Pharmacokinetic evaluation of donanemab for the treatment of Alzheimer's

INTRODUCTION

Donanemab is a humanized monoclonal antibody that significantly reduces cerebral amyloid plaques in Alzheimer's Disease (AD). It can delay disease progression and cognitive decline, making it one of the most promising disease-modifying treatments in the current treatment landscape.

AREAS COVERED

This paper covers the current literature available on pharmacokinetics, pharmacodynamics, safety, and tolerability of donanemab. Publications from PubMed and Google were reviewed. A summary of regulatory approvals and current clinical data is also provided.

EXPERT OPINION/COMMENTARY

Donanemab as a therapy for AD has more effective disease-modifying effects compared to lecanemab. Donanemab appears generally well-tolerated; however, it may have higher rates of severe side effects, such as amyloid-related imaging abnormalities (ARIA), that could lead to death. Guidelines for frequency of MRI monitoring for ARIA/safety are pending but will be integral to determining its use. Despite some limitations, donanemab is expected to receive FDA approval, giving clinicians access to another disease-modifying drug. Overall, more data is needed about donanemab, especially relating to safety, efficacy, cost, and integration with other treatments, but its development signifies progress in AD treatment.

Profiling lecanemab as a treatment option for Alzheimer's disease

INTRODUCTION

In July 2023, the U.S. Food and Drug Administration (FDA) granted full approval to lecanemab for the treatment of mild cognitive impairment (MCI) due to Alzheimer's disease (AD) and mild AD dementia. Considering the limited treatment options for AD, the approval of lecanemab offers hope and opens the door for other disease-modifying therapies in the pipeline.

AREAS COVERED

In this review, the authors summarize the FDA treatment guidelines, other anti-amyloid agents, and drug information relevant to prescribers, such as pharmacology and pharmacokinetics. Relevant clinical trial outcomes are discussed along with their significance and controversies.

EXPERT OPINION

While questions remain about the magnitude of lecanemab's clinical impact, its approval signifies major progress in addressing the underlying pathology of AD. The authors have confidence in lecanemab as a promising treatment option and foresee exciting advancements on the 5-year horizon. Yet, further research is needed regarding trials beyond 18 months, post-marketing surveillance, and lecanameb in combination with existing treatments and lifestyle interventions.

Brexpiprazole for the Treatment of Agitation in Alzheimer Dementia: A Randomized Clinical Trial

Importance

Agitation is a prevalent, distressing, and burdensome manifestation of Alzheimer dementia in need of an efficacious, safe, and well-tolerated treatment.

Objective

To confirm the efficacy, safety, and tolerability of brexpiprazole in patients with agitation in Alzheimer dementia.

Design, Setting, and Participants

This randomized clinical trial was a 12-week, double-blind, placebo-controlled, fixed-dose, parallel-arm trial that ran from May 2018 to June 2022 at 123 clinical trial sites in Europe and the United States. Participants included patients with agitation in Alzheimer dementia in a care facility or community-based setting. Stable Alzheimer disease medications were permitted.

Interventions

In this 2-arm trial, patients were randomized to receive oral brexpiprazole or placebo (2:1 ratio) for 12 weeks. Within the brexpiprazole arm, patients were further randomized to receive fixed doses of 2 mg/d or 3 mg/d in a 1:2 ratio.

Main Outcomes and Measures

The primary end point was change in Cohen-Mansfield Agitation Inventory total score (which measures the frequency of 29 agitated behaviors) from baseline to week 12 for brexpiprazole, 2 or 3 mg, vs placebo. Safety was assessed by standard measures, including treatment-emergent adverse events.

Results

A total of 345 patients were randomized to receive brexpiprazole (n = 228) or placebo (n = 117); completion rates were 198 (86.8%) for brexpiprazole and 104 (88.9%) for placebo. Mean (SD) age was 74.0 (7.5) years, and 195 of 345 patients were female (56.5%). Patients receiving brexpiprazole, 2 or 3 mg (n = 225), demonstrated statistically significantly greater improvement than those taking placebo (n = 116) in Cohen-Mansfield Agitation Inventory total score from baseline to week 12 (brexpiprazole baseline, 80.6, mean change, -22.6; placebo baseline, 79.2, mean change, -17.3; least-squares mean difference, -5.32; 95% CI, -8.77 to -1.87; P = .003; Cohen d effect size, 0.35). No treatment-emergent adverse events had an incidence of 5% or more with brexpiprazole and greater incidence than placebo. The proportion of patients who discontinued because of adverse events was 12 of 226 (5.3%) for brexpiprazole and 5 of 116 (4.3%) for placebo.

Conclusions and Relevance

In this study, patients with Alzheimer dementia who took brexpiprazole, 2 or 3 mg, showed a statistically significant improvement vs placebo in agitation over 12 weeks. Brexpiprazole was generally well tolerated over 12 weeks in this vulnerable patient population.

Trial Registration

ClinicalTrials.gov Identifier: NCT03548584.

The aquaporin-4 water channel and updates on its potential as a drug target for Alzheimer's disease

INTRODUCTION

Although there are several FDA-approved treatments for Alzheimer's disease (AD), only recently have disease-modifying therapies received approval for use in patients. In this narrative review, we examine the history of aquaporin-4 (AQP4) as a therapeutic target for NMOSD (neuromyelitis optica spectrum disorder) and as a potential therapeutic target for AD.

AREAS COVERED

We review the basic science and discovery of AQP4, a transmembrane water-channel essential to regulating water balance in the central nervous system (CNS). We also review the pathogenesis of NMOSD, an autoimmune disease characterized by the destruction of cells that express AQP4. Then, we review how AQP4 is likely involved in the pathogenesis of Alzheimer's disease (AD). Finally, we discuss future challenges with drug design that would modulate AQP4 to potentially slow AD development. The literature search for this article consisted of searching Google Scholar and PubMed for permutations of the keywords 'Alzheimer's disease,' 'aquaporin-4,' 'neuromyelitis optica,' and their abbreviations.

EXPERT OPINION

We place research into AQP4 into context with other recent developments in AD research. A major difficulty with drug development for Alzheimer's is the lack of strategies to cleanly target the early pathogenesis of the disease. Targeting AQP4 may provide such a strategy.

Comparison of the Impact of the Mediterranean Diet, Anti-Inflammatory Diet, Seventh-Day Adventist Diet, and Ketogenic Diet Relative to Cognition and Cognitive Decline

PURPOSE OF REVIEW

Increasing evidence points toward the importance of diet and its impact on cognitive decline. This review seeks to clarify the impact of four diets on cognition: the Mediterranean diet, the anti-inflammatory diet, the Seventh Day Adventist diet, and the Ketogenic diet.

RECENT FINDINGS

Of the diets reviewed, the Mediterranean diet provides the strongest evidence for efficacy. Studies regarding the anti-inflammatory diet and Seventh Day Adventist diet are sparse, heterogeneous in quality and outcome measurements, providing limited reliable data. There is also minimal research confirming the cognitive benefits of the Ketogenic diet. Increasing evidence supports the use of the Mediterranean diet to reduce cognitive decline. The MIND-diet, a combination of the Mediterranean and DASH diets, seems especially promising, likely due to its anti-inflammatory properties. The Ketogenic diet may also have potential efficacy; however, adherence in older populations may be difficult given frequent adverse effects. Future research should focus on long-term, well-controlled studies confirming the impact of various diets, as well as the combination of diets and lifestyle modification.

Development and assessment of a brief screening tool for psychosis in dementia

BACKGROUND

Hallucinations and delusions associated with dementia-related psychosis (DRP) can occur in persons with dementia-however, quickly screening for these symptoms in busy clinical settings can be challenging. We developed the DRP3 Screen, a novel tool to screen for psychosis in clinical settings; performed an Alignment Exercise to determine association of the DRP3 Screen with established psychosis/DRP reference assessments; and retrospectively assessed the ability of the DRP3 Screen to detect patients with DRP enrolled in a clinical trial (HARMONY, NCT03325556).

METHODS

The DRP3 Screen comprises 3 yes/no questions and was developed by Acadia Pharmaceuticals Inc. in collaboration with an international team of six subject matter experts (SMEs). Through facilitated discussions, the panel developed questions addressing key aspects of psychosis in dementia. SMEs independently rated level of alignment (Table) of the questions with current reference assessments (SAPS-H+D, NPI-Q, IPA Criteria) to determine if the symptoms itemized in those assessments would be captured by ≥1 DRP3 Screen question. Criteria for association with a reference assessment item was mean rating ≥2.0 for at least one DRP3 Screen question (95% CI, lower limit ≥1.3). Inter-rater reliability of the Alignment Exercise for individual reference assessments was assessed using Fleiss' kappa statistic. For retrospective application of the DRP3 Screen to HARMONY, patients were considered likely to have been identified by the DRP3 Screen if they were positive (score ≥2) on ≥1 SAPS-H+D items that were positively associated with the DRP3 Screen.

RESULTS

All items across 3 reference assessments (except SAPS-H+D D6, somatic delusions) were associated with the DRP3 Screen. Mean level of alignment segregated to none/some (0.3-1.8) and most/all (2.3-3.0) with significant inter-rater agreement of the DRP3 Screen with the SAPS-H+D, NPI-Q and IPA Criteria, (kappa values: 0.37, 0.26, and 0.45, respectively; p<.0001). Retrospective application of the DRP3 Screen to HARMONY identified all trial enrollees.

CONCLUSIONS

The novel DRP3 Screen is a brief tool designed to assess the presence of hallucinations and delusions in persons with dementia. Potential for its clinical application has been established through association with current reference assessments, with significant agreement among raters; and through successful retrospective application to an existing trial population.

Telememory - A systematic, automated, digital reminiscence therapy platform for patients with dementia: A pilot project

BACKGROUND

Reminiscence Therapy (RT) is a therapeutic modality for cognitive stimulation therapy. The difficulty employing this therapy is gathering personal and family memories to engage the patient in life-review. Digital RT (DRT) bypasses these difficulties, allowing family to engage in the creation of digital content designed to highlight patient-specific memories administered via internet and communication technology. The efficacy of DRT has been demonstrated in controlled studies with positive results when compared with traditional reminiscence therapy.[1] The focus is how DRT (a non-pharmacological intervention) reduces dementia related behavior. Based on this previously published research, we share preliminary results utilizing a proprietary platform to administer DRT to dementia patients. We implemented DRT through a novel technology platform. The platform runs on Android-based devices. The solution standardizes collection of patient biographical information through care team interaction. Digital artifacts (photos, music, videos) are assembled through proprietary interfaces to produce a patient-centric DRT session. DRT sessions are shared with patient 3-5 times per week, allowing patient to experience benefits of reminiscence therapy through an automated interface. Minimal on-staff time is needed. Proprietary AI, which is currently being refined, records patient reactions to stimuli presented throughout each session, allowing future sessions to be tailored towards those stimuli producing the highest level of positive response. DRT was administered via the Telememory solution to five (5) patients at skilled nursing facilities. Empirical data concerning mood improvement was gathered remotely and onsite by Telememory and facility staff. Assistance from onsite facility staff was minimal, limited to the initiation of DRT sessions and patient observation. Results were positive. Patients demonstrated consistent mood improvement sessions. In some cases, mood improvement extended beyond treatment. Mood improvement and patient mental status was confirmed by Neuropsychiatric Index evaluations. The quality of outcomes improved with increased patient/family/caregiver memory data input. Patients experienced immediate and post-treatment benefits as observed by onsite caregiver staff. Best results were achieved with closely curated content from each patient's past. Highest cognitive stimulation and mood improvement occurred from the presentation of digital artifacts provided by family members and primary caregivers.

Using Telemedicine to Assess and Manage Psychosis Among Outpatients with Neurodegenerative Disease

The presence of hallucinations and delusions in patients with neurodegenerative disease correlates negatively with function, cognition, quality of life, and survival. When these patients still have insight, the treatment of mild hallucinations may reduce the risk of progression to more severe symptoms, specifically hallucinations without insight or delusions. On October 22, 2020, a multidisciplinary consensus panel comprising United States-based experts in geriatric psychiatry, geriatric medicine, family medicine, movement disorders, and neuropsychology was convened remotely to discuss best practices for using telemedicine to evaluate, diagnose, and treat psychosis in patients with neurodegenerative diseases. This review reflects the opinions and recommendations discussed at this meeting. Despite drawbacks, telemedicine can offer several advantages over in-person care, particularly for older adults, and may be a unique opportunity for care of patients with neuropsychiatric symptoms. While telemedicine may not be suitable for all patients, it allows the involvement of specialists from multiple geographic locations and the extension of care to homebound individuals. Patients with neurodegenerative diseases who are likely to become homebound as the disease advances may benefit greatly from telemedicine as a standard of care. Healthcare provided via telemedicine should be nothing less than what would be offered to the patient in person. Telemedicine may present some difficulties, including technological issues and inherent constraints of remote care, but with proper planning many problems could be diminished. Technical issues associated with telemedicine are inevitable but may be partially offset by providing clear directions ahead of any tele-visit to ensure connectivity and access to the videoconferencing platform. Alternative procedures to communicate should be established in the eventuality of technological issues. Using these strategies, telemedicine can serve as a valuable complement to traditional in-person practices for the diagnosis and management of hallucinations and delusions associated with Parkinson’s disease psychosis or dementia-related psychosis.

Over-The-Counter Remedies in Older Adults: Patterns of Use, Potential Pitfalls, and Proposed Solutions

Over-the-counter (OTC) products such as pharmaceuticals, dietary supplements, vitamins, and herbal remedies are widely available and copiously used by older adults for health maintenance and symptom management. Owing to physiology, multimorbidity, and polypharmacy, this population is particularly vulnerable to inappropriate use of OTC products, adverse effects, and drug interactions. While OTC pharmaceuticals are bound by FDA-approved standards, dietary supplements are regulated differently, resulting in variable quality and increased possibility for adulteration. Internationally, standards for OTC products vary widely. Accessible educational information, improved provider-patient communication, and revision of regulatory policy could improve safety for older adult users of OTC products.

Psychosis in Parkinson's Disease: Current Treatment Options and Impact on Patients and Caregivers

Parkinson's disease (PD) is the second most common neurodegenerative disease seen in older adults after Alzheimer's disease, with increasing prevalence worldwide. Parkinson's disease psychosis (PDP) is a common, non-motor feature of PD, which increases caregiver stress and is a risk-factor for nursing home placement. In this paper we review PDP epidemiology, features, diagnosis, and treatment. PDP most often presents with sequential development of minor and then increasingly complex visual hallucinations mediated by dopaminergic-serotonergic interactions activating the mesolimbic pathway, with contributions from other structures and neurotransmitters. Appropriate evaluation of differential diagnoses for psychosis is vital before diagnosing PDP. Initial treatment should involve non-pharmacologic approaches. If these are unsuccessful and PDP symptoms significantly impact the patient's and or their caregivers' quality of life and functions, then pharmacotherapy is indicated. Pimavanserin is a recently FDA-approved pharmacologic treatment for PDP with a better profile of balanced effectiveness and safety compared to previous use of atypical antipsychotics. Early diagnosis and safer, more effective treatments for PDP should help reduce caregiver burden and enable caregivers to continue to provide care at home versus institutionalization.

Mood Disorders and Anxiety in Parkinson's Disease: Current Concepts

Mood disorders and anxiety significantly impact the prognosis and disease course of Parkinson's disease. Non-motor symptoms of Parkinson's disease such as apathy, anhedonia, and fatigue overlap with diagnostic criteria for anxiety and depression, thus making accurate diagnosis of mood disorders in Parkinson's disease patients difficult. Furthermore, treatment options for mood disorders can produce motor complications leading to poor adherence and impaired quality of life in Parkinson's disease patients. This review aims to clarify the current state of diagnostic and treatment options pertaining to anxiety and mood disorders in Parkinson's disease. It explores both the pharmacologic and non-pharmacologic treatment modalities for various mood disorders in comorbid Parkinson's disease with a brief discussion of the future outlook of the field given the current state of the literature.

Pharmacotherapy for Frontotemporal Dementia

Frontotemporal dementia is a heterogeneous spectrum of neurodegenerative disorders. The neuropathological inclusions are tau proteins, TAR DNA binding protein 43 kDa-TDP-43, or fused in sarcoma-ubiquitinated inclusions. Genetically, several autosomal mutations account for the heritability of the disorder. Phenotypically, frontotemporal dementia can present with a behavioral variant or a language variant called primary progressive aphasia. To date, there are no approved symptomatic or disease-modifying treatments for frontotemporal dementia. Currently used therapies are supported by low-level of evidence (mostly uncontrolled) studies. The off-label use of drugs is also limited by their side-effect profile including an increased risk of confusion, parkinsonian symptoms, and risk of mortality. Emerging disease-modifying treatments currently target the progranulin and the expansion on chromosome 9 open reading frame 72 genes as well as tau deposits. Advancing our understanding of the pathophysiology of the disease and improving the design of future clinical trials are much needed to optimize the chances to obtain positive outcomes.

AVP-786 as a promising treatment option for Alzheimer's Disease including agitation

INTRODUCTION

To date, there is no FDA-approved treatment for agitation in Alzheimer's disease (AD). Medications currently used off-label have modest clinical efficacy and serious side effects.

AREAS COVERED

The authors review the pharmacology, mechanism of action, pharmacokinetics, efficacy, safety and tolerability data of AVP-786, for the treatment of agitation in AD.

EXPERT OPINION

AVP-786, the deuterated form of dextromethorphan/quinidine (AVP-923) which is an approved treatment for Pseudo-Bulbar Affect, emerges as a promising and safe treatment for agitation in AD. Deuteration is an innovative technology that accelerates drug development by conducting faster and less costly clinical trials. No phase II trial was conducted with AVP-786 for the treatment of agitation in AD; the decision to expedite the development of this drug was based on a successful phase II study with AVP-923. Phase III trials with AVP-786 (TRIAD-1 and TRIAD-2) showed mixed findings probably due to the difference in study design. Future phase III studies should use innovative study designs such as the Sequential Parallel Comparison Design to mitigate high placebo response, and the Cohen-Mansfield Agitation Inventory for agitation assessment. They should also include positron emission tomography studies to assess occupancy of various receptors in the brain after AVP-786 is administered.

Doll therapy in dementia: Facts and controversies

BACKGROUND

The management of major neurocognitive disorder (MNCD), formerly known as dementia, is of increasing concern as the elderly population continues to grow. Doll therapy (DT) is a controversial method observed in clinical practice that has both promising benefits and potential ethical concerns. To date, little research has been done on this therapy.

METHODS

A PubMed search was performed using the keywords "dementia," "elderly," "dolls," "doll therapy," and "Alzheimer's disease." A list of pertinent articles was assembled, with irrelevant articles excluded. References from these articles were also reviewed and additional articles were included in the final list.

RESULTS

Research on the utility of DT for patients with MNCD is limited. Current literature suggests that DT may be beneficial in decreasing the use of pharmacologic interventions and alleviating symptoms such as agitation and anxiety. However, most studies consisted of small, unrepresentative sample populations.

CONCLUSIONS

Preliminary studies favor DT as an effective management strategy for behavioral symptoms of MNCD. However, the few existing randomized controlled trials are limited in size and demographics. Further research involving larger, more diverse study samples with more male patients is needed. Additionally, the exact parameters to guide this therapy have not been established and require investigative study.

Testing the Cognitive Reserve Index Questionnaire in an Alzheimer's Disease Population

Background

Alzheimer's disease (AD) is the 6th leading cause of death in the United States and has no cure or progression prevention. The Cognitive Reserve (CR) theory poses that constant brain activity earlier in life later helps to deter pathological changes in the brain, delaying the onset of disease symptoms.

Objective

To determine the reliability and validity of the Cognitive Reserve Index questionnaire (CRIq) in AD patients.

Methods

Primary data collection was done using the CRIq to quantify CR in 90 participants. Correlations and multivariable linear regressions were used to assess reliability and validity.

Results

Reliability was tested in 34 participants. A Pearson correlation coefficient of 0.89 (p < 0.001) indicated a strong positive correlation. Validity was tested in 33 participants. A Pearson correlation coefficient of 0.30 (p = 0.10) indicated an insignificant weak positive correlation.

Conclusion

The CRIq was found reliable. Gaining a better understanding of how CR tools can be used in various cognitive populations will help with the establishment of a research tool that is universally accepted as a true CR measure.

Criteria for Psychosis in Major and Mild Neurocognitive Disorders: International Psychogeriatric Association (IPA) Consensus Clinical and Research Definition

Psychosis is common among individuals with neurocognitive disorders, is difficult to manage, and causes considerable burden and stress to patients and caregivers. Developing effective treatments is a substantial unmet medical need but research has been slowed by the need for updated consensus diagnostic criteria. To address this need, the International Psychogeriatrics Association initiated a process to develop criteria for clinical use, research, and treatment development efforts. The process included clinical, regulatory, and industry stakeholders as well as input from a global network of experts in geriatric psychiatry responding to two surveys (N = 336). Results from the consensus process confirmed that clinicians wanted elaboration of aspects of the definition proposed by Jeste and Finkel in 2000 to ensure that the criteria are applied appropriately. Based on discussions, the survey, and emerging research, criteria were revised to apply to psychosis occurring with all major and mild neurocognitive disorders. Other important changes include providing examples of hallucinations and delusions and clarifying time course, impact, and exclusionary criteria. This definition of psychosis in major and mild neurocognitive disorders can be used to advance many types of research including development of much needed pharmacologic and nonpharmacologic interventions for psychosis in patients with neurocognitive disorders.

Evaluation of rivastigmine in Alzheimer's disease

Dementia is the major cause of mortality and morbidity in older adults, with Alzheimer's disease (AD) being the most common cause. AD has a significant impact on economic and psychosocial status. Cholinesterase inhibitors (ChEIs) are currently the mainstay in the management of AD. Rivastigmine is the only ChEI that inhibits both acetylcholinesterase and butyrylcholinesterase enzymes in the brain. This dual inhibition makes it potentially more effective for AD patients. Its availability as both a transdermal formulation and oral capsule, may improve adherence rates and care giver satisfaction compared with other ChEIs. To date, the data from randomized clinical trials and post marketing observational studies have shown evidence for an impact on cognitive functions in AD with good safety and tolerability.

An update on the efficacy and safety of iloperidone as a schizophrenia therapy

INTRODUCTION

Schizophrenia has a prevalence of approximately 1% in the general population, with 15.2 per 100,000 persons affected. Iloperidone is a second-generation antipsychotic drug approved for the treatment of schizophrenia in adults. It acts primarily by D2/5HT2a receptor antagonism, with greater affinity for the 5HT2a receptor than for the D2 receptor.

AREAS COVERED

This article discusses iloperidone and aims to provide useful information for clinicians to determine which circumstances would best suit the use of iloperidone to treat schizophrenic patients. In this review, the authors briefly discuss schizophrenia and its treatment, before they discuss properties of iloperidone, its indications, approval process, and adverse effects. Finally, the authors review the specific strengths and weaknesses of the medication.

EXPERT OPINION

Iloperidone would be an attractive option in patients who are particularly prone to EPS, or who are showing prominent negative symptoms, as well as cognitive deficits. Its availability only in an oral formulation makes it a better option for patients with good medication adherence, and though it could be useful in patients prone to weight gain or hepatic dysfunction on other second generation antipsychotics, it should be used with caution in patients prone to side effects related to alpha adrenergic blockade.

Deciphering Alzheimer's disease: predicting new therapeutic strategies via improved understanding of biology and pathogenesis

INTRODUCTION

There is no cure for Alzheimer's disease (AD). One explanation may pertain to the need to intervene as early as possible upstream from the accumulation of β-amyloid plaques and tau tangles.

AREAS COVERED

A PUBMED literature search was completed to review the biological or pathological changes at the basis of disease initiation; this includes neuroinflammation, oxidative stress, microbiome changes and glymphatic system dysfunction. Innovative therapeutic strategies based on these mechanisms are also discussed.

EXPERT OPINION

Improved understanding of the pathophysiological mechanisms that underly AD would assist in the identification of drug targets for clinical trials. Furthermore, pharmacokinetic and pharmacodynamic studies are key for the characterization of the properties of disease-modifying drugs and the improvement of their penetration of the blood-brain barrier. Drug targets can be examined at different stages of the disease, hence the importance of selecting and recruiting the appropriate participants, preferably at the earliest stage of AD. New trial designs should be established which primarily involve combination therapies that can work synergistically on common pathways. Going forward, innovative treatment strategies involving nanotechnology, young blood products transfusion and photobiomodulation also offer promise for the future.

Present Algorithms and Future Treatments for Alzheimer's Disease

An estimated 47 million people live with Alzheimer’s disease (AD) and other forms of dementia worldwide. Although no disease-modifying treatments are currently available for AD, earlier diagnosis and proper management of the disease could have considerable impact on patient and caregiver quality of life and functioning. Drugs currently approved for AD treat the cognitive, behavioral, and functional symptoms of the disease and consist of three cholinesterase inhibitors (ChEIs) and the N-methyl-D-aspartate receptor antagonist memantine. Treatment of patients with mild to moderate AD is generally initiated with a ChEI. Patients who show progression of symptoms while on ChEI monotherapy may be switched to another ChEI and/or memantine can be added to the treatment regimen. In recent years, putative disease-modifying therapies have emerged that aim to slow the progression of AD instead of only addressing its symptoms. However, many therapies have failed in clinical trials in patients with established AD, suggesting that, once developed, disease-modifying agents may need to be deployed earlier in the course of illness. The goal of this narrative literature review is to discuss present treatment algorithms and potential future therapies in AD.

Diagnostic Accuracy of the SLU AMSAD Scale for Depression in Older Adults Without Dementia

OBJECTIVES

To evaluate the diagnostic accuracy of a short depression screening tool, the Saint Louis University (SLU) AMSAD depression scale, relative to the Geriatric Depression Scale-15 (GDS-15) and Montgomery-Asberg Depression Rating Scale (MADRS), and in relation to the Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition (DSM-5) criteria for major depressive disorder, in cognitively intact older adults.

DESIGN

Cross-sectional.

SETTING

Outpatient geriatric psychiatry clinic.

PARTICIPANTS

Fifty older adults (aged ≥65 years) without dementia.

MEASUREMENTS

GDS-15, MADRS, SLU AMSAD, and DSM-5 criteria for major depressive disorder were administered.

RESULTS

Total scores (continuous variables) for the GDS-15, MADRS, and SLU AMSAD correlated significantly with the DMS-5 criteria for major depressive disorder (MDD) [area under the curve (AUC) ≥ 0.93, sensitivity = 0.93, and specificity ≥ 0.80]. Optimal cutoffs were 9+ for GDS-15, 18+ for MADRS, and 7+ for SLU AMSAD. When score results were categorized according to their known cutoffs for mild, moderate, and severe depression, AUC values were again high (range = 0.82-0.89), with adequate levels of sensitivity (0.87-0.93) and specificity (0.71-0.86), distinguishing no or mild depression from moderate or severe depression in relation to the DSM-5 diagnostic criteria for MDD.

CONCLUSIONS AND IMPLICATIONS

Strong diagnostic accuracy was shown for the 3 scales. The SLU AMSAD performed as well as the GDS-15 and slightly better than the MADRS. The superiority of the SLU AMSAD is supported by the fact that it encompasses only 5 simply worded, simply scaled items to be used in busy clinical settings.

An evaluation of hydromethylthionine as a treatment option for Alzheimer's disease

INTRODUCTION

Alzheimer's disease (AD) is a major cause of morbidity worldwide and its prevalence is expected to rise. Previous studies involving compounds that target the accumulation of amyloid β protein have been unsuccessful, renewing interest in therapies directed against intracellular deposits of tau proteins. Derived from methylene blue, hydromethylthionine is a tau aggregation inhibitor that recently emerged as a promising disease-modifying treatment for AD.

AREAS COVERED

Herein, the authors cover the chemistry, pharmacodynamics and pharmacokinetics of hydromethylthionine and its oxidized form methylthionine chloride (MTC) that was first studied, as well as clinical efficacy and safety of hydromethylthionine in the treatment of mild to moderate AD.

EXPERT OPINION

Randomized clinical trials with hydromethylthionine failed to show any impact of the doses used on the disease course. Data analysis from a non-randomized cohort showed that a smaller dose of the drug previously thought to be ineffective and used as placebo, prescribed as monotherapy rather than as add-on to AD approved symptomatic therapies may slow cognitive decline. This finding was further confirmed by a pharmacokinetic analysis study showing a dose/response relationship with doses around 16 mg daily. Future trials need to study the pharmacological properties of hydromethylthionine and ascertain the optimal safe and effective dose to be used.

Use of Cholinesterase Inhibitors in Non-Alzheimer's Dementias

Non-Alzheimer's dementias constitute 30% of all dementias and present with major cognitive and behavioral disturbances. Cholinesterase inhibitors improve memory by increasing brain acetylcholine levels and are approved symptomatic therapies for Alzheimer's disease (AD). They have also been investigated in other types of dementias with potential cholinergic dysfunction. There is compelling evidence for a profound cholinergic deficit in Lewy Body dementia (LBD) and Parkinson's disease dementia (PDD), even to a greater extent than AD. However, this deficit is difficult to objectivize in vascular dementia (VaD) given the increased comorbidity with AD. Furthermore, there is minimal to no evidence for cholinergic loss in frontotemporal dementia (FTD). Although cholinesterase inhibitors showed significant improvement in cognitive, behavioral, and functional measures in both LBD and PDD clinical trials, only rivastigmine is approved for PDD, due to the heterogeneity of the scales used, the duration of trials, and the limited sample sizes impacting data interpretation. Similarly, the interpretation of findings in VaD trials are limited by the lack of pre-defined inclusion criteria for 'pure VaD' and the wide heterogeneity of patients enrolled with respect to location and extent of cerebrovascular disease. In FTD patients, cholinesterase inhibitors were mostly associated with worsening of cognitive and behavioral symptoms. In non-AD dementias, cholinesterase inhibitors were well tolerated, with increased reports of mild to moderate cholinergic side effects and a non-significant trend for increased cardio and cerebrovascular events with rivastigmine in VaD, justifying their cautious use on a case-by-case basis, especially when there is evidence for cholinergic deficit.

The cholinergic system in the pathophysiology and treatment of Alzheimer's disease

Cholinergic synapses are ubiquitous in the human central nervous system. Their high density in the thalamus, striatum, limbic system, and neocortex suggest that cholinergic transmission is likely to be critically important for memory, learning, attention and other higher brain functions. Several lines of research suggest additional roles for cholinergic systems in overall brain homeostasis and plasticity. As such, the brain's cholinergic system occupies a central role in ongoing research related to normal cognition and age-related cognitive decline, including dementias such as Alzheimer's disease. The cholinergic hypothesis of Alzheimer's disease centres on the progressive loss of limbic and neocortical cholinergic innervation. Neurofibrillary degeneration in the basal forebrain is believed to be the primary cause for the dysfunction and death of forebrain cholinergic neurons, giving rise to a widespread presynaptic cholinergic denervation. Cholinesterase inhibitors increase the availability of acetylcholine at synapses in the brain and are one of the few drug therapies that have been proven clinically useful in the treatment of Alzheimer's disease dementia, thus validating the cholinergic system as an important therapeutic target in the disease. This review includes an overview of the role of the cholinergic system in cognition and an updated understanding of how cholinergic deficits in Alzheimer's disease interact with other aspects of disease pathophysiology, including plaques composed of amyloid-β proteins. This review also documents the benefits of cholinergic therapies at various stages of Alzheimer's disease and during long-term follow-up as visualized in novel imaging studies. The weight of the evidence supports the continued value of cholinergic drugs as a standard, cornerstone pharmacological approach in Alzheimer's disease, particularly as we look ahead to future combination therapies that address symptoms as well as disease progression.

Rational deprescribing in the elderly

BACKGROUND

Polypharmacy, defined as being prescribed 5 or more medications, has been shown to be associated with a decline in mental and physical functioning in elderly patients. Despite this, elderly patients are currently being prescribed a median of 7 medications, which often causes more harm than benefit, and emphasizes the importance of deprescribing.

METHODS

Five classes of potentially inappropriate medications for the elderly population, especially for the aging brain, are discussed, including anticholinergics, benzodiazepines, antipsychotics, opioids, and proton pump inhibitors. Recommendations regarding these medications were collected from the 2015 Beer's Criteria, the Screening Tool of Older Person's Prescriptions (STOPP) criteria, the Screening Tool to Alert doctors to the Right Treatment (START) criteria, and the Fit fOR The Aged (FORTA) list. The PubMed database was also searched for the most recent evidence regarding prescription patterns, adverse effects, and recommendations regarding discontinuation of these medications in older adults.

RESULTS

Anticholinergics, benzodiazepines, antipsychotics, and opioids were all found to have significant adverse effects in the elderly population. All of the discussed medication classes have been shown to be successfully deprescribable.

CONCLUSIONS

Polypharmacy increases the risk of adverse drug reactions and hospitalizations in geriatric patients. Rational deprescribing of anticholinergics, benzodiazepines, antipsychotics, opioids, and proton pump inhibitors in selected patients may be a good first step to reducing this risk.

Behavioral and psychological symptoms in Alzheimer's dementia and vascular dementia

Behavioral and psychological symptoms of dementia (BPSD) are highly prevalent and represent a significant burden for patients and their caregivers. Early recognition and management of these symptoms is crucial as they are associated with increased risk of institutionalization, impairments in daily functioning, reduced quality of life, and more rapid progression to severe dementia. This chapter will discuss the pathophysiology, proposed diagnostic criteria, clinical features, and management of BPSD, including apathy, depression, agitation/aggression, psychosis, and sleep disturbances. Apathy and depression are the most common overall, and apathy is associated with high symptom severity likely because of its greater persistence. Symptoms such as agitation, aggression, hallucinations, and delusions may be especially distressing and dangerous to patients and caregivers. Nonpharmacologic management should be considered first-line therapy in most cases due to the modest and inconsistent evidence base for pharmacologic agents and greater risk of harm. However, the judicious use of pharmacologic agents may be warranted when symptoms are dangerous and/or severely distressing.

Traumatic Brain Injury, Chronic Traumatic Encephalopathy, and Alzheimer Disease

Traumatic brain injury (TBI) is a major health and economic burden. With increasing aging population, this issue is expected to continue to rise. Neurodegenerative disorders are more common with aging population in general regardless of history of TBI. Recent evidence continues to support a relation between a TBI and neurocognitive decline later in life (such as in athletes and military). This article summarizes the pathologic and clinical effects of TBI (regardless of severity) on the later development of dementia in individuals 65 years or older.

Empathy changes in neurocognitive disorders: A review

BACKGROUND

Empathy can be broadly defined as the ability to understand what others feel (cognitive empathy) and feel what others feel (affective empathy). The capacity to empathize may be impaired in certain major neurocognitive disorders (MNCDs), affecting not only the patient, but also the caregivers.

METHODS

PubMed and Google Scholar databases were searched for studies investigating empathy changes, using an objective scale, in patients with MNCDs.

RESULTS

The Interpersonal Reactivity Index was most commonly used to evaluate empathy in this population. Impairments in cognitive but not affective empathy were found in patients with Alzheimer's disease (AD), and may be attributable to overall cognitive decline. Patients with frontotemporal dementia (FTD) have demonstrated severe deficits in empathy, correlating with greater caregiver burden. Empathy changes in patients with dementia with Lewy bodies, vascular dementia, and Parkinson's disease dementia have not yet been studied. Intranasal oxytocin has emerged as a promising therapeutic approach for empathy loss, but it has not been explored yet in patients with MNCDs.

CONCLUSIONS

Caregivers need to be educated about empathy loss, which is an important part of the disease process in AD and FTD. Future research should further assess empathy changes in other MNCDs, as well as explore novel treatment options in this field.

Memantine ER Maintains Patient Response in Moderate to Severe Alzheimer's Disease: Post Hoc Analyses From a Randomized, Controlled, Clinical Trial of Patients Treated With Cholinesterase Inhibitors

Memantine extended release (ER) significantly outperformed placebo on co-primary endpoints of Clinician's Interview-based Impression of Change Plus Caregiver Input (CIBIC-Plus) and baseline to endpoint changes on the Severe Impairment Battery (SIB) in a 24-week, randomized trial (NCT00322153) in patients with moderate to severe Alzheimer's disease taking a cholinesterase inhibitor (ChEI). A post hoc analysis compared patients receiving memantine ER/ChEI to placebo/ChEI for time to onset of response and if the response was maintained (achieving improvement at weeks 8, 12, or 18 and maintaining through endpoint/week 24) on the SIB, the Neuropsychiatric Inventory (NPI), CIBIC-Plus, and Activities of Daily Living (ADL) using Fisher exact test. A second post hoc analysis compared percentages of patients for all possible combinations of 2 to 4 assessments with either no decline or clinically notable response using Wald χ. Significantly greater percentages of memantine ER/ChEI patients achieved an early response that was maintained on SIB, NPI, and CIBIC-Plus (P<0.05) versus placebo/ChEI. Significantly greater percentages of memantine ER/ChEI-treated patients achieved and maintained a clinically notable response on ADL/NPI, SIB/ADL/NPI, and SIB/ADL/CIBIC-Plus, compared with placebo/ChEI (P<0.05). Memantine ER results in early, maintained improvement in patients with moderate to severe Alzheimer's disease concurrently taking ChEIs, compared with cholinesterase treatment alone.

The role of 5 HT6-receptor antagonists in Alzheimer's disease: an update

INTRODUCTION

Despite recent advances in Alzheimer's disease (AD) research, no breakthrough treatments have been discovered. Cholinesterase inhibitors and the NMDA-receptor antagonist memantine are currently the two approved symptomatic treatments for AD. 5-HT6 receptor antagonism has recently emerged as a promising treatment strategy to improve cognition in AD, with a modest side-effect profile.

AREAS COVERED

5-HT6 receptors, exclusively found in the central nervous system, modulate primarily GABA and glutamate levels, facilitating the secondary release of other neurotransmitters including dopamine, noradrenaline, and acetylcholine, all of which are compromised in AD. This review discusses findings of preclinical and phase I-III clinical trials conducted with three major 5-HT6 receptor antagonists: idalopirdine, intepirdine, and SUVN-502, in the field of AD.

EXPERT OPINION

Despite early positive findings, larger phase-III trials have failed to demonstrate any statistically significant impact on cognition for both idalopirdine and intepirdine, as adjunct to cholinesterase inhibitors. Paradoxically, 5-HT6 receptor agonists have also been shown to have cognitive enhancing properties. Thus, a better understanding of the mechanism of action of the 5-HT6 receptor and its ligands is warranted. Investigating 5-HT6 receptor partial or inverse agonists may be promising in future AD trials.

Recent Progress in the Pharmacotherapy of Alzheimer's Disease

Alzheimer's disease is the most common major neurocognitive disorder with substantial social and economic impacts. This article is an update on current pharmacotherapy, advancements in biomarker use, and drugs in the pipeline for this disease. To date, no new drug has qualified to be added to the current therapeutic arsenal comprising cholinesterase inhibitors and the NMDA receptor antagonist memantine. Drugs in the pipeline include symptomatic therapies that are neurotransmitter-based, but mostly disease-modifying therapies. The latter have yielded disappointing results by focusing mainly on the two pathophysiological hallmarks of Alzheimer's disease: Aβ amyloid deposits and tau protein aggregates forming neurofibrillary tangles. These unsuccessful trials may have resulted from studying these drugs 'too late' relative to Alzheimer's disease onset, in addition to focusing only on the amyloid cascade. In fact, Alzheimer's disease is a complex multifactorial disease. Combining different biomarkers might enhance our ability to identify those patients most at risk of developing the disease, and better predict their conversion rates. Furthermore, adopting an integrative treatment approach by targeting additional pathophysiological pathways in Alzheimer's disease such as inflammation and oxidative stress could be the key to better outcomes in Alzheimer's disease pharmacotherapy research.

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.

Renal concerns relative to the use of lithium in geriatric bipolar disorder patients

BACKGROUND

Lithium is a first-line treatment for bipolar disorder in geriatric patients; however, it has long been associated with potentially significant renal consequences, including chronic kidney disease (CKD).

METHODS

We reviewed the available evidence to characterize the effects of lithium on renal function, provide a consensus on periodic monitoring, and propose criteria for transitioning an older patient with bipolar disorder and renal issues to an alternate medication.

RESULTS

Although the evidence on lithium use, duration, and dosage on progression of CKD and end-stage renal disease in geriatric patients is mixed, there is solid evidence that patients receiving lithium generally have a reduced glomerular filtration rate compared with controls. The current guidelines for monitoring lithium use in geriatric patients are nearly sufficient, but adherence in clinical practice frequently falls short. Alternative medications for bipolar disorder in geriatric patients are generally considered safe and effective, but do not have the strength of evidence that exists in the general adult population.

CONCLUSIONS

Currently, there is no compelling evidence that lithium should be avoided in geriatric patients; however, prudent monitoring strategies are recommended, with a strong consideration of transitioning geriatric patients with poor tolerance to an alternative medication.

Emerging chemical therapies targeting 5-hydroxytryptamine in the treatment of Alzheimer's disease

INTRODUCTION

Alzheimer's disease (AD) is a major neuropsychiatric disorder affecting more than 5 million Americans over age 65. By the year 2050, AD is expected to affect over 30 million. Characterized by neuronal cell death accompanied by the accumulation of neurofibrillary tangles and neuritic plaques, AD results in devastating clinical symptomatology with a lasting psychosocial and financial impact. Studies have shown that the current treatments for AD, cholinesterase inhibitors (ChEI's) and NMDA receptor antagonists, have limited efficacy. The 5-HT-6 receptor antagonists Idalopirdine and Intepirdine have shown the most progress in current clinical trials and warrant consideration as emerging treatments for AD. Areas covered: This review discusses 5-HT6 antagonists currently in clinical trials as potential treatments for AD symptomatology and how 5-HT6 physiology may play a positive role in alleviating AD symptom pathophysiology. A literature search using PubMed was conducted using the terms Idalopirdine, Intepirdine, 5-HT-6 antagonist, and AD as keywords. Clinicaltrials.gov and Alzforum were also used to obtain information on clinical trials. Expert opinion: If current Phase-3 trials are positive, 5-HT6 antagonists such as Idalopirdine and Intepirdine may be considered as supplementary treatments to ChEI's and NMDA receptor antagonists for the symptomatic treatment of AD.

Rapid Depression Assessment in Geriatric Patients

Depression is common in geriatric patients, especially in those with multiple comorbidities and polypharmacy. Depression in older adults is often underdiagnosed and undertreated. Initial screening for depression can easily be accomplished in the waiting room. Yet the clinical interview still remains the gold standard for diagnosing geriatric depression. Key components of the clinical interview are observant watching of the patient for the subtle signs of depression. Clinical interview should be done with sensitivity to the importance of privacy. Illicit substances and medical conditions may significantly contribute. Suicide assessment should be done in a step wise manner.

AVP-786 for the treatment of agitation in dementia of the Alzheimer's type

INTRODUCTION

Agitation is common and distressing in patients with Alzheimer-type dementia, but safe, effective treatments remain elusive. Psychological treatments are first-line options, but they have limited efficacy. Off-label psychotropic medications are frequently used, but they also have limited effectiveness, and their use may have harmful side effects, including death. Areas covered: This review discusses the history leading to the conception of AVP-786 (deuterated (d6)-dextromethorphan/quinidine), its pharmacokinetic and pharmacodynamic profiles and safety issues, together with an overview of recent clinical trials. Data were found in the medical literature, in US and EU clinical trial registries and in information provided by the manufacturer. Expert opinion: AVP-786 is one of six investigational compounds in recent phase III clinical development for agitation in Alzheimer disease (AD). Quinidine and deuteration appear to prolong dextromethorphan's plasma half-life and facilitate brain penetration. The FDA granted fast-track designation to AVP-786 and allowed use of data generated on dextromethorphan-quinidine (AVP-923, Nuedexta®) for regulatory filings. AVP-923 reduced agitation in AD and was well tolerated in a phase II RCT that included more than 200 patients. A phase III clinical development program of AVP-786 for AD agitation was recently initiated. This program is expected to start generating results in July 2018.

Ideomotor limb apraxia as a staging tool in individuals with Alzheimer's disease (ILIAD)

BACKGROUND

Ideomotor apraxia (IMA) is known to affect individuals with Alzheimer's disease (AD). Combined with impaired cognitive function, IMA can support evidence of probable AD. However, apraxia is a condition that is difficult to diagnose. The Postural Knowledge Test (PKT), developed by Mozaz et al, was designed to easily identify limb apraxia in multiple sclerosis yet demonstrated potential utility for AD. ILIAD is a pilot study to investigate correlation between the PKT and Mini-Mental State Examination (MMSE).

METHODS

Participants with mild, moderate, and severe AD were administered the MMSE by 1 examiner, followed by the PKT by a second blinded examiner.

RESULTS

Seventy-seven participants with mild (25), moderate (26), and severe AD (26) met study criteria. Correlation was demonstrated between the MMSE and PKT at 0.835 among all AD groups. Correlation between MMSE and PKT-1 (transitive) and PKT-2 (intransitive) separately was 0.819 and 0.793.

CONCLUSIONS

There is significant correlation between the MMSE (memory loss) and PKT (IMA). This suggests the PKT may be used in conjunction with the MMSE to aid in staging AD and to monitor disease severity. Correlation between the MMSE and separate PKT tests suggests that administration of only 1 test may be necessary clinically, saving valuable time.

A fixed-dose combination of memantine extended-release and donepezil in the treatment of moderate-to-severe Alzheimer's disease

Currently available therapies for the treatment of Alzheimer’s disease (AD) consist of cholinesterase inhibitors (ChEIs), such as donepezil, and the N-methyl-D-aspartate receptor antagonist memantine. In December 2014, the US Food and Drug Administration approved Namzaric™, a once-daily, fixed-dose combination (FDC) of memantine extended-release (ER) and donepezil for patients with moderate-to-severe AD. The FDC capsule is bioequivalent to the coadministered individual drugs, and its bioavailability is similar when taken fasting, with food, or sprinkled onto applesauce. The combination of memantine and ChEIs in moderate-to-severe AD provides additional benefits to ChEI monotherapy across multiple domains and may delay the time to nursing home admission. A dedicated study of memantine ER compared to placebo in patients on a stable dose of a ChEI found statistically significant benefits on cognition and global status but not functioning. Treatment with memantine ER and donepezil is generally well tolerated, although higher doses of ChEIs are associated with more serious adverse events such as vomiting, syncope, and weight loss. Potential advantages of the FDC include a simpler treatment regimen, reduction in pill burden, and the ability to sprinkle the capsule onto soft foods. Patients who may benefit from the FDC include those with significant dysphagia, a history of poor compliance, or limited caregiver interaction. However, available evidence that these advantages would increase treatment adherence and persistence is conflicting, meaning that the added cost of switching patients from generic options to an FDC may not always be justified.

The use of Alprazolam for decreasing problem wandering in geriatric patients

The effects of wandering behavior have been well identified as a problem in providing care for the cognitively impaired. Wandering behavior takes its toll not only on the patient, but also upon the caregiver who is trying to manage and redirect this behavior. This wandering behavior may precipitate admission to a long term care facility where several residents with wandering behaviors present treatment, management, and staff concerns. The costs to the patient have been in the use of traditionalpharmacological options that have potential side effects and iatrogenicity. The costs to the caregiver are stress, frustration, and time constraints in providing care for others. Though the literature discusses wandering, there are varied definitions.

This study attempts to define more precisely which wandering behaviors are perceived as problematic, disruptive and intrusive. Secondly, the study investigates the use of Alprazolam as a less toxic, potentially more effective option for decreasing problem wandering.