Clinical Utility of Early Vs. Late Blood Biomarker Testing for Alzheimer's Disease

The goal of this study is to evaluate whether use of the PrecivityAD2 blood biomarker assay with early result disclosure along with discretionary Precivity-ApoE proteotype testing will shorten the time to Alzheimer's Disease or non-Alzheimer's diagnosis as compared to delayed result disclosure.

Participants will be randomized into the early PrecivityAD2 blood biomarker test \& disclosure group (Cohort A) or to the later PrecivityAD2 blood biomarker test \& disclosure group (Cohort B) where blood samples will be collected and tested using the PrecivityAD2 test at Visit 1 (day 0) and Visit 2 (day 90). Participants will attend study visits for one year after their enrollment. An optional sub-study will be offered to collect information through questionnaires at each visit regarding participant's and their care-giver's experiences through the AD diagnostic journey.

Healthcare providers engaged in memory care and Alzheimer's disease (AD) management have shown significant interest in the performance of plasma tests. A collaboration with Veteran's Affairs (VA) and other closed healthcare systems represents an opportunity to examine the clinical validity and utility of blood biomarkers (BBM). The ADELAIDE study is a prospective, randomized, clinical utility, economic impact and real-world study. The BBM test under study is the PrecivityAD2 blood test that uses high-resolution liquid chromatography mass spectrometry to measure plasma Aβ42/40 and p-tau217/np-tau217 ratios. This study will assess and quantify the impact of BBM testing to overall time-to-diagnosis and time to prescription of an appropriate Alzheimer's Disease (AD) or non-AD therapy. Additionally, this study will assess the impact of BBM testing to procedure utilization and overall costs of healthcare and will assess the diagnostic confidence of clinicians that order the test.

Eligibility Criteria:
Inclusion Criteria:

1. Minimum age: 50 years.
2. Patients presenting with symptoms of mild cognitive impairment (MCI) or other cognitive impairments in which the enrolling clinician clinically suspects Alzheimer's pathology as the primary cause of symptomatic presentation
3. Patients presenting with mixed brain pathologies including MCI/ cognitive impairments in which the investigator clinically suspects Alzheimer's pathology as the primary or contributing cause of symptomatic presentation
4. Patients are able to attend study visits and standard care visits over the period of 1 year from the date of enrollment
5. Patients are able to undergo routine phlebotomy and provide up to six (6) 10 ml tube(s) of blood for study related tests plus any additional blood necessary for standard laboratory testing at each study timepoint
6. Patients are able to undergo standard care diagnostic procedures to include MRI (or CT), amyloid PET and/or CSF biomarker testing for AD diagnosis if prescribed by investigator
7. Patients are able to provide informed consent. Or, if in the opinion of the clinician, the patient is unable to adequately understand the nature of the trial and protocol requirements, a family member or appropriate representative of the patient is present to consent, with additional assent by the patient.

Exclusion Criteria

1. Patients younger than 50 years of age
2. Patients being evaluated for cognitive impairment known to be predominantly the result of a disease or condition other than AD
3. Patients previously diagnosed with AD, unless the ADELAIDE investigator has a strong clinical suspicion suggestive of an incorrect initial diagnosis upon referral
4. Patients with no cognitive impairment or clinical symptoms of AD
5. Patients desiring genetic testing for Alzheimer's disease markers without current cognitive impairment or other relevant clinical symptoms
6. Patients who are not able or not willing to undergo standard care diagnostic procedures to include MRI (or CT), amyloid PET and/or CSF biomarker testing for AD diagnosis as prescribed by investigator
7. Patients who are not able to understand the nature of the study nor the study requirements and not represented by a family member or other appropriate representative who is able to consent on behalf of the patient
8. Patients who are not able to commit to attending the required study and/or standard care visits
9. Patients who are not able to undergo routine phlebotomy or provide blood samples in the quantity required by the study protocol