
Could a blood test help more lung cancer patients get drugs that are targeted to the genetic weaknesses of their tumors?
Yes, according to summary results of a 282-patient clinical trial being made available Wednesday. The result is a boon for Guardant Health, the San Francisco-based startup that sells the test, Guardant360, which is a “liquid biopsy” that works by detecting fragments of DNA in the bloodstream. The full study will be presented in full at the annual meeting of the American Association for Cancer Research in early April.
All of the 282 patients had been newly diagnosed with non-small cell lung cancer. Each received both a traditional biopsy — a small amount of tumor tissue removed from the lung — and the Guardant blood test to try to identify if the patient’s cancer was driven by one of seven genetic alterations (EGFR, ALK, ROS1, BRAF, RET, MET, and ERBB2) that medical guidelines say should be treated with particular targeted drugs. These changes were detected in 60 patients, or 21.3 percent, via the biopsy method and 77, or 27.3 percent, of those who received the Guardant blood test.