Navigation Links
Flaw in Alzheimer's drug trial test

New research led by Plymouth University Peninsula Schools of Medicine and Dentistry suggests that the cognitive test used in Alzheimer's drug trials is flawed.

The current standard cognitive test for the disease is the ADAS Cog. The new research, published as two studies in Alzheimer's & Dementia: The Journal of the Alzheimer's Association, investigates the role of the test and questions its effectiveness.

The studies show that the ADAS Cog is not subtle enough to properly track changes in the early stages of Alzheimer's. This is important because data from this key stage is required to show whether or not a new drug is working. The study also showed that the modern method of "Rasch analysis" confirmed the flaw.

In their first study, the researchers examined 675 measurements from people, aged 53 to 90, with mild Alzheimer's disease across five time points 0, six, 12, 18 and 24 months. In terms of final patient score the ADAS-cog seemed sound. But by breaking down all the data to component level, a different story emerged. A "ceiling effect" was exposed for eight out of the 11 parts of the ADAS-cog with many patients ranging from 32 to 83 per cent - "passing" the section when in reality much greater variance between the patients almost certainly existed and needed scoring.

In the second study, the research team moved on to use the modern method of "Rasch analysis" to further test the data. This confirmed the flaw. The more sophisticated method of analysis also suggested a number of possible pathways to improvement including making parts of the ADAS-cog test more difficult as well as re-thinking the scoring structure.

As a consequence, the Plymouth-based research team is suggesting urgent changes to the ADAS Cog and is not ruling out the need for a new test.

The study was led by Professor Jeremy Hobart. He said: "It is impossible to say precisely the extent to which the ADAS Cog's flaws have undermined the numerous clinical trials in which it has been used. It has been used, unchanged, for many years and its apparent contribution to suboptimal trials has led a number of drug companies to rethink their strategies. However, it is very clear that in its current form the ADAS Cog underestimates cognitive differences between people and changes over time. To determine if treatments, developed from painstaking years of research, work in expensive studies we need to invest in developing measurement instruments that are fit for purpose. This requires the routine use of different methods. In its current form, the ADAS Cog is not working in people with mild Alzheimer's disease."


Contact: Andrew Gould
University of Plymouth

Related medicine news :

1. A promising clinical trial to reduce the severity of autistic disorders
2. NIH-funded trial launched to assess experimental TB drug
3. Mesothelioma Victims Center Now Offers Its Services To Any Type Of Industrial Worker Diagnosed with Mesothelioma Including Naming the Best Mesothelioma Law Firms
4. Experimental graft-vs.-host disease treatment equivalent to standard care in Phase 3 trial
5. Delkin Devices Inc. Announces SPAN™ Extended Life Cycle Industrial Storage Product Line
6. Winning the battle against leukaemia: Positive early results in clinical trial for DNA vaccine
7. Tamoxifen trial should prompt breast cancer patients to reconsider treatment options
8. Clinical trial at GHSU Cancer Center targets advanced prostate cancer
9. University of Cincinnati leads first trial on steroid and CNI withdrawal post-transplant
10. Kentucky study finds common drug increases deaths in atrial fibrillation patients
11. Edison Pharmaceuticals announces initiation of EPI-743 Phase 2B Leigh Syndrome Clinical Trial
Post Your Comments:
(Date:12/1/2015)... ... December 01, 2015 , ... For many X-rays taken ... for accurate interpretation by the radiologist. The marking utensils are so small, however, ... has found a way to alleviate this problem. , He developed the patent-pending ...
(Date:12/1/2015)... ... ... McLean, VA., December 1, 2015 - Octo Consulting Group, ... development contract to support the National Geospatial-Intelligence Agency's (NGA) IT Services Directorate. ... as well as operations and sustainment support to the NGA’s Agile Web Presence ...
(Date:12/1/2015)... GA (PRWEB) , ... December 01, 2015 , ... ... supports SACC-GA and SACC-USA through membership and leadership since 2008. Gary ... Chair for SACC-USA . Gary has spent a significant amount of time ...
(Date:12/1/2015)... Chicago, IL (PRWEB) , ... December 01, 2015 ... ... the Unified Contact Center Enterprise Authorized Technology Provider (ATP) status from Cisco. This ... sell, deploy and support Cisco Unified Contact Center solutions targeted to the high-end ...
(Date:11/30/2015)... ... December 01, 2015 , ... ... as a 2015-2016 inductee into its VIP Woman of the Year Circle. ... the nation’s leading networking organization exclusively for professional women, boasting 850,000 members and ...
Breaking Medicine News(10 mins):
(Date:12/1/2015)... Sweden , December 1, 2015 ... Cancer Study Group (IBCSG, Bern ) and ... to be part of a state of the art trial, ... --> --> The study, ... treated with anti-hormonal therapy in combination with palbociclib, a cancer ...
(Date:11/30/2015)... BASEL, Switzerland , Dec. 1, 2015 ... through its wholly-owned UK subsidiary Proximagen Ltd., today announced ... novel, oral small molecule inhibitor of Vascular Adhesion Protein ... in the treatment of inflammatory disease. The VAP-1 inhibitor ... --> --> Under the terms ...
(Date:11/30/2015)... Asia,s largest exhibition and conference dedicated to the Medical Device ... 22 nd April 2016. --> --> ... --> -->   --> --> ... population and the government back up, the Medical Device is one of the ... . With the aging population and the government back up, the Medical ...
Breaking Medicine Technology: