Labcorp launches liquid biopsy to detect cancer-related biomarkers

A new blood test from Labcorp could potentially help cancer patients begin the most efficient treatments as early as possible.

The Plasma Focus liquid biopsy requires only a standard blood draw to run. It looks through the sample for bits of cell-free DNA (cfDNA) that are released by tumor cells into the bloodstream and that may offer insights into the cancer treatments that’ll work most effectively for a specific patient.

Labcorp announced the launch of the new test on Wednesday; doctors will now be able to order the liquid biopsy kit for their patients directly from the company.

Plasma Focus represents the first new test to come out of Labcorp’s acquisition of Personal Genome Diagnostics. The buyout closed in February 2022 and saw Labcorp offer up $450 million in upfront cash and another $125 million in potential milestone payments to pick up the cancer genomics test maker.

The newly launched test analyzes the cfDNA in a blood sample to build a genomic profile of a patient’s tumor. It looks specifically for mutations in 33 genes—comprising biomarkers that indicate variations in non-small cell lung, colorectal, breast, esophageal, gastroesophageal junction and gastric cancers and melanoma.

The test is designed to analyze the genomic makeup of both advanced and metastatic solid tumors. It’s meant to serve as a complement to existing tissue-based genomic tests for cancer biomarkers, according to its maker, and may offer a better approach in cases where obtaining a tissue sample of a tumor via biopsy would be difficult.

Labcorp returns the Plasma Focus results within seven to 10 days, providing doctors with a report detailing all genetic variants detected and any drugs that have shown promise in treating those mutations, including treatments that are already FDA approved and those currently in clinical trials.

An analysis of Plasma Focus published earlier this year in the Journal of Molecular Diagnostics showed that the test’s positive results agreed with those of other genomic profiling tests between 89% and 100% of the time, varying based on different types of biomarkers—with the lowest positive agreement in their detection of insertions and deletions, and the highest for translocations and microsatellite instability. The study’s authors concluded that the liquid biopsy “is a highly accurate, sensitive and specific approach for cell-free DNA genomic profiling to supplement tissue testing and inform treatment decisions.”

In addition to that accuracy, the test may also offer an accelerated timeline for doctors deciding between various treatment paths for their patients.

“The development and launch of Labcorp Plasma Focus marks a pivotal moment in the use of technology to enable therapy selection for patients far earlier than previously available, allowing oncologists to better manage the care of their patients,” Brian Caveney, M.D., Labcorp’s chief medical and scientific officer, said in the announcement.