Exacerbate health disparities?
In Dr. Rebbeck’s view, the characteristics of the test are still “relatively poor for detecting very early cancers, so it will need additional tweaking before it really achieves the goal of multi-cancer EARLY detection,” he said.
Dr. Venstrom acknowledges that the test is “not perfect yet” and says the company will continue to update and improve its performance. “We have some new data coming out in September,” he said.
Clinical data are being accumulated in the United Kingdom, where the Galleri test is being investigated in a large trial run by the National Health Service (NHS). The company recently announced that the enrollment of 140,000 healthy cancer-free volunteers aged 50-77 into this trial has now been completed and claimed this the largest-ever study of a multi-cancer early detection test.
Dr. Roychowdhury said he would encourage anyone interested in the test to join a clinical trial.
Another expert approached for comment last year, when GRAIL first started marketing the test, was in agreement. This test should be viewed as one that is still under clinical investigation, commented William Grady, MD, a member of the clinical research division and public health sciences division at the Fred Hutchinson Cancer Research Center, Seattle.
“The Galleri test is still unproven in the clinical care setting and ... I am concerned that many of the results will be false-positives and will cause many unnecessary follow-up tests and imaging studies as well as anxiety in the people getting the test done,” Dr. Grady said.
Dr. Rebbeck said another issue that needs to be addressed is whether all populations will have access to and benefit from these types of blood tests to screen for cancer, given that they are expensive.
“There is a great danger – as we have seen with many other technological innovations – that the wealthy and connected benefit, but the majority of the population, and particularly those who are underserved, do not,” Dr. Rebbeck said.
“As a result, health disparities are created or exacerbated. This is something that needs to be addressed so that the future use of these tests will provide equitable benefits,” he added.
Dr. Rebbeck and Dr. Roychowdhury have reported no relevant financial relationships. Dr. Venstrom is an employee of GRAIL.
A version of this article first appeared on Medscape.com.