FDA panel backs first multi-cancer blood test approval

Clinical takeaway: A favorable panel vote is advisory, and an approval decision is expected in the coming months. If approved, Galleri would layer onto routine screening, aimed at cancers with no dedicated test. 

FDA advisers took up Grail's Galleri test on Sept. 23 with three questions in front of them: whether the blood test is safe, whether it works, and whether patients stand to gain more than they lose. By day's end the panel had answered yes to all three, though not with one voice. 

Galleri works from a blood draw, reading methylation patterns that mark DNA as cancer-derived and, when it detects a signal, predicting the tissue it came from to direct the workup that follows. FDA designated it a Breakthrough Device in 2018, and Grail filed for premarket approval in January. No multi-cancer early detection test has ever held FDA authorization. 

The closest call came on effectiveness, where the panel voted six to four that the evidence supports Galleri's ability to detect cancers early in adults 50 and older. On the question of whether the test's benefits outweigh its risks, the vote ran seven to two with one abstention in favor. Safety drew no dissent: all 10 voting members backed it. 

In the two pivotal trials, Galleri detected 35% of cancers diagnosed within a year of testing in one and 31.6% in the other, with one to three false positives per 1,000 people screened. A positive result meant a cancer diagnosis within a year for 77% of those flagged in one trial and 66.2% in the other. Detection concentrated where screening has nothing to offer: sensitivity reached 47.3% and 37.3% for cancers with no recommended screening test, against 22.9% and 27.5% for cancers that have one. 

Sensitivity ran lowest where early detection matters most: 21.4% and 13.6% for stage I cancers across the two studies, against 63.2% and 60% at stage IV. FDA put that gradient to the panel directly, asking whether the data support the label's claim of early detection at all. 

The randomized NHS-Galleri trial also missed its own primary endpoint: screening produced no reduction in combined stage III and IV cancer diagnoses in aggregate, though Grail reported declines emerging after the first screening round. 

The evidence comes from two trials of an earlier version of the test: PATHFINDER 2, which enrolled 35,878 adults aged 50 or older across North America, and NHS-Galleri, which randomized 142,250 adults aged 50 to 77 within England's National Health Service. The performance figures the panel weighed came from retesting stored plasma samples with the current Galleri assay. 

The decision now sits with FDA, which is not bound by its committees and is expected to rule within months. The agency's questions to the panel sketch what an approval might carry: labeling that spells out performance by cancer type and stage, and possible post-approval studies to keep measuring benefit and risk. Galleri meanwhile stays on the market as a prescription-only laboratory-developed test. 

"Today's vote reinforces the strength of Galleri's clinical evidence," said Josh Ofman, MD, MSHS, CEO of Grail. "We believe the panel's recommendations reaffirm a high evidence bar that Grail has set for a multi-cancer early detection test." 

Source: Grail, Inc. (2026 Sep 23) press release. FDA Advisory Committee Votes In Favor of Approval of GRAIL's Galleri Multi-Cancer Early Detection Test