Grail Galleri Test Fails Primary Goal but Detects 937 Cancers in Large UK Study

Grail presented results from its largest study to date at the American Society of Clinical Oncology meeting in Chicago. The study tracked more than 140,000 older people in the UK who took the company's $950 Galleri blood test each year for three years. Insider reported that the test searches for upwards of 50 types of cancer by looking for tell-tale signs of cancer DNA in blood.

The study did not achieve its goal of meaningfully curbing late-stage cancers. Grail President and incoming CEO Joshua Ofman said the test still produced a clear benefit. "When you add Galleri to single cancer, standard-of-care screening, we found four times more cancer in the population," Ofman told Insider.

An additional 937 cancers were detected by the Galleri test. Of those cancers found by the test, 54% were in Stages 3 and 4. People who took the test had fewer Stage 4 diagnoses and more cases identified at Stage 3.

After three years, Stage 1 and 2 cancer detection improved by 16% overall. The test showed larger gains for certain cancers that lack routine screening. Grail doubled the number of Stage 1 and 2 ovarian cancer cases detected.

3% increase in Stage 1 and 2 esophagus cancer diagnoses. The test demonstrated high specificity. 5%.

Still, 864 people received a cancer signal from the test but were not diagnosed with cancer afterward. Grail founding CEO Jeff Huber addressed the false positive results. "When you get a Grail test result, and it says you have cancer, you can be highly, highly, highly confident you have cancer," Huber said.

He added that previous research showed about a third of false positive tests later became cancer diagnoses when followed over longer periods. Dr. Scott Ramsey, who directs the Institute for Cancer Outcomes Research at Fred Hutch Cancer Center and was not involved in the study, said a positive result would prompt further investigation.