GRAIL Inc. (NASDAQ: GRAL) presented results from its PATHFINDER 2 study at the American Society of Clinical Oncology Annual Meeting on May 31. The study involved 35,878 participants aged 50 and older and evaluated the Galleri multi-cancer early detection test alongside standard cancer screenings.

The study found that adding the Galleri test to recommended screenings for breast, colorectal, cervical and lung cancers increased cancer detection by 6.5 times. When added to screenings that include prostate cancer, the test increased detection by nearly three times.

Of the 440 cancers diagnosed in the study, 60% were screen-detected. The Galleri test identified 173 cancer cases among 287 participants who received positive test results, yielding a positive predictive value of 60.3%. The test demonstrated 99.6% specificity, resulting in a false positive rate of less than 0.4%.

According to the study results, 71% of new cancers detected by the Galleri test were found in stages I-III, with more than half in stages I or II. The test correctly identified the cancer signal origin 91.3% of the time, leading to diagnostic resolution within a median of 48 days.

The study reported five adverse events during diagnostic evaluation, occurring only in participants with confirmed cancer diagnoses. One serious adverse event related to diagnostic work-up was identified after data collection ended.

PATHFINDER 2 represents the largest interventional study of a multi-cancer early detection test in North America. The prospective study evaluated participants with no clinical suspicion of cancer at enrollment across sites in the United States and Canada.