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INTRODUCTION: This clinical trial evaluates the efficacy and safety of a 6-week course of daily neuroAD™ therapy. METHODS: 131 subjects between 60 and 90 years old, unmedicated for Alzheimer's disease (AD), or on stable doses of an acetylcholinesterase inhibitor and/or memantine, with Mini-Mental State Examination scores between 18 and 26, clinical dementia rating scale scores of 1 or 2, enrolled for a prospective, randomized, double-blind, sham-controlled, multicenter clinical trial. Structural brain MRIs were obtained for transcranial magnetic stimulation targeting. Baseline Alzheimer's disease assessment scale-cognitive (ADAS-Cog) and Clinical Global Impression of Change were assessed. 129 participants were randomized to active treatment plus standard of care (SOC) or sham treatments plus SOC. RESULTS: Subjects with baseline ADAS-Cog ≤ 30 (~85% of study population) showed a statistically significant benefit favoring active over sham. Responder analysis showed 31.7% participants in the active group with ≤ -4 point improvement on ADAS-Cog versus 15.4% in the sham group. DISCUSSION: neuroAD™ Therapy System provides a low-risk therapeutic benefit for patients with milder AD (baseline ADAS-Cog ≤30) beyond pharmacologic SOC.
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Enfermedad de Alzheimer/terapia , Estimulación Magnética Transcraneal/instrumentación , Anciano , Anciano de 80 o más Años , Inhibidores de la Colinesterasa/uso terapéutico , Método Doble Ciego , Femenino , Humanos , Masculino , Memantina/uso terapéutico , Escala del Estado Mental , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
Importance: Patients with amnestic mild cognitive impairment (aMCI) may progress to clinical Alzheimer disease (AD), remain stable, or revert to normal. Earlier progression to AD among patients who were ß-amyloid positive vs those who were ß-amyloid negative has been previously observed. Current research now accepts that a combination of biomarkers could provide greater refinement in the assessment of risk for clinical progression. Objective: To evaluate the ability of flutemetamol F 18 and other biomarkers to assess the risk of progression from aMCI to probable AD. Design, Setting, and Participants: In this multicenter cohort study, from November 11, 2009, to January 16, 2014, patients with aMCI underwent positron emission tomography (PET) at baseline followed by local clinical assessments every 6 months for up to 3 years. Patients with aMCI (365 screened; 232 were eligible) were recruited from 28 clinical centers in Europe and the United States. Physicians remained strictly blinded to the results of PET, and the standard of truth was an independent clinical adjudication committee that confirmed or refuted local assessments. Flutemetamol F 18-labeled PET scans were read centrally as either negative or positive by 5 blinded readers with no knowledge of clinical status. Statistical analysis was conducted from February 19, 2014, to January 26, 2018. Interventions: Flutemetamol F 18-labeled PET at baseline followed by up to 6 clinical visits every 6 months, as well as magnetic resonance imaging and multiple cognitive measures. Main Outcomes and Measures: Time from PET to probable AD or last follow-up was plotted as a Kaplan-Meier survival curve; PET scan results, age, hippocampal volume, and aMCI stage were entered into Cox proportional hazards logistic regression analyses to identify variables associated with progression to probable AD. Results: Of 232 patients with aMCI (118 women and 114 men; mean [SD] age, 71.1 [8.6] years), 98 (42.2%) had positive results detected on PET scan. By 36 months, the rates of progression to probable AD were 36.2% overall (81 of 224 patients), 53.6% (52 of 97) for patients with positive results detected on PET scan, and 22.8% (29 of 127) for patients with negative results detected on PET scan. Hazard ratios for association with progression were 2.51 (95% CI, 1.57-3.99; P < .001) for a positive ß-amyloid scan alone (primary outcome measure), 5.60 (95% CI, 3.14-9.98; P < .001) with additional low hippocampal volume, and 8.45 (95% CI, 4.40-16.24; P < .001) when poorer cognitive status was added to the model. Conclusions and Relevance: A combination of positive results of flutemetamol F 18-labeled PET, low hippocampal volume, and cognitive status corresponded with a high probability of risk of progression from aMCI to probable AD within 36 months.
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Enfermedad de Alzheimer/diagnóstico por imagen , Amnesia/diagnóstico por imagen , Encéfalo/efectos de los fármacos , Disfunción Cognitiva/diagnóstico por imagen , Progresión de la Enfermedad , Tomografía de Emisión de Positrones/métodos , Anciano , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/metabolismo , Amnesia/complicaciones , Amnesia/metabolismo , Péptidos beta-Amiloides/metabolismo , Compuestos de Anilina , Benzotiazoles , Biomarcadores , Encéfalo/metabolismo , Disfunción Cognitiva/complicaciones , Disfunción Cognitiva/metabolismo , Femenino , Humanos , Masculino , Factores de RiesgoRESUMEN
AIMS: To evaluate the impact of amyloid PET imaging on diagnosis and patient management in a multicenter, randomized, controlled study. METHODS: Physicians identified patients seeking a diagnosis for mild cognitive impairment or dementia, possibly due to Alzheimer disease (AD), and recorded a working diagnosis and a management plan. The patients underwent florbetapir PET scanning and were randomized to either immediate or delayed (1-year) feedback regarding amyloid status. At the 3-month visit, the physician updated the diagnosis and recorded a summary of the actual patient management since the post-scan visit. The study examined the impact of immediate versus delayed feedback on patient diagnosis/management at 3 and 12 months. RESULTS: A total of 618 subjects were randomized (1:1) to immediate or delayed feedback arms, and 602 subjects completed the 3-month primary endpoint visit. A higher proportion of patients in the immediate feedback arm showed a change in diagnosis compared to the controls (32.6 vs. 6.4%; p = 0.0001). Similarly, a higher proportion of patients receiving immediate feedback had a change in management plan (68 vs. 55.5%; p < 0.002), mainly driven by changes in AD medication. Specifically, acetylcholinesterase inhibitors were prescribed to 67% of the amyloid-positive and 27% of the amyloid-negative subjects in the information group compared with 56 and 43%, respectively, in the control group (p < 0.0001). These between-group differences persisted until the 12-month visit. CONCLUSION: Knowledge of the amyloid status affects the diagnosis and alters patient management.
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Enfermedad de Alzheimer/diagnóstico por imagen , Compuestos de Anilina , Disfunción Cognitiva/diagnóstico por imagen , Glicoles de Etileno , Placa Amiloide/metabolismo , Tomografía de Emisión de Positrones/métodos , Anciano , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/psicología , Amiloide/metabolismo , Proteínas Amiloidogénicas/metabolismo , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/psicología , Retroalimentación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
INTRODUCTION: Performance of the amyloid tracer [18F]flutemetamol was evaluated against three pathology standard of truth (SoT) measures including neuritic plaques (CERAD "original" and "modified" and the amyloid component of the 2012 NIA-AA guidelines). METHODS: After [18F]flutemetamol imaging, 106 end-of-life patients who died underwent postmortem brain examination for amyloid plaque load. Blinded positron emission tomography scan interpretations by five independent electronically trained readers were compared with pathology measures. RESULTS: By SoT, sensitivity and specificity of majority image interpretations were, respectively, 91.9% and 87.5% with "original CERAD," 90.8% and 90.0% with "modified CERAD," and 85.7% and 100% with the 2012 NIA-AA criteria. DISCUSSION: The high accuracy of either CERAD criteria suggests that [18F]flutemetamol predominantly reflects neuritic amyloid plaque density. However, the use of CERAD criteria as the SoT can result in some false-positive results because of the presence of diffuse plaques, which are accounted for when the positron emission tomography read is compared with the 2012 NIA-AA criteria.
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OBJECTIVES: Long-term safety and tolerability of ACC-001 (vanutide cridificar), an antiamyloid- beta therapeutic vaccine, was evaluated in subjects with mild to moderate Alzheimer's disease. DESIGN: Phase 2a extension studies of randomized parent trials were conducted in the United States, European Union, and Japan. METHODS: Four immunizations of ACC-001 were administered at the same 3 dose levels (3, 10, and 30 µg) to subjects randomized in the parent studies; ACC-001 was administered with QS-21 adjuvant. Safety, tolerability, and immunogenicity were assessed during active treatment and 6-month follow-up. RESULTS: ACC-001 + QS-21 was well tolerated in the United States (N=110) and European Union (N=50), and Japan (N=53) extension studies; safety profile was similar to that observed in the parent studies, and no new safety signals were identified. Overall, injection site reactions were the most common adverse event in these studies. Anti-amyloid antibody titers were elicited in all groups, with the highest titers observed in subjects who received ACC-001 + QS-21 in both the parent and extension studies. CONCLUSIONS: Long-term exposure to ACC-001 + QS-21 was well tolerated in subjects with Alzheimer's disease, suggesting that side effects do not pose a principal limitation for anti-amyloid active immunotherapy. The highest anti-amyloid-beta IgG titers are elicited during long-term therapy with ACC-001 + QS-21 compared with other regimens.
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Enfermedad de Alzheimer/inmunología , Enfermedad de Alzheimer/terapia , Proteínas Recombinantes de Fusión/uso terapéutico , Saponinas/uso terapéutico , Vacunación/métodos , Anciano , Anciano de 80 o más Años , Péptidos beta-Amiloides/inmunología , Relación Dosis-Respuesta Inmunológica , Europa (Continente) , Femenino , Humanos , Cooperación Internacional , Japón , Estudios Longitudinales , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Resultado del Tratamiento , Estados UnidosRESUMEN
Vanutide cridificar (ACC-001), an immunotherapeutic vaccine, is a potentially disease-modifying therapy that aims to reduce brain amyloid-ß (Aß) plaques in patients with Alzheimer's disease (AD). ACC-001 was evaluated in two phase 2a, multicenter, randomized, third party-unblinded, placebo-controlled, multiple ascending-dose studies of ACC-001 (3µg, 10µg, 30µg) with and without QS-21 adjuvant that enrolled patients with mild-to-moderate AD (nâ=â245). Patients were treated with up to five doses of study vaccine or placebo and followed for safety and tolerability (primary objective) and anti-Aß IgG immunogenicity (secondary objective) up to 12 months after the last vaccination. Exploratory assessments included cognitive/functional measures, brain magnetic resonance imaging (MRI) volumetry, and pharmacodynamic markers in plasma and cerebrospinal fluid (CSF). The most frequent treatment-emergent adverse events (≥10%) were local injection reactions and headache. Amyloid-related imaging abnormalities with vasogenic edema occurred in two (0.8%) patients (ACC-001 30µg + QS-21; ACC-001 10µg). ACC-001 + QS-21 elicited consistently higher peak and sustained anti-Aß IgG titers compared with ACC-001 alone. Plasma Aßx-40 was significantly higher in all ACC-001 + QS-21 groups versus placebo (weeks 16-56), with no evidence of dose response. Exploratory cognitive evaluations, volumetric brain MRI, and CSF biomarkers did not show differences or trends between treatment groups and placebo. ACC-001 with or without QS-21 adjuvant has an acceptable safety profile in patients with mild-to-moderate AD.
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Adyuvantes Inmunológicos/uso terapéutico , Enfermedad de Alzheimer/tratamiento farmacológico , Antipsicóticos/uso terapéutico , Proteínas Recombinantes de Fusión/uso terapéutico , Saponinas/uso terapéutico , Anciano , Enfermedad de Alzheimer/diagnóstico por imagen , Péptidos beta-Amiloides/sangre , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Humanos , Interferón gamma/sangre , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Fragmentos de Péptidos/sangre , Método Simple Ciego , Resultado del TratamientoRESUMEN
ABT-089, an α4ß2 neuronal nicotinic receptor partial agonist, was evaluated for efficacy and safety in mild to moderate Alzheimer disease patients receiving stable doses of acetylcholinesterase inhibitors. This phase 2 double-blind, placebo-controlled, proof-of-concept, and dose-finding study adaptively randomized patients to receive ABT-089 (5, 10, 15, 20, 30, or 35 mg once daily) or placebo for 12 weeks. The primary efficacy endpoint was the Alzheimer's Disease Assessment Scale, cognition subscale (ADAS-Cog) total score. A Bayesian response-adaptive randomization algorithm dynamically assigned allocation probabilities based on interim ADAS-Cog total scores. A normal dynamic linear model for dose-response relationships and a longitudinal model for predicting final ADAS-cog score were employed in the algorithm. Stopping criteria for futility or success were defined. The futility stopping criterion was met, terminating the study with 337 patients randomized. No dose-response relationship was observed and no dose demonstrated statistically significant improvement over placebo on ADAS-Cog or any secondary endpoint. ABT-089 was well tolerated at all dose levels. When administered as adjunctive therapy to acetylcholinesterase inhibitors, ABT-089 was not efficacious in mild to moderate Alzheimer disease. The adaptive study design enabled the examination of a broad dose range, enabled rapid determination of futility, and reduced patient exposure to nonefficacious doses of the investigational compound.
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Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/uso terapéutico , Cognición/efectos de los fármacos , Piridinas/uso terapéutico , Pirrolidinas/uso terapéutico , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico , Teorema de Bayes , Inhibidores de la Colinesterasa/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Piridinas/administración & dosificación , Pirrolidinas/administración & dosificación , Resultado del TratamientoRESUMEN
AIMS: To identify factors predicting improvement/stabilization on the Alzheimer's Disease Cooperative Study-Clinical Global Impression of Change (ADCS-CGIC) and investigate whether early treatment responses can predict long-term outcomes, during a trial of 13.3 mg/24 h versus 4.6 mg/24 h rivastigmine patch in patients with severe Alzheimer's disease (AD). METHODS: Logistic regression was used to relate Week 24 ADCS-CGIC score to potential baseline predictors. Additional analyses based on receiver-operating characteristic curves were performed using Week 8/16 ADCS-CGIC scores to predict response (13.3 mg/24 h patch) at Week 24. ADCS-CGIC score of (1) 1-3 = "improvement," (2) 1-4 = "improvement or no change". RESULTS: "Treatment" (13.3 mg/24 h patch) and increased age were significant predictors of "improvement" (P = 0.01 and P = 0.003, respectively), and "treatment" (P = 0.001), increased age (P = 0.002), and prior AD treatment (P = 0.03) for "improvement or no change". At Week 8 and 16, ADCS-CGIC scores of 4 and 5 were optimal thresholds in predicting "improvement," and "improvement or no change," respectively, at Week 24. CONCLUSIONS: A significant therapeutic effect of high-dose rivastigmine patch on ADCS-CGIC response was observed. The 13.3 mg/24 h patch was identified as a predictor of "improvement" or "improvement or no change". Patients with minimal worsening/improvement/no change after treatment initiation may be more likely to respond following long-term therapy.
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Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/uso terapéutico , Rivastigmina/uso terapéutico , Resultado del Tratamiento , Anciano , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Humanos , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Curva ROCRESUMEN
IMPORTANCE: In vivo imaging of brain ß-amyloid, a hallmark of Alzheimer disease, may assist in the clinical assessment of suspected Alzheimer disease. OBJECTIVE: To determine the sensitivity and specificity of positron emission tomography imaging with flutemetamol injection labeled with radioactive fluorine 18 to detect ß-amyloid in the brain using neuropathologically determined neuritic plaque levels as the standard of truth. DESIGN, SETTING, AND PARTICIPANTS: Open-label multicenter imaging study that took place at dementia clinics, memory centers, and hospice centers in the United States and England from June 22, 2010, to November 23, 2011. Participants included terminally ill patients who were 55 years or older with a life expectancy of less than 1 year. INTERVENTIONS: Flutemetamol injection labeled with radioactive fluorine 18 (Vizamyl; GE Healthcare) administration followed by positron emission tomography imaging and subsequent brain donation. MAIN OUTCOMES AND MEASURES: Sensitivity and specificity of flutemetamol injection labeled with radioactive fluorine 18 positron emission tomography imaging for brain ß-amyloid. Images were reviewed without and with computed tomography scans and classified as positive or negative for ß-amyloid by 5 readers who were blind to patient information. In patients who died, neuropathologically determined neuritic plaque levels were used to confirm scan interpretations and determine sensitivity and specificity. RESULTS: Of 176 patients with evaluable images, 68 patients (38%) died during the study, were autopsied, and had neuritic plaque levels determined; 25 brains (37%) were ß-amyloid negative; and 43 brains (63%) were ß-amyloid positive. Imaging was performed a mean of 3.5 months (range, 0 to 13 months) before death. Sensitivity without computed tomography was 81% to 93% (median, 88%). Median specificity was 88%, with 4 of 5 of the readers having specificity greater than 80%. When scans were interpreted with computed tomography images, sensitivity and specificity improved for most readers but the differences were not significant. The area under the receiver operating curve was 0.90. There were no clinically meaningful findings in safety parameters. CONCLUSIONS AND RELEVANCE: This study showed that flutemetamol injection labeled with radioactive fluorine 18 was safe and had high sensitivity and specificity in an end-of-life population. In vivo detection of brain ß-amyloid plaque density may increase diagnostic accuracy in cognitively impaired patients.
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Compuestos de Anilina , Benzotiazoles , Radioisótopos de Flúor , Placa Amiloide/diagnóstico por imagen , Placa Amiloide/epidemiología , Tomografía de Emisión de Positrones/normas , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Placa Amiloide/psicología , Método Simple CiegoRESUMEN
INTRODUCTION: We investigated whether event-related potentials (ERP) collected in outpatient settings and analyzed with standardized methods can provide a sensitive and reliable measure of the cognitive deficits associated with early Alzheimer's disease (AD). METHODS: A total of 103 subjects with probable mild AD and 101 healthy controls were recruited at seven clinical study sites. Subjects were tested using an auditory oddball ERP paradigm. RESULTS: Subjects with mild AD showed lower amplitude and increased latency for ERP features associated with attention, working memory, and executive function. These subjects also had decreased accuracy and longer reaction time in the target detection task associated with the ERP test. DISCUSSION: Analysis of ERP data showed significant changes in subjects with mild AD that are consistent with the cognitive deficits found in this population. The use of an integrated hardware/software system for data acquisition and automated data analysis methods make administration of ERP tests practical in outpatient settings.
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The long-term safety, tolerability, and efficacy of high-dose 13.3 mg/24 h rivastigmine patch in severe Alzheimer disease was evaluated in a 24-week, open-label extension to the double-blind ACTION study. Safety and tolerability, and efficacy on the Alzheimer's Disease Cooperative Study-Activities of Daily Living scale-Severe Impairment Version (ADCS-ADL-SIV), Severe Impairment Battery (SIB), and ADCS-Clinical Global Impression of Change (ADCS-CGIC) were assessed. Overall, 197 patients continued on 13.3 mg/24 h patch; 199 uptitrated from 4.6 mg/24 h to 13.3 mg/24 h patch. The incidence of adverse events (AEs), serious AEs and discontinuations due to AEs was similar in patients who continued on, and patients who uptitrated to, 13.3 mg/24 h patch (AEs: 57.9% and 59.8%; serious AEs: 16.2% and 16.1%; discontinuations: 11.2% and 12.1%, respectively). Larger mean changes from double-blind baseline were observed in patients uptitrated on the ADCS-ADL-SIV (-4.6; SD=8.7) and SIB (-7.0; SD=16.6), than those who continued on 13.3 mg/24 h patch (-3.9; SD=8.0 and -4.7; SD=16.8, respectively). ADCS-CGIC scores were comparable. There were no clinically relevant between-group differences in safety and tolerability. Greater decline was observed in patients with delayed uptitration to high-dose 13.3 mg/24 h patch than patients who continued on high-dose patch.
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Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/administración & dosificación , Rivastigmina/administración & dosificación , Accidentes por Caídas , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Inhibidores de la Colinesterasa/uso terapéutico , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Estudios Longitudinales , Masculino , Pruebas Neuropsicológicas , Estudios Prospectivos , Rivastigmina/uso terapéutico , Índice de Severidad de la Enfermedad , Parche Transdérmico , Resultado del Tratamiento , Infecciones Urinarias/inducido químicamente , Pérdida de PesoRESUMEN
We report the findings from a clinical trial in which a group of patients clinically diagnosed with probable Alzheimer's disease (AD) were discriminated from an age-matched group of healthy volunteers (HVs) with statistical significance (P<.001). The results from 20 patients with AD and 20 HVs were obtained by a Fluorescent Ligand Eye Scanning (FLES) technique that measures a fluorescent signature specific to an exogenous ligand bound to amyloid-ß in the lens of the eye. Sensitivity and specificity of 85% and 95%, respectively, have been achieved in predicting clinical diagnosis. Additionally, amyloid brain imaging using florbetapir F18 positron emission tomography shows significant correlation with the results obtained in the eye. Results of the study demonstrate the safety of the FLES system.
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Enfermedad de Alzheimer/diagnóstico , Péptidos beta-Amiloides/metabolismo , Encéfalo/diagnóstico por imagen , Cristalino/metabolismo , Espectrometría de Fluorescencia/métodos , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico por imagen , Compuestos de Anilina , Glicoles de Etileno , Femenino , Radioisótopos de Flúor , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: Rivastigmine displays dose-dependent efficacy on cognition in patients with Alzheimer's disease (AD), as measured by the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog). Subanalysis of the OPTIMA (OPtimising Transdermal Exelon In Mild-to-moderate Alzheimer's disease) study aimed to define ADAS-cog domains by factor analysis of individual items. Efficacy of 13.3 mg/24 h versus 9.5 mg/24 h rivastigmine patch on individual items and newly derived domains was assessed. METHODS: OPTIMA was a 48-week, double-blind (DB) study in patients with mild-to-moderate AD. Patients meeting pre-defined decline criteria during open-label treatment with 9.5 mg/24 h patch were randomized in the DB phase to 13.3 mg/24 h (n = 280) or 9.5 mg/24 h (n = 287) patch. ADAS-cog change from baseline was a co-primary outcome measure. Factor analysis categorized ADAS-cog items into newly derived domains. Change from DB-baseline was calculated for domains and individual items. RESULTS: Numerically, less decline was displayed with 13.3 mg/24 h versus 9.5 mg/24 h patch in the total ADAS-cog score at all time points (significant at Week 24, p = 0.027). Factor analysis identified two domains: memory and language. Significantly, less decline was observed on the memory domain with 13.3 mg/24 h versus 9.5 mg/24 h patch at Weeks 12, 24, and 48 (p < 0.05; observed cases). Three items (following commands, orientation, and word recognition) displayed numerically less decline with 13.3 mg/24 h versus 9.5 mg/24 h patch at all time points. No significant between-group differences were observed on the language domain. CONCLUSION: Results suggest that the greater cognitive efficacy of 13.3 mg/24 h versus 9.5 mg/24 h rivastigmine patch is driven primarily by effects on memory, particularly in the areas of following commands, orientation, and word recognition.
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Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/administración & dosificación , Cognición/efectos de los fármacos , Fármacos Neuroprotectores/administración & dosificación , Fenilcarbamatos/administración & dosificación , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/psicología , Escalas de Valoración Psiquiátrica Breve , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Análisis Factorial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rivastigmina , Índice de Severidad de la Enfermedad , Parche TransdérmicoRESUMEN
Neuropathologic heterogeneity is often present among Alzheimer disease (AD) patients. We sought to determine whether amyloid imaging measures of AD are affected by concurrent pathologies. Thirty-eight clinically and pathologically defined AD and 17 nondemented patients with quantitative florbetapir F-18 (F-AV-45) positron emission tomography (PET) imaging during life and postmortem histological ß-amyloid quantification and neuropathologic examination were assessed. AD patients were divided on the basis of concurrent pathologies, including those with Lewy bodies (LBs) (n = 21), white matter rarefaction (n = 27), severe cerebral amyloid angiopathy (n = 11), argyrophilic grains (n = 5), and TAR DNA binding protein-43 inclusions (n = 18). Many patients exhibited more than 1 type of concurrent pathology. The ratio of cortical to cerebellar amyloid imaging signal (SUVr) and immunohistochemical ß-amyloid load were analyzed in 6 cortical regions of interest. All AD subgroups had strong and significant correlations between SUVr and histological ß-amyloid measures (p µ 0.001). All AD subgroups had significantly greater amyloid measures versus nondemented patients, and mean amyloid measures did not significantly differ between AD subgroups. When comparing AD cases with and without each pathology, AD cases with LBs had significantly lower SUVr measures versus AD cases without LBs (p = 0.002); there were no other paired comparison differences. These findings indicate that florbetapir-PET imaging is not confounded by neuropathological heterogeneity within AD.
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Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/epidemiología , Compuestos de Anilina , Glicoles de Etileno , Radioisótopos de Flúor , Tomografía de Emisión de Positrones/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones/normasRESUMEN
OBJECTIVE: To discuss the pharmacology, mechanism of action, and chemical properties of the cholinesterase inhibitor (ChEI) rivastigmine; to provide a rationale for transdermal delivery and supportive clinical data, along with practical guidance on rivastigmine patch use in Alzheimer's disease and Parkinson's disease dementia. DATA SOURCES: Pivotal studies of rivastigmine capsules and patch were identified using PubMed and the rivastigmine US prescribing information. PubMed searches were performed in 2013 using rivastigmine as a keyword. STUDY SELECTION: English-language articles related to rivastigmine considered of relevance to primary care physicians were included. DATA SYNTHESIS: Pharmacologic differences exist between rivastigmine and ChEIs. Clinical studies demonstrate symptomatic efficacy of oral rivastigmine across all stages of Alzheimer's disease and mild-to-moderate Parkinson's disease dementia. However, gastrointestinal adverse events limit access to optimal therapeutic doses. Strategies that lower maximum plasma concentrations (Cmax) and prolong time to Cmax, ie, transdermal delivery, may improve tolerability. Clinical registration studies have demonstrated improved tolerability of rivastigmine 9.5-mg/24-h patch versus 6-mg twice-daily capsules in mild-to-moderate Alzheimer's disease, and a positive benefit-risk profile of 13.3-mg/24-h versus 9.5-mg/24-h patch in patients needing enhanced efficacy. Clinical data comparing 13.3-mg/24-h versus 4.6-mg/24-h patch in severe Alzheimer's disease demonstrated efficacy on cognition and activities of daily living. These data led to approval of rivastigmine patch in severe Alzheimer's disease. Transdermal delivery also has practical advantages, including simple, once-daily administration and a visual indicator of compliance. Potential application site reactions can be minimized and need not be a barrier to treatment. CONCLUSIONS: In addition to practical advantages, rivastigmine patch may improve clinical outcomes throughout the course of Alzheimer's disease by providing access to high-dose efficacy without compromising tolerability.
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INTRODUCTION: Souvenaid® containing Fortasyn® Connect is a medical food designed to support synapse synthesis in persons with Alzheimer's disease (AD). Fortasyn Connect includes precursors (uridine monophosphate; choline; phospholipids; eicosapentaenoic acid; docosahexaenoic acid) and cofactors (vitamins E, C, B12, and B6; folic acid; selenium) for the formation of neuronal membranes. Whether Souvenaid slows cognitive decline in treated persons with mild-to-moderate AD has not been addressed. METHODS: In a 24-week, double-masked clinical trial at 48 clinical centers, 527 participants taking AD medications [52% women, mean age 76.7 years (Standard Deviation, SD = 8.2), and mean Mini-Mental State Examination score 19.5 (SD = 3.1, range 14-24)] were randomized 1:1 to daily, 125-mL (125 kcal), oral intake of the active product (Souvenaid) or an iso-caloric control. The primary outcome of cognition was assessed by the 11-item Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-cog). Compliance was calculated from daily diary recordings of product intake. Statistical analyses were performed using mixed models for repeated measures. RESULTS: Cognitive performance as assessed by ADAS-cog showed decline over time in both control and active study groups, with no significant difference between study groups (difference =0.37 points, Standard Error, SE = 0.57, p = 0.513). No group differences in adverse event rates were found and no clinically relevant differences in blood safety parameters were noted. Overall compliance was high (94.1% [active] and 94.5% [control]), which was confirmed by significant changes in blood (nutritional) biomarkers. CONCLUSIONS: Add-on intake of Souvenaid during 24 weeks did not slow cognitive decline in persons treated for mild-to-moderate AD. Souvenaid was well tolerated in combination with standard care AD medications. TRIAL REGISTRATION: DUTCH TRIAL REGISTER NUMBER: NTR1683.
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AIMS: The 24-week, prospective, randomized, double-blind ACTION study investigated the efficacy, safety, and tolerability of 13.3 versus 4.6 mg/24 h rivastigmine patch in patients with severe Alzheimer's disease (AD). METHODS: Patients had probable AD and Mini-Mental State Examination scores ≥3-≤12. Primary outcome measures were as follows: Severe Impairment Battery (SIB) and AD Cooperative Study-Activities of Daily Living scale-Severe Impairment Version (ADCS-ADL-SIV). Secondary outcomes were as follows: ADCS-Clinical Global Impression of Change (ADCS-CGIC), 12-item Neuropsychiatric Inventory (NPI-12), and safety/tolerability. RESULTS: Of 1014 patients screened, 716 were randomized to 13.3 mg/24 h (N = 356) or 4.6 mg/24 h (N = 360) patch. Baseline characteristics/demographics were comparable. Completion rates were as follows: 64.3% (N = 229) with 13.3 mg/24 h and 65.0% (N = 234) with 4.6 mg/24 h patch. The 13.3 mg/24 h patch was significantly superior to 4.6 mg/24 h patch on cognition (SIB) and function (ADCS-ADL-SIV) at Week 16 (P < 0.0001 and P = 0.049, respectively) and 24 (primary endpoint; P < 0.0001 and P = 0.025). Significant between-group differences (Week 24) were observed on the ADCS-CGIC (P = 0.0023), not NPI-12 (P = 0.1437). A similar proportion of the 13.3 mg/24 h and 4.6 mg/24 h patch groups reported adverse events (AEs; 74.6% and 73.3%, respectively) and serious AEs (14.9% and 13.6%). CONCLUSIONS: The 13.3 mg/24 h patch demonstrated superior efficacy to 4.6 mg/24 h patch on SIB and ADCS-ADL-SIV, without marked increase in AEs, suggesting higher-dose patch has a favorable benefit-to-risk profile in severe AD.
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Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/psicología , Fármacos Neuroprotectores/administración & dosificación , Fenilcarbamatos/administración & dosificación , Índice de Severidad de la Enfermedad , Parche Transdérmico , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , RivastigminaRESUMEN
We report results of a clinical exploratory human trial involving 10 participants using a combination of a fluorescent ligand and a laser scanning device, SAPPHIRE System, as an aid in the diagnosis of Probable Alzheimer's disease (AD). To the best of our knowledge, this is the first time that such a technique has been used in vivo of a human lens. The primary goal of the clinical trial, in addition to safety assessment, was to evaluate efficacy of the system. By detecting specific fluorescent signature of ligand bound beta amyloid in the supranucleus (SN) region of the human lens, a twofold differentiation factor between AD patients and Control groups is achieved. Data from our studies indicates that deeper regions of the SN provide the highest measures of ligand bound fluorescence signal from both controls and patients with AD. In addition, we present preclinical studies that were performed to investigate the binding affinity of the ligand to beta amyloid and evaluate the pharmacokinetics of the ligand in rabbit eyes. Further studies are underway involving a larger population for statistical evaluation of the method.
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OBJECTIVE: To evaluate the performance characteristics of florbetapir F18 positron emission tomography (PET) in patients with Alzheimer's disease (AD), mild cognitive impairment (MCI), and healthy control subjects (HCs). METHODS: Florbetapir PET was acquired in 184 subjects (45 AD patients, 60 MCI patients, and 79 HCs) within a multicenter phase 2 study. Amyloid burden was assessed visually and quantitatively, and was classified as positive or negative. RESULTS: Florbetapir PET was rated visually amyloid positive in 76% of AD patients, 38% of MCI patients, and 14% of HCs. Eighty-four percent of AD patients, 45% of MCI patients, and 23% of HCs were classified as amyloid positive using a quantitative threshold. Amyloid positivity and mean cortical amyloid burden were associated with age and apolipoprotein E ε4 carrier status. CONCLUSIONS: : The data are consistent with expected rates of amyloid positivity among individuals with clinical diagnoses of AD and MCI, and indicate the potential value of florbetapir F18 PET as an adjunct to clinical diagnosis.
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Envejecimiento , Enfermedad de Alzheimer/diagnóstico por imagen , Proteínas Amiloidogénicas/metabolismo , Compuestos de Anilina , Disfunción Cognitiva/diagnóstico por imagen , Radioisótopos de Flúor , Estilbenos , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/genética , Apolipoproteína E4/genética , Disfunción Cognitiva/genética , Femenino , Humanos , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Tomografía de Emisión de PositronesRESUMEN
OBJECTIVES: Investigate apolipoprotein E ε4 (APOE4) gene and aging effects on florbetapir F18 positron emission tomography (PET) in normal aging and Alzheimer's disease (AD). METHODS: Florbetapir F18 PET images were analyzed from 245 participants, 18-92 years of age, from Avid Radiopharmaceutical's multicenter registered trials, including 86 younger healthy control volunteers (yHC), 61 older healthy control volunteers (oHC), 53 mild cognitive impairment (MCI) patients, and 45 AD dementia patients (DAT). Mean florbetapir standard uptake value ratios (SUVRs) were used to evaluate the effects of APOE4 carrier status, older age, and their interaction in each of these groups. RESULTS: In comparison with non-carriers, the APOE4 carriers in each of the oHC, MCI, and DAT groups had higher mean cortical-to-cerebellar florbetapir SUVRs, patterns of florbetapir PET elevations characteristic of DAT, and a higher proportion meeting florbetapir PET positivity criteria. Only the oHC group had a significant association between mean cortical florbetapir SUVRs and age. In cognitively normal adults, without regards to APOE4 genotype, amyloid began to increase at age 58 (95% confidence interval [CI]: 52.3-63.7), with a predicted typical age of florbetapir positivity occurring around age 71 years. Presence of the APOE4 gene reduced the age of predicted florbetapir positivity in normal aging to around age 56 years, approximately 20 years younger than non-carriers. INTERPRETATION: Cerebral amyloid deposition is associated with APOE4 carrier status in older healthy control subjects and symptomatic AD patients, and increases with age in older cognitively normal individuals. Amyloid imaging positivity appears to begin near age 56 years in cognitively intact APOE4 carriers and age 76 years in APOE4 non-carriers.