The comparative efficacy and safety of cholinesterase inhibitors in patients with mild-to-moderate Alzheimer's disease: a Bayesian network meta-analysis

Depressive symptoms in the entire spectrum of cognitive ageing in Greece: evidence from the Hellenic Longitudinal Investigation of Aging and Diet (HELIAD)

OBJECTIVES

To study (i) the prevalence of mild and moderate-to-severe depressive symptoms in the entire spectrum of cognitive ageing in Greece and (ii) the relationship between these symptoms and demographic and clinical data.

METHODS

The study was based on the randomly selected cohort of the Hellenic Longitudinal Investigation of Aging and Diet (HELIAD). Depressive symptoms were assessed with the 15-item version of the Geriatric Depression Scale. Participants also received a comprehensive neuropsychological assessment, while the clinical diagnoses of dementia and mild cognitive impairment were established according to international diagnostic criteria. Statistical analyses relied on comparison tests and a logistic (proportional odds) ordinal regression model.

RESULTS

Depressive symptoms were detected in 19.5% of the 1936 study participants, while 11.3% of both people with MCI and dementia had moderate-to-severe depressive symptoms. The regression model revealed that older adults with more severe depressive symptoms were more likely female, cognitively impaired, less educated, were treated with psychotropic medication and lived in Attica versus Thessaly.

CONCLUSIONS

Since depressive symptoms were detected in almost one in five older adults, healthcare professionals in Greece should safeguard the timely detection and effective treatment of such symptoms and the post-diagnostic care of older adults with depression.

Alzheimer's disease current therapies, novel drug delivery systems and future directions for better disease management

Alzheimer's disease (AD), is a neurodegenerative disorder that escalates with time, exerting a significant impact on physical and mental health and leading to death. The prevalence of AD is progressively rising along with its associated economic burden and necessitates effective therapeutic approaches in the near future. This review paper aims to offer an insightful overview of disease pathogenesis, current FDA-approved drugs, and drugs in different clinical phases. It also explores innovative formulations and drug delivery strategies, focusing on nanocarriers and long-acting medications (LAMs) to enhance treatment efficacy and patient adherence. The review also emphasizes preclinical evidence related to nanocarriers and their potential to improve drug bioavailability, pharmacokinetics, and pharmacodynamics parameters, while also highlighting their ability to minimize systemic side effects. By providing a comprehensive analysis, this review furnishes valuable insights into different pathophysiological mechanisms for future drug development. It aims to inform the development of treatment strategies and innovative formulation approaches for delivering existing molecules in Alzheimer's disease, ultimately striving to improve patient compliance.

Acetyl-cholinesterase-inhibitors reconsidered. A narrative review of post-marketing studies on Alzheimer's disease

The real efficacy of Acetyl-cholinesterase-inhibitors (AChEI) has been questioned. In this narrative review we evaluated their effect on cognitive decline, measured by Mini Mental State Examination (MMSE), and on total mortality rates in patients with Alzheimer's disease (AD) recruited into post-marketing open/non-randomized/retrospective studies. In AD patients treated with AChEI, the mean MMSE loss ranged from 0.2 to 1.37 points/years, compared with 1.07-3.4 points/years in non-treated patients. Six studies also reported data about survival; a reduction in total mortality relative risk between 27% and 42% was observed, over a period of 2-8 years. The type of studies and the use of MMSE to assess cognitive decline, may have introduced several biases. However, the clinical effects of AChEI seem to be of the same order of magnitude as the drugs currently used in most common chronic disorders, as regards progression of the disease and total mortality. In the absence of long-term randomized trials on "standard" unselected AD outpatients, open/retrospective studies and health databases represent the best available evidence on the possible effect of AChEI in the real-word setting. Our data support the clinical benefit of AChEI in older patients affected by AD.

Behavioral Treatment for Speech and Language in Primary Progressive Aphasia and Primary Progressive Apraxia of Speech: A Systematic Review

Primary progressive aphasia (PPA) and primary progressive apraxia of speech (PPAOS) are neurodegenerative syndromes characterized by progressive decline in language or speech. There is a growing number of studies investigating speech-language interventions for PPA/PPAOS. An updated systematic evaluation of the treatment evidence is warranted to inform best clinical practice and guide future treatment research. We systematically reviewed the evidence for behavioral treatment for speech and language in this population. Reviewed articles were published in peer-reviewed journals through 31 May 2021. We evaluated level of evidence, reporting quality, and risk of bias using a modified version of the American Speech-Language Hearing Association (ASHA) Levels of Evidence, an appraisal point system, additional reporting quality and internal/external validity items, and, as appropriate, the Single Case Experimental Design Scale or the Physiotherapy Evidence Database - PsycBITE Rating Scale for Randomized and Non-Randomized Controlled Trials. Results were synthesized using quantitative summaries and narrative review. A total of 103 studies reported treatment outcomes for 626 individuals with PPA; no studies used the diagnostic label PPAOS. Most studies evaluated interventions for word retrieval. The highest-quality evidence was provided by 45 experimental and quasi-experimental studies (16 controlled group studies, 29 single-subject designs). All (k = 45/45) reported improvement on a primary outcome measure; most reported generalization (k = 34/43), maintenance (k = 34/39), or social validity (k = 17/19) of treatment for at least one participant. The available evidence supports speech-language intervention for persons with PPA; however, treatment for PPAOS awaits systematic investigation. Implications and limitations of the evidence and the review are discussed.

Understanding neuropsychiatric symptoms in Alzheimer's disease: challenges and advances in diagnosis and treatment

Neuropsychiatric symptoms (NPS) in Alzheimer's disease (AD) affect up to 97% of AD patients, with an estimated 80% of current AD patients experiencing these symptoms. Common AD-associated NPS include depression, anxiety, agitation, aggression, and apathy. The severity of NPS in AD is typically linked to the disease's progression and the extent of cognitive decline. Additionally, these symptoms are responsible for a significant increase in morbidity, mortality, caregiver burden, earlier nursing home placement, and greater healthcare expenditure. Despite their high prevalence and significant impact, there is a notable lack of clinical research on NPS in AD. In this article, we explore and analyze the prevalence, symptom manifestations, challenges in diagnosis, and treatment options of NPS associated with AD. Our literature review reveals that distinguishing and accurately diagnosing the NPS associated with AD remains a challenging task in clinical settings. It is often difficult to discern whether NPS are secondary to pathophysiological changes from AD or are comorbid psychiatric conditions. Furthermore, the availability of effective pharmaceutical interventions, as well as non-pharmacotherapies for NPS in AD, remains limited. By highlighting the advance and challenges in diagnosis and treatment of AD-associated NPS, we aspire to offer new insights into the complexity of identifying and treating these symptoms within the context of AD, and contribute to a deeper understanding of the multifaceted nature of NPS in AD.

Identifying factors influencing cognitive outcomes after anodal transcranial direct current stimulation in older adults with and without cognitive impairment: A systematic review

Anodal transcranial direct current stimulation (tDCS) can improve cognition in healthy older adults, those with Alzheimer's disease (AD) and mild cognitive impairment (MCI), albeit with considerable variability in response. This systematic review identifies interindividual factors that may influence tDCS outcomes in older individuals with or without cognitive impairment. Peer-reviewed articles were included if they assessed whether cognitive outcomes (memory or global cognition) after tDCS were associated with pre-intervention factors in healthy older adults or individuals with AD/MCI. We identified eight factors that may affect cognitive outcomes after tDCS. Improved tDCS outcomes were predicted by lower baseline cognitive function when tDCS was combined with a co-intervention (but not when used alone). Preserved brain structure and better baseline functional connectivity, genetic polymorphisms, and the use of concomitant medications may predict better tDCS outcomes, but further research is warranted. tDCS outcomes were not consistently associated with age, cognitive reserve, sex, and AD risk factors. Accounting for individual differences in baseline cognition, particularly for combined interventions, may thus maximize the therapeutic potential of tDCS.

Treatment of Vascular and Neurodegenerative Forms of Cognitive Impairment and Dementias

Ideally, dementia care should be provided by a collaborative team. Eligible patients should be treated with the cognitive-enhancing medications, the cholinesterase inhibitors and memantine. For most of the common causes of dementia, there are no disease-modifying medications, with the exception that vascular dementia can be prevented by treating vascular risk factors to prevent stroke. There is hope that Alzheimer disease can be treated by using monoclonal antibodies that target amyloid beta, although more trials are needed. Holistic, patient-centered care can enhance quality and extend the time that the patient can live safely in the community.

Indian Psychiatric Society multicentre study: Diagnostic patterns, comorbidity and prescription practices for patients with Dementia

BACKGROUND

There are more than 5 million people with dementia in India. Multicentre studies looking at details of treatment for people with dementia In India are lacking. Clinical audit is a quality improvement process which aims to systematically assess, evaluate, and improve patient care. Evaluating current practice is the key to a clinical audit cycle.

AIM

This study aimed to assess the diagnostic patterns and prescribing practices of psychiatrists for patients with dementia in India.

METHOD

A retrospective case file study was conducted across several centers in India.

RESULTS

Information from the case records of 586 patients with dementia was obtained. Mean age of the patients was 71.14 years (standard deviation = 9.42). Three hundred twenty one (54.8%) were men. Alzheimer's disease (349; 59.6%) was the most frequent diagnosis followed by vascular dementia (117; 20%). Three hundred fifty five (60.6%) patients had medical disorders and 47.4% patients were taking medications for their medical conditions. Eighty one (69.2%) patients with vascular dementia had cardiovascular problems. Majority of the patients (524; 89.4%) were on medications for dementia. Most frequently prescribed treatment was Donepezil (230; 39.2%) followed by Donepezil-Memantine combination (225; 38.4%). Overall, 380 (64.8%) patients were on antipsychotics. Quetiapine (213, 36.3%) was the most frequently used antipsychotic. Overall, 113 (19.3%) patients were on antidepressants, 80 (13.7%) patients were on sedatives/hypnotics, and 16 (2.7%) patients were on mood stabilizers. Three hundred nineteen (55.4%) patients and caregivers of 374 (65%) patients were receiving psychosocial interventions.

CONCLUSIONS

Diagnostic and prescription patterns in dementia which emerged from this study are comparable to other studies both nationally and internationally. Comparing current practices at individual and national levels against accepted guidelines, obtaining feedback, identifying gaps and instituting remedial measures help to improve the standard of care provided.

Efficacy of pharmacotherapy and non-pharmacotherapy of Alzheimer dementia: A protocol for systematic review and meta-analysis

BACKGROUND

Alzheimer disease (AD) is the most common cause of dementia worldwide. Despite the publication of numerous systematic reviews and meta-analyses that have summarized the evidence associated with pharmacotherapies (PTs) and non-pharmacotherapies (NPTs) for the wide range of interventions available for AD treatment, their comparative safety and efficacy remains insufficiently defined.

METHODS

Systematic reviews of randomized controlled trials (RCTs) will be selected according to the following criteria: conducted in elderly patients aged 60 years or older with AD living in community or institutionalized settings, applied pairwise meta-analysis (PMA) or network meta-analysis (NMA) approaches providing pooled relative treatment effects for at least 1 pair of PTs or NPTs, and providing at least 1 of the following outcomes for patients/caregivers: cognitive, functional status, behavior, quality of life (QoL), and caregiver stress or burden. All article screening, data extraction, and risk of bias assessment will be completed independently by 2 reviewers. Relative treatment rankings will be reported with mean ranks and surface under the cumulative ranking curves.

RESULTS AND CONCLUSION

We will determine the most efficacious treatment strategies for AD patients from the most highly ranked treatments. These results will help to guide clinical decision-making and improve patient care.

Pharmacotherapy of Alzheimer's disease: an overview of systematic reviews

BACKGROUND

Alzheimer's disease (AD) is a neurodegenerative disease and the most common cause of dementia. In this umbrella systematic review (SR), we summarized the efficacy of different pharmacological interventions in improving cognitive function in patients with AD.

METHODS

A systematic search was performed through the PubMed, Scopus, Embase, and Cochrane databases for SRs of studies assessing the efficacy of pharmacological interventions versus placebo in improving cognitive function in AD or mild cognitive impairment due to AD. The risk of bias (RoB) was assessed using the Risk of Bias in SRs (ROBIS) tool.

RESULTS

Out of 1748 articles found through the database survey, 33 SR articles were included. These studies assessed effects of immunotherapy, cholinesterase inhibitors (ChEIs), memantine, statins, lithium, nonsteroidal anti-inflammatory drugs (NSAIDs), antidiabetic agents, Cerebrolysin, RAS-targeting antihypertensive drugs (ARBs and ACEIs), psychostimulants, glycogen synthase kinase 3 (GSK-3) inhibitors, melatonin, and herbal medications on cognitive function in AD patients. There was no notable overall RoB in 18 studies (54.5%), the RoB in 14 studies (42.4%) was high, and in one study (3.0%) it was unclear.

CONCLUSIONS

The use of ChEIs, including rivastigmine, galantamine, and donepezil, as well as memantine has demonstrated a positive impact on improving cognitive outcomes of AD patients, but no considerable effects were found for immunotherapies. Melatonin, statins, antihypertensive drugs, antidiabetic agents, Cerebrolysin, psychostimulants, and some herbal drugs such as Danggui-Shaoyao-San and Ginkgo biloba seem to be effective in improving cognitive function of AD patients, but the evidence in this regard is limited.

Alzheimer's Disease: Efficacy of Mono- and Combination Therapy. A Systematic Review

IMPORTANCE

Alzheimer's disease (AD) is a complex neurodegenerative disorder and the most prevalent cause of dementia. In spite of the urgent need for more effective AD drug therapy strategies, evidence of the efficacy of combination therapy with existing drugs remains unclear.

OBJECTIVE

To assess the efficacy of combined drug therapy on cognition and progress in patients with AD in comparison to single agent drug therapy.

METHODS

The electronic databases MEDLINE and EMBASE were systematically searched to identify relevant publications. Only randomized controlled clinical trials were included, but no limits were applied to language or time published. Data were extracted from May 27th until December 29th, 2020.

RESULTS

Three trials found that a combination of ChEI with additional memantine provides a slight benefit for patients with moderate to severe AD over ChEI monotherapy and placebo. However, a further 4 trials could not replicate this effect. One trial reported benefits of add-on Gingko biloba in donepezil-treated patients with moderate AD (using a formula containing Gingko and other antioxidants) compared to donepezil with placebo. A further trial found no significant effect of combining EGb 761® and donepezil in patients with probable AD over donepezil with placebo. Approaches with idalopirdine, atorvastatin or vitamin supplementation in combination with ChEI have not proven effective and have not been retried since. Fluoxetine and ST101 have shown partial benefits in combination with ChEI over ChEI monotherapy and placebo. However, these effects must be replicated by further research.

CONCLUSION

Additional memantine in combination with ChEI might be of slight benefit in patients with moderate to severe AD, but evidence is ambiguous. Longer trials are needed. No major cognitive benefit is missed, if solely appropriate ChEI monotherapy is initiated.

Bioavailability Study of a Transdermal Patch Formulation of Rivastigmine Compared with Exelon in Healthy Subjects

BACKGROUND AND OBJECTIVES

Rivastigmine is a reversible cholinesterase inhibitor indicated for the treatment of all stages of Alzheimer's disease (AD). Transdermal patch formulation allows smooth and continuous drug delivery. Its tolerability, efficacy and convenience of use increase treatment compliance. This study was designed to evaluate the bioavailability and to assess the bioequivalence of two rivastigmine transdermal patches at steady state (RIV-TDS Test Product versus Exelon Marketed Reference Product), with a release rate of 13.3 mg/24 h, after multiple patch applications. As secondary objectives, safety, patch adhesion and skin irritation were evaluated.

METHODS

This was an open-label, randomized, balanced, two-period, two-sequence, cross-over study of healthy adults (n = 31). The treatment period consisted of two 5-day study periods during which consecutive daily application of the investigational patches with a release rate of 13.3 mg/24 h rivastigmine took place. Serial blood samples were collected to measure plasma concentrations. Adhesion and skin irritation assessments were performed after application of patches.

RESULTS

Point estimates and 90% confidence intervals of pharmacokinetic parameters at steady state, viz. area under the plasma concentration versus time curve from dosing time to the end of the dosing interval τ (profile day) at steady state [AUC_0-τ,ss] (97.4; 88.8-106.9), maximum plasma concentration within the dosing interval τ (profile day) at steady state [C_max,ss] (99.6; 90.4-109.7) and trough plasma concentration at the end of the dosing interval τ (profile day) at steady state [C_τ,ss] (96.8; 86.2-108.9), demonstrated that both patches were bioequivalent. Evaluation of patch adhesion showed better skin adherence for RIV-TDS as well as dermal response scores (skin tolerability after removal).

CONCLUSIONS

For both products, bioequivalence was shown and systemic tolerability was in accordance with the safety profile of the drug substance. The trial is registered in ClinicalTrials.gov: NCT03573050 and EudraCT: 2018-000968-28.

The Efficacy and Safety of Alzheimer's Disease Therapies: An Updated Umbrella Review

BACKGROUND

Evidence summaries for efficacy and safety of frequently employed treatments of Alzheimer's disease (AD) are sparse.

OBJECTIVE

We aimed to perform an updated umbrella review to identify an efficacious and safe treatment for AD patients.

METHODS

We conducted a search for meta-analyses and systematic reviews on the Embase, PubMed, The Cochrane Library, and Web of Science to address this knowledge gap. We examined the cognitive functions, behavioral symptoms, global clinical assessment, and Activities of Daily Living as efficacy endpoints, and the incidence of adverse events as safety profiles.

RESULTS

Sixteen eligible papers including 149 studies were included in the umbrella review. The results showed that AChE inhibitors (donepezil, galantamine, rivastigmine, Huperzine A), Ginkgo biloba, and cerebrolysin appear to be beneficial for cognitive, global performances, and activities of daily living in patients with AD. Furthermore, anti-Aβ agents are unlikely to have an important effect on slowing cognitive or functional impairment in mild to moderate AD.

CONCLUSION

Our study demonstrated that AChE inhibitors, Ginkgo biloba, and cerebrolysin are the optimum cognitive and activities of daily living medication for patients with AD.

Exercise priming with transcranial direct current stimulation: a study protocol for a randomized, parallel-design, sham-controlled trial in mild cognitive impairment and Alzheimer's disease

Background

Transcranial direct current stimulation (tDCS) is a non-invasive type of brain stimulation that uses electrical currents to modulate neuronal activity. A small number of studies have investigated the effects of tDCS on cognition in patients with Mild Cognitive Impairment (MCI) and Alzheimer’s disease (AD), and have demonstrated variable effects. Emerging evidence suggests that tDCS is most effective when applied to active brain circuits. Aerobic exercise is known to increase cortical excitability and improve brain network connectivity. Exercise may therefore be an effective, yet previously unexplored primer for tDCS to improve cognition in MCI and mild AD.

Methods

Participants with MCI or AD will be randomized to receive 10 sessions over 2 weeks of either exercise primed tDCS, exercise primed sham tDCS, or tDCS alone in a blinded, parallel-design trial. Those randomized to an exercise intervention will receive individualized 30-min aerobic exercise prescriptions to achieve a moderate-intensity dosage, equivalent to the ventilatory anaerobic threshold determined by cardiopulmonary assessment, to sufficiently increase cortical excitability. The tDCS protocol consists of 20 min sessions at 2 mA, 5 times per week for 2 weeks applied through 35 cm² bitemporal electrodes. Our primary aim is to assess the efficacy of exercise primed tDCS for improving global cognition using the Montreal Cognitive Assessment (MoCA). Our secondary aims are to evaluate the efficacy of exercise primed tDCS for improving specific cognitive domains using various cognitive tests (n-back, Word Recall and Word Recognition Tasks from the Alzheimer’s Disease Assessment Scale-Cognitive subscale) and neuropsychiatric symptoms (Neuropsychiatric Inventory). We will also explore whether exercise primed tDCS is associated with an increase in markers of neurogenesis, oxidative stress and angiogenesis, and if changes in these markers are correlated with cognitive improvement.

Discussion

We describe a novel clinical trial to investigate the effects of exercise priming before tDCS in patients with MCI or mild AD. This proof-of-concept study may identify a previously unexplored, non-invasive, non-pharmacological combination intervention that improves cognitive symptoms in patients. Findings from this study may also identify potential mechanistic actions of tDCS in MCI and mild AD.

Trial registration

Clinicaltrials.gov, NCT03670615. Registered on September 13, 2018.

Efficacy of Acetylcholinesterase Inhibitors on Cognitive Function in Alzheimer's Disease. Review of Reviews

Alzheimer’s disease (AD) is the most common form of dementia over the age of 65. It is estimated that 115.4 million people will be affected by AD by 2050. Acetylcholinesterase inhibitors (AChEI) are the only available and approved treatment for AD. The aim of the present study was to analyse the evidence on the efficacy of the AChEI in the treatment of cognitive symptoms of Alzheimer’s disease. For that purpose, a review of review of the systematic reviews (SRs) on this topic was carried out by Web of Science, PubMed, and The Cochrane Library, among others, were searched until 24 September 2021. Thirteen of the 1773 articles evaluated the efficacy of AChEI on cognitive function and/or general condition and/or behavioural disturbances of patients with mild to moderate AD. Methodological quality and risk of bias were rated using the ROBIS scale. The quality of the identified studies was high for nine of them, unclear for two, and finally only in two of the 13 studies did we detect low quality. Overall, AChEI showed very low efficacy in improving cognition in patients with mild to moderate AD. Better results were obtained in improving global state, with donepezil being the most effective treatment. No improvements in behavioural disturbances were found. Few high-quality reviews provide clear evidence of the effects of AChEI on cognition, global change, behaviour, and mortality. The data suggest that AChEI stabilize or slow cognitive deterioration, improving global status. In addition, data indicate that the use of AChEI decreases mortality in patients with mild to moderate AD. However, there is no evidence that they improve patient behaviour. Donepezil is the best therapeutic alternative at a dose of 10 mg/day.

Design, synthesis and biological evaluation of naringenin carbamate derivatives as potential multifunctional agents for the treatment of Alzheimer's disease

A series of naringenin derivatives were designed and synthesized as multifunctional anti-Alzheimer's disease (AD) agents. The results showed that these derivatives displayed moderate-to-good acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activities at the micromolar range (IC₅₀, 12.91 ~ 62.52 μM for AChE and 0.094 ~ 13.72 μM for BuChE). Specifically, compound 1 showed the highest inhibitory activity against BuChE with the IC₅₀ value of (0.094 ± 0.0054) μM. A Lineweaver-Burk plot and molecular docking studies demonstrated that 1 targeted both the catalytically active site (CAS) and the peripheral anion site (PAS) of BuChE. Besides, all derivatives showed excellent hydroxyl free radicals (·OH) scavenging ability than vitamin C and cyclic voltammetry results displayed that 1 could effectively scavenge superoxide anion radical (·O₂^-). In addition, compound 1 displayed good metal chelating properties and had anti-Aβ aggregation activities. Therefore, compound 1 might be the potential anti-AD agent for further developments.

Effects of New Galantamine Derivatives in a Scopolamine Model of Dementia in Mice

Alzheimer's disease (AD), a progressive neurodegenerative disorder characterized by memory loss and cognitive functions decline, is a leading cause for dementia and currently ranked as the sixth foremost cause of death. As of present, treatment of AD is symptomatic without convincing therapeutic benefits and new, effective, therapeutic agents are pursued. Due to massive loss of cholinergic neurons and decreased acetylcholine levels, cholinesterase inhibitors like galantamine, remain the backbone of pharmacological treatment of the disease. In the present study, using behavioral and biochemical methods, four newly synthesized galantamine derivatives, Gal 34, Gal 43, Gal 44, and Gal 46, were evaluated for a beneficial effect in a scopolamine model of dementia in mice. They were designed to have all the advantages of galantamine and additionally to inhibit β-secretase and exert favorable effects on plasma lipids. Behavioral tests included step-through inhibitory avoidance, T-maze, and the hole-board test, whereas biochemical evaluations involved assessment of acetylcholinesterase activity, brain monoamines levels, lipid peroxidation, catalase, glutathione peroxidase, and superoxide dismutase activities along with measurement of total glutathione. Results show that Gal 43, Gal 44, and, in particular, Gal 46 are especially effective in improving both short- and long-term memory and in the case of Gal 46 having a significant effect on exploratory activity as well. Although Gal 34 did not show behavioral effects as convincing as those of the other three galantamine derivatives, it demonstrated persuasive antioxidant and restorative capacities, making all four galantamine derivatives promising AD treatment agents and prompting further research, especially that in many of our studies they performed better than galantamine.

Recent Updates in the Alzheimer's Disease Etiopathology and Possible Treatment Approaches: A Narrative Review of Current Clinical Trials

BACKGROUND

Alzheimer's disease (AD) is the most frequent subtype of incurable neurodegenerative dementias and its etiopathology is still not clearly elucidated.

OBJECTIVE

Outline the ongoing clinical trials (CTs) in the field of AD, in order to find novel master regulators.

METHODS

We strictly reviewed all scientific reports from Clinicaltrials.gov and PubMed databases from January 2010 to January 2019. The search terms were "Alzheimer's disease" or "dementia" and "medicine" or "drug" or "treatment" and "clinical trials" and "interventions". Manuscripts that met the objective of this study were included for further evaluations.

RESULTS

Drug candidates have been categorized into two main groups including antibodies, peptides or hormones (such as Ponezumab, Interferon β-1a, Solanezumab, Filgrastim, Levemir, Apidra, and Estrogen), and naturally-derived ingredients or small molecules (such as Paracetamol, Ginkgo, Escitalopram, Simvastatin, Cilostazo, and Ritalin-SR). The majority of natural candidates acted as anti-inflammatory or/and anti-oxidant and antibodies exert their actions via increasing amyloid-beta (Aβ) clearance or decreasing Tau aggregation. Among small molecules, most of them that are present in the last phases act as specific antagonists (Suvorexant, Idalopirdine, Intepirdine, Trazodone, Carvedilol, and Risperidone) or agonists (Dextromethorphan, Resveratrol, Brexpiprazole) and frequently ameliorate cognitive dysfunctions.

CONCLUSION

The presences of a small number of candidates in the last phase suggest that a large number of candidates have had an undesirable side effect or were unable to pass essential eligibility for future phases. Among successful treatment approaches, clearance of Aβ, recovery of cognitive deficits, and control of acute neuroinflammation are widely chosen. It is predicted that some FDA-approved drugs, such as Paracetamol, Risperidone, Escitalopram, Simvastatin, Cilostazoand, and Ritalin-SR, could also be used in off-label ways for AD. This review improves our ability to recognize novel treatments for AD and suggests approaches for the clinical trial design for this devastating disease in the near future.

Antimuscarinic Cascade Across Individual Cholinesterase Inhibitors in Older Adults with Dementia

BACKGROUND

Acetylcholinesterase inhibitors (AChEIs) have been associated with an increased risk of starting antimuscarinic treatment to treat overactive bladder (OAB)-an example of a prescribing cascade. Limited comparative data exist regarding the prescribing cascade of antimuscarinics across individual AChEIs in older adults with dementia.

OBJECTIVE

This study examined the association between individual AChEI use and antimuscarinic cascade in older adults with dementia.

METHODS

We conducted a new user retrospective cohort study from January 2005 to December 2018 using data from the TriNetX electronic medical record database, a federated electronic medical records network in the US. The cohort included patients 65 years or older with a diagnosis of dementia using AChEIs (donepezil, galantamine, or rivastigmine). Individual AChEIs were identified with index dates from 1 January 2006 to 31 June 2018, with a 1-year washout period. The study excluded patients with any antimuscarinic use and OAB diagnosis 1 year before the AChEI index date. The primary outcome of interest was the prescription of antimuscarinics within 6 months of the AChEI index date. A Cox proportional hazard model was used to assess the association between individual incident AChEI use and antimuscarinic prescribing cascade after controlling for several covariates.

RESULTS

The study included 47,059 older adults with dementia who were incident users of AChEIs. Most of these patients were initiated with donepezil (83.1%), followed by rivastigmine (12.3%) and galantamine (4.6%). Overall, 8.16% of the study cohort had incident OAB diagnosis or antimuscarinic prescription. Antimuscarinics were initiated by 1725 (3.7%) older adults with dementia within 6 months of AChEI prescription, and cascade varied widely across individual agents-donepezil (3.9%), rivastigmine (2.6%), and galantamine (2.9%). Cox proportional hazard analyses revealed that donepezil users had an increased risk of receiving antimuscarinics (adjusted hazard ratio 1.55, 95% confidence interval 1.31-1.83) compared with rivastigmine. The findings were consistent in sensitivity analyses.

CONCLUSION

This study found that donepezil use is more likely to lead to antimuscarinic cascade than rivastigmine. Future studies are needed to determine the potential consequences of this cascade in dementia.

Use of psychotropic agents to treat agitation and aggression in Brazilian patients with Alzheimer's disease: A naturalistic and multicenter study

We assessed psychotropic prescribing patterns in the clinical treatment of agitation and aggressive behavior in patients with Alzheimer's disease (AD) treated at specialist outpatient clinics in the Federal District of Brazil. This was a naturalistic, observational, multicenter study of a convenience sample of patients with AD (according to DSM-5) who had behavioral symptoms of aggression and/or agitation at outpatient visits, as assessed by the Neuropsychiatric Inventory (NPI), and required pharmacologic intervention. Participants were recruited in 2018-2019 from 11 AD treatment centers. Sociodemographic and clinical data were collected during routine visits. The sample consisted of 369 older adults with a mean age of 82.3 (SD, 7.7) years. The medications most commonly used in patients with behavioral disorders were antidepressants (79.1%), antipsychotics (70.2%), benzodiazepines (10.6%), and mood stabilizers (9.5%). Quetiapine was the most frequently prescribed antipsychotic medication (48.5%), at a mean dose of 57.4 (SD, 40.7) mg. Citalopram was the most widely used antidepressant medication (32.0%), at a mean daily dose of 24.1 (SD, 8.1) mg. In this sample, two or more pharmacologic agents were frequently used together to control aggression and agitation. Benzodiazepine was not frequently used.

Indian Medicinal Herbs and Formulations for Alzheimer's Disease, from Traditional Knowledge to Scientific Assessment

Cognitive impairment, associated with ageing, stress, hypertension and various neurodegenerative disorders including Parkinson's disease and epilepsy, is a major health issue. The present review focuses on Alzheimer's disease (AD), since it is the most important cause of cognitive impairment. It is characterized by progressive memory loss, language deficits, depression, agitation, mood disturbances and psychosis. Although the hallmarks of AD are cholinergic dysfunction, β-amyloid plaques and neurofibrillary tangle formation, it is also associated with derangement of other neurotransmitters, elevated levels of advanced glycation end products, oxidative damage, neuroinflammation, genetic and environmental factors. On one hand, this complex etiopathology makes a response to commonly used drugs such as donepezil, rivastigmine, galantamine and memantine less predictable and often unsatisfactory. On the other hand, it supports the use of herbal medicines due to their nonspecific antioxidant and anti-inflammatory activity and specific cholinesterase inhibitory activity. The popularity of herbal medicines is also increasing due to their perceived effectiveness, safety and affordability. In the present article, the experimental and clinical evidence have been reviewed for various Indian herbal medicines such as Centella asiatica, Bacopa monnieri, Curcuma longa, Clitoria ternatea, Withania somnifera, Celastrus paniculatus, Evolvulus alsinoides, Desmodium gangeticum, Eclipta alba, Moringa oleifera and Convolvulus pluricaulis, which have shown potential in cognitive impairment. Some commonly available herbal formulations for memory impairment in India have also been reviewed.

Pharmacotherapy of Behavioral and Psychological Symptoms of Dementia: State of the Art and Future Progress

The core symptoms of different dementia subtypes are the behavioral and psychological symptoms of dementia (BPSD) and its neuropsychiatric symptoms (NPS). BPSD symptoms may occur at any stage in the case of dementia due to Alzheimer's disease (AD), whereas they tend to occur early on in the case of its behavioral variant frontotemporal dementia or dementia with Lewy bodies and are essential for diagnosis. BPSD treatment consists of non-pharmacological as well as pharmacological interventions, with non-pharmacological interactions being suggested as first-line treatment. Agitation, psychotic features, apathy, depression, and anxiety may not respond to acetylcholinesterase inhibitors or memantine in AD cases; therefore, antipsychotics, antidepressants, sedative drugs or anxiolytics, and antiepileptic drugs are typically prescribed. However, such management of BPSD can be complicated by hypersensitivity to antipsychotic drugs, as observed in DLB, and a lack of effective pro-cognitive treatment in the case of frontotemporal dementia. The present paper reviews current knowledge of the management of BPSD and its limitations and discusses on-going clinical trials and future therapeutic options.

Cholinesterase Inhibitors for Alzheimer's Disease: Multitargeting Strategy Based on Anti-Alzheimer's Drugs Repositioning

In the brain, acetylcholine (ACh) is regarded as one of the major neurotransmitters. During the advancement of Alzheimer's disease (AD) cholinergic deficits occur and this can lead to extensive cognitive dysfunction and decline. Acetylcholinesterase (AChE) remains a highly feasible target for the symptomatic improvement of AD. Acetylcholinesterase (AChE) remains a highly viable target for the symptomatic improvement in AD because cholinergic deficit is a consistent and early finding in AD. The treatment approach of inhibiting peripheral AChE for myasthenia gravis had effectively proven that AChE inhibition was a reachable therapeutic target. Subsequently tacrine, donepezil, rivastigmine, and galantamine were developed and approved for the symptomatic treatment of AD. Since then, multiple cholinesterase inhibitors (ChEIs) have been continued to be developed. These include newer ChEIs, naturally derived ChEIs, hybrids, and synthetic analogues. In this paper, we summarize the different types of ChEIs which are under development and their respective mechanisms of actions.

Effectiveness and Safety of Acupuncture for the Treatment of Alzheimer's Disease: A Systematic Review and Meta-Analysis

Background: The effects of acupuncture on Alzheimer's disease (AD) outcomes remain controversial. The aim of this review was to evaluate the effectiveness and safety of acupuncture for the treatment of AD.

Methods: PubMed, Embase, Web of Science, the Cochrane Central Register of Controlled Trials, Chinese BioMedical Literature Database, VIP Database for Chinese Technical Periodicals, China National Knowledge Infrastructure, and Wanfang Data were searched to identify relevant randomized controlled trials from inception to January 19, 2019. Data were extracted and evaluated by two authors independently. The data analysis was conducted using R (version 3.6.0) and RStudio (version 1.2.1335) software.

Results: Thirty trials involving 2,045 patients were included. Acupuncture plus drug therapy may have been more beneficial for general cognitive function in AD patients than drug therapy alone (short-term treatment: MD, mean difference = 1.94, 95% CI: 1.11, 2.77; p < 0.01; medium-term treatment: MD = 4.41, 95% CI: 1.83, 7.00; p < 0.01). People who received acupuncture plus drug therapy attained higher ADL (Activities of Daily Living) scores than patients who received drug therapy alone for medium-term treatment duration (MD = −2.14; 95% CI: −3.69, −0.59; p < 0.01). However, there is no statistically significant difference in subgroup effect on MMSE (Mini-mental Status Examination) and ADLs (p > 0.05) when comparing acupuncture treatment with drug therapy (such as Donepezil hydrochloride, Nimodipine, or Yizhijiannao), or acupuncture plus drug therapy (such as Donepezil hydrochloride, Dangguishaoyaosan, or Jiannaosan) with drug therapy alone. There was also no significant difference in general cognitive function, ADLs, or incidence of adverse events between acupuncture treatment and drug therapy (p > 0.05).

Conclusions: This review indicates that acupuncture plus drug therapy may have a more beneficial effect for AD patients than drug therapy alone on general cognitive function in the short and medium term and on ADLs in the medium term. Acupuncture alone may not have superior effects compared with drug therapy on global cognitive function, ADLs, and incidence of adverse events. Duration of treatment may not modify the effect of acupuncture in comparison with drug therapy. Additional large-scale and high-quality clinical trials are needed.

Bupropion for the Treatment of Apathy in Alzheimer Disease: A Randomized Clinical Trial

IMPORTANCE

Apathy is a frequent neuropsychiatric symptom in dementia of Alzheimer type and negatively affects the disease course and patients' and caregivers' quality of life. Effective treatment options are needed.

OBJECTIVE

To examine the efficacy and safety of the dopamine and noradrenaline reuptake inhibitor bupropion in the treatment of apathy in patients with dementia of Alzheimer type.

DESIGN, SETTING, AND PARTICIPANTS

This 12-week, multicenter, double-blind, placebo-controlled, randomized clinical trial was conducted in a psychiatric and neurological outpatient setting between July 2010 and July 2014 in Germany. Patients with mild-to-moderate dementia of Alzheimer type and clinically relevant apathy were included. Patients with additional clinically relevant depressed mood were excluded. Data analyses were performed between August 2018 and August 2019.

INTERVENTIONS

Patients received either bupropion or placebo (150 mg for 4 weeks plus 300 mg for 8 weeks). In case of intolerability of 300 mg, patients continued to receive 150 mg throughout the study.

MAIN OUTCOMES AND MEASURES

Change on the Apathy Evaluation Scale-Clinician Version (AES-C) (score range, 18-72 points) between baseline and week 12 was the primary outcome parameter. Secondary outcome parameters included measures of neuropsychiatric symptoms, cognition, activities of daily living, and quality of life. Outcome measures were assessed at baseline and at 4, 8, and 12 weeks.

RESULTS

A total of 108 patients (mean [SD] age, 74.8 [5.9] years; 67 men [62%]) were included in the intention-to-treat analysis, with 54 randomized to receive bupropion and 54 randomized to receive placebo. The baseline AES-C score was comparable between the bupropion group and the placebo group (mean [SD], 52.2 [8.7] vs 50.4 [8.2]). After controlling for the baseline AES-C score, site, and comedication with donepezil or galantamine, the mean change in the AES-C score between the bupropion and placebo groups was not statistically significant (mean change, 2.22; 95% CI, -0.47 to 4.91; P = .11). Results on secondary outcomes showed statistically significant differences between bupropion and placebo in terms of total neuropsychiatric symptoms (mean change, 5.52; 95% CI, 2.00 to 9.04; P = .003) and health-related quality of life (uncorrected for multiple comparisons; mean change, -1.66; 95% CI, -3.01 to -0.31; P = .02) with greater improvement in the placebo group. No statistically significant changes between groups were found for activities of daily living (mean change, -2.92; 95% CI, -5.89 to 0.06; P = .05) and cognition (mean change, -0.27; 95% CI, -3.26 to 2.73; P = .86). The numbers of adverse events (bupropion group, 39 patients [72.2%]; placebo group, 33 patients [61.1%]) and serious adverse events (bupropion group, 5 patients [9.3%]; placebo group, 2 patients [3.7%]) were comparable between groups.

CONCLUSIONS AND RELEVANCE

Although it is safe, bupropion was not superior to placebo for the treatment of apathy in patients with dementia of Alzheimer type in the absence of clinically relevant depressed mood.

TRIAL REGISTRATION

EU Clinical Trials Register Identifier: 2007-005352-17.

Rivastigmine modifies the α-secretase pathway and potentially early Alzheimer's disease

Rivastigmine (or Exelon) is a cholinesterase inhibitor, currently used as a symptomatic treatment for mild-to-moderate Alzheimer's disease (AD). Amyloid-β peptide (Aβ) generated from its precursor protein (APP) by β-secretase (or BACE1) and γ-secretase endoproteolysis. Alternative APP cleavage by α-secretase (a family of membrane-bound metalloproteases- Adamalysins) precludes the generation of toxic Aβ and yields a neuroprotective and neurotrophic secreted sAPPα fragment. Several signal transduction pathways, including protein kinase C and MAP kinase, stimulate α-secretase. We present data to suggest that rivastigmine, in addition to anticholinesterase activity, directs APP processing away from BACE1 and towards α-secretases. We treated rat neuronal PC12 cells and primary human brain (PHB) cultures with rivastigmine and the α-secretase inhibitor TAPI and assayed for levels of APP processing products and α-secretases. We subsequently treated 3×Tg (transgenic) mice with rivastigmine and harvested hippocampi to assay for levels of APP processing products. We also assayed postmortem human control, AD, and AD brains from subjects treated with rivastigmine for levels of APP metabolites. Rivastigmine dose-dependently promoted α-secretase activity by upregulating levels of ADAM-9, -10, and -17 α-secretases in PHB cultures. Co-treatment with TAPI eliminated rivastigmine-induced sAPPα elevation. Rivastigmine treatment elevated levels of sAPPα in 3×Tg mice. Consistent with these results, we also found elevated sAPPα in postmortem brain samples from AD patients treated with rivastigmine. Rivastigmine can modify the levels of several shedding proteins and directs APP processing toward the non-amyloidogenic pathway. This novel property of rivastigmine can be therapeutically exploited for disease-modifying intervention that goes beyond symptomatic treatment for AD.

Do Acetylcholinesterase Inhibitors Prevent or Delay Psychotropic Prescribing in People With Dementia? Analyses of the Swedish Dementia Registry

OBJECTIVES

To investigate whether acetylcholinesterase inhibitor (AChEI) use prevents or delays subsequent initiation of psychotropic medications in people with Alzheimer's disease (AD) and Lewy body dementia (LBD).

METHODS

Cohort study of 17,763 people with AD and LBD, without prior psychotropic use at time of dementia diagnosis, registered in the Swedish Dementia Registry from 2007 to 2015. Propensity score-matched regression models were used to compute hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between time-dependent AChEI use and risk of psychotropic initiation.

RESULTS

Compared with matched comparators, AChEI users had a lower risk of antipsychotic (HR: 0.85, 95%CI: 0.75-0.95) and anxiolytic (HR: 0.76, 95%CI: 0.72-0.80) initiation. In subanalyses, this association remained significant at higher AChEI doses, and in AD but not LBD. There were no associations between AChEI use and initiation of antidepressants or hypnotics.

CONCLUSION

AChEI use may be associated with lower risk of antipsychotic and anxiolytic initiation in AD, particularly at higher doses. Further investigation into aceytylcholinesterase inhibitors in behavioral and psychological symptoms of dementia management in LBD is warranted.

Potential therapeutic roles of retinoids for prevention of neuroinflammation and neurodegeneration in Alzheimer's disease

All retinoids, which can be natural and synthetic, are chemically related to vitamin A. Both natural and synthetic retinoids use specific nuclear receptors such as retinoic acid receptors and retinoid X receptors to activate specific signaling pathways in the cells. Retinoic acid signaling is extremely important in the central nervous system. Impairment of retinoic acid signaling pathways causes severe pathological processes in the central nervous system, especially in the adult brain. Retinoids have major roles in neural patterning, differentiation, axon outgrowth in normal development, and function of the brain. Impaired retinoic acid signaling results in neuroinflammation, oxidative stress, mitochondrial malfunction, and neurodegeneration leading to progressive Alzheimer's disease, which is pathologically characterized by extra-neuronal accumulation of amyloid plaques (aggregated amyloid-beta) and intra-neurofibrillary tangles (hyperphosphorylated tau protein) in the temporal lobe of the brain. Alzheimer's disease is the most common cause of dementia and loss of memory in old adults. Inactive cholinergic neurotransmission is responsible for cognitive deficits in Alzheimer's disease patients. Deficiency or deprivation of retinoic acid in mice is associated with loss of spatial learning and memory. Retinoids inhibit expression of chemokines and neuroinflammatory cytokines in microglia and astrocytes, which are activated in Alzheimer's disease. Stimulation of retinoic acid receptors and retinoid X receptors slows down accumulation of amyloids, reduces neurodegeneration, and thereby prevents pathogenesis of Alzheimer's disease in mice. In this review, we described chemistry and biochemistry of some natural and synthetic retinoids and potentials of retinoids for prevention of neuroinflammation and neurodegeneration in Alzheimer's disease.

Ginkgo biloba Extract (EGb761), Cholinesterase Inhibitors, and Memantine for the Treatment of Mild-to-Moderate Alzheimer's Disease: A Network Meta-Analysis

BACKGROUND

Cholinesterase inhibitors (ChEIs) and memantine have been reported to provide modest benefits for cognition and aspects of functioning in Alzheimer's disease (AD). Ginkgo biloba extract (EGb761), a phytomedicine, is widely used and expected to be well-tolerated. A few trials have compared EGb761 with ChEIs, and the results were inconclusive.

OBJECTIVE

A network meta-analysis was conducted to evaluate the therapeutic benefits and tolerability of EGb761, three ChEIs (donepezil, galantamine, and rivastigmine), and memantine in mild-to-moderate AD patients.

METHODS

Electronic databases were searched through 30 June 2017. We included randomized double-blinded trials with a minimum treatment duration of 22 weeks for EGb761 240 mg/day and 12 weeks for ChEIs or memantine. The study patients included AD or probable AD patients without other types of dementia or neurological disorders. Cognition, function, and behavior symptoms were compared between treatments using the standardized mean difference (SMD). Clinical global impression, treatment discontinuation, and adverse events were compared between treatments using the relative risk (RR). Statistical pooling of the individual trial results was conducted using a frequentist approach. The probability of being the best for a treatment was estimated using surface under the cumulative ranking.

RESULTS

EGb761 and memantine showed no therapeutic benefits in all study outcomes. For cognition, all ChEIs were significantly better than placebo (SMD from - 0.52 to - 0.26), and galantamine was better than rivastigmine in the oral and patch forms, EGb761, and memantine (SMD [95% confidence interval (CI)]: - 0.22 [- 0.40 to - 0.05]; - 0.26 [- 0.45 to - 0.07]; - 0.34 [- 0.56 to -  0.12]; and - 0.42 [- 0.71 to - 0.13], respectively). Compared to placebo, galantamine, the rivastigmine patch, and oral rivastigmine provided modest functional benefits (SMD, from 0.21 to 0.24), and galantamine provided behavioral benefits (SMD [95% CI]: - 0.15 [- 0.26 to - 0.04]). All ChEIs provided a better improvement in clinical global impression than placebo (RR from 1.20 to 1.69). The global impression ratings were more improved with donepezil than with galantamine (RR [95% CI]: 1.40 [1.09-1.80]) or with EGb761 (RR [95% CI]: 1.40 [1.06-1.85]), with a 96% probability of donepezil being more effective than the other study agents. Rivastigmine in oral and patch forms, galantamine, and donepezil had a higher risk of being discontinued than placebo (RR [95% CI]: 2.14 [1.49-3.06]; 2.04 [1.30-3.20]; 1.79 [1.28-2.49]; 1.49 [1.03-2.17], respectively). Discontinuation of EGb761 was not statistically lower than that of the ChEIs, in which donepezil had the lowest probability (38%) of being discontinued.

CONCLUSION

EGb761 and memantine showed no treatment benefits compared to placebo and ChEIs. Galantamine provided the highest beneficial effect on cognition and behavioral symptoms. Donepezil provided a better clinical global impression and tolerability than the other ChEIs and EGb761, with a similar benefit for cognition as galantamine.

The "rights" of precision drug development for Alzheimer's disease

There is a high rate of failure in Alzheimer's disease (AD) drug development with 99% of trials showing no drug-placebo difference. This low rate of success delays new treatments for patients and discourages investment in AD drug development. Studies across drug development programs in multiple disorders have identified important strategies for decreasing the risk and increasing the likelihood of success in drug development programs. These experiences provide guidance for the optimization of AD drug development. The "rights" of AD drug development include the right target, right drug, right biomarker, right participant, and right trial. The right target identifies the appropriate biologic process for an AD therapeutic intervention. The right drug must have well-understood pharmacokinetic and pharmacodynamic features, ability to penetrate the blood-brain barrier, efficacy demonstrated in animals, maximum tolerated dose established in phase I, and acceptable toxicity. The right biomarkers include participant selection biomarkers, target engagement biomarkers, biomarkers supportive of disease modification, and biomarkers for side effect monitoring. The right participant hinges on the identification of the phase of AD (preclinical, prodromal, dementia). Severity of disease and drug mechanism both have a role in defining the right participant. The right trial is a well-conducted trial with appropriate clinical and biomarker outcomes collected over an appropriate period of time, powered to detect a clinically meaningful drug-placebo difference, and anticipating variability introduced by globalization. We lack understanding of some critical aspects of disease biology and drug action that may affect the success of development programs even when the "rights" are adhered to. Attention to disciplined drug development will increase the likelihood of success, decrease the risks associated with AD drug development, enhance the ability to attract investment, and make it more likely that new therapies will become available to those with or vulnerable to the emergence of AD.

The Association Between Circulating Inflammatory Markers and the Progression of Alzheimer Disease in Norwegian Memory Clinic Patients With Mild Cognitive Impairment or Dementia

OBJECTIVE

Neuroinflammation may play an important role in the pathogenesis and progression of Alzheimer disease (AD). The aim of the present study was to detect whether increased inflammatory activity at baseline could predict cognitive and functional decline in patients with amnestic mild cognitive impairment (aMCI) or AD dementia after 2 years.

METHODS

Serum samples from 242 memory clinic patients with an aMCI (n=88) or AD dementia (n=154) were analyzed for C-reactive protein and for 14 other inflammatory markers [interleukin (IL)-1β, interleukin-1 receptor antagonist, IL-6, IL-10, IL-12p40, IL-17a, IL-18, IL-22, IL-33, tumor necrosis factor, cluster of differentiation 40 ligand, interferon-γ, chemokine ligand (CCL) 2, and CCL4] by bead-based multiplex immunoassay. Disease progression was measured by the annual increase in the Clinical Dementia Rating Scale Sum of Boxes (CDR-SB) and annual decrease in the score on the Mini-Mental State Examination (MMSE).

RESULTS

No association between increased levels of the inflammatory markers and change on the CDR-SB or MMSE score was found, but there was a significant difference in baseline IL-6 and interleukin-1 receptor antagonist levels between aMCI and AD dementia groups.

CONCLUSION

Increased levels of inflammatory markers were not associated with faster progression as measured by the annual change on the CDR-SB or MMSE score.

Efficacy, Safety, and Tolerability of Switching from Oral Cholinesterase Inhibitors to Rivastigmine Transdermal Patch with 1-Step Titration in Patients with Mild to Moderate Alzheimer's Disease: A 24-Week, Open-Label, Multicenter Study in Japan

Background

Few studies have investigated treatment options for patients with Alzheimer's disease (AD) showing a poor response to oral cholinesterase inhibitors (ChEIs) in Japan.

Objective

To investigate the efficacy and safety of switching from oral ChEIs to rivastigmine transdermal patch in patients with AD.

Methods

In this multicenter, open-label, phase IV study in outpatient clinics in Japan, patients with mild-moderate AD who had a poor response to or experienced difficulty in continuing donepezil or galantamine were switched to rivastigmine transdermal patch (5 cm²; loaded dose 9 mg, delivery rate 4.6 mg/24 h) with a 1-step titration in week 4 (10 cm²; loaded dose 18 mg, delivery rate 9.5 mg/24 h), which was continued for 4 weeks in the titration period and 16 weeks in a maintenance period. The primary endpoint was the change in Mini-Mental State Examination (MMSE) total score from baseline to week 24.

Results

A total of 118 patients were enrolled and switched to rivastigmine, of which 102 completed the 24-week study. The MMSE total score was essentially unchanged during the study, with a least-square mean change (SD) of −0.35 (2.64) at week 24 (p = 0.1750). Exploratory analysis with a mixed-effect model comparing changes in MMSE between the pre- and post-switch periods suggested that switching to rivastigmine prevented a worsening of MMSE. Application site skin reactions/irritations occurred in 30.5% of patients overall, in 22.0% in the 8-week titration period, and in 10.2% in the 16-week maintenance period.

Conclusion

Within-class switching from an oral ChEI to rivastigmine transdermal patch might be an efficacious and tolerable option for AD patients showing a poor or limited response to a prior oral ChEI.

Novel N-benzylpyridinium moiety linked to arylisoxazole derivatives as selective butyrylcholinesterase inhibitors: Synthesis, biological evaluation, and docking study

A novel series of N-benzylpyridinium moiety linked to arylisoxazole ring were designed, synthesized, and evaluated for their in vitro acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities. Synthesized compounds were classified into two series of 5a-i and 5j-q considering the position of positively charged nitrogen of pyridinium moiety (3- or 4- position, respectively) connected to isoxazole carboxamide group. Among the synthesized compounds, compound 5n from the second series of compounds possessing 2,4-dichloroaryl group connected to isoxazole ring was found to be the most potent AChE inhibitor (IC₅₀ = 5.96 µM) and compound 5j also from the same series of compounds containing phenyl group connected to isoxazole ring demonstrated the most promising inhibitory activity against BChE (IC₅₀ = 0.32 µM). Also, kinetic study demonstrated competitive inhibition mode for both AChE and BChE inhibitory activity. Docking study was also performed for those compounds and desired interactions with those active site amino acid residues were confirmed through hydrogen bonding as well as π-π and π-anion interactions. In addition, the most potent compounds were tested against BACE1 and their neuroprotectivity on Aβ-treated neurotoxicity in PC12 cells which depicted negligible activity. It should be noted that most of the synthesized compounds from both categories 5a-i and 5j-q showed a significant selectivity toward BChE. However, series 5j-q were more active toward AChE than series 5a-i.

Comparative efficacy and safety of cognitive enhancers for treating vascular cognitive impairment: systematic review and Bayesian network meta-analysis

OBJECTIVE

To assess and compare the clinical efficacy and safety of cognitive enhancers (donepezil, galantamine, rivastigmine, and memantine) on cognition, behavior, function, and global status in patients with vascular cognitive impairment.

DATA SOURCES

The initial literature search was performed with PubMed, EMBASE, the Cochrane Methodology Register, the Cochrane Central Register of Controlled Trials, and Cumulative Index to Nursing & Allied Health (CINAHL) from inception to January 2018 for studies regarding donepezil, galantamine, rivastigmine, and memantine for treatment of vascular cognitive impairment.

DATA SELECTION

Randomized controlled trials on donepezil, galantamine, rivastigmine, and memantine as monotherapy in the treatment of vascular cognitive impairment were included. A Bayesian network meta-analysis was conducted.

OUTCOME MEASURES

Efficacy was assessed by changes in scores of the Alzheimer's Disease Assessment Scale, cognitive subscale, Mini-Mental State Examination, Neuropsychiatric Inventory scores and Clinician's Interview-Based Impression of Change Scale Plus Caregiver's Input, Activities of Daily Living, the Clinical Dementia Rating scale. Safety was evaluated by mortality, total adverse events (TAEs), serious adverse events (SAEs), nausea, vomiting. diarrhea, or cerebrovascular accidents (CVAs).

RESULTS

After screening 1717 citations, 12 randomized controlled trials were included. Donepezil and rivastigmine (mean difference (e) = -0.77, 95% confidence interval (CI): 0.25-1.32; MD = 1.05, 95% CI: 0.18-1.79) were significantly more effective than placebo in reducing Mini-Mental State Examination scores. Donepezil, galantamine, and memantine (MD = -1.30, 95% CI: -2.27 to -0.42; MD = -1.67, 95% CI: -3.36 to -0.06; MD = -2.27, 95% CI: -3.91 to -0.53) showed superior benefits on the Alzheimer's Disease Assessment Scale-cognitive scores compared with placebo. Memantine (MD = 2.71, 95% CI: 1.05-7.29) improved global status (Clinician's Interview-Based Impression of Change Scale Plus Caregiver's Input) more than the placebo. Safety results revealed that donepezil 10 mg (odds ratio (OR) = 3.04, 95% CI: 1.86-5.41) contributed to higer risk of adverse events than placebo. Galantamine (OR = 5.64, 95% CI: 1.31-26.71) increased the risk of nausea. Rivastigmine (OR = 16.80, 95% CI: 1.78-319.26) increased the risk of vomiting. No agents displayed a significant risk of serious adverse events, mortality, cerebrovascular accidents, or diarrhea.

CONCLUSION

We found significant efficacy of donepezil, galantamine, and memantine on cognition. Memantine can provide significant efficacy in global status. They are all safe and well tolerated.

Attention Measures of Accuracy, Variability, and Fatigue Detect Early Response to Donepezil in Alzheimer's Disease: A Randomized, Double-blind, Placebo-Controlled Pilot Trial

OBJECTIVE

Donepezil is widely used to treat Alzheimer's disease (AD), but detecting early response remains challenging for clinicians. Acetylcholine is known to directly modulate attention, particularly under high cognitive conditions, but no studies to date test whether measures of attention under high load can detect early effects of donepezil. We hypothesized that load-dependent attention tasks are sensitive to short-term treatment effects of donepezil, while global and other domain-specific cognitive measures are not.

METHOD

This longitudinal, randomized, double-blind, placebo-controlled pilot trial (ClinicalTrials.gov Identifier: NCT03073876) evaluated 23 participants newly diagnosed with AD initiating de novo donepezil treatment (5 mg). After baseline assessment, participants were randomized into Drug (n = 12) or Placebo (n = 11) groups, and retested after approximately 6 weeks. Cognitive assessment included: (a) attention tasks (Foreperiod Effect, Attentional Blink, and Covert Orienting tasks) measuring processing speed, top-down accuracy, orienting, intra-individual variability, and fatigue; (b) global measures (Alzheimer's Disease Assessment Scale-Cognitive Subscale, Mini-Mental Status Examination, Dementia Rating Scale); and (c) domain-specific measures (memory, language, visuospatial, and executive function).

RESULTS

The Drug but not the Placebo group showed benefits of treatment at high-load measures by preserving top-down accuracy, improving intra-individual variability, and averting fatigue. In contrast, other global or cognitive domain-specific measures could not detect treatment effects over the same treatment interval.

CONCLUSIONS

The pilot-study suggests that attention measures targeting accuracy, variability, and fatigue under high-load conditions could be sensitive to short-term cholinergic treatment. Given the central role of acetylcholine in attentional function, load-dependent attentional measures may be valuable cognitive markers of early treatment response.

Identification of the optimal cognitive drugs among Alzheimer's disease: a Bayesian meta-analytic review

PURPOSE

The increasing prevalence of Alzheimer's disease (AD) demands more effective drugs, which are still unclear. The aim of this study is to compare the effectiveness of six drugs, such as donepezil, rivastigmine, galantamine, memantine, huperzine-A, and tacrine, in senior AD patients and identify the most effective one to improve patients' cognitive function.

METHODS

A system of search strategies was used to identify relevant studies including randomized controlled trials and clinical controlled trials evaluating the efficacy of six drugs in patients with AD. We updated relevant studies that were published before March 2018 as full-text articles. Using Bayesian network meta-analysis (NMA), we ranked cognitive ability objectively based on Mini-Mental State Examination (MMSE). Pairwise and NMAs were sequentially performed for the efficacy of drugs compared to each drug or control group through the trials included.

RESULTS

Among the 35 trials included, no obvious heterogeneity (I 2=0.0%, P=0.583) was revealed according to the pooled data for cognition in NMA and the mean difference (MD) of memantine (MD=1.7, 95% CI: 0.73, 2.8) showed that the memantine was significantly efficacious in the treatment group in terms of MMSE. Followed by galantamine, huperzine-A, rivastigmine, tacrine, and donepezil.

CONCLUSION

As the first NMA comparing the major drugs in market for AD, our study suggests that memantine might have a more significant benefit on cognition than other five drugs available.

Apathy in Alzheimer's disease

Apathy is the most common neuropsychiatric symptom in patients with Alzheimer's disease (AD). The presence of apathy has been related to greater caregiver distress, decreased quality of life, and increased morbidity. Here we review the most recent studies on this neuropsychiatric syndrome, focusing on prevalence, impact on quality of life, behavioural and neuroimaging studies, and treatment options. The results of some investigations on the behavioural and neuroanatomical profile of apathy in AD point to a role of frontostriatal circuits, specifically involving the anterior cingulate cortex. However, small and heterogeneous samples, lack of control for disease severity, and non-specific apathy scales complicate interpretation of results. Future studies might benefit from studying multiple dimensions of apathy within conceptual frameworks which allow for a deconstruction of underlying mechanisms.

The cost-effectiveness implications of suboptimal treatment for different severities of Alzheimer's disease in the UK

OBJECTIVE

This study aims to evaluate the impact of suboptimal treatment, defined in terms of lower population coverage (percentage of total patient population receiving optimal treatment) and delay to treatment on the cost-effectiveness of pharmacological therapies approved for the treatment of different severities of Alzheimer's disease (AD) in the UK.

METHODS

A 5-year Markov model was used to simulate transition to full-time care, as delay and coverage were varied for AD patients with mild-to-moderate and moderate-to-severe dementia. The time-varying predictive equations, resource use, utilities, treatment effects and mortality were derived using published sources.

RESULTS

For the cohort with moderate-to-severe dementia, cost-effectiveness was optimised when delay was minimised and coverage maximised. For mild-to-moderate dementia, results were similar but varied widely depending on the inputted cost of acetylcholinesterase inhibitors.

CONCLUSIONS

The average cost-effectiveness of pharmacological treatments for AD is sensitive to delays to treatment and population coverage. The results of this study can inform future healthcare policy in order to maximise cost-effectiveness of pharmacological therapies for AD. Copyright © 2017 John Wiley & Sons, Ltd.

An update on the safety of current therapies for Alzheimer's disease: focus on rivastigmine

Alzheimer's disease (AD) is the most common cause of major neurocognitive disorders worldwide. Despite all research efforts, therapeutic options for AD are still limited to two drug classes: cholinesterase inhibitors (ChEIs) and the NMDA-receptor antagonist memantine. Donepezil, rivastigmine and galantamine are the three ChEIs FDA-approved as first-line treatment for AD. Although they share the same mode of action, they differ in terms of their pharmacologic characteristics and route of administration, which can impact their safety and tolerability profile. Rivastigmine, available in both oral and transdermal patch formulations, is a slowly reversible dual inhibitor of acetyl and butyryl cholinesterase, selective for the G1 isoform of acetylcholinesterase, without hepatic metabolism by the CYP-450 system. Despite its unique features, it has been associated with a higher incidence of adverse events in comparison to other ChEIs. The oral form, approved for the treatment of mild to moderate AD, is associated with a higher incidence of gastrointestinal side effects. The transdermal patch formulation approved for use across all stages of AD has been shown to have a better tolerability profile in comparison to both the oral form and even other ChEIs. One important tolerability concern is adverse dermatologic reactions, which are mostly benign, and can be either preventable or manageable. One important safety concern is the risk of treatment overdose by administering multiple patches at the same time, potentially leading to fatal outcomes. This can be prevented by educating patients and caregivers about the proper use of the patch. The goal for the future would be to optimize the patch formulation to increase both efficacy and safety.

Composition and Antioxidant, Antienzymatic and Antimicrobial Activities of Volatile Molecules from Spanish Salvia lavandulifolia (Vahl) Essential Oils

The current study describes the composition of Salvia lavandulifolia (Vahl) essential oils (SlEOs) obtained from plants cultivated in Murcia (Spain), as determined by gas chromatography. Relative and absolute concentrations, the enantiomeric ratios of chiral compounds and the in vitro antioxidant, antienzymatic and antimicrobial activities are described. The main components of the SlEOs were camphor, 1,8-cineole, camphene and α-pinene, and the main enantiomers were (+)-camphor and (-)-camphene. The activities against free radicals and the capacity to reduce and chelate metallic ions were measured. SlEO-3 showed the highest activity in ORAC, DPPH, ABTS and reducing power methods, while SlEO-1 exhibited the highest chelating power. The activity of lipoxygenase and acetylcholinesterase could be inhibited by all the SlEOs, being bornyl acetate and limonene the most active individual compounds against lipoxygenase and 1,8-cineole against acetylcholinesterase. SlEOs and some individual compounds inhibited Escherichia coli, Staphylococcus aureus and Candida albicans. These results increase our knowledge of SlEOs and, particularly, provide for the first time a complete characterization of SlEOs from Murcia, Spain, while proposing possible biotechnological uses for them.

Long-term effect of galantamine on cognitive function in patients with Alzheimer's disease versus a simulated disease trajectory: an observational study in the clinical setting

BACKGROUND

Long-term maintenance of cognitive function is an important goal of treatment for Alzheimer's disease (AD), but evidence about the long-term efficacy of cholinesterase inhibitors is sparse. To evaluate the long-term efficacy and safety of galantamine for AD in routine clinical practice, we conducted a 72-week post-marketing surveillance study. The effect of galantamine on cognitive function was estimated in comparison with a simulated disease trajectory.

PATIENTS AND METHODS

Patients with mild-to-moderate AD received flexible dosing of galantamine (16-24 mg/day) during this study. Cognitive function was assessed by the mini mental state examination (MMSE) and the clinical status was determined by the Clinical Global Impression-Improvement (CGI-I). Changes of the MMSE score without treatment were estimated in each patient using Mendiondo's model. Generalized linear mixed model analysis was performed to compare the simulated MMSE scores with the actual scores.

RESULTS

Of the 661 patients who were enrolled, 642 were evaluable for safety and 554 were assessed for efficacy. The discontinuation rate was 46.73%. Cognitive decline indicated by the mean change of actual MMSE scores was significantly smaller than the simulated decline. Individual analysis demonstrated that >70% of patients had better actual MMSE scores than their simulated scores. Significant improvement of CGI-I was also observed during the observation period. Adverse events occurred in 28.5% of patients and were serious in 8.41%. The reported events generally corresponded with the safety profile of galantamine in previous studies.

CONCLUSION

These findings support the long-term efficacy of galantamine for maintaining cognitive function and the clinical state in AD patients. Treatment with galantamine was generally safe. Importantly, this study revealed that galantamine improved cognitive function above the predicted level in >70% of the patients.

The comparative efficacy and safety of cholinesterase inhibitors in patients with mild-to-moderate Alzheimer's disease: a Bayesian network meta-analysis

BACKGROUND

Comparative evidence for efficacy and safety of second-generation cholinesterase inhibitors (ChEIs) is still sparse.

OBJECTIVES

The purpose of this research is to compare three ChEIs, donepezil, galantamine and rivastigmine, in patients with mild-to-moderate Alzheimer's disease (AD).

METHODS

We conducted a systematic review for published articles and included randomised, double-blind, placebo-controlled trials and head-to-head randomised trials evaluating the efficacy and safety of ChEIs in patients with AD. We examined Alzheimer's Disease Assessment Scale, cognitive subscale (ADAS-Cog), Neuropsychiatric Inventory (NPI), Clinician's Interview-Based Impression of Change plus caregiver's input (CIBIC+) and Clinical Global Impression of Change (CGIC) as efficacy endpoints. Withdrawals due to adverse events and number of patients experiencing nausea, vomiting, diarrhoea and dizziness were examined as safety profiles. Network meta-analyses were sequentially performed for efficacy and safety outcomes based on drug/dose treatment conditions.

RESULTS

Among the 21 trials included, network meta-analysis showed that all treatments were significantly more efficacious than placebo in cognition measured by ADAS-Cog. All treatments except galantamine were significantly more efficacious than placebo in global change in CIBIC+ or CGIC. Across all conditions, no significant efficacy was observed in neuropsychiatric symptoms measured by NPI. Derived hierarchies in the efficacy of treatment conditions were variables across efficacy and safety.

CONCLUSIONS

Our analysis is the first attempt to incorporate available direct and indirect evidence. The results suggest that ChEIs should have significant efficacy for cognition and global change assessment, but the efficacy on neuropsychiatric symptoms is questionable in patients with mild-to-moderate AD.