Alzheimer Disease: Farlow M

Farlow M. · Department of Neurology, Indiana University School of Medicine, Indianapolis, Indiana 46202-5111, USA. · Int Psychogeriatr. · Pubmed #12636182 No free full text.

Abstract: This review provides an overview of the three most widely used cholinesterase (ChE) inhibitors: donepezil, rivastigmine, and galantamine. Differences in pharmacologic profiles will be discussed, and consideration will be given to how such differences may relate to and influence the clinical efficacy and tolerability of the various agents. In addition to providing cognitive benefits in patients with Alzheimer's disease (AD), growing clinical evidence also suggests that ChE inhibitors can produce favorable and clinically relevant effects on neuropsychiatric/behavioral disturbances and activities of daily living. Furthermore, recent data indicate that these agents may be effective at all levels of disease severity and for all rates of disease progression. The clinical utility of ChE inhibitors in a wider spectrum of dementias which share a common cholinergic deficit, such as Lewy body dementia, Parkinson's disease dementia, and vascular dementia, is currently under investigation. Beyond symptomatic relief, data suggest that ChE inhibitors may also slow the underlying disease process. As clinical and research experience with these agents continues to accumulate, the differences in their effects will become more apparent and will help physicians tailor ChE inhibition treatment to the needs of the individual patient.

Feldman HH, Ferris S, Winblad B, Sfikas N, Mancione L, He Y, Tekin S, Burns A, Cummings J, del Ser T, Inzitari D, Orgogozo JM, Sauer H, Scheltens P, Scarpini E, Herrmann N, Farlow M, Potkin S, Charles HC, Fox NC, Lane R. · Division of Neurology, University of British Columbia Hospital, Vancouver, Canada. · Lancet Neurol. · Pubmed #17509485 No free full text.

Abstract: OBJECTIVE: To assess the effect of rivastigmine in patients with mild cognitive impairment (MCI) on the time to clinical diagnosis of Alzheimer's disease (AD) and the rate of cognitive decline. METHODS: The study was a double-blind, randomised, placebo-controlled trial of up to 48 months. All patients had MCI operationally defined by having cognitive symptoms, a global clinical dementia rating stage of 0.5, a score of less than 9 on the New York University delayed paragraph recall test, and by not meeting the diagnostic criteria for AD. Primary efficacy variables were time to clinical diagnosis of AD, and change in performance on a cognitive test battery. This study is registered with the US National Institutes of Health clinical trials database (ClinicalTrials.gov), number NCT00000174. FINDINGS: Of 1018 study patients enrolled, 508 were randomly assigned to rivastigmine and 510 to placebo; 17.3% of patients on rivastigmine and 21.4% on placebo progressed to AD (hazard ratio 0.85 [95% CI 0.64-1.12]; p=0.225). There was no significant difference between the rivastigmine and placebo groups on the standardised Z score for the cognitive test battery measured as mean change from baseline to endpoint (-0.10 [95% CI -0.63 to 0.44], p=0.726). Serious adverse events were reported by 141 (27.9%) rivastigmine-treated patients and 155 (30.5%) patients on placebo; adverse events of all types were reported by 483 (95.6%) rivastigmine-treated patients and 472 (92.7%) placebo-treated patients. The predominant adverse events were cholinergic: the frequencies of nausea, vomiting, diarrhoea, and dizziness were two to four times higher in the rivastigmine group than in the placebo group. INTERPRETATION: There was no significant benefit of rivastigmine on the progression rate to AD or on cognitive function over 4 years. The overall rate of progression from MCI to AD in this randomised clinical trial was much lower than predicted. Rivastigmine treatment was not associated with any significant safety concerns.

Siemers E, Skinner M, Dean RA, Gonzales C, Satterwhite J, Farlow M, Ness D, May PC. · Lilly Research Laboratories, Indianapolis, Indiana 46285, USA. · Clin Neuropharmacol. · Pubmed #15965311 No free full text.

Abstract: Amyloid beta (Abeta) may play a central role in the pathogenesis of Alzheimer disease. A functional gamma-secretase inhibitor, LY450139, was developed that inhibits Abeta formation in whole cell assays, transgenic mice, and beagle dogs. The authors wished to determine the safety and tolerability of this drug, and the reduction of Abeta in plasma and cerebrospinal fluid (CSF) after multiple doses. Volunteer subjects (N = 37) were studied using doses from 5 to 50 mg/day given for 14 days. Plasma and CSF concentrations of LY450139, Abeta(1-40) and Abeta(1-X) ("Abeta(total)") were determined, and safety and tolerability were assessed. The plasma half-life of LY450139 was approximately 2.5 hours. Pharmacokinetic analyses showed a linear relationship between dose and plasma concentrations, with a Cmax of 828 +/- 19.2 ng/mL after a 50-mg dose. Plasma Abeta concentrations decreased in a dose-dependent manner over a 6-hour interval following drug administration, with a maximum decrease of approximately 40% relative to baseline. After returning to baseline, Abeta concentrations were transiently increased. CSF Abeta concentrations were unchanged. Adverse events reported by subjects taking 5-mg, 20-mg, or 40-mg doses were similar to those reported by subjects taking placebo. Two of 7 subjects taking 50 mg/day experienced adverse events that may have been drug related. In this phase 1 volunteer study, reported adverse events after taking LY450139 were manageable. A dose-dependent reduction in plasma Abeta was demonstrated, and changes in plasma Abeta concentrations were temporally related to the pharmacokinetic characteristics of LY450139.

Kurz A, Farlow M, Quarg P, Spiegel R. · Technische Universität München, Munich, Germany. · Alzheimer Dis Assoc Disord. · Pubmed #15494617 No free full text.

Abstract: The efficacy and tolerability of the cholinesterase inhibitor rivastigmine in the treatment of Alzheimer disease (AD) have been demonstrated in several clinical trials, which included patients with a wide range of dementia severities. To investigate the association between severity of disease and treatment response, the combined data from three large randomized, placebo-controlled trials were analyzed. The pooled patient population was stratified into three cohorts showing moderately severe (Mini-Mental State Examination score [MMSE] < or = 15), moderate (MMSE 16-22), and mild (MMSE > or = 22) dementia. In each cohort, the effects of rivastigmine 6 to 12 mg/day versus placebo were evaluated using the cognitive subscale of the Alzheimer Disease Assessment Scale (ADAS-cog) and the Progressive Deterioration Scale. Rivastigmine 6 to 12 mg/day maintained ADAS-cog scores at or above placebo levels in all cohorts, while cognitive deterioration with placebo was progressive and severity dependent. Activities of daily living showed statistically significant benefits with rivastigmine across all severity cohorts.

Dodel RC, Du Y, Depboylu C, Hampel H, Frölich L, Haag A, Hemmeter U, Paulsen S, Teipel SJ, Brettschneider S, Spottke A, Nölker C, Möller HJ, Wei X, Farlow M, Sommer N, Oertel WH. · Department of Neurology, Friedrich-Wilhelms-University, Sigmund-Freudstr. 25, 53105 Bonn, Germany. · J Neurol Neurosurg Psychiatry. · Pubmed #15377700 links to  free full text

Abstract: OBJECTIVE: Active or passive immunisation can mitigate plaque pathology in murine models of Alzheimer's disease (AD). Recently, it has been shown that antibodies against beta-amyloid (Abeta) are present in human immunoglobulin preparations (IVIgG), which specifically recognise and inhibit the neurotoxic effects of Abeta. This study reports the results from a pilot study using IVIgG in patients with AD. METHODS: Five patients with AD were enrolled and received monthly IVIgG over a 6 month period. Efficacy assessment included total Abeta/Abeta(1-42) measured in the CSF/serum as well as effects on cognition (ADAS-cog; CERAD) at baseline and at 6 months following IVIgG. RESULTS: Following IVIgG, total Abeta levels in the CSF decreased by 30.1% (17.3-43.5%) compared to baseline (p<0.05). Total Abeta increased in the serum by 233% (p<0.05). No significant change was found in Abeta(1-42) levels in the CSF/serum. Using ADAS-cog, an improvement of 3.7+/-2.9 points was detected. Scores in the MMSE were essentially unchanged (improved in four patients, stable in one patient) following IVIgG compared to baseline. CONCLUSION: Although the sample size of this pilot study is too small to draw a clear conclusion, the results of this pilot study provide evidence for a more detailed investigation of IVIgG for the treatment of AD.

Farlow M, Potkin S, Koumaras B, Veach J, Mirski D. · Department of Neurology, Indiana University School of Medicine, Indianapolis 46202, USA. · Arch Neurol. · Pubmed #12810489 links to  free full text

Abstract: BACKGROUND: Treatment with cholinesterase inhibitors improves cognition in patients with Alzheimer disease (AD). In studies designed with a washout period at the end of the study, after treatment with a cholinesterase inhibitor is discontinued, the cognitive benefits of therapy are no longer apparent following washout. The rivastigmine trials discussed in this article were not designed with a posttreatment washout period at the end of the study. Therefore, to evaluate the effect of discontinuing treatment, we analyzed the retrieved dropout (RDO) population. OBJECTIVE: To evaluate the change in cognition (at week 26 vs baseline) observed in patients from 3 large clinical trials of AD who prematurely discontinued treatment with placebo or rivastigmine.Design and METHODS: Eligible patients with AD (Mini-Mental State Examination [MMSE] score, 10-26, inclusive) were enrolled in 1 of three 26-week, double-blind, placebo-controlled studies (Novartis US Pivotal [dose-range] Trial, US fixed-dose study, and a Global Pivotal [dose-range] Trial) that compared rivastigmine therapy with placebo. Patients who discontinued study participation (for any reason) (considered to be the RDO population) were encouraged to return for their scheduled week 26 efficacy evaluations. Effects on cognition were assessed using the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog). RESULTS: The results for the Novartis US Pivotal Trials and for the 3 studies combined (Novartis studies B352, B351, and B303) are reported. In the US pivotal trial, RDO patients in the 6- to 12-mg/d group had been not receiving the drug (to be called "off drug") for 102 (57.7) days (mean [SD]) compared with 68 (51.7) days in the RDO placebo group. In these RDO analyses, a statistically significantly greater worsening on the ADAS-Cog mean change score was observed in the placebo group (n = 17) compared with the rivastigmine 6- to 12-mg/d group (n = 33) at week 26 (MMSE score, -8.2 vs -3.0; P =.009). In the pooled studies, the mean (SD) number of days off treatment was 95 (52.0) days for the rivastigmine 6- to 12-mg/d group and 66 (52.7) days for the placebo group. The RDO analysis also showed a statistically significantly greater decline in cognitive function as measured by the ADAS-Cog mean change score in the placebo group (n = 38) compared with the rivastigmine 6- to 12-mg/d group (n = 88) at week 26 (MMSE score, -5.69 vs -2.5; P =.004). A significantly greater proportion of patients in the placebo group exhibited at least a 4-point and 7-point worsening in ADAS-Cog scores at week 26 compared with the rivastigmine 6- to 12-mg/d group in both the Novartis US Pivotal Trials (P =.007, P =.009) and the pooled studies (P =.002, P =.017). CONCLUSIONS: After discontinuation of therapy, rivastigmine-treated patients exhibited less deterioration in cognitive function compared with placebo-treated patients. The less severe worsening of cognition after withdrawal of treatment in patients previously treated with rivastigmine suggests an effect on disease progression.

Grundman M, Capparelli E, Kim HT, Morris JC, Farlow M, Rubin EH, Heidebrink J, Hake A, Ho G, Schultz AN, Schafer K, Houston W, Thomas R, Thal LJ, Anonymous00006. · Department of Neurosciences, University of California-San Diego, 9500 Gilman, La Jolla, CA 92093, USA. · Life Sci. · Pubmed #12770610 No free full text.

Abstract: A phase 1, randomized, double-blind, placebo-controlled, dose escalation study of the purine derivative, AIT-082 (Neotrofin, NeoTherapeutics) was conducted in mild Alzheimer's disease (AD) patients to evaluate multiple-dose safety, tolerability, and pharmacokinetics. Possible short-term effects of AIT-082 on cognition and memory were preliminarily investigated. AIT-082 is currently being developed as a potential treatment for Alzheimer's disease and other neurological disorders. Pre-clinical studies indicate that AIT-082 has memory enhancing properties, stimulates neuritogenesis and the production of neurotrophic factors. Patients received an oral dose of AIT-082 or placebo daily for one week. Thirty-six AD patients were divided into three dose cohorts; each dose cohort consisted of twelve patients with 8 patients randomized to AIT-082 and 4 to placebo. The 3 doses of AIT-082 evaluated in this study were 100 mg/day, 500 mg/day, and 2,000 mg/day. There were no serious adverse events at any dose and the drug was well tolerated without significant side effects. AIT-082 was orally and rapidly absorbed, resulting in peak serum concentrations within 2 hours with an elimination half-life of approximately 20 hours. Higher doses resulted in corresponding increases in peak concentrations and areas under the curve (AUC). There was an approximate 2-fold accumulation in AIT-082 with daily dosing (as reflected by the AUC) at steady state. There were no significant differences by treatment arm on the clinical or neuropsychological evaluations. AIT-082 was rapidly absorbed by the oral route with a half-life suitable for dosing once or twice daily. No problems with tolerability or safety were found. AIT-082 appears suitable for testing in larger clinical trials for the treatment of AD and other neurologic disorders.

Doody RS, Dunn JK, Clark CM, Farlow M, Foster NL, Liao T, Gonzales N, Lai E, Massman P. · Baylor College of Medicine Alzheimer's Disease Research Center (AGO-8664), Houston, Tex 77030-3498, USA. · Dement Geriatr Cogn Disord. · Pubmed #11351141 No free full text.

Abstract: OBJECTIVE: To compare rates of cognitive decline between probable Alzheimer's disease (AD) patients treated with long-duration cholinesterase inhibitors (ChE-Is) and those who remained untreated. BACKGROUND: ChE-Is, including donepezil and tracrine, have shown beneficial effects on cognition and global functioning in patients with AD. The duration of these benefits is unknown because the longest double-blind placebo-controlled studies reported were only approximately 6 months long. Ethical concerns regarding randomization of patients to placebo for long periods make it difficult to undertake trials of longer duration. METHODS: We identified patients in 4 AD centers who were or were not consistently treated with ChE-Is and who had demographic, psychometric and follow-up data. We compared 205 ChE-I-treated and 218 untreated AD patients on baseline variables hypothesized to differ between these groups, on baseline Mini Mental Status Examination (MMSE) scores and on rates of MMSE change at 1 year. The analysis was performed initially with all ChE-I-treated patients as a single group versus untreated subjects, and then with donepezil versus untreated subjects and tacrine versus untreated subjects. RESULTS: As expected, treated and untreated patients differed with respect to age, education, ethnicity, percentage of community dwelling and exact days of follow-up (ANOVA and chi2) in several comparisons, but did not differ on baseline MMSE score. These baseline variables were highly intercorrelated. MMSE scores declined significantly more slowly after 1 year of ChE-I treatment compared to untreated patients (p = 0.05) after controlling for baseline differences in age, education, ethnicity and percentage of community dwelling. Slowing of decline was significant in the donepezil-treated patients (p = 0.007) but not in the tacrine-treated group (p = 0.33). CONCLUSIONS: This study, utilizing concurrent, nonrandomized controls, suggests that donepezil continues to have efficacy over at least the first year of therapy. Other studies are needed to determine whether the benefits are maintained beyond 1 year.

Farlow M, Anand R, Messina J, Hartman R, Veach J. · Department of Neurology, Indiana University School of Medicine, Indianapolis, IN 46202-5111, USA. · Eur Neurol. · Pubmed #11096224 No free full text.

Abstract: The efficacy of a centrally active cholinesterase inhibitor, rivastigmine tartrate (ENA 713; Exelon, in patients with mild to moderately severe Alzheimer's disease was evaluated in a 26-week open-label extension of a 26-week, double-blind, placebo-controlled study. By 52 weeks, patients originally treated with 6-12 mg/day rivastigmine had significantly better cognitive function than patients originally treated with placebo.

Campbell N, Ayub A, Boustani MA, Fox C, Farlow M, Maidment I, Howards R. · Wishard Health Services, Indianapolis, Indiana, USA. · Clin Interv Aging. · Pubmed #19281064 links to  free full text

Abstract: OBJECTIVE: To determine the efficacy of cholinesterase inhibitors (ChEIs) in improving the behavioral and psychological symptoms of dementia (BPSD) in patients with Alzheimer's disease (AD). DATA SOURCES: We searched MEDLINE, Cochrane Registry, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) from 1966 to 2007. We limited our search to English Language, full text, published articles and human studies. DATA EXTRACTION: We included randomized, double-blind, placebo-controlled trials evaluating the efficacy of donepezil, rivastigmine, or galantamine in managing BPSD displayed by AD patients. Using the United States Preventive Services Task Force (USPSTF) guidelines, we critically appraised all studies and included only those with an attrition rate of less than 40%, concealed measurement of the outcomes, and intention to treat analysis of the collected data. All data were imputed into pre-defined evidence based tables and were pooled using the Review Manager 4.2.1 software for data synthesis. RESULTS: We found 12 studies that met our inclusion criteria but only nine of them provided sufficient data for the meta-analysis. Among patients with mild to severe AD and in comparison to placebo, ChEIs as a class had a beneficial effects on reducing BPSD with a standard mean difference (SMD) of -0.10 (95% confidence interval [CI]; -0.18, -0.01) and a weighted mean difference (WMD) of-1.38 neuropsychiatry inventory point (95% CI; -2.30, -0.46). In studies with mild AD patients, the WMD was -1.92 (95% CI; -3.18, -0.66); and in studies with severe AD patients, the WMD was -0.06 (95% CI; -2.12, +0.57). CONCLUSION: Cholinesterase inhibitors lead to a statistical significant reduction in BPSD among patients with AD, yet the clinical relevance of this effect remains unclear.

Winblad B, Grossberg G, Frölich L, Farlow M, Zechner S, Nagel J, Lane R. · Karolinska Institutet Alzheimer Research Center, Stockholm, Sweden. · Neurology. · Pubmed #17646619 No free full text.

Abstract: The rivastigmine patch is the first transdermal treatment for Alzheimer disease (AD). By providing continuous delivery of drug into the bloodstream over 24 hours, transdermal delivery may offer benefits superior to those of oral administration. This study compared the efficacy, safety and tolerability of rivastigmine patches with capsules and placebo. IDEAL (Investigation of transDermal Exelon in ALzheimer's disease) was a 24-week, double-blind, double-dummy, placebo- and active-controlled study. Patients with AD were randomized to placebo or one of three active treatment target dose groups: 10-cm(2) rivastigmine patch (delivering 9.5 mg/24 hours); 20-cm(2) rivastigmine patch (17.4 mg/24 hours); or 6-mg BID rivastigmine capsules. Primary efficacy measures were the Alzheimer's Disease Assessment Scale-Cognitive subscale and Alzheimer's Disease Cooperative Study-Clinical Global Impression of Change. Secondary outcome measures assessed a range of domains, including behavior, cognitive performance, attention, executive functions, and activities of daily living. A total of 1,195 AD patients participated. All rivastigmine treatment groups showed significant improvement relative to placebo. The 10-cm(2) patch showed similar efficacy to capsules, with approximately two-thirds fewer reports of nausea (7.2% vs 23.1%) and vomiting (6.2% vs 17.0%), incidences statistically not significantly different from placebo (5.0% and 3.3% for nausea and vomiting, respectively). The 20-cm(2) patch showed earlier improvement and numerically superior cognitive scores vs the 10-cm(2) patch with similar tolerability to capsules. Local skin tolerability was good. The transdermal patch with rivastigmine may offer additional therapeutic benefits and may prove to be the best delivery system for this drug to treat AD.

Wei X, Chen X, Fontanilla C, Zhao L, Liang Z, Dodel R, Hampel H, Farlow M, Du Y. · Department of Neurology, Indiana University School of Medicine, 975 West Walnut Street, IB457, Indianapolis, IN 46202, USA. · Life Sci. · Pubmed #17257626 links to  free full text

Abstract: Recently, association of an interleukin-1A promoter polymorphism (-889, thymine/thymine (T/T)) with Alzheimer's disease was reported, suggesting that this cytokine may play an important role in disease development. To understand the mechanism underlying the interleukin-1A promoter's role in Alzheimer's disease, a study comparing promoter function of an interleukin-1A polymorphism was performed in the SVG astroglia cell line. The effects of thymine and cytosine on transcriptional activity of the interleukin-1A promoter were analyzed by testing luciferase-reporter activity in transfected SVG cells. Our results demonstrate that cytosine/thymine conversion increases activity of the interleukin-1A promoter in SVG cells. Both sodium salicylate and lovastatin are able to block induced promoter activities in astroglial cells. Induced promoter activity by the polymorphism (T/T) may result in the upregulation of interleukin-1alpha protein and "cytokine cycle" amplification, which may promote disease development.

Spillantini MG, Murrell JR, Goedert M, Farlow M, Klug A, Ghetti B. · Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Robinson Way, Cambridge CB2 2PY, UK. · J Alzheimers Dis. · Pubmed #16914875 No free full text.

Abstract: Work in 1980s and early 1990s established that the microtubule-associated protein tau is the major component of the paired helical filament of Alzheimer's disease. Similar filamentous deposits are also present in a number of other diseases, including progressive supranuclear palsy, corticobasal degeneration and Pick's disease. In 1998, the relevance of tau dysfunction for the neurodegenerative process became clear, when mutations in the tau gene were found to cause the inherited "frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17)". The paper highlighted here [Spillantini M.G., Murrell J.R., Goedert M., Farlow M., Klug A. and Ghetti B. (1998) Mutation in the tau gene in familial multiple system tauopathy with presenile dementia. Proc. Natl. Acad. Sci. USA 95, 7737-7741] reported a mutation at position + 3 in the intron following alternatively spliced exon 10 of the tau gene in a family.

Farlow M, Lane R, Kudaravalli S, He Y. · Department of Neurology, Indiana University School of Medicine, Indianapolis, IN, USA. · Pharmacogenomics J. · Pubmed #15289797 No free full text.

Abstract: This retrospective analysis of two double-blind, placebo-controlled studies in patients with mild to moderately severe AD investigated the efficacy of rivastigmine 6-12 mg/day on cognitive outcomes in patients with or without the apolipoprotein (APOE) epsilon4 allele. APOE data were collected from patients who consented to pharmacogenetic testing. Treatment differences within each subgroup were compared, using the Observed Case (OC) population. The APOE epsilon4 and non-APOE epsilon4 subgroups comprised 246 and 121 patients, respectively. Overall, APOE epsilon4 noncarriers showed greater decline than carriers (P<0.05). However, at 26 weeks, placebo-treated APOE epsilon4 patients declined 3.04 points below baseline on the cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-cog), and rivastigmine-treated patients improved by 1.67 points. Non-APOE epsilon4 placebo-treated patients declined by 4.59 points and rivastigmine-treated patients declined by 0.48 points. Thus, non-APOE epsilon4 carriers showed a less favorable course under either placebo or rivastigmine, but both genotype-defined subgroups showed quantitatively similar responses to therapy (both P<0.05 vs placebo).

Lahiri DK, Chen D, Ge YW, Farlow M, Kotwal G, Kanthasamy A, Ingram DK, Greig NH. · Department of Psychiatry, Institute of Psychiatric Research, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA. · Ann N Y Acad Sci. · Pubmed #15033804 No free full text.

Abstract: Oxidative stress is a risk factor for Alzheimer's disease (AD) whose major hallmark includes brain depositions of the amyloid beta peptide (Abeta) derived from the beta-amyloid precursor protein (APP). Our aim was to determine whether or not excessive Abeta deposition would alter nitric oxide synthase (NOS) activity, and thereby affect NOS-mediated superoxide formation. We compared NOS activity in brain extracts between Tg mice (expressing APP Swedish double mutation plus presenilin [PS-1] and nontransgenic [nTg] mice. Five brain regions, including cerebral cortex, hippocampus, cerebellum, and striatum from both nTg and Tg mice showed a detectable level of neuronal (n) NOS activity. Cerebellar extracts from both nTg and Tg mice displayed the highest level of nNOS activity, which was fourfold higher than cortical extracts. Although there was an increase in nNOS activity in Tg brain extracts, this did not attain statistical significance. A similar result was obtained for inducible NOS levels. Our results suggest that excess levels of Abeta failed to both trigger NOS activity and change NOS levels.

Hampel H, Teipel SJ, Fuchsberger T, Andreasen N, Wiltfang J, Otto M, Shen Y, Dodel R, Du Y, Farlow M, Möller HJ, Blennow K, Buerger K. · Department of Psychiatry, Alzheimer Memorial Center and Geriatric Psychiatry Branch, Dementia Research Section and Memory Clinic, Ludwig-Maximilian University, Nussbaumstrasse 7, 80336 Munich, Germany. · Mol Psychiatry. · Pubmed #14699432 No free full text.

Abstract: Subjects with mild cognitive impairment (MCI) are at a high risk of developing clinical Alzheimer's disease (AD). We asked to what extent the core biomarker candidates cerebro-spinal fluid (CSF) beta-amyloid(1-42) (Abeta(1-42)) and CSF tau protein concentrations predict conversion from MCI to AD. We studied 52 patients with MCI, 93 AD patients, and 10 healthy controls (HC). The MCI group was composed of 29 patients who had converted to AD during follow-up, and of 23 patients who showed no cognitive decline. CSF Abeta(1-42) and tau protein levels were assessed at baseline in all subjects, using enzyme-linked immunosorbent assays. For assessment of sensitivity and specificity, we used independently established reference values for CSF Abeta(1-42) and CSF tau. The levels of CSF tau were increased, whereas levels of Abeta(1-42) were decreased in MCI subjects. Abeta(1-42) predicted AD in converted MCI with a sensitivity of 59% and a specificity of 100% compared to HC. Tau yielded a greater sensitivity of 83% and a specificity of 90%. In a multiple Cox regression analysis within the MCI group, low baseline levels of Abeta(1-42), but not other predictor variables (tau protein, gender, age, apolipoprotein E epsilon4 carrier status, Mini Mental Status Examination score, observation time, antidementia therapy), correlated with conversion status (P<0.05). Our findings support the notion that CSF tau and Abeta(1-42) may be useful biomarkers in the early identification of AD in MCI subjects.

Clark CM, Xie S, Chittams J, Ewbank D, Peskind E, Galasko D, Morris JC, McKeel DW, Farlow M, Weitlauf SL, Quinn J, Kaye J, Knopman D, Arai H, Doody RS, DeCarli C, Leight S, Lee VM, Trojanowski JQ. · Departments of Neurology, Center for Neuerodegenerative Disease Research, alzheimer's Disease Center, Philadelphia, PA 19104, USA. · Arch Neurol. · Pubmed #14676043 links to  free full text

Abstract: BACKGROUND: Tau and beta-amyloid (Abeta) are proposed diagnostic biomarkers for Alzheimer disease (AD). Previous studies report their relationship to clinical diagnoses of AD and other dementias. To understand their value as predictors of disease-specific pathology, levels determined during life must be correlated with definitive diagnoses in mixed dementia groups and cognitively normal subjects. OBJECTIVES: To correlate antemortem cerebrospinal fluid (CSF) tau and Abeta levels with definitive dementia diagnosis in a diverse group of patients; to calculate statistics for CSF tau and Abeta. DESIGN: Prospective study. SETTING: Ten clinics experienced in the diagnosis of neurodegenerative dementias.Patients One hundred six patients with dementia and 4 cognitively normal subjects with a definitive diagnosis, and 69 clinically diagnosed cognitively normal subjects. MAIN OUTCOME MEASURES: Correlation of CSF tau and Abeta with final diagnosis. RESULTS: Mean tau level was 612 pg/mL for the 74 patients with AD, 272 pg/mL for 10 patients with frontal dementia, 282 pg/mL for 3 patients with dementia with Lewy bodies, and 140 pg/mL for 73 cognitively normal control subjects. Tau was less than 334 pg/mL for 20 patients with AD. Abeta42 was reduced in patients with AD (61 fmol/mL) compared with patients with frontal dementia (133 fmol/mL) and control subjects (109 fmol/mL), but not compared with patients with dementia with Lewy bodies (14 fmol/mL) or prion disease (60 fmol/mL). CONCLUSIONS: Elevated CSF tau levels are associated with AD pathology and can help discriminate AD from other dementing disorders. However, some patients with AD have a level less than the mean +/- 2 SDs of the cognitively normal cohort.

DeKosky ST, Ikonomovic MD, Wang X, Farlow M, Wisniewski S, Lopez OL, Becker JT, Saxton J, Klunk WE, Sweet R, Kaufer DI, Kamboh MI. · Department of Neurology and the Alzheimer's Disease Research Center, University of Pittsburgh, PA, USA. · Ann Neurol. · Pubmed #12509851 No free full text.

Abstract: alpha-1-Antichymotrypsin (ACT) is present in neuritic plaques in which it participates in the inflammatory cascade of Alzheimer's disease (AD). Reports of blood ACT levels in AD, and its usefulness as a disease biomarker, have been conflicting. In an effort to clarify this, we measured plasma ACT levels in 516 white subjects including 359 subjects with probable or possible AD, 44 subjects with other late-life dementias, and 113 nondemented people. Subjects with systemic inflammatory diseases or who were taking antiinflammatory medications were excluded. All patients underwent extensive medical and detailed neuropsychological examinations at the time their blood was drawn. We found that plasma ACT levels were elevated in AD patients compared with the control group (p = 0.01) and were associated with severity of AD dementia; there was a negative association with the Mattis Dementia Rating Scale (a global measure of cognition) and a positive association with the Clinical Dementia Rating Scale (a global functional assessment). These relationships remained significant after controlling for demographic and genetic variables. When AD subjects were stratified into subgroups by dementia severity, matched by age, education, and gender, increased serum ACT correlated with Clinical Dementia Rating Scale (p = 0.0041) or Mattis Dementia Rating Scale (p = 0.0031) scores. ACT measurements in cerebrospinal fluid from an additional 34 AD cases and 16 controls showed elevated levels (p = 0.02) in AD. There was a negative correlation (p = 0.037) between cerebrospinal fluid ACT levels and clinical severity as measured by the Mini-Mental State Examination. Our results demonstrate that peripheral ACT levels are elevated in AD, but not in dementias other than AD, and they increase with progression of AD dementia. Although not useful as a diagnostic biomarker, ACT may reflect disease severity and may be helpful as a within subject biomarker in interventions (particularly with antiinflammatory agents) directed at slowing or halting progression of disease.

Wilkinson DG, Hock C, Farlow M, van Baelen B, Schwalen S. · Memory Assessment and Research Centre, Moorgreen Hospital, Southampton, UK · Int J Clin Pract. · Pubmed #12296613 No free full text.

Abstract: We investigated whether galantamine (Reminyl), a cholinergic agent with a dual mode of action for the treatment of mild to moderate Alzheimer's disease (AD), would benefit patients with more advanced illness. We performed a post hoc analysis on pooled data from four pivotal studies in patients with 'advanced moderate' AD: baseline Mini-Mental State Evaluation (MMSE) scores < or = 12 (range 10-12; mean MMSE score 11) or Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog) scores >30 (range 31-69; mean ADAS-cog score 39). Over 5-6 months, cognitive abilities were improved with galantamine versus placebo (p<0.001; mean treatment difference 6.5 points). At 6 months, galantamine benefited functional abilities (p<0.001 vs placebo). The first quartile of galantamine patients improved over baseline by 10.5 ADAS-cog points. Cognitive and functional abilities were maintained around baseline; behavioural symptoms were delayed. Over 6 months, galantamine provided a broad spectrum of benefits to patients with 'advanced moderate' AD.

Dodel R, Hampel H, Depboylu C, Lin S, Gao F, Schock S, Jäckel S, Wei X, Buerger K, Höft C, Hemmer B, Möller HJ, Farlow M, Oertel WH, Sommer N, Du Y. · Department of Neurology, Philipps University Marburg, Germany. · Ann Neurol. · Pubmed #12210803 No free full text.

Abstract: Naturally occurring antibodies directed against beta-amyloid (Abeta) were detected in intravenous immunoglobulin preparations. After intravenous immunoglobulin treatment in patients with different neurological diseases, total Abeta and Abeta(1-42) in the cerebrospinal fluid was reduced significantly compared with baseline values. In the serum, total Abeta levels increased after intravenous immunoglobulin treatment, whereas no significant change was observed in Abeta(1-42) levels. Antibodies against Abeta were found to be increased in the serum and cerebrospinal fluid after intravenous immunoglobulin treatment. This study provides evidence that intravenous immunoglobulin or purified Abeta antibodies may modify Abeta and Abeta(1-42) levels, suggesting potential utility as a therapy for Alzheimer disease.

Dodel RC, Du Y, Depboylu C, Kurz A, Eastwood B, Farlow M, Oertel WH, Müller U, Riemenschneider M. · Department of Neurology, Philipps-University Marburg, Germany. · Neurology. · Pubmed #11865157 No free full text.

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Du Y, Dodel R, Hampel H, Buerger K, Lin S, Eastwood B, Bales K, Gao F, Moeller HJ, Oertel W, Farlow M, Paul S. · Department of Pharmacology, Indiana University School of Medicine, Indianapolis 46285, USA. · Neurology. · Pubmed #11552007 No free full text.

Abstract: OBJECTIVE: To investigate whether it was possible to detect the presence and different levels of naturally occurring anti-beta-amyloid (Abeta) antibodies in the CSF of patients with AD and age-matched controls by employing a sensitive ELISA. BACKGROUND: Immunization with preaggregated amyloid beta-peptide (Abeta(1-42)) and administration of antibodies against Abeta into amyloid precursor protein APP(V717F)- transgenic mice (an animal model of AD) have recently been reported to dramatically reduce amyloid plaque deposition, neuritic dystrophy, and astrogliosis, most likely by enhancing Abeta clearance from brain. METHODS: A sensitive ELISA was performed to detect levels of naturally occurring anti-Abeta antibodies in the CSF of patients with AD and age-matched controls. Additionally, an immunoprecipitation assay was performed to confirm that naturally occurring anti-Abeta antibodies also exist in the human blood. RESULT: - Naturally occurring antibodies directed against Abeta were found in the CSF and plasma of patients with AD and healthy control subjects. Moreover, CSF anti-Abeta antibody titers are significantly lower in patients with AD compared with healthy control subjects. CONCLUSION: Naturally occurring antibodies directed against Abeta exist in human CSF and plasma. The CSF anti-Abeta antibody titers may be helpful in better understanding the effects of future immunologic therapies for AD.