Advertisement
News
Advertisement

DiaGenic show 82% accuracy of new ADtect blood test in Alzheimer’s disease

Wed, 07/18/2012 - 3:11pm

OSLO, Norway--(BUSINESS WIRE)--Regulatory News:DiaGenic ASA [OSL:DIAG] today  presented a significant improvement in overall accuracy of a new version of its patented, CE marked product ADtect® test at the International Alzheimer’s Associations International conference (IAAC) in Vancouver, Canada. The new data, representing the fourth independent patient study to improve ADtect® for blood based diagnosis of Alzheimer’s disease (AD), reveals an accuracy of 82% of AD dementia versus matched control patients.

The higher diagnostic accuracy is obtained from read out of only 20 genes derived from the patented and CE marked ADtect® which contains a larger (96) set of genes relevant for the diagnosis of Alzheimer’s Disease dementia. The same select 20 genes were also tested in two cohorts of patients with amnestic Mild Cognitive Impairment (MCI) that within 2 years developed AD (MCI/AD) and showed a prediction accuracy for MCI/AD of 70 - 74% versus matched stable MCI (MCI that did not convert to AD). An additional separate 25 non-overlapping gene signature with improved overall prediction was identified predicting conversion from MCI to AD (MCI/AD) with accuracy of 81%.

The DiaGenic results released today at AAIC supports the previous findings that pre-dementia and dementia stages of Alzheimer’s disease (AD) can be identified with a low number of genes in blood evidenced by several independent studies. Conversion from MCI to Alzheimers disease dementia occurs at a rate of about 15% per year and a simple blood test allowing for early diagnosis of Alzheimers disease that is already in the pre-dementia stage is of significant clinical interest.

The increased accuracy of the new ADtect® reported at AAIC was obtained through a systematic investigation that started with 1152 genes, successively selecting only informative genes utilized in the previously approved ADtect® which includes 96 genes, to a 20 gene set for the improved ADtect®. This selection process was done with new bioinformatic algorithms running all patient samples on a new qPCR platform from Life Technologies.

Patient samples in the reported 4thstudy included 25 patients with dementia in AD, 25 matched controls and 75 patients with MCI. This represents an extension of DiaGenic’s previous validation cohorts of more than 500 AD and MCI patients. Improved assay methodology and instrumentation is believed to represent a significant part of the accuracy improvement of the lower number of gene probes used to detect Alzheimer’s disease in the dementia and the pre-dementia stage.

“The need for a blood test for Alzheimer’s disease, especially in the pre-symptomatic stage, is urgent in view of the increasing number of at risk patients globally and the promise of preventative therapy. Many patients living outside major research centers will not be able to take advantage of the advances in spinal fluid biomarkers or neuroimaging. The improvements made by DiaGenic in their ADtect® test and also in accurately identifying which patients with MCI convert to AD represent significant steps forward in developing a blood test for diagnosing this debilitating disease, says Professor Sam Gandy, Mount Sinai School of Medicine, New York, US”, an advisor to DiaGenic, commenting on the company’s presentation at the AAIC.

In addition to correctly predicting Alzheimers disease in the dementia stage with 82% accuracy, the same 20 gene signature has previously been shown to detect MCI that within 2 years convert to Alzheimer disease dementia in a study that included 30 stable MCI and 30 MCI converting to AD dementia, with a total prediction accuracy of 74% (poster presentation at the CTAD conference in San Diego November 2011).

Utilizing the improved assay methodology and instrumentation, a separate non-overlapping subset of 25 genes increased the prediction accuracy of MCI that convert to dementia in Alzheimer’s disease to 81%. The predictive gene signature was derived from blood samples collected from a total of 75 MCI patients.  

DiaGenic also observe similar prediction accuracy when applying different independent biometrical methods on the qPCR data. Artificial Neural Network (ANN) and Partial Least Square (PLS) yielded similar results on accuracy.

The improved accuracy in detecting Alzheimer’s Disease, above 80%, using 20-25 informative genes, represents a major step in the direction of diagnostic utility with a substantial reduction in the number of qPCR reactions (gene signal read outs) and potential simplifications in both the bioanalytical algorithms and the qPCR platform used, as needed for the diagnosis of Alzheimer’s Disease.

The reduction in the number of multiplex reactions down to 20-25 genes may allow for application of the DiaGenic proprietary Alzheimer’s Disease diagnostic gene signature on many other technical platforms which deploy a more limited set of multiplex reactions, resulting in increased competitiveness and clinical utility compared to more costly, complex and invasive methods used to detect Alzheimer’s disease.

“The finding of a low number of genes being able to pick up both Alzheimers disease in the dementia stage and Mild Cognitive Impairment due to AD, with high accuracy, is indeed promising. A blood based approach clearly has the advantage of being simple, mildly invasive and globally accessible and may be just the right tool needed to allow for early intervention with disease modifying therapy. It is now important to compare this new blood test with CSF biomarkers and PET imaging to develop highly accurate and cost efficient algorithms for diagnosing Alzheimer’s disease and stages thereof, says Professor Bengt Winblad, Karolinska Institutet, Sweden”

Affiliations to DiaGenic ASA
Professor Sam Gandy, Mount Sinai School of Medicine, New York, US and Professor Bengt Winblad, Karolinska Institutet, Sweden are members of the Scientific Advisory Board of DiaGenic ASA

About DiaGenic ASA
DiaGenic seeks to create value for patients, partners, and investors by developing innovative and more patient friendly methods for early detection of diseases utilizing DiaGenic’s unique concept. The concept implies that a disease evokes systemic responses in the blood unique for the disease, and which can be measured by using blood samples.

DiaGenic is a world leader in identifying these gene expression signatures in peripheral blood and is focused on the development of biomarkers in the field of Alzheimer’s disease and Parkinson’s disease. DiaGenic’s Alzheimer’s disease development program includes the CE marked diagnostic test ADtect®, for detection of mild to moderate Alzheimer’s disease, and MCItect®which is under development for identifying patients with very early stages of Alzheimer’s disease (prodromal AD).

DiaGenic’s concept is protected through an extensive patent portfolio. DiaGenic promotes its products and services towards leading pharmaceutical, imaging and diagnostic companies. DiaGenic is located in Norway and listed on the Oslo Stock Exchange. For more information please visit: www.diagenic.com

This information was brought to you by Cision http://www.cisionwire.com

 

Advertisement

Share this Story

X
You may login with either your assigned username or your e-mail address.
The password field is case sensitive.
Loading