Guardant Health, an oncology company, has secured the approval of the US Food and Drug Administration (FDA) for the company’s Guardant360 CDx liquid biopsy assay as a companion diagnostic for ORSERDU (elacestrant).

The FDA approval as a companion diagnostic for ORSERDU marks Guardant Health’s first in breast cancer and the fifth for the Guardant360 CDx test.

Guardant360 CDx as a companion diagnostic for Menarini Group’s ORSERDU is indicated for patients with ESR1 mutations in estrogen receptor (ER)-positive,  human epidermal growth factor receptor 2 (HER2)-negative advanced or metastatic breast cancer.

From a simple blood draw, the liquid biopsy assay test from Guardant Health is claimed to give comprehensive genomic results in seven days to help identify patients with ESR1 mutations who may benefit from ORSERDU targeted therapy.

Helmy Eltoukhy — Guardant Health co-CEO said: “This FDA approval is great news for breast cancer patients with ESR1 mutations, who now have, for the first time, an approved treatment for their specific type of cancer and a blood-based companion diagnostic.

“We are pleased that the Guardant360 CDx liquid biopsy is now approved so that oncologists and their patients can access comprehensive genomic profiling to see if they are eligible to receive this therapy.”

The FDA-approved ORSERDU is indicated for the treatment of postmenopausal women or adult men, with ER+, HER2-, ESR1-mutated advanced or metastatic breast cancer with disease progression following at least one line of endocrine therapy.

ORSERDU, which is a nonsteroidal selective estrogen receptor degrader, will be commercialized by Stemline Therapeutics, a fully-owned subsidiary of Italian pharmaceutical and diagnostics company Menarini Group.

Elcin Barker Ergun — Menarini Group CEO said: “We are proud to bring the very first treatment targeting ESR1 mutations which are present in up to 40% of ER+/HER2- advanced breast cancers.

“We’re also pleased with the approval of the Guardant360 CDx blood test as the companion diagnostic to help oncologists identify patients who may benefit from this innovative endocrine therapy.”

Previously, Guardant360 CDx was approved as a companion diagnostic for TAGRISSO (osimertinib), ENHERTU (fam-trastuzumab deruxtecan-nxki), RYBREVANT (amivantamab-vmjw), and LUMAKRAS (sotorasib) for the treatment of patients with non-small cell lung cancer.

  Breast Cancer, elacestrant, Elcin Barker Ergun, Endocrine therapy, Guardant Health, Guardant360 CDx, Helmy Eltoukhy, Menarini Group, Metastatic breast cancer, Oncology, ORSERDU, Stemline Therapeutics, US Food and Drug Administration, USA