Escitalopram for agitation in Alzheimer's disease (S-CitAD): Methods and design of an investigator-initiated, randomized, controlled, multicenter clinical trial

iPSC-derived hindbrain organoids to evaluate escitalopram oxalate treatment responses targeting neuropsychiatric symptoms in Alzheimer's disease

Alzheimer's disease (AD) is the most common cause of dementia, and the gradual deterioration of brain function eventually leads to death. Almost all AD patients suffer from neuropsychiatric symptoms (NPS), the emergence of which correlates with dysfunctional serotonergic systems. Our aim is to generate hindbrain organoids containing serotonergic neurons using human induced Pluripotent Stem Cells (iPSCs). Work presented here is laying the groundwork for the application of hindbrain organoids to evaluate individual differences in disease progression, NPS development, and pharmacological treatment response. Human peripheral blood mononuclear cells (PBMCs) from healthy volunteers (n = 3), an AD patient without NPS (n = 1), and AD patients with NPS (n = 2) were reprogrammed into iPSCs and subsequently differentiated into hindbrain organoids. The presence of serotonergic neurons was confirmed by quantitative reverse transcription PCR, flow cytometry, immunocytochemistry, and detection of released serotonin (5-HT). We successfully reprogrammed PBMCs into 6 iPSC lines, and subsequently generated hindbrain organoids from 6 individuals to study inter-patient variability using a precision medicine approach. To assess patient-specific treatment effects, organoids were treated with different concentrations of escitalopram oxalate, commonly prescribed for NPS. Changes in 5-HT levels before and after treatment with escitalopram were dose-dependent and variable across patients. Organoids from different people responded differently to the application of escitalopram in vitro. We propose that this 3D platform might be effectively used for drug screening purposes to predict patients with NPS most likely to respond to treatment in vivo and to understand the heterogeneity of treatment responses.

Progress in Pharmacologic Management of Neuropsychiatric Syndromes in Neurodegenerative Disorders: A Review

Importance

Neuropsychiatric syndromes (NPSs) are common in neurodegenerative disorders (NDDs); compromise the quality of life of patients and their care partners; and are associated with faster disease progression, earlier need for nursing home care, and poorer quality of life. Advances in translational pharmacology, clinical trial design and conduct, and understanding of the pathobiology of NDDs are bringing new therapies to clinical care.

Observations

Consensus definitions have evolved for psychosis, agitation, apathy, depression, and disinhibition in NDDs. Psychosocial interventions may reduce mild behavioral symptoms in patients with NDD, and pharmacotherapy is available for NPSs in NDDs. Brexpiprazole is approved for treatment of agitation associated with Alzheimer disease dementia, and pimavanserin is approved for treatment of delusions and hallucinations associated with psychosis of Parkinson disease. Trials are being conducted across several of the NDDs, and a variety of mechanisms of action are being assessed for their effect on NPSs.

Conclusions and Relevance

Detection and characterization of NPSs in patients with NDDs is the foundation for excellent care. New definitions for NPSs in NDDs may inform choices regarding clinical trial populations and translate into clinical practice. Psychosocial and pharmacologic therapies may reduce behavioral symptoms and improve quality of life for patients and caregivers. Approved agents may establish regulatory precedents, demonstrate successful trial strategies, and provide the foundation for further advances in treatment development.

Dementia Prevention and Treatment: A Narrative Review

Importance

Dementia affects 10% of those 65 years or older and 35% of those 90 years or older, often with profound cognitive, behavioral, and functional consequences. As the baby boomers and subsequent generations age, effective preventive and treatment strategies will assume increasing importance.

Observations

Preventive measures are aimed at modifiable risk factors, many of which have been identified. To date, no randomized clinical trial data conclusively confirm that interventions of any kind can prevent dementia. Nevertheless, addressing risk factors may have other health benefits and should be considered. Alzheimer disease can be treated with cholinesterase inhibitors, memantine, and antiamyloid immunomodulators, with the last modestly slowing cognitive and functional decline in people with mild cognitive impairment or mild dementia due to Alzheimer disease. Cholinesterase inhibitors and memantine may benefit persons with other types of dementia, including dementia with Lewy bodies, Parkinson disease dementia, vascular dementia, and dementia due to traumatic brain injury. Behavioral and psychological symptoms of dementia are best treated with nonpharmacologic management, including identifying and mitigating the underlying causes and individually tailored behavioral approaches. Psychotropic medications have minimal evidence of efficacy for treating these symptoms and are associated with increased mortality and clinically meaningful risks of falls and cognitive decline. Several emerging prevention and treatment strategies hold promise to improve dementia care in the future.

Conclusions and Relevance

Although current prevention and treatment approaches to dementia have been less than optimally successful, substantial investments in dementia research will undoubtedly provide new answers to reducing the burden of dementia worldwide.

Reimagining old drugs with new tricks: Mechanisms, strategies and notable success stories in drug repurposing for neurological diseases

Recent evolution in drug repurposing has brought new anticipation, especially in the conflict against neurodegenerative diseases (NDDs). The traditional approach to developing novel drugs for these complex disorders is laborious, time-consuming, and often abortive. However, drug reprofiling which is the implementation of illuminating novel therapeutic applications of existing approved drugs, has shown potential as a promising strategy to accelerate the hunt for therapeutics. The advancement of computational approaches and artificial intelligence has expedited drug repurposing. These progressive technologies have enabled scientists to analyse extensive datasets and predict potential drug-disease interactions. By prospecting into the existing pharmacological knowledge, scientists can recognise potential therapeutic candidates for reprofiling, saving precious time and resources. Preclinical models have also played a pivotal role in this field, confirming the effectiveness and mechanisms of action of repurposed drugs. Several studies have occurred in recent years, including the discovery of available drugs that demonstrate significant protective effects in NDDs, relieve debilitating symptoms, or slow down the progression of the disease. These findings highlight the potential of repurposed drugs to change the landscape of NDD treatment. Here, we present an overview of recent developments and major advances in drug repurposing intending to provide an in-depth analysis of traditional drug discovery and the strategies, approaches and technologies that have contributed to drug repositioning. In addition, this chapter attempts to highlight successful case studies of drug repositioning in various therapeutic areas related to NDDs and explore the clinical trials, challenges and limitations faced by researchers in the field. Finally, the importance of drug repositioning in drug discovery and development and its potential to address discontented medical needs is also highlighted.

Neuropsychiatric Manifestations in Alzheimer's Disease Patients: Genetics and Treatment Options

BACKGROUND

Alzheimer's disease (AD) is characterized by neuropsychiatric symptoms (NPS), which cause great misery to those with dementia and those who care for them and may lead to early institutionalization.

OBJECTIVE

The present systematic review aims to discuss the various aspects of Alzheimer's, including treatment options.

METHODS

The databases Embase, PubMed, and Web of Science were searched to collect data.

RESULTS

Incipient cognitive deterioration is commonly accompanied by these early warning signals of neurocognitive diseases. The neurobiology of NPSs in Alzheimer's disease, as well as particular symptoms, including psychosis, agitation, apathy, sadness, and sleep disorders, will be examined in this review. For NPSs in Alzheimer's disease, clinical trial designs, as well as regulatory issues, were also addressed. A fresh wave of research, however, is helping to push the discipline ahead. For medication development and repurposing, we highlight the most recent results in genetics, neuroimaging, and neurobiology. Even though identifying and treating psychosis in adults with dementia is still a challenging endeavor, new options are coming up that give the field fresh focus and hope. Conclsuion: It can be concluded from the complete literature survey that Alzheimer's-related psychosis as well as other symptoms that are not psychotic, have made significant progress in the last decade. These milestones in the development of safer, more effective treatments have been achieved as a consequence of great focus on non-pharmacological interventions like DICE or WHELD; the investigation into ways to improve existing drugs like aripiprazole, risperidone, amisulpride, and Escitalopram for safer precision-based treatment; and the development of a clinical trial program for pimavanserin.

Serotonin Receptors as a Potential Target in the Treatment of Alzheimer's Disease

Alzheimer's disease (AD) is the most common cause of dementia worldwide that has an increasing impact on aging societies. Besides its critical role in the control of various physiological functions and behavior, brain serotonin (5-HT) system is involved in the regulation of migration, proliferation, differentiation, maturation, and programmed death of neurons. At the same time, a growing body of evidence indicates the involvement of 5-HT neurotransmission in the formation of insoluble aggregates of β-amyloid and tau protein, the main histopathological signs of AD. The review describes the role of various 5-HT receptors and intracellular signaling cascades induced by them in the pathological processes leading to the development of AD, first of all, in protein aggregation. Changes in the functioning of certain types of 5-HT receptors or associated intracellular signaling mediators prevent accumulation of β-amyloid plaques and tau protein neurofibrillary tangles. Based on the experimental data, it can be suggested that the use of 5-HT receptors as new drug targets will not only improve cognitive performance in AD, but will be also important in treating the causes of AD-related dementia.

Excitatory Neurons Derived from Human-Induced Pluripotent Stem Cells Show Transcriptomic Differences in Alzheimer's Patients from Controls

The recent advances in creating pluripotent stem cells from somatic cells and differentiating them into a variety of cell types is allowing us to study them without the caveats associated with disease-related changes. We generated induced Pluripotent Stem Cells (iPSCs) from eight Alzheimer's disease (AD) patients and six controls and used lentiviral delivery to differentiate them into excitatory glutamatergic neurons. We then performed RNA sequencing on these neurons and compared the Alzheimer's and control transcriptomes. We found that 621 genes show differences in expression levels at adjusted p < 0.05 between the case and control derived neurons. These genes show significant overlap and directional concordance with genes reported from a single-cell transcriptome study of AD patients; they include five genes implicated in AD from genome-wide association studies and they appear to be part of a larger functional network as indicated by an excess of interactions between them observed in the protein-protein interaction database STRING. Exploratory analysis with Uniform Manifold Approximation and Projection (UMAP) suggests distinct clusters of patients, based on gene expression, who may be clinically different. Our research outcomes will enable the precise identification of distinct biological subtypes among individuals with Alzheimer's disease, facilitating the implementation of tailored precision medicine strategies.

A 2023 update on the advancements in the treatment of agitation in Alzheimer's disease

INTRODUCTION

Neuropsychiatric symptoms (NPS) in Alzheimer's Disease (AD) are associated with negative outcomes for patients and their care partners. Agitation is one of the most common and distressing NPS, yet we lack safe and effective treatment options. While nonpharmacologic interventions are considered first line treatment, these may not be effective or appropriate for every patient. Our current approaches to the pharmacologic treatment of agitation in AD consist of the off-label use of antipsychotics, sedative/hypnotics, anxiolytics, mood-stabilizing anticonvulsants, acetylcholinesterase inhibitors, NMDA receptor antagonists, and antidepressants. Despite their prevalent use, they have questionable efficacy and significant safety concerns.

AREAS COVERED

Advances in the understanding of neurobiological mechanisms of agitation have fueled recent clinical trials. This article is an update to our 2017 review. A comprehensive search of ClinicalTrials.gov was completed from January 2017 to June 2022 using the search terms "Alzheimer's Disease" and "Agitation". A subsequent scoping review was completed in PubMed and Google Scholar. Several agents were identified for promise in treating agitation, including: brexpiprazole, cannabinoids, dexmedetomidine, dextromethorphan, escitalopram, masupirdine, and prazosin.

EXPERT OPINION

Clinical trials remain underway utilizing both novel and repurposed agents to address symptoms of agitation in AD. With increasing understanding of the neurobiological mechanisms that fuel the development of agitation in AD, the use of enhanced trial design and conduct, advanced statistical approaches, and accelerated pathways for regulatory approval, we are advancing closer to having safe and efficacious treatment options for agitation in AD.

Comparative efficacy and safety of antidepressant therapy for the agitation of dementia: A systematic review and network meta-analysis

Background

Dementia is a clinical syndrome commonly seen in the elderly individuals. With the prevalence of dementia, the incidence of neuropsychiatric symptoms in dementia patients is increasing annually. Agitation, as one of the neuropsychiatric symptoms, has a serious impact on the quality of life of patients with dementia. Several antidepressant drugs have been shown to be effective for treating agitated behavior symptoms in patients with dementia, but there are no direct comparisons among those drugs. Therefore, we carried out a network meta-analysis (NMA) to examine the efficacy and safety of those antidepressant drugs.

Methods

We searched eight databases (PubMed, Cochrane Library, Web of Science, Embase, Wanfang Database, China National Knowledge Infrastructure, VIP Database and China biomedical literature service) from their inception to 6 November 2022. Randomized controlled trials (RCTs) reporting the efficacy and safety of antidepressant drugs in treating agitated behavior symptoms in patients with dementia were included in our analysis. The quality assessment was carried out by two researchers individually and the analysis was based on the frequency method.

Results

Twelve articles with 1,146 participants were included in our analysis. Based on the outcome of the agitation score, treatment with citalopram (standardized mean difference, SMD = -0.44, 95% confidence interval, 95% CI = -0.72 to -0.16) showed significant benefits over the placebo group. Treatment with trazodone (odds ratio, OR = 4.58, 95% CI = 1.12-18.69) was associated with a higher risk of total adverse events compared with a placebo treatment.

Conclusion

Among the antidepressant drugs included in this study, treatment with citalopram was probably the only optimal intervention, when considering the improvement from baseline to the end of the intervention, and there was not a statistically significant difference in safety when compared with a placebo treatment.

Systematic review registration

https://www.crd.york.ac.uk/prospero/#recordDetails, identifier: PROSPERO, CRD42022320932.

Psychotic Disorders in the Elderly: Diagnosis, Epidemiology, and Treatment

This review covers the latest advances in our understanding of psychosis in the elderly population with respect to diagnosis, epidemiology, and treatment. Major topics of discussion include late life psychiatric disorders such as schizophrenia, schizoaffective disorder, and delusional disorder as well as dementia-related psychosis. Clinical differences between early-onset and late-onset disorders are reviewed in terms of prevalence, symptomatology, and approach to treatment. Newly revised research and clinical criteria for dementia-related psychosis are referenced. The evidence base for emerging therapies including citalopram and pimavanserin in relation to conventional therapies such as atypical antipsychotics are discussed..

Risks and benefits of current and novel drugs to treat agitation in Alzheimer's disease

INTRODUCTION

At present, no pharmacological interventions have been approved for the treatment of agitation in Alzheimer's disease (AD), an important neuropsychiatric symptom that has been linked to increased mortality and greater caregiver burden. Antipsychotics offer some benefit, but increase the risk of adverse events such as falls, extrapyramidal symptoms, stroke, and mortality. Over the past 10 years, several new and repurposed medications have shown promise for treating AD-associated agitation.

AREAS COVERED

We review the risks and benefits of emerging therapies for agitation in AD, which include newer atypical antipsychotics, selective serotonin reuptake inhibitors, cannabinoids, and dextromethorphan combination products. Other drugs such as mirtazapine, prazosin, and lithium are also discussed. Clinicaltrials.gov, PubMed/MEDLINE, EMBASE and Cochrane Central databases were searched for relevant studies from 1 January 2012 to 1 May 2022.

EXPERT OPINION

At the present time, there are no pharmacological interventions for the treatment of agitation in AD whose benefits clearly outweigh their potential safety concerns. Therefore, management of agitation in AD should primarily be based on non-pharmacological approaches. When medications are considered necessary, they should only be initiated with the caregiver's appreciation of their risks and benefits and with careful and ongoing assessment of their safety.

Management in severe dementia: recommendations of the Scientific Department of Cognitive Neurology and Aging of the Brazilian Academy of Neurology

ABSTRACT Alzheimer’s disease (AD) and other neurodegenerative dementias have a progressive course, impairing cognition, functional capacity, and behavior. Most studies have focused on AD. Severe dementia is associated with increased age, higher morbidity-mortality, and rising costs of care. It is fundamental to recognize that severe dementia is the longest period of progression, with patients living for many years in this stage. It is the most heterogeneous phase in the process, with different abilities and life expectancies. This practice guideline focuses on severe dementia to improve management and care in this stage of dementia. As it is a long period in the continuum of dementia, clinical practice should consider non-pharmacological and pharmacological approaches. Multidisciplinary interventions (physical therapy, speech therapy, nutrition, nursing, and others) are essential, besides educational and support to caregivers.

Manejo das demências em fase avançada: recomendações do Departamento Científico de Neurologia Cognitiva e do Envelhecimento da Academia Brasileira de Neurologia

RESUMO A doença de Alzheimer (DA) e outras demências neurodegenerativas têm um curso progressivo com comprometimento da cognição, capacidade funcional e comportamento. A maioria dos estudos enfocou a DA. A demência grave está associada ao aumento da idade, maior morbimortalidade e aumento dos custos de cuidados. É fundamental reconhecer que a demência grave é o período mais longo de progressão, com o paciente vivendo muitos anos nesta fase. É a fase mais heterogênea do processo, com diferentes habilidades e expectativa de vida. Esta diretriz de prática concentra-se na demência grave para melhorar o manejo e o cuidado nessa fase da demência. Como um longo período no continuum da demência, as abordagens não farmacológicas e farmacológicas devem ser consideradas. Intervenções multidisciplinares (fisioterapia, fonoaudiologia, nutrição, enfermagem, entre outras) são essenciais, além de educacionais e de apoio aos cuidadores.

Understanding How Physical Exercise Improves Alzheimer’s Disease: Cholinergic and Monoaminergic Systems

Alzheimer’s disease (AD) is an age-related neurodegenerative disorder, characterized by the accumulation of proteinaceous aggregates and neurofibrillary lesions composed of β-amyloid (Aβ) peptide and hyperphosphorylated microtubule-associated protein tau, respectively. It has long been known that dysregulation of cholinergic and monoaminergic (i.e., dopaminergic, serotoninergic, and noradrenergic) systems is involved in the pathogenesis of AD. Abnormalities in neuronal activity, neurotransmitter signaling input, and receptor function exaggerate Aβ deposition and tau hyperphosphorylation. Maintenance of normal neurotransmission is essential to halt AD progression. Most neurotransmitters and neurotransmitter-related drugs modulate the pathology of AD and improve cognitive function through G protein-coupled receptors (GPCRs). Exercise therapies provide an important alternative or adjunctive intervention for AD. Cumulative evidence indicates that exercise can prevent multiple pathological features found in AD and improve cognitive function through delaying the degeneration of cholinergic and monoaminergic neurons; increasing levels of acetylcholine, norepinephrine, serotonin, and dopamine; and modulating the activity of certain neurotransmitter-related GPCRs. Emerging insights into the mechanistic links among exercise, the neurotransmitter system, and AD highlight the potential of this intervention as a therapeutic approach for AD.

Psychosis in Alzheimer disease - mechanisms, genetics and therapeutic opportunities

Psychosis is a common and distressing symptom in people with Alzheimer disease, and few safe and effective treatments are available. However, new approaches to symptom assessment and treatment are beginning to drive the field forward. New nosological perspectives have been provided by incorporating the emergence of psychotic symptoms in older adults - even in advance of dementia - into epidemiological and neurobiological frameworks as well as into diagnostic and research criteria such as the International Psychogeriatric Association criteria for psychosis in neurocognitive disorders, the Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment (ISTAART) research criteria for psychosis in neurodegenerative disease, and the ISTAART criteria for mild behavioural impairment. Here, we highlight the latest findings in genomics, neuroimaging and neurobiology that are informing approaches to drug discovery and repurposing. Current pharmacological and non-pharmacological treatment options are discussed, with a focus on safety and precision medicine. We also explore trial data for pimavanserin, a novel agent that shows promise for the treatment of psychosis in people with dementia, and discuss existing agents that might be useful but need further exploration such as escitalopram, lithium, cholinesterase inhibitors and vitamin D. Although the assessment and management of psychosis in people with dementia remain challenging, new opportunities are providing direction and hope to the field.

The Rationale and Design of Behavioral Interventions for Management of Agitation in Dementia in a Multi-Site Clinical Trial

BACKGROUND

Agitation and aggression are common in patients with Alzheimer's disease and related dementias and pose a significant burden on patients, caregivers, and the healthcare systems. Guidelines recommend personalized behavioral interventions as the first-line treatment; however, these interventions are often underutilized. The Standardizing Care for Neuropsychiatric Symptoms and Quality of Life in Dementia (StaN) study (ClinicalTrials.gov Identifier # NCT0367220) is a multisite randomized controlled trial comparing an Integrated Care Pathway, that includes a sequential pharmacological algorithm and structured behavioral interventions, with treatment-as-usual to treat agitation in dementia in long-term care and inpatient settings.

OBJECTIVE

To describe the rationale and design of structured behavioral interventions in the StaN study.

METHODS

Structured behavioral interventions are designed and implemented based on the following considerations: 1) personalization, 2) evidence base, 3) dose and duration, 4) measurement-based care, and 5) environmental factors and feasibility.

RESULTS

The process to design behavioral interventions for each individual starts with a comprehensive assessment, followed by personalized, evidence-based interventions delivered in a standardized manner with ongoing monitoring of global clinical status. Measurement-based care is used to tailor the interventions and to integrate them with pharmacotherapy.

CONCLUSION

Individualized behavioral interventions in patients with dementia may be challenging to design and implement. Here we describe a process to design and implement individualized and structured behavioral interventions in the context of a multisite trial in long-term care and inpatient settings. This process can inform the design of behavioral interventions in future trials and in clinical settings for the treatment of agitation in dementia.

Apathy as a Treatment Target in Alzheimer's Disease: Implications for Clinical Trials

Apathy is one of the most prevalent, stable and persistent neuropsychiatric symptom across the neurocognitive disorders spectrum. Recent advances in understanding of phenomenology, neurobiology and intervention trials highlight apathy as an important target for clinical intervention. We conducted a comprehensive review and critical evaluation of recent advances to determine the evidence-based suggestions for future trial designs. This review focused on 4 key areas: 1) pre-dementia states; 2) assessment; 3) mechanisms/biomarkers and 4) treatment/intervention efficacy. Considerable progress has been made in understanding apathy as a treatment target and appreciating pharmacological and non-pharmacological apathy treatment interventions. Areas requiring greater investigation include: diagnostic procedures, symptom measurement, understanding the biological mechanisms/biomarkers of apathy, and a well-formed approach to the development of treatment strategies. A better understanding of the subdomains and biological mechanisms of apathy will advance apathy as a treatment target for clinical trials.

The Clinician's Interview-Based Impression of Change (Plus caregiver input) and goal attainment in two dementia drug trials: Clinical meaningfulness and the initial treatment response

INTRODUCTION

The Clinician's Interview-Based Impression of Change Plus caregiver input (CIBIC-Plus) has been widely used in dementia drug trials to evaluate cognition, behavior, and function. New trials of symptomatic drugs forecast renewed interest in this measure.

METHODS

To test its clinical meaningfulness, we examined how CIBIC-Plus performed in two cholinesterase inhibitor trials compared to goal attainment scaling Scale (GAS) scores, a patient-reported outcome measure.

RESULTS

Net goal attainment was seen for all but one GAS domains in subjects who improved on the CIBIC-Plus. Subjects who improved initially on CIBIC-Plus scores were likely to remain improved across all other outcomes for each trial's duration, except for Disability Assessment for Dementia scores.

DISCUSSION

The initial response to treatment, as assessed by CIBIC-Plus, remained stable for most outcome measures. Even small CIBIC-Plus improvement changes are associated with clinically meaningful change as assessed by GAS. Other tests detect decline better than improvement.

Psychotropic Medication and Cognitive, Functional, and Neuropsychiatric Outcomes in Alzheimer's Disease (AD)

BACKGROUND/OBJECTIVES

There are growing concerns about the safety and efficacy of psychotropic medications in Alzheimer's disease (AD). We sought to examine associations between psychotropic medication exposure and longitudinal change in cognitive, functional, and neuropsychiatric outcomes in a large clinical AD cohort.

DESIGN

Longitudinal observational study.

SETTING

National Alzheimer's Disease Coordinating Center combining data from 39 Alzheimer's disease centers.

PARTICIPANTS

8,034 participants with AD dementia.

MEASUREMENTS

Mini-Mental State Exam (MMSE), Clinical Dementia Rating Scale-Sum of Boxes (CDR-SB), and Neuropsychiatric Inventory Questionnaire (NPI-Q) Total. Probability of exposure to medication (the propensity score, PS) calculated via logistic regression. Medication classes included all antipsychotics (atypical vs conventional), antidepressants (Selective Serotonin Reuptake Inhibitor [SSRI] vs non-SSRI), and benzodiazepines. Participants treated with a medication class were matched with participants not treated with that class with the closest-matched PS. The effect of medication treatment was assessed using linear mixed-effects models.

RESULTS

Participants had a mean (SD) age of 75.5 (9.8) years, and mean (SD) scores of MMSE 21.3 (5.7), CDR-SB 5.5 (3.4), and NPI-Q Total 4.5 (4.4). Mean duration of follow-up was 2.9-3.3 years depending on medication class. Non-SSRI antidepressant use was associated with better CDR-SB (2-year difference in change-DIC: -0.38 [-0.61, -0.15], P = .001). Atypical antipsychotic use was associated with greater decline on MMSE (DIC: -0.91 [-1.54, -0.28] P = .005) and CDR-SB scores (DIC: 0.50 [0.14, 0.86], P = .006). Notably, no drug class was associated with better NPI-Q scores.

CONCLUSIONS

Use of atypical antipsychotics was associated with poorer cognition and function, and no drug class was associated with improvement in neuropsychiatric symptoms.

Drug Development for Psychotropic, Cognitive-Enhancing, and Disease-Modifying Treatments for Alzheimer's Disease

Alzheimer's disease (AD) is a progressive neurodegenerative disorder with limited available therapies. There is progress in developing treatments for neuropsychiatric indications in AD, including agitation, psychosis, apathy, and sleep disorders. Candidate therapies progress from nonclinical and animal assessment to trials in normal volunteers (phase 1), small phase-2 trials, and larger confirmatory phase-3 trials. Biomarkers play an increasingly important role in selecting participants, stratifying populations, demonstrating target engagement, supporting disease modification, and monitoring safety. There are currently 121 agents in clinical trials, including treatments for neuropsychiatric symptoms, cognition enhancement, and disease progression. There are 27 agents in phase-1 trials, 65 in phase-2 trials, and 29 in phase-3 trials. Most of the agents in trials (80%) target disease modification. Treatments are being assessed in secondary prevention trials with cognitively normal individuals at high risk for the development of AD. There is progress in target diversification, trial designs, outcome measures, biomarkers, and trial population definitions that promise to accelerate developing new therapies for those with or at risk for AD.

Status and future directions of clinical trials in Alzheimer's disease

Amyloid-β (Aβ) senile plaques and neurofibrillary tangles of tau are generally recognized as the culprits of Alzheimer's disease (AD) and related dementia. About 25 years ago, the amyloid cascade hypotheses postulated a direct correlation of plaques with the development of AD, and it has been the dominant theory since then. In this period, more than 200 clinical trials focused mainly on targeting components of the Aβ cascade have dramatically failed, some of them in Phase III. With a greater than 99.6% failure rate at a cost of several billion from governments, industry, and private funders, therapeutic strategies targeting amyloid and tau are now under scrutiny. Therefore, it is time to reevaluate alternatives to targeting Aβ and tau as effective therapeutic strategies for AD. The diagnosis of AD is currently based on medical examination of symptoms including tests to assess memory impairment, attention, language, and other thinking skills. This is complemented with brain scans, such as computed tomography, magnetic resonance imaging, or positron emission tomography with the help of imaging probes targeting Aβ or tau deposits. This approach has contributed to the tunnel vision focus on Aβ and tau as the main culprits of AD. However, events upstream of these proteopathies (age-related impaired neuronal bioenergetics, lysosome function, neurotrophic signaling, and neuroinflammation, among others) are almost surely where the development of alternative therapeutic interventions should be targeted. Here, we present the current status of therapeutic candidates targeting diverse mechanisms and strategies including Aβ and tau, proteins involved in Aβ production and trafficking (ApoE, α/β/γ-secretases), neuroinflammation, neurotransmitters, neuroprotective agents antimicrobials, and gene and stem cell therapy. There are currently around 33 compounds in Phase III, 78 in Phase II, and 32 more in Phase I trials. With the current world health crisis of increased dementia in a rapidly aging population, effective AD therapies are desperately needed.

Alzheimer's disease drug development pipeline: 2020

INTRODUCTION

Alzheimer's disease (AD) is a growing public health concern affecting millions of patients worldwide and costing billions of dollars annually. We review the pipeline of drugs and biologics in clinical trials for the treatment of AD. We use the Common Alzheimer's and Related Dementias Research Ontology (CADRO) to classify treatment targets and mechanisms of action. We review our annual pipeline reports for the past 5 years to provide longitudinal insight into clinical trials and drug development for AD.

METHODS

We reviewed ClinicalTrials.gov as of February 27, 2020, and identified all trials of pharmacologic agents currently being developed for treatment of AD as represented on this widely used U.S. Food and Drug Administration registry.

RESULTS

There are 121 agents in clinical trials for the treatment of AD. Twenty-nine agents are in 36 Phase 3 trials, 65 agents are in 73 Phase 2 trials, and 27 agents are in 27 Phase 1 trials. Twelve agents in trials target cognitive enhancement and 12 are intended to treat neuropsychiatric and behavioral symptoms. There are 97 agents in disease modification trials. Compared to the 2019 pipeline, there is an increase in the number of disease-modifying agents targeting pathways other than amyloid or tau.

DISCUSSION

The 2020 pipeline has innovations in clinical trials and treatment targets that provide hope for greater success in AD drug development programs. Review of clinical trials over the past 5 years show that there is progressive emphasis on non-amyloid targets, including candidate treatments for inflammation, synapse and neuronal protection, vascular factors, neurogenesis, and epigenetic interventions. There has been a marked growth in repurposed agents in the pipeline.

The Efficacy of Sertraline, Escitalopram, and Nicergoline in the Treatment of Depression and Apathy in Alzheimer's Disease: The Okayama Depression and Apathy Project (ODAP)

BACKGROUND

Neuropsychiatric symptoms of dementia such as depression and apathy in patients with Alzheimer's disease (AD) are associated with a lower quality of life.

OBJECTIVE

We aimed to determine the efficacy of two antidepressants and one antipathy drug in the treatment of depression and apathy in AD patients.

METHODS

In the present study, we evaluated the efficacy of sertraline (n = 11; average dose = 31.8 mg), escitalopram (n = 13; average dose = 7.3 mg), and nicergoline (n = 9; average dose = 14.5 mg) in treating depression and apathy over a period of 3 months (M).The 33 patients with AD demonstrated high Geriatric Depression Scale (GDS) (>5) or a high Apathy Scale (AS) (>16) scores.

RESULTS

The patients receiving escitalopram treatment showed a significant improvement in GDS score from baseline (8.2±3.5) to 3 M (5.7±2.6, p = 0.04), and the patients receiving sertraline treatment showed a significant improvement in AS score from baseline (20.8±5.2) to 3 M (16.8±6.1, p = 0.05); however, no significant changes were noted in patients receiving nicergoline.

CONCLUSION

These results provide novel information on the efficacy of sertraline and escitalopram in the treatment of apathy and depression, respectively, in patients with AD.