scholarly journals Effect of Age on Clinical Trial Outcome in Participants with Probable Alzheimer’s Disease

2021 ◽  
pp. 1-15
Author(s):  
Steven D. Targum ◽  
Lisa Fosdick ◽  
Kristen E. Drake ◽  
Paul B. Rosenberg ◽  
Anna D. Burke ◽  
...  

Background: Age may affect treatment outcome in trials of mild probable Alzheimer’s disease (AD). Objective: We examined age as a moderator of outcome in an exploratory study of deep brain stimulation targeting the fornix (DBS-f) region in participants with AD. Methods: Forty-two participants were implanted with DBS electrodes and randomized to double-blind DBS-f stimulation (“on”) or sham DBS-f (“off”) for 12 months. Results: The intervention was safe and well tolerated. However, the selected clinical measures did not differentiate between the “on” and “off” groups in the intent to treat (ITT) population. There was a significant age by time interaction with the Alzheimer’s Disease Assessment Scale; ADAS-cog-13 (p = 0.028). Six of the 12 enrolled participants <  65 years old (50%) markedly declined on the ADAS-cog-13 versus only 6.7%of the 30 participants≥65 years old regardless of treatment assignment (p = 0.005). While not significant, post-hoc analyses favored DBS-f “off” versus “on” over 12 months in the <  65 age group but favored DBS-f “on” versus “off” in the≥65 age group on all clinical metrics. On the integrated Alzheimer’s Disease rating scale (iADRS), the effect size contrasting DBS-f “on” versus “off” changed from +0.2 (favoring “off”) in the <  65 group to –0.52 (favoring “on”) in the≥65 age group. Conclusion: The findings highlight issues with subject selection in clinical trials for AD. Faster disease progression in younger AD participants with different AD sub-types may influence the results. Biomarker confirmation and genotyping to differentiate AD subtypes is important for future clinical trials.

1996 ◽  
Vol 8 (3) ◽  
pp. 397-411 ◽  
Author(s):  
Erich Mohr ◽  
Denise Walker ◽  
Christopher Randolph ◽  
Margaret Sampson ◽  
Tilak Mendis

Tests used as outcome measures in clinical trials of antidementia agents are not typically employed as part of diagnostic evaluations, and little information exists as to the sensitivity of these tests in terms of either differentiating demented patients from normal individuals or in distinguishing dementias of various types and etiologies. Sensitivity to mild dementia and sensitivity to impairment of various neuropsychological domains are, however, prerequisites for valid use of an instrument as an outcome measure in this context. The present study was undertaken to directly compare six different tests (three traditional psychometric tests and three clinical trial batteries) in terms of their sensitivity to detect and distinguish between mild dementia in patients with either Alzheimer's disease (n = 15) or Huntington's disease (n = 15), when compared to normal controls (n = 15). Tests included the Mattis Dementia Rating Scale, the Mini-Mental State Examination, the Wechsler Memory Scale-Revised, the Alzheimer's Disease Assessment Scale-Cognitive Subscale, the Computerized Drug Research (CDR) Cognitive Assessment System, and the Repeatable Battery for the Assessment of Dementia (RBAD). All of the tests were roughly equivalent in terms of their ability to discriminate normal subjects from mildly demented patients. Only the CDR and RBAD, however, were able to reliably discriminate between the two patient groups. The results are discussed in terms of the applicability of these tests as outcome measures for clinical trials in dementing disorders.


BMJ Open ◽  
2014 ◽  
Vol 4 (10) ◽  
pp. e006364 ◽  
Author(s):  
Brian Lawlor ◽  
Sean Kennelly ◽  
Sarah O'Dwyer ◽  
Fiona Cregg ◽  
Cathal Walsh ◽  
...  

IntroductionThis study is a European multicentre, randomised, double-blind, placebo-controlled trial investigating the efficacy and safety of nilvadipine as a disease course modifying treatment for mild-to-moderate Alzheimer's disease (AD) in a phase III study that will run for a period of 82 weeks with a treatment period of 78 weeks.Methods and analysisAdult patients, males and females over 50 years with mild-to-moderate AD as defined by the National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's disease and Related Disorders Association (NINCDS-ADRDA) criteria, will be included in the study. It aims to recruit a total of 500 patients with AD; 250 in the nilvadipine group and 250 in the placebo group. Participants will be randomised to receive nilvadipine, an 8 mg overencapsulated, sustained release capsule, or a matching overencapsulated placebo (sugar pill) for a period of 78 weeks of treatment. The primary efficacy outcome measure in this study is the change in cognitive function as assessed by the Alzheimer's disease Assessment Scale (ADAS-Cog 12) from baseline to the end of treatment duration (78 weeks). There are two key secondary outcome measures, the Clinical Dementia Rating Scale Sum of Boxes (CDR-sb) and the Disability Assessment for Dementia (DAD). If a statistically significant effect is seen in the primary outcome, CDR-sb will be considered to be a coprimary end point and only the DAD will contribute to the secondary outcome analysis.Ethics and disseminationThe study and all subsequent amendments have received ethical approval within each participating country according to national regulations. Each participant will provide written consent to participate in the study. All participants will remain anonymised throughout and the results of the study will be published in an international peer-reviewed journal.Trial registration numberEUDRACT Reference Number: 2012-002764-27.


2018 ◽  
Vol 15 (5) ◽  
pp. 429-442 ◽  
Author(s):  
Nishant Verma ◽  
S. Natasha Beretvas ◽  
Belen Pascual ◽  
Joseph C. Masdeu ◽  
Mia K. Markey ◽  
...  

Background: Combining optimized cognitive (Alzheimer's Disease Assessment Scale- Cognitive subscale, ADAS-Cog) and atrophy markers of Alzheimer's disease for tracking progression in clinical trials may provide greater sensitivity than currently used methods, which have yielded negative results in multiple recent trials. Furthermore, it is critical to clarify the relationship among the subcomponents yielded by cognitive and imaging testing, to address the symptomatic and anatomical variability of Alzheimer's disease. Method: Using latent variable analysis, we thoroughly investigated the relationship between cognitive impairment, as assessed on the ADAS-Cog, and cerebral atrophy. A biomarker was developed for Alzheimer's clinical trials that combines cognitive and atrophy markers. Results: Atrophy within specific brain regions was found to be closely related with impairment in cognitive domains of memory, language, and praxis. The proposed biomarker showed significantly better sensitivity in tracking progression of cognitive impairment than the ADAS-Cog in simulated trials and a real world problem. The biomarker also improved the selection of MCI patients (78.8±4.9% specificity at 80% sensitivity) that will evolve to Alzheimer's disease for clinical trials. Conclusion: The proposed biomarker provides a boost to the efficacy of clinical trials focused in the mild cognitive impairment (MCI) stage by significantly improving the sensitivity to detect treatment effects and improving the selection of MCI patients that will evolve to Alzheimer’s disease.


Author(s):  
Zahra Ayati ◽  
Guoyan Yang ◽  
Mohammad Hossein Ayati ◽  
Seyed Ahmad Emami ◽  
Dennis Chang

Abstract Background Saffron (stigma of Crocus sativus L.) from Iridaceae family is a well-known traditional herbal medicine that has been used for hundreds of years to treat several diseases such as depressive mood, cancer and cardiovascular disorders. Recently, anti-dementia property of saffron has been indicated. However, the effects of saffron for the management of dementia remain controversial. The aim of the present study is to explore the effectiveness and safety of saffron in treating mild cognitive impairment and dementia. Methods An electronic database search of some major English and Chinese databases was conducted until 31st May 2019 to identify relevant randomised clinical trials (RCT). The primary outcome was cognitive function and the secondary outcomes included daily living function, global clinical assessment, quality of life (QoL), psychiatric assessment and safety. Rev-Man 5.3 software was applied to perform the meta-analyses. Results A total of four RCTs were included in this review. The analysis revealed that saffron significantly improves cognitive function measured by the Alzheimer’s Disease Assessment Scale-cognitive subscale (ADAS-cog) and Clinical Dementia Rating Scale-Sums of Boxes (CDR-SB), compared to placebo groups. In addition, there was no significant difference between saffron and conventional medicine, as measured by cognitive scales such as ADAS-cog and CDR-SB. Saffron improved daily living function, but the changes were not statistically significant. No serious adverse events were reported in the included studies. Conclusions Saffron may have the potential to improve cognitive function and activities of daily living in patients with Alzheimer’s disease and mild cognitive impairment (MCI). However, due to limited high-quality studies there is insufficient evidence to make any recommendations for clinical use. Further clinical trials on larger sample sizes are warranted to shed more light on its efficacy and safety.


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Shifu Xiao ◽  
Piu Chan ◽  
Tao Wang ◽  
Zhen Hong ◽  
Shuzhen Wang ◽  
...  

Abstract Background New therapies are urgently needed for Alzheimer’s disease (AD). Sodium oligomannate (GV-971) is a marine-derived oligosaccharide with a novel proposed mechanism of action. The first phase 3 clinical trial of GV-971 has been completed in China. Methods We conducted a phase 3, double-blind, placebo-controlled trial in participants with mild-to-moderate AD to assess GV-971 efficacy and safety. Participants were randomized to placebo or GV-971 (900 mg) for 36 weeks. The primary outcome was the drug-placebo difference in change from baseline on the 12-item cognitive subscale of the Alzheimer’s Disease Assessment Scale (ADAS-cog12). Secondary endpoints were drug-placebo differences on the Clinician’s Interview-Based Impression of Change with caregiver input (CIBIC+), Alzheimer’s Disease Cooperative Study-Activities of Daily Living (ADCS-ADL) scale, and Neuropsychiatric Inventory (NPI). Safety and tolerability were monitored. Results A total of 818 participants were randomized: 408 to GV-971 and 410 to placebo. A significant drug-placebo difference on the ADAS-Cog12 favoring GV-971 was present at each measurement time point, measurable at the week 4 visit and continuing throughout the trial. The difference between the groups in change from baseline was − 2.15 points (95% confidence interval, − 3.07 to − 1.23; p < 0.0001; effect size 0.531) after 36 weeks of treatment. Treatment-emergent adverse event incidence was comparable between active treatment and placebo (73.9%, 75.4%). Two deaths determined to be unrelated to drug effects occurred in the GV-971 group. Conclusions GV-971 demonstrated significant efficacy in improving cognition with sustained improvement across all observation periods of a 36-week trial. GV-971 was safe and well-tolerated. Trial registration ClinicalTrials.gov, NCT02293915. Registered on November 19, 2014


Author(s):  
S. Gauthier ◽  
R. Bouchard ◽  
Y. Bacher ◽  
P. Bailey ◽  
H. Bergman ◽  
...  

ABSTRACT:Since the discovery of a significant depletion of acetylcholine in discrete areas of the brain of patients affected by Alzheimer's disease, attempts at symptomatic therapy have concentrated on acetylcholine supplementation, an approach that is based upon the efficacy of dopaminergic supplementation therapy for Parkinson's disease. Choline, then lecithin, used orally, failed to improve symptoms but the hypothesis that long-term choline supplementation might stabilize the course of Alzheimer's disease remains to be tested. Nerve growth factor may also offer that possibility. Bethanechol administered intracerebroventricularly did not help when a fixed dose was used but individual titration of more selective muscarinic agonists may prove more effective. In this article we report that tetrahydroaminoacridine (THA), given together with highly concentrated lecithin, appears to bring improvement in cognition and in functional autonomy using the Mini Mental State and the Rapid Disability Rating Scale-2 respectively, without change in behavior as reflected by the Behave-AD. Double-blind cross-over studies are in progress to establish its efficacy. Improvement in study design and means of assessment of cognition, functional autonomy and behavior have been made possible by these drug trials.


1998 ◽  
Vol 10 (2) ◽  
pp. 193-203 ◽  
Author(s):  
John O. Brooks ◽  
Jerome A. Yesavage ◽  
Angelico Carta ◽  
Daniele Bravi

Objectives: To assess the longitudinal effects of acetyl-L-carnitine (ALC) on patients diagnosed with Alzheimer's disease. Design: Longitudinal, double-blind, parallel-group, placebocontrolled. Setting: Twenty-four outpatient sites across the United States. Participants: A total of 334 subjects diagnosed with probable Alzheimer's disease by NINCDS-ADRDA criteria. These data were originally reported by Thal and colleagues (1996). Measurements: Cognitive subscale of the Alzheimer Disease Assessment Scale (ADAS) given every 3 months for 1 year. Results: The average rate of change was estimated using the trilinear approach, which allows for periods of both change and stability. Both the ALC group and the placebo group exhibited the same mean rate of change on the ADAS (0.68 points/month). However, a multiple regression analysis revealed a statistically significant Age × Drug interaction characterized by younger subjects benefiting more from ALC treatment than older subjects. Further analyses suggested that the optimal, though not statistically significant, cutpoint for ALC benefit was 61 years of age. Conclusions: ALC slows the progression of Alzheimer's disease in younger subjects, and the use of the trilinear approach to estimate the average rate of change may prove valuable in pharmacological trials.


2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Weidong Pan ◽  
Qiudong Wang ◽  
Shin Kwak ◽  
Yu Song ◽  
Baofeng Qin ◽  
...  

We evaluated the effects of the traditional Chinese medicine (TCM) Shen-Zhi-Ling oral liquid (SZL) on the behavioral and psychological symptoms of dementia (BPSD) in patients with Alzheimer’s disease (AD). Among 98 patients with AD and BPSD enrolled (mean age, 57.2 ± 8.9 years old), 91 (M = 55,F = 36; mean age, 57.2 ± 9.7 years old) completed the study. Patients took either SZL (n=45) or placebo granules (n=46) in a double-blind manner for 20 weeks while maintaining other anticognitive medications unchanged. Changes in BPSD between week 0, week 10, week 20, and week 25 were assessed using the behavioral pathology in Alzheimer’s disease (BEHAVE-AD) rating scale and the neuropsychiatric inventory (NPI), detrended fluctuation analysis (DFA) represented by diurnal activity (DA), evening activity (EA), and nocturnal activity (NA) according to actigraphic recordings. SZL but not placebo oral liquid delayed the development of BPSD significantly according to the changes in some of the clinical scores and the EA and NA parameters of DFA at week 20 compared with week 0. No side effects were observed in laboratory tests. The results indicate that SZL might delay the development of BPSD in AD patients and thus is a potentially suitable drug for long-term use.


Author(s):  
Kenneth Rockwood ◽  
B. Lynn Beattie ◽  
M. Robin Eastwood ◽  
Howard Feldman ◽  
Erich Mohr ◽  
...  

ABSTRACT:Objectives:We tested the efficacy and safety of linopirdine, a novel phenylindolinone, in the treatment of Alzheimer's disease.Methods:A multicentre, randomized, double-blind, parallel group, placebo-controlled trial of linopirdine (30 mg three times per day or placebo). Patients (n = 382, 55% male, 98% Caucasian, age range 51-95 years) with mild or moderate Alzheimer's disease, of whom 375 received at least one treatment dose were analysed. There were no important differences between the groups at baseline.Results:No difference was seen in Clinical Global Impression scores between patients receiving placebo and those receiving linopirdine (n = 189). Small differences in the Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog) scores were seen throughout the study favouring linopirdine; at 6 months the ADAS-Cog scores were 20.2 (linopirdine) and 22.1 (placebo) p = 0.01.Conclusions:This trial did not detect clinically meaningful differences in patients receiving linopirdine for 6 months, despite evidence of a small degree of improved cognitive function. Further studies may benefit from more sensitive tests of treatment effects in Alzheimer's disease.


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