodex (fulvestrant), for postmenopausal women and men with HR-positive, HER2-negative advanced breast cancer who had failed prior hormone therapy and carried a mutation in the PIK3CA gene.

It is the first and only treatment approved for the PIK3CA-mutated breast cancer population.

By examining multiple genes and select gene rearrangements, FoundationOne CDx is intended to select breast cancer patients who may benefit from Piqray.

Due to its broad genetic analysis, it also is approved as a companion diagnostic test for 18 additional targeted therapies. These include treatments for multiple solid tumors, including HER2-targeted therapies for breast cancer and PARP inhibitors for ovarian cancer.

“Foundation Medicine is proud to achieve another FDA approval for FoundationOne CDx as a companion diagnostic for Piqray for the treatment of metastatic breast cancer with a PIK3CA mutation,” Brian Alexander, MD, MPH, chief medical officer of Foundation Medicine, said in a press release. “The advancements we are seeing in the treatment of breast cancer underscore the importance of harnessing genomic insights to enable personalized medicine.”

“Taking a comprehensive and validated approach to genomic testing is critical for patients with metastatic breast cancer to help physicians determine a treatment roadmap upfront that may include FDA-approved targeted therapies like Piqray,” he added.

Approximately 40% of patients with HR /HER2- breast cancer also have a mutation in the PIK3CA gene, making it the most commonly mutated gene in this population. Individuals with PIK3CA mutations are more likely to experience higher tumor growth, be more resistant to hormone-based treatments, and have a poor overall prognosis.

Piqray, developed by Novartis, is a PIK3CA inhibitor. It is meant to help overcome resistance to hormone treatment and to inhibit the detrimental effects of PIK3CA mutations in people with HR-positive advanced breast cancers.

The therapy’s approval came after a Phase 3 trial, called SOLAR-1 (NCT02437318), showed that patients lived nearly twice as long without disease progression — 11 months vs. 5.7 months — when Piqray was added to standard treatment with Faslodex .

Since then, treatment guidelines have been updated, recommending that PIK3CA mutational status be assessed as part of the workup of HR-positive, HER2-negative advanced breast cancers.

Foundation Medicine is also presenting new data at the 2019 San Antonio Breast Cancer Symposium, being held in San Antonio, Texas, regarding the clinical usefulness of using comprehensive genomic profiling in cancer care.