By Christy Santhosh and Padmanabhan Ananthan
Sept 21 (Reuters) - The US FDA's staff reviewers did not raise major concerns about the accuracy and safety of Grail's blood test designed to detect more than 50 cancers, sending the company's shares soaring 35% on Monday.
The findings on the screening test, called Galleri, will be discussed at the FDA's external advisers' meeting on Wednesday to review Grail's request for premarket approval.
The FDA has no outstanding questions for the external panel on analytical
performance, study design and the primary safety analyses of Galleri, according to the briefing documents.
But the agency asked the advisers to discuss whether the evidence supports Galleri's characterization as an "early detection" test.
"We view this as constructive for Grail," said Piper Sandler analyst David Westenberg, adding that he expects a favorable vote.
Grail's shares have plunged more than 20% since February after it said routine screening with the test failed to significantly boost early detection and reduce late-stage diagnoses in a pivotal three-year UK trial.
The company had filed for the Food and Drug Administration's approval in January based on data from a smaller US trial, first-year data from the UK trial and a bridging analysis comparing data from an earlier version of the test.
Galleri and Abbott Laboratories' multi-cancer blood test, Cancerguard, are already available on the market under the Clinical Laboratory Improvement Amendments regulations, but neither is FDA-approved.
An FDA approval ensures widespread distribution, adoption of guidelines for physicians and routine health insurance coverage.
Multi-cancer early detection tests analyze molecular signals shed by tumors into the bloodstream from a single blood draw.
Galleri is meant to complement, not replace, established screenings such as mammograms and colonoscopies, Grail has said.
The test brought in revenue of $136.8 million in the US in 2025.
(Reporting by Christy Santhosh and Padmanabhan Ananthan in Bengaluru)
