Grail Blood Test Found Seven Times More Cancers Than Standard Tests, Data Show

Grail’s Pathfinder 2 study is the largest yet for a multi-cancer blood screen. (Courtesy Grail)

Key Points

• Grail’s Galleri test, in the Pathfinder 2 study of 23,000 adults, detected seven times more cancers than standard screens.
• More than half of the cancers found by the Galleri blood test were early-stage, with many in places such as the pancreas that lack existing screening methods.
• The study found that 62% of the time the test said it found cancer, follow up investigations proved it correct.

Shares of Grail have quintupled this year to nearly $90, as investors waited for news about the Pathfinder 2 study of its cancer-detecting blood test. Management hinted this summer the numbers were substantially better than in early studies.

They are.

Grail shared the results during a meeting of the European Society for Medical Oncology in Berlin on Saturday. The company said that among 23,000 adults over 50 years old, its Galleri test found seven times the number of cancers than were detected by standard screens, such as a mammogram or colonoscopy.

More than half of the cancers found by the blood test were at a stage early enough to possibly cure, the researchers reported. Most of those early cancers were also in places such as the liver, pancreas, or ovary, which don’t even have an available screening test.

“It’s unheard of,” said Grail President Josh Ofman of the blood test detections. “Nobody’s ever shown the ability to do that before.”

The Pathfinder 2 study is the largest yet for a multi-cancer blood screen. These kinds of tests look for bits of altered DNA that cancer cells shed into the bloodstream. Grail pioneered the technology, and rivals including Exact Sciences and Guardant Health are hustling to catch up. The companies hope routine use by hundreds of millions of people could yield more than $25 billion in annual sales.

For doctors and patients, the most significant finding from the Grail study might be that 62% of the time the blood test said it found a cancer, it was proved correct by follow-up investigations, said Nima Nabavizadeh, a radiation oncologist at Portland’s Oregon Health & Science University. Nabavizadeh’s team recruited about 6,000 of the subjects in the newly reported study.

That predictive performance is substantially better than the 43% rate of an earlier 6,600-person Grail study. It is an order of magnitude better than a mammogram, which is correct less than 10% of the time that it suggests a possible cancer, according to many studies.

By reporting fewer false positives, Nabavizadeh said the blood test could avoid a lot of the “work-up anxiety” patients now suffer during follow-up investigations of a mammogram finding,

He and the other investigators believe the Pathfinder 2 results support use of Galleri as a regular cancer screen in the general population after the age of 50. That is the approval Grail will seek when it submits the results to the U.S. Food and Drug Administration next year, along with data from a large study under way in Britain. The agency can take until early 2027 to decide.

FDA approval seems likely, based on the Pathfinder 2 results. That doesn’t mean commercial success is in the bag, however.

There is little insurance coverage for the $950 test. Since Grail launched Galleri in 2021 under an exemption for lab-developed tests, annualized sales have only reached $145 million on about 170,000 tests, with net losses of about $300 million.

Medicare doesn’t normally cover cancer screening, so it can’t cover Galleri without the kind of congressional authorization that allowed coverage for mammograms and colonoscopies. Ofman noted that a bill has been drafted and enjoys wide support. He said Medicare Advantage plans have told Grail they would consider covering Galleri after it gets FDA approval.

The rise in Grail’s shares shows investors are excited. But they’ll need staying power to find out if profits will eventually justify the stock’s run.

Write to Bill Alpert at william.alpert@barrons.com