With new data in hand from an ongoing study exploring biomarkers for lung cancer, Genentech and Roche say that genomic blood tests could soon replace invasive tissue biopsies when assigning patients to targeted treatments.
Presented at the 2019 congress of the European Society for Medical Oncology, data from the Blood-First Assay Screening Trial, or BFAST, showed that a blood-based diagnostic was able to identify specific genetic mutations that help drive progression within the tumor, gathered from DNA fragments found floating in the bloodstream.
“One of the biggest recent changes in treatment of [non-small cell lung cancer, or NSCLC] has been our ability to identify targetable genetic mutations that drive progression of the disease, but it is a major challenge to get a suitable tumor sample for analysis,” study author Shirish Gadgeel, a professor at the University of Michigan Rogel Cancer Center, said in a statement.
The phase 2/3 trial screened over 2,000 patients with advanced, previously untreated NSCLC, using two next-generation sequencing blood tests.
That includes a comprehensive blood test from Roche's Foundation Medicine arm, FoundationOne Liquid, which detects four main classes of genomic alterations, microsatellite instability status and other genetic mutations that can help guide treatment decisions. The study also tested a companion diagnostic being developed by Foundation that uses tumor mutational burden as a cancer biomarker.
“We showed that liquid biopsy could be used to detect a complex type of driver mutation, called ALK, in patients with NSCLC,” Gadgeel added. “These then responded at least as well to targeted therapy as in previous studies using conventional biopsy techniques.”
About 5% of study participants had circulating tumor DNA showing ALK gene rearrangements, according to the companies, which is similar to proportions seen in traditional biopsy samples. Following assignment and first-line treatment with the ALK inhibitor Alecensa (alectinib), more than 75% of patients showed no signs of disease progression after one year.
“Obtaining tumor tissue for biomarker testing can be a challenge in many people with cancer and, as a result, some may not receive optimal treatment for their disease,” said Sandra Horning, chief medical officer and head of global product development for Roche and Genentech.
“BFAST is the first trial to show that by using a blood-based next-generation diagnostic, it is possible to identify the ALK mutation in people with non-small cell lung cancer using a blood draw alone, which means that more people could potentially benefit from Alecensa,” said Horning, who recently announced that she plans to retire at the end of the year.
Editor's note: This story has been updated with additional information from Roche, Genentech and Foundation Medicine.