Foundation Medicine's latest companion diagnostic nod pairs its blood test with Pfizer's Braftovi combo

In the decade since Foundation Medicine first launched its FoundationOne genomic profiling test to look for specific biomarkers in tumor tissue samples, it has racked up dozens of FDA approvals allowing the test to serve as a companion diagnostic for a broad spectrum of cancer drugs.

And the liquid biopsy version of the FoundationOne test isn’t far behind. FoundationOne Liquid CDx, which was unveiled in 2018, requires only a standard blood draw to perform its tumor analysis—and has now reached double-digits in its own list of companion diagnostic approvals.

The test’s 10th approval allows it to be used to pair patients with a combination of Pfizer’s encorafenib, marketed under the name Braftovi, and the cancer drug cetuximab, sold as Erbitux by Eli Lilly in the U.S., Foundation announced Friday.

With the new approval, doctors will be able to identify which of their patients with previously chemo-treated metastatic colorectal cancer have a BRAF V600E alteration and therefore may respond well to the drug duo. FoundationOne Liquid is the first comprehensive genomic profiling test cleared by the regulator for that purpose, according to its maker.

The Braftovi-Erbitux combo was cleared by the FDA in early 2020 when it became the first drug regimen specifically for that patient group, which makes up around 8% of all people with metastatic colon cancer who have previously been given few effective treatment options.

The Beacon clinical trial that led to the duo’s approval showed that they could extend patients’ survival to about 8.4 months, compared to 5.4 months for those treated only with chemotherapy. Additionally, about 20% of treated patients responded to the combination, versus only 2% of those in the chemo group.

As Mia Levy, M.D., Ph.D., Foundation’s chief medical officer, noted in the company’s announcement, making FoundationOne Liquid available as a companion diagnostic to spot the patients who could benefit from the dual-drug therapy “provides oncologists with an important, noninvasive genomic testing option for metastatic patients with this difficult-to-treat condition.”

Both the tissue- and blood-sample versions of the FoundationOne tests analyze more than 300 cancer-related genes to pinpoint biomarkers that may make an individual particularly receptive to certain treatments.

To date, the liquid biopsy version has racked up companion diagnostic approvals across prostate, ovarian, breast and non-small cell lung cancers, in addition to the latest colorectal cancer nod. The original FoundationOne test, meanwhile, boasts more than two dozen approvals across all of those indications plus melanoma and bile duct cancer, and also has the FDA’s blessing to help identify patients with certain mutations spanning all solid tumors.

Even more indications could be on the way: Earlier this week, Foundation announced that it has inked a new agreement with Merck KGaA to tailor both FoundationOne tests to be companion diagnostics for several of Merck’s therapies, including some already on the market and others still in the pipeline.