1
|
Malin DH, Tsai PH, Campbell JR, Moreno GL, Chapman HL, Suzaki A, Keivan MS, Gibbons KM, Morales ER, Burstein ES, Ward CP. Pimavanserin reverses multiple measures of anxiety in a rodent model of post-traumatic stress disorder. Eur J Pharmacol 2023; 939:175437. [PMID: 36502961 DOI: 10.1016/j.ejphar.2022.175437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 11/08/2022] [Accepted: 11/28/2022] [Indexed: 12/14/2022]
Abstract
Pimavanserin is a highly selective 5-HT2A inverse agonist in current medical use. Prior studies suggest that 5-HT2A serotonin receptors may play a role in anxiety and emotional memory. Therefore, pimavanserin was tested in a rat model of PTSD to determine whether it might ameliorate PTSD-like symptoms. The lifetime prevalence of PTSD is estimated to be 125% higher in women than men. Consequently, in an effort to create a robust model of PTSD that was more representative of human PTSD prevalence, 20-week old female rats of the emotionally hyperreactive Lewis strain were used for these studies. The rats were single-housed and exposed twice to restraint stress coupled with predator odor or to a sham-stressed condition. Twenty days after the second stress or sham-stress exposure, rats were injected with saline alone or with 0.3 or 1.0 mg/kg pimavanserin, doses that were confirmed to substantially block 5-HT2A receptor activity in this study without causing any non-specific behavioral or adverse effects. One hour later, rats were tested for anxiety through acoustic startle response, the elevated plus-maze and three parameters of open field behavior. Five days later, blood was sampled for plasma corticosterone. The stressed/saline-injected rats had higher anxiety scores and corticosterone levels than sham-stressed/saline-injected rats. Pimavanserin significantly and generally dose-dependently reversed these persistent stress effects, but had no significant effect on the behavioral measures in normal, non-stressed rats. These results, consistent with a role for the 5-HT2A receptor, suggest that pimavanserin might have potential to reduce some consequences of traumatic stress.
Collapse
Affiliation(s)
| | | | | | | | | | - Aoi Suzaki
- University of Houston-Clear Lake, United States
| | | | | | | | | | | |
Collapse
|
2
|
Suppression of cocaine relapse-like behaviors upon pimavanserin and lorcaserin co-administration. Neuropharmacology 2020; 168:108009. [DOI: 10.1016/j.neuropharm.2020.108009] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 02/08/2020] [Accepted: 02/11/2020] [Indexed: 12/12/2022]
|
3
|
Dujardin K, Sgambato V. Neuropsychiatric Disorders in Parkinson's Disease: What Do We Know About the Role of Dopaminergic and Non-dopaminergic Systems? Front Neurosci 2020; 14:25. [PMID: 32063833 PMCID: PMC7000525 DOI: 10.3389/fnins.2020.00025] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 01/10/2020] [Indexed: 12/13/2022] Open
Abstract
Besides the hallmark motor symptoms (rest tremor, hypokinesia, rigidity, and postural instability), patients with Parkinson’s disease (PD) have non-motor symptoms, namely neuropsychiatric disorders. They are frequent and may influence the other symptoms of the disease. They have also a negative impact on the quality of life of patients and their caregivers. In this article, we will describe the clinical manifestations of the main PD-related behavioral disorders (depression, anxiety disorders, apathy, psychosis, and impulse control disorders). We will also provide an overview of the clinical and preclinical literature regarding the underlying mechanisms with a focus on the role of the dopaminergic and non-dopaminergic systems.
Collapse
Affiliation(s)
- Kathy Dujardin
- Inserm U1171 Degenerative and Vascular Cognitive Disorders, Lille University Medical Center, Lille, France
| | - Véronique Sgambato
- CNRS, Institut des Sciences Cognitives Marc Jeannerod, UMR 5229, Lyon University, Bron, France
| |
Collapse
|
4
|
Szulczyk D, Bielenica A, Kędzierska E, Leśniak A, Pawłowska A, Bujalska-Zadrożny M, Saccone I, Sparaco R, Fiorino F, Savchenko O, Struga M. G protein-coupled receptor binding and pharmacological evaluation of indole-derived thiourea compounds. Arch Pharm (Weinheim) 2019; 353:e1900218. [PMID: 31782553 DOI: 10.1002/ardp.201900218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 10/18/2019] [Accepted: 11/15/2019] [Indexed: 12/16/2022]
Abstract
Four 2-(1H-indol-3-yl)ethylthiourea derivatives were prepared by condensation of 2-(1H-indol-3-yl)ethanamine with the corresponding aryl/alkylisothiocyanates in a medium-polarity solvent. Their structures were confirmed by spectral techniques, and the molecular structure of 3 was determined by X-ray crystal analysis. For all derivatives, the binding affinities at the 5-HT2A and 5-HT2C receptors, as well as their functional activities at the 5-HT1A and D2 receptors, were determined. The arylthioureas 1 and 4 were the most active at the 5-HT1A receptor, showing, at the same time, significant selectivity over the studied 5-HT2 and D2 receptor subtypes. The compounds were tested for their pharmacological activities within the central nervous system in relevant mouse models. The involvement of the serotonergic system in the activity of 1 and 4 was indicated. The antinociceptive action of 4 was linked to its anti-inflammatory activity.
Collapse
Affiliation(s)
- Daniel Szulczyk
- Department of Biochemistry, Medical University of Warsaw, Warszawa, Poland
| | - Anna Bielenica
- Department of Biochemistry, Medical University of Warsaw, Warszawa, Poland
| | - Ewa Kędzierska
- Department of Pharmacology and Pharmacodynamics, Medical University of Lublin, Lublin, Poland
| | - Anna Leśniak
- Department of Pharmacodynamics, Medicine Division, Centre for Preclinical Research and Technology, Faculty of Pharmacy with the Laboratory, Medical University of Warsaw, Warszawa, Poland
| | - Agata Pawłowska
- Department of Pharmacodynamics, Medicine Division, Centre for Preclinical Research and Technology, Faculty of Pharmacy with the Laboratory, Medical University of Warsaw, Warszawa, Poland
| | - Magdalena Bujalska-Zadrożny
- Department of Pharmacodynamics, Medicine Division, Centre for Preclinical Research and Technology, Faculty of Pharmacy with the Laboratory, Medical University of Warsaw, Warszawa, Poland
| | - Irene Saccone
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Rosa Sparaco
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | | | | | - Marta Struga
- Department of Biochemistry, Medical University of Warsaw, Warszawa, Poland
| |
Collapse
|
5
|
Inverse agonists of the 5-HT2A receptor reduce nicotine withdrawal signs in rats. Neurosci Lett 2019; 713:134524. [DOI: 10.1016/j.neulet.2019.134524] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 08/30/2019] [Accepted: 09/27/2019] [Indexed: 11/23/2022]
|
6
|
Price AE, Brehm VD, Hommel JD, Anastasio NC, Cunningham KA. Pimavanserin and Lorcaserin Attenuate Measures of Binge Eating in Male Sprague-Dawley Rats. Front Pharmacol 2018; 9:1424. [PMID: 30581386 PMCID: PMC6293203 DOI: 10.3389/fphar.2018.01424] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 11/19/2018] [Indexed: 01/08/2023] Open
Abstract
Binge eating disorder (BED) is characterized by dysregulated feeding and reward-related processes, and treatment is often challenged by limited therapeutic options. The serotonin (5-HT) 5-HT2A receptor (5-HT2AR) and 5-HT2CR are implicated in both feeding-related and reward-related behaviors and are thus poised to regulate BED-related behaviors. The purpose of this study was to assess the efficacy of the FDA-approved medications pimavanserin, a 5-HT2AR antagonist/inverse agonist, and lorcaserin, a 5-HT2CR agonist, in a rodent model of binge eating. The effects of pimavanserin (0.3–3.0 mg/kg), lorcaserin (0.25–1.0 mg/kg), and the lowest effective dose of pimavanserin (0.3 mg/kg) plus lorcaserin (1.0 mg/kg) were tested in a high-fat food (HFF) intermittent access binge eating model in adult male Sprague-Dawley rats (n = 64). We assessed three measures related to binge eating – binge episode occurrence, binge intake, and weight gain associated with HFF access. Pimavanserin decreased binge intake and weight gain associated with HFF access, but did not prevent binge episode occurrence. Lorcaserin decreased binge intake, but did not prevent binge episode occurrence or weight gain associated with HFF access. Combined pimavanserin plus lorcaserin prevented binge episode occurrence in addition to decreasing binge intake and weight gain associated with HFF access. These preclinical findings in male rats suggest that pimavanserin and lorcaserin may be effective in treating patients with BED. Our studies further indicate that administration of one or both drugs may be more effective in certain sub-populations of patients with BED because of the unique profile each treatment elicits. These data support future assessment in clinical populations with BED.
Collapse
Affiliation(s)
- Amanda E Price
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX, United States
| | - Victoria D Brehm
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX, United States
| | - Jonathan D Hommel
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX, United States.,Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, United States
| | - Noelle C Anastasio
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX, United States.,Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, United States
| | - Kathryn A Cunningham
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX, United States.,Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, United States
| |
Collapse
|
7
|
Charvin D, Medori R, Hauser RA, Rascol O. Therapeutic strategies for Parkinson disease: beyond dopaminergic drugs. Nat Rev Drug Discov 2018; 17:804-822. [PMID: 30262889 DOI: 10.1038/nrd.2018.136] [Citation(s) in RCA: 144] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Existing therapeutic strategies for managing Parkinson disease (PD), which focus on addressing the loss of dopamine and dopaminergic function linked with degeneration of dopaminergic neurons, are limited by side effects and lack of long-term efficacy. In recent decades, research into PD pathophysiology and pharmacology has focused on understanding and tackling the neurodegenerative processes and symptomology of PD. In this Review, we discuss the challenges associated with the development of novel therapies for PD, highlighting emerging agents that aim to target cell death, as well as new targets offering a symptomatic approach to managing features and progression of the disease.
Collapse
Affiliation(s)
| | | | - Robert A Hauser
- Department of Neurology, University of South Florida, Tampa, FL, USA
| | - Olivier Rascol
- Centre d'Investigation Clinique CIC1436, Services de Neurologie et de Pharmacologie Clinique, Réseau NS-PARK/FCRIN et Centre COEN NeuroToul, CHU de Toulouse, INSERM, University of Toulouse 3, Toulouse, France
| |
Collapse
|
8
|
Wang S, Wang Y, Gao S, Zhang Y, Wang H, Zhao L, Bi K, Wang S, Chen X. Development of a UPLC-MS/MS method for determination of pimavanserin tartrate in rat plasma: Application to a pharmacokinetic study. J Pharm Anal 2017; 7:406-410. [PMID: 29404067 PMCID: PMC5790751 DOI: 10.1016/j.jpha.2017.07.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Revised: 02/24/2017] [Accepted: 07/07/2017] [Indexed: 11/30/2022] Open
Abstract
A simple, rapid and sensitive method based on an ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) has been developed and validated for the determination of pimavanserin in rat plasma. The analyte was extracted by protein precipitation with methanol and separated on an ACQUITY BEH C18 column (100 × 2.1 mm, 1.7 µm; Waters, USA), with an isocratic elution of acetonitrile-water containing 10 mM ammonium acetate (70:30, v/v), at a flow rate of 0.2 mL/min for 2.5 min. The analyte and clarithromycin (the internal standard) were detected and quantified in positive ion mode using multiple reaction monitoring transitions at m/z 428.2 → 223.0 for pimavanserin and m/z 748.5 → 589.5 for clarithromycin. Relative coefficient (r) for the calibration curve was more than 0.9980. The intra-day and inter-day precisions (relative standard deviation, RSD%) were less than 13.3% and 10.5%, respectively, and the accuracy (relative error, RE%) was within ± 11.5%. The analytical method was successfully applied to a routine pharmacokinetic study of pimavanserin in rats after oral administration at the dose of 10 mg/kg.
Collapse
Affiliation(s)
- Shixiao Wang
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Yang Wang
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Shuang Gao
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Yuanyuan Zhang
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Hanpei Wang
- Key Laboratory of Structure-Based Drugs Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Longshan Zhao
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Kaishun Bi
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Shaojie Wang
- Key Laboratory of Structure-Based Drugs Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, China
| | - Xiaohui Chen
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang 110016, China
| |
Collapse
|
9
|
Yuan M, Sperry L, Malhado‐Chang N, Duffy A, Wheelock V, Farias S, O'Connor K, Olichney J, Shahlaie K, Zhang L. Atypical antipsychotic therapy in Parkinson's disease psychosis: A retrospective study. Brain Behav 2017. [PMID: 28638698 PMCID: PMC5474696 DOI: 10.1002/brb3.639] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVE Parkinson's disease psychosis (PDP) is a frequent complication of idiopathic Parkinson's disease (iPD) with significant impact on quality of life and association with poorer outcomes. Atypical antipsychotic drugs (APDs) are often used for the treatment of PDP; however, their use is often complicated by adverse drug reactions (ADRs). In this study, we present patients with PDP who were treated with the most commonly used atypical antipsychotic agents and review their respective ADRs. METHODS A retrospective study was carried out to include a total of 45 patients with iPD who visited a movement disorders clinic between 2006 and 2015. All PDP patients treated with atypical APDs were included in the analysis for their specific ADRs. RESULTS Forty-five iPD patients (mean age of onset: 62.67 ± 9.86 years) were included, of those 10 patients had psychosis (mean age of onset: 76.80 ± 4.61 years). Of the 45 patients, 22.2% were found to have psychotic symptoms, of whom 70% had hallucinations, 20% had delusions, and 10% illusions. Seventy percent of psychotic symptoms occurred after ten or more years from diagnosis of iPD. PDP patients were treated with quetiapine, olanzapine, and risperidone separately or in combination, all of which were found to have certain ADRs. LIMITATIONS This study was limited by its retrospective study design and small sample size and with likely selection bias. CONCLUSIONS The prevalence of PDP is relatively high in older patients with iPD. The uses of the currently available atypical APDs in this patient population are often complicated by ADRs. The selective 5-HT 2A inverse agonist, pimavanserin, could be a better alternative in the treatment of PDP.
Collapse
Affiliation(s)
- Mei Yuan
- Department of NeurologyThe Second Affiliated HospitalUniversity Of South ChinaHengyangHunanChina
- Department of NeurologyUC Davis Medical CenterSacramentoCAUSA
| | - Laura Sperry
- Department of NeurologyUC Davis Medical CenterSacramentoCAUSA
| | | | - Alexandra Duffy
- Department of NeurologyUC Davis Medical CenterSacramentoCAUSA
| | - Vicki Wheelock
- Department of NeurologyUC Davis Medical CenterSacramentoCAUSA
| | - Sarah Farias
- Department of NeurologyUC Davis Medical CenterSacramentoCAUSA
| | - Kevin O'Connor
- Center for Neuroscience and Department of Neurobiology, Physiology and BehaviorUC Davis Medical CenterUC DavisSacramentoCAUSA
| | - John Olichney
- Center for Neuroscience and Department of Neurobiology, Physiology and BehaviorUC Davis Medical CenterUC DavisSacramentoCAUSA
| | - Kiarash Shahlaie
- Department of Neurologic SurgeryUC Davis Medical CenterSacramentoCAUSA
| | - Lin Zhang
- Department of NeurologyUC Davis Medical CenterSacramentoCAUSA
| |
Collapse
|
10
|
Hutson PH, Clark JA, Cross AJ. CNS Target Identification and Validation: Avoiding the Valley of Death or Naive Optimism? Annu Rev Pharmacol Toxicol 2016; 57:171-187. [PMID: 27575715 DOI: 10.1146/annurev-pharmtox-010716-104624] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
There are many challenges along the path to the approval of new drugs to treat CNS disorders, one of the greatest areas of unmet medical need with a large societal burden and health-care impact. Unfortunately, over the past two decades, few CNS drug approvals have succeeded, leading many pharmaceutical companies to deprioritize this therapeutic area. The reasons for the failures in CNS drug discovery are likely to be multifactorial. However, selecting the most biologically plausible molecular targets that are relevant to the disorder is a critical first step to improve the probability of success. In this review, we outline previous methods for identifying and validating novel targets for CNS drug discovery, and, cognizant of previous failures, we discuss potential new strategies that may improve the probability of success of developing novel treatments for CNS disorders.
Collapse
Affiliation(s)
- P H Hutson
- Neurobiology, CNS Discovery, Teva Pharmaceuticals, West Chester, Pennsylvania 19380;
| | - J A Clark
- Intramural Research Program, National Institute of Mental Health, Bethesda, Maryland 20892;
| | - A J Cross
- Neuroscience Innovative Medicines, AstraZeneca, Cambridge, Massachusetts 01239;
| |
Collapse
|
11
|
Martinez-Ramirez D, Okun MS, Jaffee MS. Parkinson's disease psychosis: therapy tips and the importance of communication between neurologists and psychiatrists. Neurodegener Dis Manag 2016; 6:319-30. [PMID: 27408981 PMCID: PMC5066136 DOI: 10.2217/nmt-2016-0009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 06/03/2016] [Indexed: 12/17/2022] Open
Abstract
Parkinson's disease (PD) is a chronic and complex neurodegenerative disorder resulting in a mixture of motor and nonmotor symptoms. Psychosis develops in around 60% of PD patients during and can be one of the most challenging nonmotor symptoms. PD psychosis is considered the single greatest precipitant for nursing home placement. PD psychosis is an independent predictor of increased mortality, and there is no 'ideal' or universal treatment strategy. The treatment approach to PD psychosis should be tailored and individualized for each patient. In this review, we will discuss PD psychosis and provide practical treatment considerations for neurologists, psychiatrists and other healthcare professionals. We stress the importance of real-time communication between members of the healthcare team.
Collapse
Affiliation(s)
- Daniel Martinez-Ramirez
- Department of Neurology, University of Florida College of Medicine, Center for Movement Disorders & Neurorestoration, Gainesville, FL 32607, USA
| | - Michael S Okun
- Department of Neurology, University of Florida College of Medicine, Center for Movement Disorders & Neurorestoration, Gainesville, FL 32607, USA
| | - Michael S Jaffee
- Department of Neurology, University of Florida College of Medicine, Center for Movement Disorders & Neurorestoration, Gainesville, FL 32607, USA
| |
Collapse
|
12
|
Mechanism of action of pimavanserin in Parkinson's disease psychosis: targeting serotonin 5HT2A and 5HT2C receptors. CNS Spectr 2016; 21:271-5. [PMID: 27503570 DOI: 10.1017/s1092852916000407] [Citation(s) in RCA: 195] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Pimavanserin, a novel agent approved for the treatment of Parkinson's disease psychosis, has potent actions as an antagonist/inverse agonist at serotonin 5HT2A receptors and less potent antagonist/inverse agonist actions at 5HT2C receptors.
Collapse
|
13
|
On the discovery and development of pimavanserin: a novel drug candidate for Parkinson's psychosis. Neurochem Res 2014; 39:2008-17. [PMID: 24682754 PMCID: PMC4172996 DOI: 10.1007/s11064-014-1293-3] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2013] [Revised: 03/19/2014] [Accepted: 03/21/2014] [Indexed: 12/30/2022]
Abstract
Parkinson’s disease psychosis (PDP) is a condition that may develop in up to 60 % of Parkinson’s patients, and is a major reason for nursing home placement for those affected. There are no FDA approved drugs for PDP but low doses of atypical anti-psychotic drugs (APDs) are commonly prescribed off-label. Only low-dose clozapine has shown efficacy in randomized controlled trials, but all APDs have black box warnings related to the increased mortality and morbidity when used in elderly demented patients. Using molecular pharmacological profiling of a large collection of marketed drugs, we discovered that potent inverse agonist activity against 5-HT2A serotonin receptors was a common feature of atypical APDs, especially the atypical APDs used to treat PDP. Since low-dose clozapine therapy selectively blocks this receptor, it was hypothesized that a highly selective 5-HT2A receptor inverse agonist might provide good symptom control in patients suffering from PDP, with a greatly improved safety and tolerability profile. A high throughput screening and subsequent chemical lead optimization campaign to develop potent, selective 5-HT2A receptor inverse agonists was launched, eventually resulting in the discovery of pimavanserin. Pimavanserin displays nanomolar potency as a 5-HT2A receptor inverse agonist, selectivity for 5-HT2A over 5-HT2C receptors, and no meaningful activity at any other G-protein coupled receptor. It demonstrated robust activity in preclinical models of schizophrenia and PDP, and did not worsen motoric symptoms, in contrast to the APDs tested. In a Phase III clinical trial, pimavanserin showed highly significant benefits in the primary endpoint, the scale for assessment of positive symptoms-PD, a scale adapted for use in PDP. In addition, improvements in all other efficacy endpoints, including physician’s clinical global impression, caregiver burden, night-time sleep quality and daytime wakefulness, were seen. Pimavanserin demonstrated good safety and tolerability and did not worsen motoric symptoms as assessed by the unified Parkinson’s disease rating scale parts II and III. An open-label extension study has further demonstrated that pimavanserin is safe and well-tolerated with long-term use. Pimavanserin may therefore offer a viable treatment option for patients suffering from PDP.
Collapse
|
14
|
Goldman JG, Holden S. Treatment of psychosis and dementia in Parkinson's disease. Curr Treat Options Neurol 2014; 16:281. [PMID: 24464490 DOI: 10.1007/s11940-013-0281-2] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OPINION STATEMENT Parkinson's disease (PD) has been increasingly recognized as having a multitude of nonmotor symptoms including psychosis, cognitive impairment and dementia, mood disturbances, fatigue, apathy, and sleep disorders. Psychosis and dementia, in particular, greatly affect quality of life for both patients and caregivers and are associated with poor outcomes. Safe and effective treatment options for psychosis and dementia in PD are much needed. Antipsychotics with dopamine-blocking properties can worsen parkinsonian motor features and have been associated with increased morbidity and mortality in elderly, dementia patients. For treating PD psychosis, a first step would be eliminating confounding variables, such as delirium, infections, or toxic-metabolic imbalances, followed by simplifying parkinsonian medications as tolerated. If additional treatment is warranted after such interventions, clozapine or quetiapine can be implemented at the low dose levels typically needed by PD patients. Although quetiapine is easy-to-use in clinical settings, does not require blood count monitoring like clozapine, and is anecdotally beneficial, it remains "investigational" in evidence-based medicine reviews. Though not currently available, the novel 5-HT2a inverse agonist, pimavanserin has shown promise in the treatment of PD psychosis. Current treatments for PD dementia are mostly derived from those utilized in Alzheimer's disease, focusing mainly on cholinesterase inhibitors and memantine, a NMDA receptor antagonist. Rivastigmine, the only Food and Drug Administration approved medication for PD dementia, is a reasonable first choice. Other cholinesterase inhibitors and memantine have not yet achieved recommendation status in evidence-based medicine reviews but are well tolerated in studies of PD dementia patients. At present, there are no approved treatments for mild cognitive impairment in PD, but rasagiline, a selective MAO-B inhibitor, and atomoxetine, a serotonin norepinephrine reuptake inhibitor, have been recently studied. Nonpharmacological interventions, including cognitive therapy, physical activity, music and art therapy, and noninvasive brain stimulation techniques, may be promising options for PD cognitive impairment but await rigorous study.
Collapse
Affiliation(s)
- Jennifer G Goldman
- Department of Neurological Sciences, Section of Parkinson Disease and Movement Disorders, Rush University Medical Center, 1725 W. Harrison Street, Suite 755, Chicago, IL, 60612, USA,
| | | |
Collapse
|