Effects of a combined transcranial magnetic stimulation (TMS) and cognitive training intervention in patients with Alzheimer's disease.

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.

Effectiveness of Florbetapir PET Imaging in Changing Patient Management.

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.

A 24-Week, Open-Label Extension Study to Investigate the Long-term Safety, Tolerability, and Efficacy of 13.3 mg/24 h Rivastigmine Patch in Patients With Severe Alzheimer Disease.

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.

Adaptive, dose-finding phase 2 trial evaluating the safety and efficacy of ABT-089 in mild to moderate Alzheimer disease.

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.

Efficacy of higher-dose 13.3 mg/24 h (15 cm2) rivastigmine patch on the Alzheimer's Disease Assessment Scale-cognitive subscale: domain and individual item analysis.

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.

Potential impact of amyloid imaging on diagnosis and intended management in patients with progressive cognitive decline.

Florbetapir F18 has been approved by the Food and Drug Administration for in vivo assessment of amyloid pathology in patients undergoing evaluation for Alzheimer disease (AD). The aim of this study was to determine the impact of amyloid imaging on the diagnoses and management of patients undergoing evaluation for cognitive decline. Patients were recruited to participate at 19 clinical sites. The site physician provided a provisional diagnosis, an estimate of their diagnostic confidence, and their plan for diagnostic evaluation and management both before and after receiving the results from amyloid imaging with florbetapir F18. Analyses compared the frequency of AD and non-AD diagnoses, plans for ancillary testing, and intended patient management before and after florbetapir imaging. A total of 229 patients participated in the trial (113 amyloid positive, 116 amyloid negative). After receiving the results of the florbetapir scan, diagnosis changed in 125/229, or 54.6% [95% confidence intervals (CI), 48.1%-60.9%], of cases, and diagnostic confidence increased by an average of 21.6% (95% CI, 18.3%-24.8%). A total of 199/229 or 86.9% (95% CI, 81.9%-90.7%) of cases had at least 1 change in their management plan. Intended cholinesterase inhibitor or memantine treatment increased by 17.7% (95% CI, 11.8%-25.8%) of all cases with positive scans and decreased by 23.3% (95% CI, 16.5%-31.8%) of all those with negative scans. Among subjects who had not yet undergone a completed work up, planned brain structural imaging (computed tomographic/magnetic resonance imaging) decreased by 24.4% (95% CI, 17.5%-32.8%) and planned neuropsychological testing decreased by 32.8% (95% CI, 25.0%-41.6%). In summary, amyloid imaging results altered physician's diagnostic thinking, intended testing, and management of patients undergoing evaluation for cognitive decline.

Florbetapir (F18-AV-45) PET to assess amyloid burden in Alzheimer's disease dementia, mild cognitive impairment, and normal aging.

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.

Concurrent onabotulinumtoxinA treatment of cervical dystonia and concomitant migraine.

OBJECTIVE: The objective of this study was to assess the clinical benefits of onabotulinumtoxinA (BOTOX®) treatment on the symptoms of cervical dystonia and the frequency, severity, and associated symptoms of migraine in patients with cervical dystonia and concurrent migraine. BACKGROUND: Botulinum toxin is established as first-line treatment of cervical dystonia. Recent clinical trials have shown onabotulinumtoxinA to be an effective prophylactic therapy for patients with chronic migraine, and onabotulinumtoxinA has been approved for use in this patient population by the Food and Drug Administration. Patients with headache associated with cervical dystonia have been identified as a specific subpopulation of patients in whom botulinum toxin treatment may be effective for controlling the symptoms of both conditions. METHODS: An open-label pilot study was conducted for 7.5 months in patients at least 18 years old with primary cervical dystonia of moderate severity (baseline rating of at least 20 on the Toronto Western Spasmodic Torticollis Rating Scale) complicated by migraine headache meeting the International Classification of Headache Disorders-II criteria for migraines with or without aura. Each patient received 2 cycles of treatment at Visit 3 (baseline) and Visit 6 (Day 90). For cervical dystonia, each patient was injected with a maximum of 175 units. At the same visit, a maximum of 125 units was also injected for migraine using a fixed-site, fixed-dose injection paradigm, with additional cervical dystonia injection-site treatment to a maximum dose of 300 units. Patients were assessed following onabotulinumtoxinA injection and at follow-up on Visit 4 (Day 30), Visit 5 (Day 60), Visit 6 (Day 90), and at Visits 7, 8, and 9 (Days 120, 150, and 180). The primary outcome measures for this study were change in Toronto Western Spasmodic Torticollis Rating Scale total score for cervical dystonia and frequency of headache episodes per 28-day period. Migraine episodes were defined as at least 4 hours of sustained pain with no upper limit. An episode was considered new if the patient was pain free for at least 24 hours. Secondary study end points included number of headache days per month, headache intensity, headache disability (assessed using Headache Impact Test-6 and the Migraine Disability Assessment score scales), acute headache medication use, resource utilization, and allodynia pain. Adverse events were reported. RESULTS: A total of 25 patients (24 women, mean age 50.5 years; mean age of disease onset 21.9 years) were enrolled in the study. Patients experienced improvement in cervical dystonia symptoms with significant reductions from baseline in Toronto Western Spasmodic Torticollis Rating Scale scores at 30, 60, 90, 120, 150, and 180 days (-9.84 ± 8.49, -12.67 ± 8.22, -13.63 ± 7.27, -14.92 ± 7.05, -14.76 ± 6.97, -14.49 ± 6.14, respectively, P < .0001 at all time points from a baseline of 31.03 ± 3.61). Changes from baseline were assessed using the t-test. Reductions in the number of headache episodes from baseline on concurrent onabotulinumtoxinA treatment for coexistent chronic migraine did not attain significance. However, patients experienced significant reductions from baseline in the number of headache days at 90, 120, and 180 days (-3.39 ± 6.78, P = .0289; -4.29 ± 7.94, P = .0194; -4.38 ± 7.99, P = .0178, respectively, from a baseline of 15.33 ± 6.76). Changes from baseline were assessed using the t-test. The change from baseline in Headache Impact Test-6 total scores was significant at 30, 60, 90, 150, and 180 days (3.21 ± 4.14, P = .0009; -3.04 ± 4.04, P = .0012; -2.41 ± 2.79, P = .0006; -2.59 ± 3.87, P = .0050; -3.09 ± 3.80, respectively, from a baseline of 22.68 ± 3.20). Changes from baseline were assessed using the t-test. The change from baseline in Migraine Disability Assessment was significant at 120, 150, and 180 days (-38.09 ± 47.87, P < .0001, Wilcoxon signed rank test; -16.91 ± 62.69, P = .0358, Wilcoxon signed rank test; -23.73 ± 40.57, P = .0122, t-test, respectively, from a baseline of 56.68 ± 50.41). There were no serious adverse events or treatment-related discontinuations. CONCLUSIONS: Concurrent treatment with onabotulinumtoxinA is effective and well tolerated in controlling the symptoms of cervical dystonia complicated by concurrent migraine.

Use of florbetapir-PET for imaging beta-amyloid pathology.

CONTEXT: The ability to identify and quantify brain ß-amyloid could increase the accuracy of a clinical diagnosis of Alzheimer disease. OBJECTIVE: To determine if florbetapir F 18 positron emission tomographic (PET) imaging performed during life accurately predicts the presence of ß-amyloid in the brain at autopsy. DESIGN, SETTING, AND PARTICIPANTS: Prospective clinical evaluation conducted February 2009 through March 2010 of florbetapir-PET imaging performed on 35 patients from hospice, long-term care, and community health care facilities near the end of their lives (6 patients to establish the protocol and 29 to validate) compared with immunohistochemistry and silver stain measures of brain ß-amyloid after their death used as the reference standard. PET images were also obtained in 74 young individuals (18-50 years) presumed free of brain amyloid to better understand the frequency of a false-positive interpretation of a florbetapir-PET image. MAIN OUTCOME MEASURES: Correlation of florbetapir-PET image interpretation (based on the median of 3 nuclear medicine physicians' ratings) and semiautomated quantification of cortical retention with postmortem ß-amyloid burden, neuritic amyloid plaque density, and neuropathological diagnosis of Alzheimer disease in the first 35 participants autopsied (out of 152 individuals enrolled in the PET pathological correlation study). RESULTS: Florbetapir-PET imaging was performed a mean of 99 days (range, 1-377 days) before death for the 29 individuals in the primary analysis cohort. Fifteen of the 29 individuals (51.7%) met pathological criteria for Alzheimer disease. Both visual interpretation of the florbetapir-PET images and mean quantitative estimates of cortical uptake were correlated with presence and quantity of ß-amyloid pathology at autopsy as measured by immunohistochemistry (Bonferroni ρ, 0.78 [95% confidence interval, 0.58-0.89]; P <.001]) and silver stain neuritic plaque score (Bonferroni ρ, 0.71 [95% confidence interval, 0.47-0.86]; P <.001). Florbetapir-PET images and postmortem results rated as positive or negative for ß-amyloid agreed in 96% of the 29 individuals in the primary analysis cohort. The florbetapir-PET image was rated as amyloid negative in the 74 younger individuals in the nonautopsy cohort. CONCLUSIONS: Florbetapir-PET imaging was correlated with the presence and density of ß-amyloid. These data provide evidence that a molecular imaging procedure can identify ß-amyloid pathology in the brains of individuals during life. Additional studies are required to understand the appropriate use of florbetapir-PET imaging in the clinical diagnosis of Alzheimer disease and for the prediction of progression to dementia.

Magnetic resonance imaging and neuropsychological results from a trial of memantine in Alzheimer's disease.

BACKGROUND: This study was designed to assess changes in brain volume and cognitive abilities in memantine-treated patients with Alzheimer's disease (AD) by using an exploratory, single-arm, delayed-start design. METHODS: Cholinesterase inhibitor-treated patients with AD (N = 47; Mini-Mental State Examination score range: 15-23) were enrolled in an observational lead-in period (weeks: 1-24), followed by an open-label period of add-on memantine treatment (weeks: 25-48). The patients underwent magnetic resonance imaging at weeks 0 (baseline), 24 (immediately before memantine initiation), and 48 (endpoint), and a battery of neuropsychological tests at weeks 0, 24, 28, 36, and 48. The primary outcome measure was the annualized rate of change (%) in total brain volume (TBV) between the two study periods. Data were analyzed using paired t-tests. RESULTS: There were no statistically significant differences in the rates of change in TBV, ventricular volume, or left hippocampal volume between the study periods; however, the memantine treatment period was associated with a significantly slower right hippocampal atrophy (-5.5% ± 12.0% vs -10.8% ± 7.2%; P = .038). Memantine treatment was also associated with superior performances on the Boston Naming Test (P = .034) and the Trail Making Test, Part B (P = .001), but also with a higher number of errors (i.e., repetitions and intrusions) on the California Verbal Learning Test. Memantine was found to be safe and well tolerated. CONCLUSIONS: In this study, no difference in the rates of TBV change between the two periods was observed; however, memantine treatment was found to be associated with slowing of right hippocampal atrophy, and with improvement on one test of executive functioning as well as a test of confrontation naming ability. Trials using structural magnetic resonance imaging and a delayed-start design may be a feasible option for the assessment of treatments for AD.

Safety and tolerability of the rivastigmine patch: results of a 28-week open-label extension.

The primary objective of the open-label extension was to evaluate the long-term safety and tolerability of a transdermal rivastigmine patch up to 1 year, as a novel approach to treatment in Alzheimer disease. This was a 28-week extension to a 24-week, double-blind, double-dummy, placebo-controlled, and active-controlled study evaluating rivastigmine patches [9.5 mg/24 h (10 cm2) and 17.4 mg/24 h (20 cm2)] and oral capsules (3 to 6 mg twice-daily). Patients entering the extension were switched directly to 9.5 mg/ 24 h rivastigmine patch and increased to 17.4 mg/24 h patch, irrespective of their double-blind study treatment. Primary measures included safety and tolerability assessments, including adverse events and serious adverse events. Of 1195 patients randomized to treatment, 870 (72.8%) completed the double-blind study and entered the open-label extension. During weeks 1 to 4 of the extension, 9.5 mg/24 h rivastigmine patch was well tolerated overall by patients formerly randomized to rivastigmine capsule or patch groups: < or =2.5% reported nausea and < or =1.9% reported vomiting. No unexpected safety issues arose, and skin tolerability was good; similar to the double-blind study. During the 28-week, open-label extension phase, the patch seemed to be well tolerated with a favorable safety profile.

Safety and efficacy of rivastigmine in patients with Alzheimer's disease not responding adequately to donepezil: an open-label study.

OBJECTIVE: Switching patients with Alzheimer's disease from one cholinesterase inhibitor to another represents a viable option for patients not responding to current therapy. The objective of this large U.S.-based study was to evaluate the safety and efficacy of a treatment switch to rivastigmine in patients not responding adequately to or declining on treatment with donepezil. METHOD: In this 26-week, prospective, open-label, single-arm, multicenter study conducted from April 24, 2003, to June 25, 2004, patients with mild-to-moderate Alzheimer's disease (DSM-IV-TR criteria) who were not responding to donepezil were treated with rivastigmine 3-12 mg/day. Safety and tolerability were measured by the occurrence of adverse events and patient disposition. Treatment effects on global functioning were assessed using the Clinical Global Impression of Change (CGIC) scale. RESULTS: Two hundred seventy patients with a mean age of 78.5 (SD = 7.56) years and a mean duration of dementia of 3.5 (SD = 2.06) years were included in the study. Sixty-nine percent of patients completed the study with 17.8% discontinuing due to adverse events. Eighty-three percent of patients reported at least 1 adverse event, with the most frequently occurring adverse events affecting the gastrointestinal system (54%). The majority of patients were reported to have either improvement or no decline on the CGIC. A limitation of the study is that the interpretation of the results is based on an overall completion rate of 69%. CONCLUSION: Immediately switching patients from donepezil to rivastigmine without a washout period was safe and well tolerated in the current study. Additionally, these results suggest that patients not responding adequately to or declining while taking donepezil may improve or stabilize after switching to rivastigmine.

Use of Flutemetamol F 18-Labeled Positron Emission Tomography and Other Biomarkers to Assess Risk of Clinical Progression in Patients With Amnestic Mild Cognitive Impairment.

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.

Long-Term Extensions of Randomized Vaccination Trials of ACC-001 and QS-21 in Mild to Moderate Alzheimer's Disease.

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.

Performance of [18F]flutemetamol amyloid imaging against the neuritic plaque component of CERAD and the current (2012) NIA-AA recommendations for the neuropathologic diagnosis of Alzheimer's disease.

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.

Two Phase 2 Multiple Ascending-Dose Studies of Vanutide Cridificar (ACC-001) and QS-21 Adjuvant in Mild-to-Moderate Alzheimer's Disease.

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 (n = 245). 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.

Switching From Donepezil to Rivastigmine Is Well Tolerated: Results of an Open-Label Safety and Tolerability Study.

Background: Transitioning patients between cholinesterase inhibitors was thought to require a washout period to avoid cholinergic toxicity; however, evidence suggests that abrupt discontinuation of donepezil may lead to cognitive decline. We evaluated the safety and tolerability of an immediate switch from donepezil to rivastigmine.Method: This is an analysis of the safety and tolerability data from the first 28 days of an open-label, multicenter, prospective trial, conducted from August 2002 to August 2003, in which patients satisfying NINCDS-ADRDA criteria for probable Alzheimer's disease were administered rivastigmine 1.5 mg b.i.d. within 24 to 36 hours of donepezil discontinuation. Results are compared with adverse event rates from a retrospective analysis of a pivotal, placebo-controlled trial examining patients not previously treated with a cholinesterase inhibitor.Results: Fifty-eight of 61 patients completed the first 28 days, with no suspected drug-related discontinuations during this period. Incidence of overall gastrointestinal adverse events at day 7 was 8.2%, and at day 28 was 11.5%. The corresponding rate for rivastigmine-treated patients in the retrospective analysis of the pivotal trial for day 7 was 3.3%.Conclusion: These study results suggest that transitioning patients from donepezil to rivastigmine without a washout period is safe and well tolerated.

Evaluating Response to High-Dose 13.3 mg/24 h Rivastigmine Patch in Patients with Severe Alzheimer's Disease.

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.

Detection of Amyloid ß Signature in the Lens and Its Correlation in the Brain to Aid in the Diagnosis of Alzheimer's Disease.

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.

A clinical trial to validate event-related potential markers of Alzheimer's disease in outpatient settings.

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.