It's in the Blood

People are fascinated by blood. Well, it would seem so, given our fondness for vampires, gory movies, and true crime stories. I’m not so keen on any of those, but I was struck by several recent developments about how blood tests can help diagnose medical problems faster, more definitively, and less invasively.

C'mon, it's not that bad. Credit: Bing Image Creator

Because, really, shouldn’t that be what our healthcare system always should strive for?

Take concussions. If you are a football fan, you’re very familiar with the problem that it seems very subjective about whether a player has suffered a concussion. They’re not the only ones. Millions of people suffer concussions each year – the vast majority of whom are not athletes – and more than half never get it evaluated.

In April Abbott received FDA approval for a rapid blood test, producing results in 15 minutes. It can be done at a patient’s beside, and not require a lab. "Clinicians have needed an objective way to assess patients with concussions," said Beth McQuiston, M.D., medical director in Abbott's diagnostics business. "When you look at all the other diseases, or other organs in the body, they all have blood tests to help assess what's happening. Now, we have a whole blood test that can help assess the brain right at the patient's bedside – expanding access to more health providers and therefore patients."

Expect to see the Abbott's i-STAT TBI cartridge and portable i-STAT^® Alinity^® instrument in emergency rooms, not to mention on NFL sidelines.

Credit: Abbott

Or Alzheimer’s disease. Many realize that it has historically been very difficult to diagnose, often not definitively until after death. Now a new study suggests a blood test can accurately diagnose it 90% of the time, which is much higher than even neurologists can do. The test is more accurate the later the stage of Alzheimer’s a person has.

Specifically, it measures “the ratio of plasma phosphorylated tau 217 (p-tau217) relative to non–p-tau217 (expressed as percentage of p-tau217) combined with the amyloid-β 42 and amyloid-β 40 plasma ratio (the amyloid probability score 2 [APS2]).” Got that?

“We’d love to have a blood test that can be used in a primary care physician’s office, functioning like a cholesterol test but for Alzheimer’s,” Dr. Maria Carrillo, chief science officer of the Alzheimer’s Association, told CNN. “The p-tau217 blood test is turning out to be the most specific for Alzheimer’s and the one with the most validity. It seems to be the front-runner.”

It’s not quite ready for use in your doctor’s office, though. “Right now, we don’t have guidelines for the use of these tests,” Dr. Eliezer Masliah, director of the division of neuroscience at the National Institute on Aging, warned NPR. Dr. Suzanne Schindler, an associate professor of neurology at Washington University School of Medicine in St. Louis, added: “Blood tests have developed incredibly fast for Alzheimer disease and I think [doctors] aren’t used to that rate of change.”

“The field is moving at a pace I never imagined 10 years ago,” Dr. Heather Whitson, a professor of medicine at Duke University, marveled to NPR.

We’re increasingly seeing FDA approved drug treatments for Alzheimer’s, so it’d be nice if we had FDA approved blood tests to more accurately use them.  

Last but not least, there’s colorectal cancer (CRC). The FDA recently approved Guardant Health’s Shield™ blood test for colorectal cancer screening, and is the first such blood test approved by the FDA as a primary screening option. A Guardant study found that it identified 87% of cancers that were at an early and curable stage, although it does less well at finding precancerous growths. The test is aimed at adults 45 and older who are at average risk.

Credit: Guardant Health

It’s not so much that it is better than colonoscopies – it’s not -- as it is that it should be easier to convince people to use. Despite the fact that CRC kills over 50,000 Americans annually, more than a third of older Americans are not getting screened. Even worse, more than three-fourths of those who die from CRC are not up-to-date with their screening.

“The persistent gap in colorectal cancer screening rates shows that the existing screening options do not appeal to millions of people,” said Daniel Chung, MD, gastroenterologist at Massachusetts General Hospital and Professor of Medicine at Harvard Medical School. “The FDA's approval of the Shield blood test marks a tremendous leap forward, offering a compelling new solution to close this gap.”

Dr. Sapna Syngal, director of strategic planning for prevention and early cancer detection at the Dana-Farber Cancer Center in Boston agrees, telling NBC News: “If this test increases the number of people getting screened, it’s going to have a huge impact.” 

The test is on the market now, and Guardant expects approval for coverage by Medicare and commercial insurance.

Most of us are used to getting routine blood tests for things like blood counts or cholesterol levels, so it’s exciting that blood tests are started to be used for other important health issues.

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Blood tests are all well and good, but they’re not (yet) the kind of test you’d routinely expect to use at home on your own. ARPA-H has even bigger aspirations. It just announced the Platform Optimizing SynBio for Early Intervention and Detection in Oncology (POSEIDON) program, the goal of which is “to develop first-in-class, at-home, synthetic Multi-Cancer-Early Detection (MCED) tests for the most sensitive and specific stage I detection of 30+ solid tumors* using only breath and/or urine samples.”

No blood draw or lab tech needed, just breath or urine samples done yourself at home. That’s something to shoot for.

“Access to a low-cost cancer screening test that does not need a lab test is so critical to preventing late-stage diagnoses, increasing survival rates, and reducing high treatment costs,” said ARPA-H Director Renee Wegrzyn, Ph.D. “With POSEIDON, we could put the power of cancer screening into homes in the U.S. and around the world.” 

“But what if any adult could, at their discretion, take an at-home test that could detect Stage I cancer? POSEIDON aims to create a future in which any adult can take a simple, over-the-counter test to screen for and detect 30+ cancers at Stage I, when they are still localized, to drastically improve the chances of curative treatment and survival,” said Ross Uhrich, DMD, MBA, ARPA-H POSEIDON’s Program Manager.

“But what if…” indeed.  ARPA-H is thinking big -- as it should. And as should we all.