Hot on the heels of positive results for Eli Lilly’s Alzheimer’s disease (AD) drug donanemab, a new blood-based test could soon be hitting the AD clinical space.
The Alzheimer’s Drug Discovery Foundation (ADDF) has seen the clinical promise in ALZpath’s blood-based assay, which is currently restricted to research use only (RUO), investing $1.9m as part of its diagnostics accelerator.
According to ALZpath, a barrier in the widespread uptake of drugs such as Eli Lilly’s donanemab and the recently US Food and Drug Administration (FDA) approved Lecanemab from Biogen and Eisai, is the early diagnosis of disease onset in Alzheimer’s patients. Eli Lilly downplayed the necessity for tau testing when announcing its landmark results, but donanemab seemed to work better in patients with earlier disease progression.
California, US-based ALZpath has developed a test that non-invasively measures phosphorylated tau 217 (pTau217) in the blood. The phosphorylated tau protein is an important biomarker for AD, with pTau217 recognised as having the most utility. According to the company, its ALZpath pTau217 immunoassay is the only commercially available test that can do this.
Currently, the assay is available for RUO, but ALZpath says the investment from ADDF will help bring the test to a clinical setting as a laboratory developed test (LDT) by supporting analytical and clinical validation. ALZPath’s chief scientific officer and principal investigator, Dr Andreas Jeromin told Medical Device Network that the LDT version of the assay will be available in Q3 2023.
Results from a study comparing the assay with other traditional tests that use cerebrospinal fluid (CSF) or other plasma biomarkers demonstrated accuracy in detecting AD pathology, though the results have not been peer-reviewed yet.
In late June, the FDA cleared two assays from Roche that detect beta-amyloid and tau from the CSF.
To date, the ADDF has invested nearly $250m to help advance AD treatment and research.
Dr Jeromin told Medical Device Network: “[This investment signifies] the ADDF’s recognition of the critical importance of this diagnostic resource in ensuring access to new disease-modifying treatments for a larger number of patients, including those with early onset Alzheimer’s and members of underserved communities.”
Announcing the funding, Dr Howard Fillit, co-founder and chief science officer at ADDF said: “We know that tau deposits in the brain (as tangles) more closely correlate with cognitive function than beta-amyloid, meaning tau biomarkers will serve as a vital tool for physicians and researchers alike as Alzheimer’s diagnostics and treatments continue to evolve.”
“Non-invasive tau blood tests that are able to accurately quantify the levels of specific types of tau protein in the blood, like ALZpath’s, can impact patient outcomes by aiding in the early diagnosis and intervention for Alzheimer’s disease.”
