Grail Reports Strong Performance for Galleri Blood Test Ahead of FDA Submission

GRAIL Inc presented results from its PATHFINDER 2 study at the European Society for Medical Oncology Congress 2025, showing the Galleri multi-cancer early detection blood test detected more than 7 times as many cancers when added to standard recommended screenings.

“Cancer is the second leading cause of death worldwide as most deadly cancers are found too late. Adding Galleri to recommended screening for breast, cervical, colorectal, and lung cancers in PATHFINDER 2 yielded a more than seven-fold increase in the cancer detection rate, and more than half of the Galleri detected new cancers were found in early stages, when cancers are more treatable and potentially even curable. Galleri’s ability to accurately predict where in the body the cancer signal comes from also helps to guide a more efficient diagnostic workup,” Josh Ofman, MD, MSHS, President at GRAIL, said in a press release.

The prospective study enrolled 35 878 participants aged 50 years and older across the US and Canada with no clinical suspicion of cancer. Results were reported from 25 578 participants with at least 12 months of follow-up as of December 31, 2024.

Study Findings. The Galleri test detected a cancer signal in 216 participants (0.93% detection rate). Of those with positive results, 133 participants received cancer diagnoses (0.57% cancer detection rate), yielding a positive predictive value of 61.6%.

The test showed 40.4% episode sensitivity for all cancers and 73.7% sensitivity for the 12 cancers responsible for two-thirds of cancer deaths in the United States. Specificity was 99.6%, with a false positive rate of 0.4%.

When added to US Preventive Services Task Force grade A and B recommended screenings for breast, cervical, colorectal, and lung cancers, the test increased cancer detection more than sevenfold. When added to USPSTF A, B, and C recommendations (which include prostate cancer), Galleri detected approximately 3 times as many cancers.

Of the cancers detected by Galleri, 53.5% were stage I or II, and 69.3% were stages I through III. Approximately 75% of Galleri-detected cancers do not have standard screening options.

“These results are extremely compelling as approximately three-quarters of the Galleri-detected cancers do not have recommended screening tests today. Galleri is the only MCED test available that has been validated in an interventional trial in the screening population and could transform how we deliver cancer screening at a population level," Ofman added in the press release.

Diagnostic Workup. The test correctly identified cancer signal origin 92% of the time. Diagnostic resolution took a median of 46 days. Only 0.6% of all participants (159 of 25 114) underwent invasive procedures during diagnostic workup. Invasive procedures were twice as common in participants with cancer compared with those without cancer.

No serious study-related adverse events were reported during diagnostic workup in the safety analyzable cohort of 25 114 participants.

Regulatory Plans. GRAIL will submit data from PATHFINDER 2 and the prevalent screening round of the NHS-Galleri trial to the US Food and Drug Administration as part of the premarket approval application for Galleri, which has Breakthrough Device Designation. The company expects to complete the modular PMA submission in the first half of 2026.

Source: GRAIL PATHFINDER 2 Results Show Galleri® Multi-Cancer Early Detection Blood Test Increased Cancer Detection More Than Seven-Fold When Added to USPSTF A and B Recommended Screenings. News release. Grail. October 17, 2025. Accessed October 20, 2025. https://grail.com/press-releases/grail-pathfinder-2-results-show-galleri-multi-cancer-early-detection-blood-test-increased-cancer-detection-more-than-seven-fold-when-added-to-uspstf-a-and-b-recommended-screenings/