GRAIL has announced promising initial results from its ongoing PATHFINDER 2 study, designed to assess the Galleri multi-cancer early detection (MCED) test among adults over 50 years old in the US.
This investigation evaluates Galleri when combined with standard cancer screening in a cohort of 35,878 individuals without suspected cancer. Initial data from 25,578 participants highlights enhanced cancer detection capabilities and consistent safety outcomes.
The PATHFINDER 2 study builds on previous findings where the inclusion of the Galleri test in routine cancer screenings more than doubled the detected cancer cases. In this phase, the test demonstrated improved performance with higher positive predictive values compared to earlier studies.
The accuracy of identifying the origin of detected cancer signals and test specificity remained aligned with prior results. No significant safety issues emerged during this phase, said the company.
GRAIL President Josh Ofman said: “We are delighted to see very encouraging performance of the Galleri MCED test as a cancer screening tool in broad intended use populations of asymptomatic adults over 50 years of age in both the PATHFINDER 2 study and the NHS-Galleri trial’s prevalent screening round.”
GRAIL plans to submit these findings for review by the US Food and Drug Administration (FDA) as part of its premarket approval application for Galleri. This submission will include comparative analyses between different versions of the Galleri test used in various trials, including the NHS-Galleri trial.
The company aims to complete this modular submission by the first half of 2026 under an FDA breakthrough device designation.
Further insights from the PATHFINDER 2 study are expected to be shared at a forthcoming international oncology conference. This extensive, interventional study assesses both the safety and efficacy of Galleri, particularly in relation to diagnostic evaluations for participants flagged by a cancer signal detected result.
It also examines how well Galleri performs across several criteria such as positive predictive value, negative predictive value, sensitivity, specificity, and cancer signal origin prediction accuracy.
Secondary goals include investigating the use of traditional cancer screening methods following an MCED test and evaluating participant feedback regarding anxiety and satisfaction levels post-test.
GRAIL’s Galleri test shows enhanced cancer detection in study. (Credit: GRAIL)
