The article is online here; open access PDF. The company also issued a press release here.
To quote briefly:
A retrospective analysis was conducted on a series of 6,948 consecutive lung cancer patients tested with Guardant360. Of those, 543 could be compared to tissue genotyping results performed by other providers.
The results showed that for treatment-relevant alterations in EGFR, ALK, ROS1, RET, BRAF, MET, and KRAS, the positive concordance of Guardant360 to tissue genotyping was 92-100 percent.
Furthermore, upon following up on cases that were Guardant360-positive for an ALK fusion but negative in tissue, all patients responded to treatment with a standard-of-care ALK inhibitor.The Guardant360 test is under review at FDA, as is the FoundationAct liquid biopsy test.