Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-25T13:13:21.281Z Has data issue: false hasContentIssue false

Using cognitive decline in novel trial designs for primary prevention and early disease-modifying therapy trials of Alzheimer's disease

Published online by Cambridge University Press:  11 April 2011

David Darby*
Affiliation:
CogState Ltd, Melbourne, Victoria, Australia Florey Neuroscience Institutes, Parkville, Victoria, Australia Centre for Neuroscience, University of Melbourne, Parkville, Victoria, Australia Aged and Residential Care Services, Heidelberg Repatriation Hospital, Austin Health, West Heidelberg, Victoria, Australia
Amy Brodtmann
Affiliation:
Florey Neuroscience Institutes, Parkville, Victoria, Australia Eastern Cognitive Disorders Clinic, Boxhill Hospital, Victoria, Australia
Michael Woodward
Affiliation:
Aged and Residential Care Services, Heidelberg Repatriation Hospital, Austin Health, West Heidelberg, Victoria, Australia
Marc Budge
Affiliation:
Department of Geriatric Medicine, Australian National University Medical School, Canberra, ACT, Australia
Paul Maruff
Affiliation:
CogState Ltd, Melbourne, Victoria, Australia Centre for Neuroscience, University of Melbourne, Parkville, Victoria, Australia
*
Correspondence should be addressed to: David Darby, Chief Medical Officer, CogState Ltd, Level 2, 255 Bourke St, Melbourne VIC 3000, Australia. Phone: +613-9664-1300; Fax: +613-9664-130. Email: [email protected].

Abstract

Background: Ideally putative disease-modifying therapies for Alzheimer's disease (AD) should be tested in patients who have minimal morbidity. Current barriers to such trials in early disease include the lack of disease-specific early biomarkers, insensitivity of quantitative cognitive outcome measures, and expensive trial designs requiring large sample sizes and long duration. This paper describes principles and progress towards a novel trial design that overcomes these problems, utilizing wide-scale cognitive performance screening to define pre-trial cognitive decline trajectories which can serve as trial outcome measures to assess AD disease-modifying efficacy.

Methods: Theoretical principles important for the detection of intra-individual cognitive decline and a practical example are described.

Results: Serial evaluations of community-based volunteers demonstrate how a screening tool method to detect subtle cognitive decline can predict in vivo amyloid pathology as a trigger for etiological evaluation. Trajectories of decline appear consistent over at least two years, suggesting they could be used as a trial inclusion criterion and ameliorable outcome measure together with other AD biomarkers. Informative trial durations could be 6–12 months, or extend to incorporate staggered random withdrawal or start designs, with as few as 20 individuals per treatment arm.

Conclusions: This trial methodology offers significant advantages over current AD trial designs, including treatment at earlier stages of disease, shorter trial duration, obviation of informed consent difficulties, smaller sample sizes, reduced cost and – given adequate screening programs – sufficient subjects for multiple simultaneous trials. Importantly, it allows the rapid evaluation of putative treatments that may only be efficacious in pre-dementia states.

Type
Review Article
Copyright
Copyright © International Psychogeriatric Association 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Arndt, S., Jorge, R., Turvey, C. and Robinson, R. G. (2000a). Adding subjects or adding measurements: which increases the precision of longitudinal research? Journal of Psychiatric Research, 34, 449455.CrossRefGoogle ScholarPubMed
Arndt, S., Turvey, C., Coryell, W. H., Dawson, J. D., Leon, A. C. and Akiskal, H. S. (2000b). Charting patients’ course: a comparison of statistics used to summarize patient course in longitudinal and repeated measures studies. Journal of Psychiatric Research, 34, 105113.CrossRefGoogle ScholarPubMed
Avidan, M. S. et al. (2009). Long-term cognitive decline in older subjects was not attributable to noncardiac surgery or major illness. Anesthesiology, 111, 964970.CrossRefGoogle ScholarPubMed
Butters, M. A. et al. (2008). Imaging Alzheimer pathology in late-life depression with PET and Pittsburgh Compound-B. Alzheimer Disease and Associated Disorders, 22, 261268.CrossRefGoogle ScholarPubMed
Christensen, H. et al. (1999). An analysis of diversity in the cognitive performance of elderly community dwellers: individual differences in change scores as a function of age. Psychology and Aging, 14, 365379.CrossRefGoogle ScholarPubMed
Christensen, H., Dear, K. B., Anstey, K. J., Parslow, R. A., Sachdev, P. and Jorm, A. F. (2005). Within-occasion intraindividual variability and preclinical diagnostic status: is intraindividual variability an indicator of mild cognitive impairment? Neuropsychology, 19, 309317.CrossRefGoogle ScholarPubMed
Collie, A. et al. (2001). Memory decline in healthy older people: implications for identifying mild cognitive impairment. Neurology, 56, 15331538.CrossRefGoogle ScholarPubMed
Collie, A., Maruff, P., Makdissi, M., McCrory, P., McStephen, M. and Darby, D. G. (2003). CogSport: reliability and correlation with conventional cognitive tests used in post-concussion medical examinations. Clinical Journal of Sport Medicine, 13, 2832.CrossRefGoogle Scholar
Collie, A. et al. (2007). Cognitive testing in early-phase clinical trials: development of a rapid computerized test battery and application in a simulated Phase I study. Contemporary Clinical Trials, 28, 391400.CrossRefGoogle Scholar
Cosentino, S. A. et al. (2010). Plasma β-amyloid and cognitive decline. Archives of Neurology, 67, 14851490.CrossRefGoogle ScholarPubMed
Cummings, J. L. (2009). Defining and labeling disease-modifying treatments for Alzheimer's disease. Alzheimers Dementia, 5, 406418.CrossRefGoogle ScholarPubMed
Darby, D. and Walsh, K. (2005). Walsh's Neuropsychology: A Clinical Approach. Edinburgh: Elsevier.Google Scholar
Darby, D., Maruff, P., Collie, A. and McStephen, M. (2002). Mild cognitive impairment can be detected by multiple assessments in a single day. Neurology, 59, 10421046.CrossRefGoogle Scholar
De Jager, C. A., Hogervorst, E., Combrinck, M. and Budge, M. M. (2003). Sensitivity and specificity of neuropsychological tests for mild cognitive impairment, vascular cognitive impairment and Alzheimer's disease. Psychological Medicine, 33, 10391050.CrossRefGoogle ScholarPubMed
De Meyer, G. et al. (2010). Diagnosis-independent Alzheimer disease biomarker signature in cognitively normal elderly people. Archives of Neurology, 67, 949956.CrossRefGoogle ScholarPubMed
Dickerson, B. C. and Sperling, R. A. (2005). Neuroimaging biomarkers for clinical trials of disease-modifying therapies in Alzheimer's disease. NeuroRx, 2, 348360.CrossRefGoogle ScholarPubMed
Doody, R. S. et al. (2009). Donepezil treatment of patients with MCI: a 48-week randomized, placebo-controlled trial. Neurology, 72, 15551561.CrossRefGoogle ScholarPubMed
Dubois, B. et al. (2007). Research criteria for the diagnosis of Alzheimer's disease: revising the NINCDS-ADRDA criteria. Lancet Neurology, 6, 734746.CrossRefGoogle ScholarPubMed
Dubois, B. et al. (2010). Revising the definition of Alzheimer's disease: a new lexicon. Lancet Neurology, 9, 11181127.CrossRefGoogle ScholarPubMed
Esiri, M. M., Nagy, Z., Smith, M. Z., Barnetson, L. and Smith, A. D. (1999). Cerebrovascular disease and threshold for dementia in the early stages of Alzheimer's disease. Lancet, 354, 919920.CrossRefGoogle ScholarPubMed
Falleti, M. G., Maruff, P., Collie, A., Darby, D. G. and McStephen, M. (2003). Qualitative similarities in cognitive impairment associated with 24 h of sustained wakefulness and a blood alcohol concentration of 0.05%. Journal of Sleep Research, 12, 265274.CrossRefGoogle Scholar
Falleti, M. G., Maruff, P., Collie, A. and Darby, D. G. (2006). Practice effects associated with the repeated assessment of cognitive function using the CogState battery at 10-minute, one week and one month test-retest intervals. Journal of Clinical and Experimental Neuropsychology, 28, 10951112.CrossRefGoogle ScholarPubMed
Ferris, S. H. et al. (2006). ADCS Prevention Instrument Project: overview and initial results. Alzheimer Disease and Associated Disorders, 20, S109S123.CrossRefGoogle ScholarPubMed
Fredrickson, J. et al. (2009). Evaluation of the usability of a brief computerized cognitive screening test in older people for epidemiological studies. Neuroepidemiology, 34, 6575.CrossRefGoogle ScholarPubMed
Gauthier, S. (2009). Will CSF analysis become routine in people with memory complaints? Lancet Neurology, 8, 595596.CrossRefGoogle ScholarPubMed
Hampel, H., Broich, K., Hoessler, Y. and Pantel, J. (2009). Biological markers for early detection and pharmacological treatment of Alzheimer's disease. Dialogues in Clinical Neuroscience, 11, 141157.CrossRefGoogle ScholarPubMed
Holtzer, R., Verghese, J., Wang, C., Hall, C. B. and Lipton, R. B. (2008). Within-person across-neuropsychological test variability and incident dementia. JAMA, 300, 823830.CrossRefGoogle ScholarPubMed
Jagust, W. J. et al. (2009). Relationships between biomarkers in aging and dementia. Neurology, 73, 11931199.CrossRefGoogle ScholarPubMed
Khachaturian, Z. S. et al. (2009). A roadmap for the prevention of dementia. II: Leon Thal Symposium 2008. Alzheimers Dementia, 5, 8592.CrossRefGoogle ScholarPubMed
Kokjohn, T. A. and Roher, A. E. (2009). Amyloid precursor protein transgenic mouse models and Alzheimer's disease: understanding the paradigms, limitations, and contributions. Alzheimers Dementia, 5, 340347.CrossRefGoogle ScholarPubMed
Luque, F. A. and Jaffe, S. L. (2009). The molecular and cellular pathogenesis of dementia of the Alzheimer's type an overview. International Review of Neurobiology, 84, 151165.CrossRefGoogle ScholarPubMed
Maruff, P. (2008). Validity of the CogState computerized cognitive test battery: sensitivity to mild traumatic brain injury, mild cognitive impairment, schizophrenia and AIDS dementia complex. Archives of Clinical Neuropsychology, 24, 165178.CrossRefGoogle Scholar
Maruff, P., Collie, A., Darby, D., Weaver-Cargin, J. and McStephen, M. (2004). Subtle memory decline over 12 months in mild cognitive impairment. Dementia and Geriatric Cognitive Disorders, 18, 342348.CrossRefGoogle ScholarPubMed
Mattsson, N., Blennow, K. and Zetterberg, H. (2009). CSF biomarkers: pinpointing Alzheimer pathogenesis. Annals of the New York Academy of Science, 1180, 2835.CrossRefGoogle ScholarPubMed
McAlpine, F. E. et al. (2009). Inhibition of soluble TNF signaling in a mouse model of Alzheimer's disease prevents pre-plaque amyloid-associated neuropathology. Neurobiological Disorders, 34, 163177.Google Scholar
Middleton, L. E. and Yaffe, K. (2009). Promising strategies for the prevention of dementia. Archives of Neurology, 66, 12101215.CrossRefGoogle ScholarPubMed
Morris, J. C. et al. (2009). Pittsburgh compound B imaging and prediction of progression from cognitive normality to symptomatic Alzheimer disease. Archives of Neurology, 66, 14691475.CrossRefGoogle ScholarPubMed
Morris, M. C., Evans, D. A., Hebert, L. E. and Bienias, J. L. (1999). Methodological issues in the study of cognitive decline. American Journal of Epidemiology, 149, 789793.CrossRefGoogle Scholar
Nimmrich, V. and Ebert, U. (2009). Is Alzheimer's disease a result of presynaptic failure? Synaptic dysfunctions induced by oligomeric beta-amyloid. Review of Neuroscience, 20, 112.CrossRefGoogle ScholarPubMed
Petersen, R. C., Smith, G., Kokmen, E., Ivnik, R. J. and Tangalos, E. G. (1992). Memory function in normal aging. Neurology, 42, 396401.CrossRefGoogle ScholarPubMed
Pike, K. E. et al. (2007). Beta-amyloid imaging and memory in non-demented individuals: evidence for preclinical Alzheimer's disease. Brain, 130, 28372844.CrossRefGoogle ScholarPubMed
Qiu, C., Kivipelto, M. and von Strauss, E. (2009). Epidemiology of Alzheimer's disease: occurrence, determinants, and strategies toward intervention. Dialogues in Clinical Neuroscience, 11, 111128.CrossRefGoogle ScholarPubMed
Rafii, M. S. and Aisen, P. S. (2009). Recent developments in Alzheimer's disease therapeutics. BMC Medicine, 7, 7.CrossRefGoogle ScholarPubMed
Reiman, E. M., Langbaum, J. B. and Tariot, P. (2010). Alzheimer's prevention initiative: a proposal to evaluate presymptomatic treatments as quickly as possible. Biomarkers in Medicine, 4, 314CrossRefGoogle Scholar
Rowe, C. C. et al. (2007). Imaging beta-amyloid burden in aging and dementia. Neurology, 68, 17181725.CrossRefGoogle ScholarPubMed
Salloway, S. et al. (2009). A phase 2 multiple ascending dose trial of bapineuzumab in mild to moderate Alzheimer disease. Neurology, 73, 20522053.CrossRefGoogle ScholarPubMed
Salthouse, T. A. (2009). When does age-related cognitive decline begin? Neurobiological Aging, 30, 507514.CrossRefGoogle ScholarPubMed
Schenk, D. et al. (1999). Immunization with amyloid-beta attenuates Alzheimer-disease-like pathology in the PDAPP mouse. Nature, 400, 173177.CrossRefGoogle ScholarPubMed
Schneider, L. S. and Sano, M. (2009). Current Alzheimer's disease clinical trials: methods and placebo outcomes. Alzheimers Dementia, 5, 388397.CrossRefGoogle ScholarPubMed
Schuff, N. et al. (2009). MRI of hippocampal volume loss in early Alzheimer's disease in relation to ApoE genotype and biomarkers. Brain, 132, 10671077.CrossRefGoogle ScholarPubMed
Silbert, B. S., Scott, D. A., Evered, L. A., Lewis, M. S. and Maruff, P. T. (2007). Preexisting cognitive impairment in patients scheduled for elective coronary artery bypass graft surgery. Anesthesia and Analgesia, 104, 10231028.CrossRefGoogle ScholarPubMed
Spires-Jones, T. L. et al. (2009). Passive immunotherapy rapidly increases structural plasticity in a mouse model of Alzheimer disease. Neurobiological Disorders, 33, 213220.Google Scholar
Thal, L. J. et al. (2006). The role of biomarkers in clinical trials for Alzheimer disease. Alzheimer Disease and Associated Disorders, 20, 615.CrossRefGoogle ScholarPubMed
Villemagne, V. L. et al. (2008). Abeta deposits in older non-demented individuals with cognitive decline are indicative of preclinical Alzheimer's disease. Neuropsychologia, 46, 16881697.CrossRefGoogle ScholarPubMed
Weaver Cargin, J., Maruff, P., Collie, A. and Masters, C. (2006). Mild memory impairment in healthy older adults is distinct from normal aging. Brain Cognition, 60, 146155.CrossRefGoogle ScholarPubMed
Weintraub, S., Powell, D. H. and Whitla, D. K. (1994). Successful cognitive aging: individual differences among physicians on a computerized test of mental state. Journal of Geriatric Psychiatry, 28, 1534.Google Scholar
Wilson, R. S., Hebert, L. E., Scherr, P. A., Barnes, L. L., Mendes de Leon, C. F. and Evans, D. A. (2009). Educational attainment and cognitive decline in old age. Neurology, 72, 460465.CrossRefGoogle ScholarPubMed
Yaffe, K. et al. (2009). Predictors of maintaining cognitive function in older adults: the Health ABC study. Neurology, 72, 20292035.CrossRefGoogle ScholarPubMed