Impact of Multi-Cancer Early Detection Test on Late-Stage Cancer Diagnosis

Abstract

Background NHS-Galleri, a randomized controlled trial, evaluates the clinical utility of a blood-based multi-cancer early detection (MCED) test added to usual care among individuals aged 50-77 years in England. Methods Peripheral blood was collected at up to 3 annual visits. Following baseline blood collection, participants were randomized 1:1 to intervention (blood tested) or control (blood stored) arms. Participants and study personnel were initially blinded. Reductions of stage III/IV (primary endpoint) and IV (key secondary) cancers of 12 prespecified types in intervention vs control were measured ~3 years after the last participant’s randomization. Results Overall, 71,122 and 71,128 participants were randomized to intervention and control arm, respectively. The primary endpoint was not met (incidence rate ratio [IRR; intervention vs control]:1.03 [0.92-1.14], p=0.63). For secondary endpoints, the IRR for stage IV cancer after 3 screening rounds was 0.86 (0.74-1.00). <1% of participants experienced related adverse events, none were serious. Conclusions In NHS-Galleri, we did not observe a reduction in stage III/IV cancers across 12 prespecified cancers after 3 screening rounds when MCED testing was added to standard-of-care. Further follow-up is planned to assess how findings for stage III/IV cancers and the difference in stage IV cancers evolve over time. (Funded by GRAIL, Inc.; ClinicalTrials.gov #NCT05611632)