|
|
||||||||
From the Departments of Diagnostic Radiology (Drs. Jack, Xu, and Felmlee, and K. Stewart and M. Shiung), Neurology (Drs. Knopman and Petersen), and Biostatistics (Dr. OBrien and R. Cha), Mayo Clinic and Foundation, Rochester, MN; and Pharmaceutical Research (Drs. Gracon, Hoover, and Slomkowski), Parke-Davis (Pfizer), Ann Arbor, MI.
Address correspondence and reprint requests to Dr. Clifford R. Jack, Jr., Mayo Clinic, Diagnostic Radiology, 200 First Street SW, Rochester, MN 55905; e-mail: jack.clifford{at}mayo.edu
Objective: To assess the feasibility of using MRI measurements as a surrogate endpoint for disease progression in a therapeutic trial for AD.
Methods: A total of 362 patients with probable AD from 38 different centers participated in the MRI portion of a 52-week randomized placebo-controlled trial of milameline, a muscarinic receptor agonist. The therapeutic trial itself was not completed due to projected lack of efficacy on interim analysis; however, the MRI arm of the study was continued. Of the 362 subjects who underwent a baseline MRI study, 192 subjects underwent a second MRI 1 year later. Hippocampal volume and temporal horn volume were measured from the MRI scans.
Results: The annualized percent changes in hippocampal volume (-4.9%) and temporal horn volume (16.1%) in the study patients were consistent with data from prior single-site studies. Correlations between the rate of MRI volumetric change and change in behavioral/cognitive measures were greater for the temporal horn than for the hippocampus. Decline over time was more consistently seen with imaging measures, 99% of the time for the hippocampus, than behavioral/cognitive measures (p < 0.001). Greater consistency in MRI than behavioral/clinical measures resulted in markedly lower estimated sample size requirements for clinical trials. The estimated number of subjects per arm required to detect a 50% reduction in the rate of decline over 1 year are: AD Assessment Scalecognitive subscale 320; Mini-Mental Status Examination 241; hippocampal volume 21; temporal horn volume 54.
Conclusion: The consistency of MRI measurements obtained across sites, and the consistency between the multisite milameline data and that obtained in prior single-site studies, demonstrate the technical feasibility of using structural MRI measures as a surrogate endpoint of disease progression in therapeutic trials. However, validation of imaging as a biomarker of therapeutic efficacy in AD awaits a positive trial.
This article has been cited by other articles:
![]() |
R Schmidt, S Ropele, B Pendl, P Ofner, C Enzinger, H Schmidt, A Berghold, M Windisch, H Kolassa, and F Fazekas Longitudinal multimodal imaging in mild to moderate Alzheimer disease: a pilot study with memantine J. Neurol. Neurosurg. Psychiatry, December 1, 2008; 79(12): 1312 - 1317. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. S. Fleisher, S. Sun, C. Taylor, C. P. Ward, A. C. Gamst, R. C. Petersen, C. R. Jack Jr, P. S. Aisen, L. J. Thal, and For the Alzheimer's Disease Cooperative Study Volumetric MRI vs clinical predictors of Alzheimer disease in mild cognitive impairment Neurology, January 15, 2008; 70(3): 191 - 199. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. L. Cummings, R. Doody, and C. Clark Disease-modifying therapies for Alzheimer disease: Challenges to early intervention Neurology, October 16, 2007; 69(16): 1622 - 1634. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Li, F. Shi, F. Pu, X. Li, T. Jiang, S. Xie, and Y. Wang Hippocampal Shape Analysis of Alzheimer Disease Based on Machine Learning Methods AJNR Am. J. Neuroradiol., August 1, 2007; 28(7): 1339 - 1345. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. H. Ridha, J. Barnes, L. A. van de Pol, J. M. Schott, R. G. Boyes, M. M. Siddique, M. N. Rossor, P. Scheltens, and N. C. Fox Application of Automated Medial Temporal Lobe Atrophy Scale to Alzheimer Disease Arch Neurol, June 1, 2007; 64(6): 849 - 854. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. L. Whitwell, C. R. Jack Jr, J. E. Parisi, D. S. Knopman, B. F. Boeve, R. C. Petersen, T. J. Ferman, D. W. Dickson, and K. A. Josephs Rates of cerebral atrophy differ in different degenerative pathologies Brain, April 1, 2007; 130(4): 1148 - 1158. [Abstract] [Full Text] [PDF] |
||||
![]() |
F.L. Giesel, H.K. Hahn, P.A. Thomann, E. Widjaja, E. Wignall, H. von Tengg-Kobligk, J. Pantel, P.D. Griffiths, H.O. Peitgen, J. Schroder, et al. Temporal Horn Index and Volume of Medial Temporal Lobe Atrophy Using a New Semiautomated Method for Rapid and Precise Assessment AJNR Am. J. Neuroradiol., August 1, 2006; 27(7): 1454 - 1458. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. M. Schott, S. L. Price, C. Frost, J. L. Whitwell, M. N. Rossor, and N. C. Fox Measuring atrophy in Alzheimer disease: A serial MRI study over 6 and 12 months Neurology, July 12, 2005; 65(1): 119 - 124. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. C. Fox, R. S. Black, S. Gilman, M. N. Rossor, S. G. Griffith, L. Jenkins, M. Koller, and for the AN1792(QS-21)-201 Study Team Effects of A{beta} immunization (AN1792) on MRI measures of cerebral volume in Alzheimer disease Neurology, May 10, 2005; 64(9): 1563 - 1572. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. L. Cummings Searching for Methods to Detect, Prevent, and Treat Alzheimer's Disease Am J Psychiatry, April 1, 2005; 162(4): 645 - 647. [Full Text] [PDF] |
||||
![]() |
B. F. Boeve, I. W. Tremont-Lukats, A. J. Waclawik, J. R. Murrell, B. Hermann, C. R. Jack Jr, M. M. Shiung, G. E. Smith, A. R. Nair, N. Lindor, et al. Longitudinal characterization of two siblings with frontotemporal dementia and parkinsonism linked to chromosome 17 associated with the S305N tau mutation Brain, April 1, 2005; 128(4): 752 - 772. [Abstract] [Full Text] [PDF] |
||||
![]() |
O. P Dall'Igna, D. O Souza, and D. R Lara Caffeine as a Neuroprotective Adenosine Receptor Antagonist Ann. Pharmacother., April 1, 2004; 38(4): 717 - 718. [Full Text] [PDF] |
||||
![]() |
C. R. Jack Jr., M. M. Shiung, J. L. Gunter, P. C. O'Brien, S. D. Weigand, D. S. Knopman, B. F. Boeve, R. J. Ivnik, G. E. Smith, R. H. Cha, et al. Comparison of different MRI brain atrophy rate measures with clinical disease progression in AD Neurology, February 24, 2004; 62(4): 591 - 600. [Abstract] [Full Text] [PDF] |
||||
![]() |
C.A. Luis, D.A. Loewenstein, A. Acevedo, W.W. Barker, and R. Duara Mild cognitive impairment: Directions for future research Neurology, August 26, 2003; 61(4): 438 - 444. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |