A blood test designed to detect signals from multiple types of cancer has moved closer to a possible U.S. regulatory decision.
Grail’s Galleri test received a preliminary endorsement from an advisory panel to the U.S. Food and Drug Administration, marking an important stage in the company’s effort to obtain full approval.
The test is designed to look for biological signals associated with cancer in a person’s blood. Grail says the test can identify signals associated with more than 50 types of cancer and can help predict where a cancer may have originated.
The technology uses biomarkers and artificial intelligence to analyze blood samples.
The potential attraction of such a test is straightforward: a single blood sample could potentially provide information about several different cancers at the same time.
Early detection is important in cancer care because some cancers can be easier to treat when discovered before they spread.
However, the test has also generated significant discussion among medical researchers and regulators.
One of the biggest questions is whether detecting more cancers actually leads to better outcomes for patients. Finding a possible cancer signal is only the first step. Patients may need additional scans, biopsies and other tests to determine whether cancer is truly present.
False-positive results can create anxiety and lead to additional medical procedures. False-negative results can also be problematic if a cancer is present but the test fails to detect it.
Previous studies of multi-cancer detection tests have produced mixed findings, and researchers continue to investigate how effectively these technologies detect cancers at the earliest stages.
The FDA advisory panel’s recommendation is not the same as final approval. The FDA considers advice from its external experts but is not legally required to follow the panel’s recommendation.
If the test receives approval, questions about access and cost are likely to become increasingly important.
Galleri is currently available as a laboratory-developed test in the United States, but it has not had full FDA approval. Insurance coverage has therefore remained limited.
Broad insurance coverage could significantly affect how widely the test is used. Medicare coverage could also influence adoption among older Americans, although coverage decisions involve separate processes.
Supporters of multi-cancer blood tests argue that the technology could eventually complement existing screening methods and potentially identify cancers for which routine screening is currently limited.
Critics and researchers, meanwhile, have emphasized the need for evidence showing that these tests reduce deaths or improve important patient outcomes, rather than simply detecting more abnormalities.
The development of Galleri therefore represents a major moment for the broader field of cancer screening, but it does not mean that blood tests can currently replace established screening methods.
Experts continue to stress that people should follow recommended screening programs appropriate to their age and individual circumstances.
The FDA’s eventual decision will provide another important step in determining how multi-cancer blood tests could fit into modern healthcare.
