Dataset Information

Longitudinal plasma amyloid beta in Alzheimer's disease clinical trials.

ABSTRACT:

Introduction

Little is known about the utility of plasma amyloid beta (Aβ) in clinical trials of Alzheimer's disease (AD).

Methods

We analyzed longitudinal plasma samples from two large multicenter clinical trials: (1) donezepil and vitamin E in mild cognitive impairment (n = 405, 24 months) and (2) simvastatin in mild to moderate AD (n = 225, 18 months).

Results

Baseline plasma Aβ was not related to cognitive or clinical progression. We observed a decrease in plasma Aβ40 and 42 among apolipoprotein E epsilon 4 (APOE ε4) carriers relative to noncarriers in the mild cognitive impairment trial. Patients treated with simvastatin showed a significant increase in Aβ compared with placebo. We found significant storage time effects and considerable plate-to-plate variation.

Discussion

We found no support for the utility of plasma Aβ as a prognostic factor or correlate of cognitive change. Analysis of stored specimens requires careful standardization and experimental design, but plasma Aβ may prove useful in pharmacodynamic studies of antiamyloid drugs.

SUBMITTER: Donohue MC

PROVIDER: S-EPMC4387108 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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Publications

Longitudinal plasma amyloid beta in Alzheimer's disease clinical trials.

Donohue Michael C MC Moghadam Setareh H SH Roe Allyson D AD Sun Chung-Kai CK Edland Steven D SD Thomas Ronald G RG Petersen Ronald C RC Sano Mary M Galasko Douglas D Aisen Paul S PS Rissman Robert A RA

Alzheimer's & dementia : the journal of the Alzheimer's Association 20141007 9

<h4>Introduction</h4>Little is known about the utility of plasma amyloid beta (Aβ) in clinical trials of Alzheimer's disease (AD).<h4>Methods</h4>We analyzed longitudinal plasma samples from two large multicenter clinical trials: (1) donezepil and vitamin E in mild cognitive impairment (n = 405, 24 months) and (2) simvastatin in mild to moderate AD (n = 225, 18 months).<h4>Results</h4>Baseline plasma Aβ was not related to cognitive or clinical progression. We observed a decrease in plasma Aβ40 a ...[more]

PMID: 25301682

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Dataset Information

Longitudinal plasma amyloid beta in Alzheimer's disease clinical trials.

Introduction

Methods

Results

Discussion

Publications

Longitudinal plasma amyloid beta in Alzheimer's disease clinical trials.

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