Neurology > > Alzheimer’s Disease– Amyloid AD-Detect test not used on Quest’s customer platform
by Judy George, Deputy Managing Editor, MedPage Today March 12, 2024
A Quest Diagnostics Alzheimer’s blood test that individuals might buy from home without going to a physician initially is no longer being marketed straight to customers.
The test, called Quest AD-Detect, determines amyloid-beta 42 and amyloid-beta 40 in blood to offer an amyloid-beta 42/40 (AB 42/40) ratio.
Mission Diagnostics initially revealed AD-Detect as a consumer-initiated test on July 31, 2023, however the test is no longer used on the business’s customer platform.
“We stopped briefly providing our consumer-initiated AB 42/40 test at the end of 2023, in part to enhance our concentrate on our main doctor channel,” a Quest Diagnostics representative informed MedPage Today
The choice followed several interactions including Quest, the Alzheimer’s Association, and biomarker scientists.
AD-Detect has actually not been cleared or authorized by the FDA. It is still being marketed to doctors, though no peer-reviewed research study documents confirming its precision have actually been released.
Initial information supporting AD-Detect existed in an abstract at the 2022 Alzheimer’s Association International Conference, from a research study of 209 individuals. In August 2023, after MedPage Today raised concerns about the information, the abstract authors stated the level of sensitivity and uniqueness quotes were accidentally changed.
On Aug. 21, 2023, the abstract was modified to consist of a brand-new sentence that mentioned that, at the amyloid-beta 42/40 cut-point of 0.160, “the assay has a level of sensitivity of 89% and uniqueness of 71% for finding PET-positivity, which is suggestive of advertisement [Alzheimer’s disease]”
Alzheimer’s specialists on the Alzforum networking website preserved that the uniqueness numbers weren’t sufficient.
“With the kind of clients that Quest appears to be targeting with their low uniqueness test, a favorable test outcome might be false-positive more frequently than it is true-positive,” Suzanne Schindler, MD, PhD, of Washington University in St. Louis, informed MedPage Today“This might trigger unneeded client stress and anxiety and more concern memory centers that are currently extended thin.”
AD-Detect is not a diagnostic test, Quest stated. It is a laboratory-developed test (LDT) that utilizes liquid chromatography and mass spectrometry. LDTs like Quest AD-Detect are managed by the Clinical Laboratory Improvement Amendments (CLIA) program of the Centers for Medicare & & Medicaid Services, which does not deal with the medical credibility of any tests.
The FDA just recently proposed modifications to LDT oversight, revealing issue that clients who utilize them for Alzheimer’s illness, cancer, cardiovascular disease, and other conditions might start unneeded treatment or hold-up or give up appropriate treatment based upon unreliable LDT outcomes.
“These commonly utilized tests are not normally pertaining to the FDA for evaluation or otherwise adhering to FDA requirements,” FDA Commissioner Robert Califf, MD, stated when the firm’s proposition was revealed last September.
“This leaves Americans susceptible to making essential health care options based upon possibly malfunctioning or incorrect test outcomes,” Califf explained.