Coming on the heels of two failed major studies on promising antibodies designed to fight Alzheimer’s, a new report by researchers from Ruhr-Universität Bochum (RUB), published in the March 2019 edition of the journal Alzheimer’s and Dementia: Diagnosis, Assessment and Disease Monitoring, introduce a new technique.
“This has paved the way for early-stage therapy approaches, where the as yet inefficient drugs on which we had pinned our hopes may prove effective,” said Professor Klaus Gerwert from the Department of Biophysics at RUB.
In patients with Alzheimer’s, the incorrect folding of the amyloid beta protein, mediated by various pathological events, begins as many as 20 years prior to the occurrence of the very first symptoms, at which point therapy is usually ineffective.
First, the research team led by Gerwert developed a blood test which allowed them to detect symptom-free Alzheimer’s in patients approximately eight years before the first inklings of the disorder with an accuracy of 71 per cent.
Unfortunately, the test was also found to be subject to a 9 per cent false positive rate, which made it unsuitable for clinical application.
To address the issue, Gerwert and his colleagues souped up the initial blood test by introducing a second tier. Now, once the at-risk individuals have been identified, they are screened for a dementia-specific biomarker (namely, a tau protein) to confirm the diagnosis.
“Through the combination of both analyses, 87 of 100 Alzheimer’s patients were correctly identified in our study,” explained Gerwert. “And we reduced the number of false positive diagnoses in healthy subjects to 3 of 100. The second analysis is carried out in cerebrospinal fluid that is extracted from the spinal cord.”
With these results, the research team hopes to soon commence clinical trials. In case of success – which here means the safe and reliable detection of Alzheimer’s in a sufficiently early stage – the variety of drugs that are currently ineffective might actually turn out to be beneficial.
Thanks to RUB’s Department of Biophysics, the test has already been fully automated. “We are now conducting in-depth research to detect the second biomarker, namely tau protein, in the blood, in order to supply a solely blood-based test in future,” concludes Klaus Gerwert.