The new P-tau 217 test is almost here

[Brian4]

By the way, does anyone know where one can get p-tau217 / non-p-tau217 ratio tested? That might be more important than raw p-tau217 levels, per, for example, this new paper:

https://jamanetwork.com/journals/jama/f ... ultclick=1

Thanks,
Brian

[Brian4]

"... might be more important". Emphasis on "might". According to a separate, well-conducted study, p-tau217 is all we need:

https://medicine.wustl.edu/news/accurac ... se-varies/

One biomarker, used in four of the tests, proved exceptionally accurate at identifying signs of Alzheimer’s disease: a form of tau known as phosphorylated tau 217 (p-tau217).

“Some people thought that we might need to measure multiple biomarkers to get at the different features of Alzheimer’s disease,” said Kellen Petersen, PhD, an instructor in neurology at the School of Medicine. Petersen co-led data analysis for the study and will give the oral presentation at the international Alzheimer’s conference. “That’s not what we found. P-tau217 alone can do it all. It accurately predicted levels of amyloid and tau in the brain, brain volumes and cognitive symptoms. It was more accurate than any other biomarker, or even any combination of biomarkers, across the board.”

[squirrel320]

By the way, does anyone know where one can get p-tau217 / non-p-tau217 ratio tested? That might be more important than raw p-tau217 levels, per, for example, this new paper:

https://jamanetwork.com/journals/jama/f ... ultclick=1

Thanks,
Brian

Very cool Brian - I believe this is the PrecivityAD2 test, that is also referenced as one of the top two performers in the next article that you posted on the "head to head" comparison. The online information for healthcare providers on how to get tests ordered is below:

https://precivityad.com/precivityad2-hcp

Still haven't found the actual reference ranges.... a mystery.
Sheri

[SoccerMom]

Hello! Chiming in and looking for advice...I asked my PCP to order the Labcorp P-tau 217 test for me last week, and he did. (I am 49 and E3/E4. Dad died of Lewy Body Dementia at 67 and Mom (4/4) has advanced Alzheimers at 73.) My result was .06 pg/mL. (Normal range is 0-.18 per labcorp).

I was hoping to see a result of 0.00, and with such a new test it's hard to find much good info online about what is really normal. Does .06 mean I'm heading for Alzheimer's in the next couple decades? Or is it truly normal?

Hoping someone has some insight for me!

[NF52]

Hello! Chiming in and looking for advice...I asked my PCP to order the Labcorp P-tau 217 test for me last week, and he did. (I am 49 and E3/E4. Dad died of Lewy Body Dementia at 67 and Mom (4/4) has advanced Alzheimers at 73.) My result was .06 pg/mL. (Normal range is 0-.18 per labcorp).

I was hoping to see a result of 0.00, and with such a new test it's hard to find much good info online about what is really normal. Does .06 mean I'm heading for Alzheimer's in the next couple decades? Or is it truly normal?

Hoping someone has some insight for me!

Hi SoccerMom!
I just came back from a week at the Alzheimer's Association's 2024 conference and blood-base biomarkers got a lot of coverage, including peer-reviewed research studies presented at the conference and simultaneously in journals and covered by science reporters, including the ones below.

I haven't heard or read them all, but did get the clear sense that very low levels of tau are not associated with the risk of MCI or dementia within 5 years for people who are a decade older than you. Here are two charts that may help:

Associations between baseline plasma biomarkers dichotomized at median and longitudinal Aß-PET.png

.

Image 8-2-24 at 11.39 AM.jpeg

The small second figure shows that people with "median" p-tau 217 had a score of roughly 0.70--more than 10x your score of 0.06! And anyone below 0.70 had the most flat line of risk for 5 years: to the ages of 63 on average. That means at age 63 they were not yet considered to have high levels of biomarkers.

The most positive presentation I heard was also the last, from Dr. Reisa Sperling, who said that she now envisions a "primary prevention" trial with low doses of anti-amyloid and/or anti-tau drugs for those with amyloid beta scores in the 12-19 range within the next few years, and has real hopes for either an AD vaccine that would be administered either once or yearly like a flu shot, or yearly shots or infusions of a preventative dose of drugs to keep both the immune system happy and the risk of biomarkers low--within the next 10 years.

That is well within where you, with Apoe 3/4, would be eligible for real benefit.

Nancy


MedPage Today: Alzheimer's Biomarkers Show Tantalizing Hint at Utility for Tracking Prevention

Plasma Phosphorylated Tau 217 and Aβ42/40 to Predict Early Brain Aβ Accumulation in People Without Cognitive Impairment

Being Patient: AAIC: Optimism for Alzheimer’s Blood Tests

JAMA Network: Blood Biomarkers to Detect Alzheimer Disease in Primary Care and Secondary Care

JAMA Network:Changes in Alzheimer Disease Blood Biomarkers and Associations With Incident All-Cause Dementia

Are Blood Tests for Alzheimer Disease Ready for Prime Time?

[SoccerMom]

Thank you so much! That is reassuring!

[Brian4]

Nancy, thanks for taking the time to update us on the conference! (I almost went -- would have been fun to meet!)

Quick question. The two figures indicate it's "%p-tau217" that's being measured. I believe that might be percentage phosphorylated to non-phosphorylated tau217. But I haven't read the papers yet.

Thanks,
Brian

[squirrel320]

Hello! Chiming in and looking for advice...I asked my PCP to order the Labcorp P-tau 217 test for me last week, and he did. (I am 49 and E3/E4. Dad died of Lewy Body Dementia at 67 and Mom (4/4) has advanced Alzheimers at 73.) My result was .06 pg/mL. (Normal range is 0-.18 per labcorp).

I was hoping to see a result of 0.00, and with such a new test it's hard to find much good info online about what is really normal. Does .06 mean I'm heading for Alzheimer's in the next couple decades? Or is it truly normal?

Hoping someone has some insight for me!

Hi SoccerMom!
I just came back from a week at the Alzheimer's Association's 2024 conference and blood-base biomarkers got a lot of coverage, including peer-reviewed research studies presented at the conference and simultaneously in journals and covered by science reporters, including the ones below.

...
The most positive presentation I heard was also the last, from Dr. Reisa Sperling, who said that she now envisions a "primary prevention" trial with low doses of anti-amyloid and/or anti-tau drugs for those with amyloid beta scores in the 12-19 range within the next few years, and has real hopes for either an AD vaccine that would be administered either once or yearly like a flu shot, or yearly shots or infusions of a preventative dose of drugs to keep both the immune system happy and the risk of biomarkers low--within the next 10 years.

That is well within where you, with Apoe 3/4, would be eligible for real benefit.

Nancy

Nancy, amazing that you took the time to be at the conference. I have such gratitude for everything you do for advancing a cure, your impeccable attitude and how you are always willing to dig in and share.

I had the chance to attend Reisa Sperling's session virtually and it was truly amazing! Here is to hoping for a speedy start to Ahead 2.....

One paper that I was interested in...but I I don’t know if it garnered much attention / degree of peer review etc. was:

The Bayesian approach for real-world implementation of plasma p-tau217 in tertiary care memory clinics in Thailand
https://alz-journals.onlinelibrary.wile ... 14138?af=R

The online calculator is most certainly something and is very interesting. Age, cognitive concern and plasma p-Tau 217 or 181 giving a probability of Alz! I just cannot though figure out how it is calibrated for p-Tau 217......with Alzpath giving an elevated result at 0.34 ng/L and Labcorp at 0.18 ng/L - I must be doing something wrong in converting units when I use it.

This is the link to the calculator if anyone is interested:

https://trceid.org/diagAD/

[NF52]

Nancy, thanks for taking the time to update us on the conference! (I almost went -- would have been fun to meet!)

Quick question. The two figures indicate it's "%p-tau217" that's being measured. I believe that might be percentage phosphorylated to non-phosphorylated tau217. But I haven't read the papers yet.

Thanks,
Brian

Good catch! The key to the chart includes this:

%p-tau217, ratio of phosphorylated tau 217 (p-tau217) to nonphosphorylated tau.

. I agree that it would have been fun. Would have required some luck and/or coordination also, since 8000 people were in attendance! I walked 26 miles in 6 days!

[Brian4]

8000 people! Wow! I will try to attend next year.

SoccerMom, did you get the ratio measured, or just p-tau217? Either way, the result is fairly low! Lots of time to intervene!

Brian