1
|
Knöchel J, Bergenholm L, Ibrahim E, Kechagias S, Hansson S, Liljeblad M, Nasr P, Carlsson B, Ekstedt M, Ueckert S. A Markov model of fibrosis development in nonalcoholic fatty liver disease predicts fibrosis progression in clinical cohorts. CPT Pharmacometrics Syst Pharmacol 2023; 12:2038-2049. [PMID: 37750001 PMCID: PMC10725269 DOI: 10.1002/psp4.13052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 08/28/2023] [Accepted: 09/06/2023] [Indexed: 09/27/2023] Open
Abstract
Disease progression in nonalcoholic steatohepatitis (NASH) is highly heterogenous and remains poorly understood. Fibrosis stage is currently the best predictor for development of end-stage liver disease and mortality. Better understanding and quantifying the impact of factors affecting NASH and fibrosis is essential to inform a clinical study design. We developed a population Markov model to describe the transition probability between fibrosis stages and mortality using a unique clinical nonalcoholic fatty liver disease cohort with serial biopsies over 3 decades. We evaluated covariate effects on all model parameters and performed clinical trial simulations to predict the fibrosis progression rate for external clinical cohorts. All parameters were estimated with good precision. Age and diagnosis of type 2 diabetes (T2D) were found to be significant predictors in the model. Increase in hepatic steatosis between visits was the most important predictor for progression of fibrosis. Fibrosis progression rate (FPR) was twofold higher for fibrosis stages 0 and 1 (F0-1) compared to fibrosis stage 2 and 3 (F2-3). A twofold increase in FPR was observed for T2D. A two-point steatosis worsening increased the FPR 11-fold. Predicted fibrosis progression was in good agreement with data from external clinical cohorts. Our fibrosis progression model shows that patient selection, particularly initial fibrosis stage distribution, can significantly impact fibrosis progression and as such the window for assessing drug efficacy in clinical trials. Our work highlights the increase in hepatic steatosis as the most important factor in increasing FPR, emphasizing the importance of well-defined lifestyle advise for reducing variability in NASH progression during clinical trials.
Collapse
Affiliation(s)
- Jane Knöchel
- Clinical Pharmacology and Quantitative PharmacologyClinical Pharmacology & Safety Sciences, R&D, AstraZenecaGothenburgSweden
| | - Linnéa Bergenholm
- DMPK, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZenecaGothenburgSweden
| | - Eman Ibrahim
- Department of PharmacyUppsala UniversityUppsalaSweden
| | - Stergios Kechagias
- Department of Health, Medicine, and Caring SciencesLinköping UniversityLinköpingSweden
| | - Sara Hansson
- Translational Science and Experimental Medicine, Research and Early DevelopmentCardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZenecaGothenburgSweden
| | - Mathias Liljeblad
- Translational Science and Experimental Medicine, Research and Early DevelopmentCardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZenecaGothenburgSweden
| | - Patrik Nasr
- Department of Health, Medicine, and Caring SciencesLinköping UniversityLinköpingSweden
| | - Björn Carlsson
- Translational Science and Experimental Medicine, Research and Early DevelopmentCardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZenecaGothenburgSweden
| | - Mattias Ekstedt
- Department of Health, Medicine, and Caring SciencesLinköping UniversityLinköpingSweden
| | - Sebastian Ueckert
- Clinical Pharmacology and Quantitative PharmacologyClinical Pharmacology & Safety Sciences, R&D, AstraZenecaGothenburgSweden
| |
Collapse
|
2
|
Galkin M, Topcheva O, Priss A, Borisova T, Shvadchak VV. Dopamine-Induced Oligomers of α-Synuclein Inhibit Amyloid Fibril Growth and Show No Toxicity. ACS Chem Neurosci 2023. [PMID: 37162160 DOI: 10.1021/acschemneuro.2c00815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023] Open
Abstract
Parkinson's disease is characterized by the selective death of dopaminergic neurons in the midbrain and accumulation of amyloid fibrils composed of α-synuclein (αSyn). Current treatment involves approaches that compensate the death of dopaminergic neurons by increasing the dopamine levels in remaining cells. However, dopamine can interact with αSyn and produce oligomeric species which were reported to be toxic in many models. We studied formation of dopamine-induced αSyn oligomers and their effect on the αSyn aggregation. Using the Thioflavin T kinetic assay, we have shown that small oligomers efficiently inhibit αSyn fibrillization by binding to fibril ends and blocking the elongation. Moreover, all the fractions of oligomer species proved to be nontoxic in the differentiated SH-SY5Y cell model and showed negligible neurotoxicity on isolated rat synaptosomes. The observed inhibition is an important insight in understanding of dopamine-enhancing therapy on Parkinson's disease progression and explains the absence of pathology enhancement.
Collapse
Affiliation(s)
- Maksym Galkin
- Laboratory of Chemical Biology, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences Flemingovo náměstí 542/2, 160 00 Prague 6, Czech Republic
| | - Oleksandra Topcheva
- Laboratory of Chemical Biology, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences Flemingovo náměstí 542/2, 160 00 Prague 6, Czech Republic
| | - Anastasiia Priss
- Laboratory of Chemical Biology, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences Flemingovo náměstí 542/2, 160 00 Prague 6, Czech Republic
| | - Tatiana Borisova
- Department of Neurochemistry, Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, 9 Leontovycha Street, Kyiv 01054, Ukraine
| | - Volodymyr V Shvadchak
- Laboratory of Chemical Biology, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences Flemingovo náměstí 542/2, 160 00 Prague 6, Czech Republic
- Department of Biochemistry and Biotechnology, Vasyl Stefanyk Precarpathian National University, 57 Shevchenko Str., Ivano-Frankivsk 76018, Ukraine
| |
Collapse
|
3
|
Interactions of dopamine, iron, and alpha-synuclein linked to dopaminergic neuron vulnerability in Parkinson's disease and neurodegeneration with brain iron accumulation disorders. Neurobiol Dis 2022; 175:105920. [DOI: 10.1016/j.nbd.2022.105920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 10/21/2022] [Accepted: 11/04/2022] [Indexed: 11/08/2022] Open
|
4
|
D'Agate S, Wilson T, Adalig B, Manyak M, Palacios-Moreno JM, Chavan C, Oelke M, Roehrborn C, Della Pasqua O. Model-based meta-analysis of individual International Prostate Symptom Score trajectories in patients with benign prostatic hyperplasia with moderate or severe symptoms. Br J Clin Pharmacol 2020; 86:1585-1599. [PMID: 32144791 PMCID: PMC7373698 DOI: 10.1111/bcp.14268] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2019] [Revised: 02/01/2020] [Accepted: 02/11/2020] [Indexed: 12/01/2022] Open
Abstract
Aims International Prostate Symptom Score (IPSS) is a marker of lower urinary tract symptoms (LUTS) deterioration or improvement in benign prostate hyperplasia (BPH). Whereas changes in IPSS relative to baseline have been used as endpoints in clinical trials, little attention has been given to the time course of symptoms. The current investigation aimed to develop a drug‐disease model to describe individual IPSS trajectories in moderate and severe BPH patients. Methods A model‐based meta‐analytical approach was used including data from 10 238 patients enrolled into Phase III and IV studies receiving placebo, tamsulosin, dutasteride or combination therapy over a period of up to 4 years. Model predictive performance was assessed using statistical and graphical criteria. Subsequently, simulations were performed to illustrate the implications of treatment with drugs showing symptomatic and disease‐modifying properties in patients with varying disease progression rates. Results Improvement and worsening of IPSS could be characterized by a model including a sigmoid function which disentangles drug effects from placebo and varying disease progression rates on IPSS. Mean estimate (95% confidence intervals) for the disease progression rate was 0.319 (0.271–0.411) month−1. Treatment effect on IPSS (DELTA) was found to be 0.0605, 0.0139 and 0.0310 month−1 for placebo, tamsulosin and combination therapy, respectively. In addition, it appears that individual trajectories can be clustered together into different phenotypes describing the underlying disease progression rate (i.e. slow, moderate and fast progressors). Conclusions The availability of a drug‐disease model enables the evaluation of interindividual differences in disease progression rate, deterioration of symptoms and treatment effects on LUTS/BPH.
Collapse
Affiliation(s)
- Salvatore D'Agate
- Clinical Pharmacology and Therapeutics Group, University College London, London, UK
| | | | - Burkay Adalig
- Classic & Established Products, GSK, Istanbul, Turkey
| | - Michael Manyak
- Classic & Established Products, GSK, Washington, DC, USA
| | | | | | - Matthias Oelke
- Department of Urology, St Antonius Hospital, Gronau, Germany
| | - Claus Roehrborn
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Oscar Della Pasqua
- Clinical Pharmacology and Therapeutics Group, University College London, London, UK.,Clinical Pharmacology Modelling and Simulation, GSK, Uxbridge, Middlesex, UK
| |
Collapse
|
5
|
Lawton M, Ben-Shlomo Y, May MT, Baig F, Barber TR, Klein JC, Swallow DMA, Malek N, Grosset KA, Bajaj N, Barker RA, Williams N, Burn DJ, Foltynie T, Morris HR, Wood NW, Grosset DG, Hu MTM. Developing and validating Parkinson's disease subtypes and their motor and cognitive progression. J Neurol Neurosurg Psychiatry 2018; 89:1279-1287. [PMID: 30464029 PMCID: PMC6288789 DOI: 10.1136/jnnp-2018-318337] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 06/05/2018] [Accepted: 06/13/2018] [Indexed: 01/30/2023]
Abstract
OBJECTIVES To use a data-driven approach to determine the existence and natural history of subtypes of Parkinson's disease (PD) using two large independent cohorts of patients newly diagnosed with this condition. METHODS 1601 and 944 patients with idiopathic PD, from Tracking Parkinson's and Discovery cohorts, respectively, were evaluated in motor, cognitive and non-motor domains at the baseline assessment. Patients were recently diagnosed at entry (within 3.5 years of diagnosis) and were followed up every 18 months. We used a factor analysis followed by a k-means cluster analysis, while prognosis was measured using random slope and intercept models. RESULTS We identified four clusters: (1) fast motor progression with symmetrical motor disease, poor olfaction, cognition and postural hypotension; (2) mild motor and non-motor disease with intermediate motor progression; (3) severe motor disease, poor psychological well-being and poor sleep with an intermediate motor progression; (4) slow motor progression with tremor-dominant, unilateral disease. Clusters were moderately to substantially stable across the two cohorts (kappa 0.58). Cluster 1 had the fastest motor progression in Tracking Parkinson's at 3.2 (95% CI 2.8 to 3.6) UPDRS III points per year while cluster 4 had the slowest at 0.6 (0.1-1.1). In Tracking Parkinson's, cluster 2 had the largest response to levodopa 36.3% and cluster 4 the lowest 28.8%. CONCLUSIONS We have found four novel clusters that replicated well across two independent early PD cohorts and were associated with levodopa response and motor progression rates. This has potential implications for better understanding disease pathophysiology and the relevance of patient stratification in future clinical trials.
Collapse
Affiliation(s)
- Michael Lawton
- Department of Population Health Sciences, University of Bristol, Bristol, UK
| | - Yoav Ben-Shlomo
- Department of Population Health Sciences, University of Bristol, Bristol, UK
| | - Margaret T May
- Department of Population Health Sciences, University of Bristol, Bristol, UK
| | - Fahd Baig
- Nuffield Department of Clinical Neurosciences, Division of Clinical Neurology, University of Oxford, Oxford, UK.,Oxford Parkinson's Disease Centre, University of Oxford, Oxford, UK
| | - Thomas R Barber
- Nuffield Department of Clinical Neurosciences, Division of Clinical Neurology, University of Oxford, Oxford, UK.,Oxford Parkinson's Disease Centre, University of Oxford, Oxford, UK
| | - Johannes C Klein
- Nuffield Department of Clinical Neurosciences, Division of Clinical Neurology, University of Oxford, Oxford, UK.,Oxford Parkinson's Disease Centre, University of Oxford, Oxford, UK
| | - Diane M A Swallow
- Institute of Applied Health Sciences, University of Aberdeen, Aberdeen, UK
| | - Naveed Malek
- Department of Neurology, Institute of Neurological Sciences, Glasgow, UK
| | | | - Nin Bajaj
- Department of Neurology, Queen's Medical Centre, Nottingham, UK
| | - Roger A Barker
- Clinical Neurosciences, John van Geest Centre for Brain Repair, Cambridge, UK
| | - Nigel Williams
- Cardiff University, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff, UK
| | - David J Burn
- Faculty of Medical Sciences, Newcastle University, Newcastle, UK
| | - Thomas Foltynie
- Sobell Department of Motor Neuroscience, UCL Institute of Neurology, London, UK
| | - Huw R Morris
- Department of Clinical Neuroscience, UCL Institute of Neurology, London, UK
| | - Nicholas W Wood
- Department of Molecular Neuroscience, UCL Institute of Neurology, London, UK
| | - Donald G Grosset
- Department of Neurology, Institute of Neurological Sciences, Glasgow, UK
| | - Michele T M Hu
- Nuffield Department of Clinical Neurosciences, Division of Clinical Neurology, University of Oxford, Oxford, UK.,Oxford Parkinson's Disease Centre, University of Oxford, Oxford, UK
| |
Collapse
|
6
|
Clements JD, Perez Ruixo JJ, Gibbs JP, Doshi S, Perez Ruixo C, Melhem M. Receiver Operating Characteristic Analysis and Clinical Trial Simulation to Inform Dose Titration Decisions. CPT-PHARMACOMETRICS & SYSTEMS PHARMACOLOGY 2018; 7:771-779. [PMID: 30246497 PMCID: PMC6263661 DOI: 10.1002/psp4.12354] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 08/23/2018] [Indexed: 11/12/2022]
Abstract
Optimal dose selection in clinical trials is problematic when efficacious and toxic concentrations are close. A novel quantitative approach follows for optimizing dose titration in clinical trials. A system of pharmacokinetics (PK), pharmacodynamics, efficacy, and toxicity was simulated for scenarios characterized by varying degrees of different types of variability. Receiver operating characteristic (ROC) and clinical trial simulation (CTS) were used to optimize drug titration by maximizing efficacy/safety. The scenarios included were a low-variability base scenario, and high residual (20%), interoccasion (20%), interindividual (40%), and residual plus interindividual variability scenarios, and finally a shallow toxicity slope scenario. The percentage of subjects having toxicity was reduced by 87.4% to 93.5%, and those having efficacy was increased by 52.7% to 243%. Interindividual PK variability may have less impact on optimal cutoff values than other sources of variability. ROC/CTS methods for optimizing dose titration offer an individualized approach that leverages exposure-response relationships.
Collapse
Affiliation(s)
- John David Clements
- Clinical Pharmacology and Modeling & Simulation, Amgen Inc., Thousand Oaks, California, USA
| | - Juan Jose Perez Ruixo
- Clinical Pharmacology and Pharmacometrics, Janssen Research and Development, Beerse, Belgium
| | - John P Gibbs
- Clinical Pharmacology and Pharmacometrics, AbbVie, North Chicago, Illinois, USA
| | - Sameer Doshi
- Clinical Pharmacology and Modeling & Simulation, Amgen Inc., Thousand Oaks, California, USA
| | - Carlos Perez Ruixo
- Clinical Pharmacology and Pharmacometrics, Janssen Research and Development, Beerse, Belgium
| | - Murad Melhem
- Clinical Pharmacology, Vertex Pharmaceuticals, Boston, Massachusetts, USA
| |
Collapse
|
7
|
Holden SK, Finseth T, Sillau SH, Berman BD. Progression of MDS-UPDRS Scores Over Five Years in De Novo Parkinson Disease from the Parkinson's Progression Markers Initiative Cohort. Mov Disord Clin Pract 2017; 5:47-53. [PMID: 29662921 DOI: 10.1002/mdc3.12553] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Background The Movement Disorder Society Unified Parkinson Disease Rating Scale (MDS-UDPRS) is a commonly used tool to measure Parkinson disease (PD) progression. Longitudinal changes in MDS-UPDRS scores in de novo PD have not been established. Objective Determine progression rates of MDS-UPDRS scores in de novo PD. Methods 362 participants from the Parkinson's Progression Markers Initiative, a multicenter longitudinal cohort study of de novo PD, were included. Longitudinal progression of MDS-UPDRS total and subscale scores were modeled using mixed model regression. Results MDS-UPDRS scores increased in a linear fashion over five years in de novo PD. MDS-UPDRS total score increased an estimated 4.0 points/year, Part I 0.25 points/year, Part II 1.0 points/year, and Part III 2.4 points/year. Conclusions The expected average progression of MDS-UPDRS scores in de novo PD from this study can assist in clinical monitoring and provide comparative data for detection of disease modification in treatment trials.
Collapse
Affiliation(s)
- Samantha K Holden
- Department of Neurology, University of Colorado Anschutz Medical Campus, Aurora, CO USA
| | - Taylor Finseth
- Department of Neurology, Aurora St. Luke's Medical Center, Milwaukee, WI
| | - Stefan H Sillau
- Department of Neurology, University of Colorado Anschutz Medical Campus, Aurora, CO USA
| | - Brian D Berman
- Department of Neurology, University of Colorado Anschutz Medical Campus, Aurora, CO USA.,Neurology Section, Denver VA Medical Center, Denver, CO USA
| |
Collapse
|
8
|
Musuamba FT, Manolis E, Holford N, Cheung S, Friberg LE, Ogungbenro K, Posch M, Yates J, Berry S, Thomas N, Corriol-Rohou S, Bornkamp B, Bretz F, Hooker AC, Van der Graaf PH, Standing JF, Hay J, Cole S, Gigante V, Karlsson K, Dumortier T, Benda N, Serone F, Das S, Brochot A, Ehmann F, Hemmings R, Rusten IS. Advanced Methods for Dose and Regimen Finding During Drug Development: Summary of the EMA/EFPIA Workshop on Dose Finding (London 4-5 December 2014). CPT-PHARMACOMETRICS & SYSTEMS PHARMACOLOGY 2017; 6:418-429. [PMID: 28722322 PMCID: PMC5529745 DOI: 10.1002/psp4.12196] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 03/27/2017] [Accepted: 03/27/2017] [Indexed: 02/05/2023]
Abstract
Inadequate dose selection for confirmatory trials is currently still one of the most challenging issues in drug development, as illustrated by high rates of late‐stage attritions in clinical development and postmarketing commitments required by regulatory institutions. In an effort to shift the current paradigm in dose and regimen selection and highlight the availability and usefulness of well‐established and regulatory‐acceptable methods, the European Medicines Agency (EMA) in collaboration with the European Federation of Pharmaceutical Industries Association (EFPIA) hosted a multistakeholder workshop on dose finding (London 4–5 December 2014). Some methodologies that could constitute a toolkit for drug developers and regulators were presented. These methods are described in the present report: they include five advanced methods for data analysis (empirical regression models, pharmacometrics models, quantitative systems pharmacology models, MCP‐Mod, and model averaging) and three methods for study design optimization (Fisher information matrix (FIM)‐based methods, clinical trial simulations, and adaptive studies). Pairwise comparisons were also discussed during the workshop; however, mostly for historical reasons. This paper discusses the added value and limitations of these methods as well as challenges for their implementation. Some applications in different therapeutic areas are also summarized, in line with the discussions at the workshop. There was agreement at the workshop on the fact that selection of dose for phase III is an estimation problem and should not be addressed via hypothesis testing. Dose selection for phase III trials should be informed by well‐designed dose‐finding studies; however, the specific choice of method(s) will depend on several aspects and it is not possible to recommend a generalized decision tree. There are many valuable methods available, the methods are not mutually exclusive, and they should be used in conjunction to ensure a scientifically rigorous understanding of the dosing rationale.
Collapse
Affiliation(s)
- F T Musuamba
- EMA Modelling and Simulation Working Group, London, UK.,Federal Agency for Medicines and Health Products, Brussels, Belgium.,UMR850 INSERM, Université de Limoges, Limoges, France
| | - E Manolis
- EMA Modelling and Simulation Working Group, London, UK.,European Medicines Agency, London, UK
| | - N Holford
- Department of Pharmacology & Clinical Pharmacology, University of Auckland, Auckland, New Zealand
| | | | | | | | - M Posch
- Center for Medical Statistics, Informatics and Intelligent Systems, Medical University of Vienna, Vienna, Austria
| | | | - S Berry
- Berry consultants, Austin, Texas, USA
| | | | | | | | - F Bretz
- Center for Medical Statistics, Informatics and Intelligent Systems, Medical University of Vienna, Vienna, Austria.,Novartis, London, UK
| | | | - P H Van der Graaf
- Leiden Academic Centre for Drug Research, Leiden, The Netherlands.,Certara QSP, Canterbury, UK
| | - J F Standing
- EMA Modelling and Simulation Working Group, London, UK.,University College London, London, UK
| | - J Hay
- EMA Modelling and Simulation Working Group, London, UK.,Medicines and Healthcare Products Regulatory Agency, London, UK
| | - S Cole
- EMA Modelling and Simulation Working Group, London, UK.,Medicines and Healthcare Products Regulatory Agency, London, UK
| | - V Gigante
- EMA Modelling and Simulation Working Group, London, UK.,Agenzia Italiana del Farmaco, Roma, Italy
| | - K Karlsson
- EMA Modelling and Simulation Working Group, London, UK.,Medical Products Agency, Uppsala, Sweden
| | | | - N Benda
- EMA Modelling and Simulation Working Group, London, UK.,Bundesinstitut für Arzneimittel und Medizinprodukte, Bonn, Germany
| | - F Serone
- EMA Modelling and Simulation Working Group, London, UK.,Agenzia Italiana del Farmaco, Roma, Italy
| | - S Das
- AstraZeneca UK Limited, London, UK
| | | | - F Ehmann
- European Medicines Agency, London, UK
| | - R Hemmings
- Medicines and Healthcare Products Regulatory Agency, London, UK
| | - I Skottheim Rusten
- EMA Modelling and Simulation Working Group, London, UK.,Norvegian Medicines Agency, Oslo, Norway
| |
Collapse
|
9
|
Paul R, Borah A. L-DOPA-induced hyperhomocysteinemia in Parkinson's disease: Elephant in the room. Biochim Biophys Acta Gen Subj 2016; 1860:1989-97. [DOI: 10.1016/j.bbagen.2016.06.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 05/20/2016] [Accepted: 06/14/2016] [Indexed: 02/08/2023]
|
10
|
Mao ZL, Modi NB. Dose-Response Analysis of the Effect of Carbidopa-Levodopa Extended-Release Capsules (IPX066) in Levodopa-Naive Patients With Parkinson Disease. J Clin Pharmacol 2016; 56:974-82. [PMID: 26632091 PMCID: PMC5066683 DOI: 10.1002/jcph.683] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 11/19/2015] [Indexed: 11/12/2022]
Abstract
Parkinson disease is an age-related disorder of the central nervous system principally due to loss of dopamine-producing cells in the midbrain. Levodopa, in combination with carbidopa, is widely regarded as an effective treatment for the symptoms of Parkinson disease. A dose-response relationship is established for carbidopa-levodopa extended-release capsules (IPX066) in levodopa-naive Parkinson disease patients using a disease progression model. Unified Parkinson Disease Rating Scale (UPDRS) part II plus part III scores from 171 North American patients treated with placebo or IPX066 for approximately 30 weeks from a double-blind, parallel-group, dose-ranging study were used to develop the pharmacodynamic model. The model comprised 3 components: a linear function describing disease progression, a component describing placebo (or nonlevodopa) effects, and a component to describe the effect of levodopa. Natural disease progression in early Parkinson disease as measured by UPDRS was 11.6 units/year and faster in patients with more severe disease (Hoehn-Yahr stage 3). Maximum placebo/nonlevodopa response was 23.0% of baseline UPDRS. Maximum levodopa effect from IPX066 was 76.7% of baseline UPDRS, and the ED50 was 450 mg levodopa. Equilibration half-life for the effect compartment was 62.8 days. Increasing age increased and being female decreased equilibration half-life. The quantitative model allowed description of the entire time course of response to clinical trial intervention.
Collapse
Affiliation(s)
| | - Nishit B. Modi
- Impax Specialty Pharmaa division of Impax LaboratoriesIncHaywardCAUSA
| |
Collapse
|
11
|
Venuto CS, Potter NB, Dorsey ER, Kieburtz K. A review of disease progression models of Parkinson's disease and applications in clinical trials. Mov Disord 2016; 31:947-956. [PMID: 27226141 PMCID: PMC4931998 DOI: 10.1002/mds.26644] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Revised: 02/19/2016] [Accepted: 03/04/2016] [Indexed: 12/31/2022] Open
Abstract
Quantitative disease progression models for neurodegenerative disorders are gaining recognition as important tools for drug development and evaluation. In Parkinson's disease (PD), several models have described longitudinal changes in the Unified Parkinson's Disease Rating Scale (UPDRS), one of the most utilized outcome measures for PD trials assessing disease progression. We conducted a literature review to examine the methods and applications of quantitative disease progression modeling for PD using a combination of key words including "Parkinson disease," "progression," and "model." For this review, we focused on models of PD progression quantifying changes in the total UPDRS scores against time. Four different models reporting equations and parameters have been published using linear and nonlinear functions. The reasons for constructing disease progression models of PD thus far have been to quantify disease trajectories of PD patients in active and inactive treatment arms of clinical trials, to quantify and discern symptomatic and disease-modifying treatment effects, and to demonstrate how model-based methods may be used to design clinical trials. The historical lack of efficiency of PD clinical trials begs for model-based simulations in planning for studies that result in more informative conclusions, particularly around disease modification. © 2016 International Parkinson and Movement Disorder Society.
Collapse
Affiliation(s)
- Charles S. Venuto
- Center for Human Experimental Therapeutics, University of Rochester, Rochester, NY, USA
- Department of Neurology, University of Rochester, Rochester NY USA
| | - Nicholas B. Potter
- Center for Human Experimental Therapeutics, University of Rochester, Rochester, NY, USA
| | - E. Ray Dorsey
- Center for Human Experimental Therapeutics, University of Rochester, Rochester, NY, USA
- Department of Neurology, University of Rochester, Rochester NY USA
| | - Karl Kieburtz
- Center for Human Experimental Therapeutics, University of Rochester, Rochester, NY, USA
- Department of Neurology, University of Rochester, Rochester NY USA
| |
Collapse
|
12
|
Liu Y, Fan JH, Gao X, Ma L, Qiao YL, Zhang L. The Natural Progression of Parkinson's Disease in a Small Cohort with 15 Drug-naïve Patients. Chin Med J (Engl) 2015; 128:1761-4. [PMID: 26112717 PMCID: PMC4733712 DOI: 10.4103/0366-6999.159350] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2015] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND The studies of the natural progression of Parkinson's disease (PD) in Chinese populations have been lacking. To address this issue and obtain a preliminary data, we conducted a PD progression assessment in 15 adults with de novo PD from a nutritional intervention trial (NIT) cohort in Lin County China. METHODS Using the Copiah County screening questionnaire and United Kingdom Parkinson's Disease Society Brain Bank diagnostic criteria, we surveyed the available NIT cohort members in 2000 and diagnosed 86 patients as PD. In 2010, we resurveyed all PD patients and confirmed definite PD diagnosis in 15 cases with the rest of them being dead (54); having probable (10) PD or vascular Parkinsonism (3); refusing to participate (2); or being away (2). In both surveys, we used Hoehn and Yahr (HY) scale and assessed the disease progression. Unified Parkinson's Disease Rating Scale (UPDRS) was added to the second survey. RESULTS In 2010, the average disease duration for 15 definite PD patients was 13.6 ± 7.3 years. Over a 10-year time span, 9 out of 15 patients remained at the same HY stage while the remaining 6 progressed. Rigidity (47% vs. 100%; P = 0.002) and postural instability (7% vs. 47%; P = 0.005) worsened significantly. The mean UPDRS motor scores in 2010 were 39.4 ± 23.7. CONCLUSIONS Overall worsening of motor function in PD seems to be the rule in this untreated cohort, and their rate of progression seemed to be slower than those reported in the western populations.
Collapse
Affiliation(s)
- Ying Liu
- Department of Neurology, Dalian Municipal Friendship Hospital, Dalian, Liaoning 116001, China
| | - Jin-Hu Fan
- Department of Cancer Epidemiology, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Xiang Gao
- Department of Medicine, Channing Laboratory, Brigham and Women's Hospital, and Harvard Medical School, Boston, MA 02115, USA
- Department of Nutrition, Harvard University School of Public Health, Boston, MA 02115, USA
| | - Li Ma
- Department of Epidemiology, Dalian Medical University, Dalian, Liaoning 116044, China
| | - You-Lin Qiao
- Department of Cancer Epidemiology, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
| | - Lin Zhang
- Department of Neurology, University of California Davis School of Medicine, Sacramento, CA 95817, USA
| |
Collapse
|
13
|
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease and pathologically is characterised by a progressive loss of dopaminergic cells of the nigrostriatal pathway. Clinically, PD is mainly defined by the presence of the motor symptoms of bradykinesia, rigidity, rest tremor and postural instability, but non-motor symptoms such as depression, dementia and autonomic disturbances are recognised as integral parts of the disease. Although pharmacotherapy for PD was introduced almost 50 years ago, and has improved significantly over the intervening period, the timing of initiation of treatment in newly diagnosed PD remains controversial. While some physicians favour an early start of pharmacotherapy at or soon after diagnosis, others prefer to delay pharmacological treatment until a certain degree of disability has developed. This article aims to discuss the advantages and disadvantages of both strategies by exploring their effects on symptoms, disease progression and quality of life. Although the data on putative disease-modifying effects of early pharmacological intervention in PD are still inconclusive, we believe that the most important indication for an early initiation of anti-parkinsonian treatment should be to maintain the quality of life of PD patients and to secure their socioeconomic status as long as possible.
Collapse
|
14
|
Disease progression and neuroscience. J Pharmacokinet Pharmacodyn 2013; 40:369-76. [DOI: 10.1007/s10928-013-9316-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Accepted: 04/09/2013] [Indexed: 10/26/2022]
|
15
|
Trial Treatment Length Optimization With an Emphasis on Disease Progression Studies. J Clin Pharmacol 2013; 49:323-35. [DOI: 10.1177/0091270008329560] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
16
|
Marshall SF, Hemmings R, Josephson F, Karlsson MO, Posch M, Steimer JL. Modeling and simulation to optimize the design and analysis of confirmatory trials, characterize risk-benefit, and support label claims. CPT Pharmacometrics Syst Pharmacol 2013; 2:e27. [PMID: 23835938 PMCID: PMC3600757 DOI: 10.1038/psp.2013.4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 01/14/2013] [Indexed: 11/16/2022] Open
Abstract
The role of modeling and simulation (M&S) in the design and interpretation of phase III studies, from break out session 4 of the European Medicines Agency (EMA)/European Federation of Pharmaceutical Industries and Associations (EFPIA) M&S workshop, was divided into themes illustrated with case studies (Table 1): (1) M&S being conducted to support the design of confirmatory trials; (2) longitudinal model‐based test as primary inferential analysis (biosimilarity and disease progression trials); (3) assessment of benefit–risk ratio, approval and labeling of an unstudied dose or dosing regimen, and development of future regulatory guidance.CPT: Pharmacometrics & Systems Pharmacology (2013) 2, e27; doi:10.1038/psp.2013.4; advance online publication 27 February 2013
Collapse
Affiliation(s)
- S F Marshall
- Pfizer, Pharmacometrics, Global Clinical, Pharmacology, Sandwich, UK
| | - R Hemmings
- European Medicines Agency (EMA), London, UK
- Medicines and Healthcare Products Regulatory Agency (MHRA), London, UK
| | - F Josephson
- European Medicines Agency (EMA), London, UK
- Swedish Medical Products Agency (MPA), Uppsala, Sweden
| | - M O Karlsson
- Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | - M Posch
- European Medicines Agency (EMA), London, UK
- Current address: Section of Medical Statistics, CEMSIIS Medical University of Vienna, Vienna, Austria
| | - J-L Steimer
- Novartis, Modeling & Simulation, Pharma Development, Basel, Switzerland
| |
Collapse
|
17
|
Vu TC, Nutt JG, Holford NHG. Progression of motor and nonmotor features of Parkinson's disease and their response to treatment. Br J Clin Pharmacol 2012; 74:267-83. [PMID: 22283961 DOI: 10.1111/j.1365-2125.2012.04192.x] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
AIMS (i) To describe the progression of the cardinal features of Parkinson's disease (PD); (ii) to investigate whether baseline PD subtypes explain disease progression; and (iii) to quantify the symptomatic and disease-modifying effects of anti-parkinsonian treatments. METHODS Data were available for 795 PD subjects, initially untreated, followed for up to 8 years. Cardinal features [tremor, rigidity, bradykinesia, and postural instability and gait disorder (PIGD)] were derived from the total unified Parkinson's disease rating scale (total UPDRS), cognitive status from the mini-mental status exam score (MMSE) and depression status from the Hamilton depression scale (HAM-D). Analysis was performed using a nonlinear mixed effects approach with an asymptotic model for natural disease progression. Treatment effects (i.e. symptomatic and disease modifying) were evaluated by describing changes in the natural history model parameters. RESULTS Tremor progressed more slowly (half-time of 3.9 years) than all other motor features (half-time 2-3 years). The MMSE progression was negligible, while HAM-D progressed with a half-time of 5 years. Levodopa had marked symptomatic effects on all features, but low potency for effect on PIGD (ED₅₀ of 1237 mg day⁻¹ compared with 7-24 mg day⁻¹ for other motor and nonmotor features). Other anti-parkinsonian treatments had much smaller symptomatic effects. All treatments had disease-modifying effects on the cardinal features of PD. Baseline PD subtypes only explained small differences in disease progression. CONCLUSIONS This analysis indicates that tremor progresses more slowly than other cardinal features and that PIGD is less treatment responsive in early PD patients. There was no evidence of baseline PD subtypes as a clinically useful predictor of disease progression rate. Anti-parkinsonian treatments have symptomatic and disease-modifying effects on all major features of PD.
Collapse
Affiliation(s)
- Thuy C Vu
- Department of Pharmacokinetics and Drug Metabolism, Amgen Inc., Thousand Oaks, CA, USA
| | | | | |
Collapse
|
18
|
Boll MC, Alcaraz-Zubeldia M, Rios C. Medical management of Parkinson's disease: focus on neuroprotection. Curr Neuropharmacol 2012; 9:350-9. [PMID: 22131943 PMCID: PMC3131725 DOI: 10.2174/157015911795596577] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Revised: 07/21/2010] [Accepted: 08/13/2010] [Indexed: 12/12/2022] Open
Abstract
Neuroprotection refers to the protection of neurons from excitotoxicity, oxidative stress and apoptosis as principal mechanisms of cell loss in a variety of diseases of the central nervous system. Our interest in Parkinson’s disease (PD) treatment is focused on drugs with neuroprotective properties in preclinical experiments and evidence-based efficacy in human subjects. To this date, neuroprotection has never been solidly proven in clinical trials but recent adequate markers and/or strategies to study and promote this important goal are described. A myriad of compounds with protective properties in cell cultures and animal models yield to few treatments in clinical practice. At present, markers of neuronal vitality, disease modifying effects and long term clinical stability are the elements searched for in clinical trials. This review highlights new strategies to monitor patients with PD. Currently, neuroprotection in subjects has not been solidly achieved for selegiline and pramipexole; however, a recent rasagiline trial design is showing new indications of disease course modifying effects. In neurological practice, it is of utmost importance to take into account the potential neuroprotection exerted by a treatment in conjunction with its symptomatic efficacy.
Collapse
Affiliation(s)
- Marie-Catherine Boll
- Department of Clinical Investigation in Neurology National Institute of Neurology and Neurosurgery, Mexico. D.F
| | | | | |
Collapse
|
19
|
|
20
|
Malek NM, Grosset DG. Enhancing dopamine treatments: worth the effort? Neurodegener Dis Manag 2012. [DOI: 10.2217/nmt.12.36] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
SUMMARY Dopamine-based treatments underlie our current management of the motor symptoms of Parkinson’s disease. In this article, we look at the development of levodopa therapy, combination therapies with levodopa/dopa decarboxylase inhibitors, use of dopamine agonists, monoamine oxidase inhibitors, catechol-O-methyl transferase inhibitors and the development of nonoral delivery methods, in particular in the treatment of motor complications in later PD. There are some shortcomings of dopamine-based therapies including a limited benefit on the non-motor manifestations of Parkinson’s disease. We conclude by looking at the themes for future developments to further enhance dopamine delivery methods.
Collapse
Affiliation(s)
- Naveed M Malek
- Institute of Neurological Sciences, Southern General Hospital, Glasgow, G51 4TF, UK
| | - Donald G Grosset
- Institute of Neurological Sciences, Southern General Hospital, Glasgow, G51 4TF, UK
| |
Collapse
|
21
|
Xia Y, Jiang C, Cao Z, Shi K, Wang Y. Co-transplantation of macaque autologous Schwann cells and human embryonic nerve stem cells in treatment of macaque Parkinson's disease. ASIAN PAC J TROP MED 2012; 5:7-14. [PMID: 22182636 DOI: 10.1016/s1995-7645(11)60237-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Revised: 11/15/2011] [Accepted: 12/15/2011] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVE To investigate the therapeutic effects of co-transplantation with Schwann cells (SCs) and human embryonic nerve stem cells (NSCs) on macaque Parkinson's disease (PD). METHODS Macaque autologous SCs and human embryonic NSCs were adopted for the treatment of macaque PD. RESULTS Six months after transplantation, positron emission computerized tomography showed that (18)F-FP-β-CIT was significantly concentrated in the injured striatum in the co-transplanted group. Immunohistochemical staining of transplanted area tissue showed migration of tyroxine hydroxylase positive cells from the transplant area to the surrounding area was significantly increased in the co-transplanted group. CONCLUSIONS Co-transplantation of SCs and NSCs could effectively cure PD in macaques. SCs harvested from the autologous peripheral nerves can avoid rejection and the ethics problems, so it is expected to be applied clinically.
Collapse
Affiliation(s)
- Ying Xia
- Department of Neurosurgery, Haikou Hospital, Xiangya Medical School, Central South University, Haikou, China.
| | | | | | | | | |
Collapse
|
22
|
Ljungdahl A, Hanrieder J, Fälth M, Bergquist J, Andersson M. Imaging mass spectrometry reveals elevated nigral levels of dynorphin neuropeptides in L-DOPA-induced dyskinesia in rat model of Parkinson's disease. PLoS One 2011; 6:e25653. [PMID: 21984936 PMCID: PMC3184165 DOI: 10.1371/journal.pone.0025653] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 09/08/2011] [Indexed: 11/18/2022] Open
Abstract
L-DOPA-induced dyskinesia is a troublesome complication of L-DOPA pharmacotherapy of Parkinson's disease and has been associated with disturbed brain opioid transmission. However, so far the results of clinical and preclinical studies on the effects of opioids agonists and antagonists have been contradictory at best. Prodynorphin mRNA levels correlate well with the severity of dyskinesia in animal models of Parkinson's disease; however the identities of the actual neuroactive opioid effectors in their target basal ganglia output structures have not yet been determined. For the first time MALDI-TOF imaging mass spectrometry (IMS) was used for unbiased assessment and topographical elucidation of prodynorphin-derived peptides in the substantia nigra of a unilateral rat model of Parkinson's disease and L-DOPA induced dyskinesia. Nigral levels of dynorphin B and alpha-neoendorphin strongly correlated with the severity of dyskinesia. Even if dynorphin peptide levels were elevated in both the medial and lateral part of the substantia nigra, MALDI IMS analysis revealed that the most prominent changes were localized to the lateral part of the substantia nigra. MALDI IMS is advantageous compared with traditional molecular methods, such as radioimmunoassay, in that neither the molecular identity analyzed, nor the specific localization needs to be predetermined. Indeed, MALDI IMS revealed that the bioconverted metabolite leu-enkephalin-arg also correlated positively with severity of dyskinesia. Multiplexing DynB and leu-enkephalin-arg ion images revealed small (0.25 by 0.5 mm) nigral subregions with complementing ion intensities, indicating localized peptide release followed by bioconversion. The nigral dynorphins associated with L-DOPA-induced dyskinesia were not those with high affinity to kappa opioid receptors, but consisted of shorter peptides, mainly dynorphin B and alpha-neoendorphin that are known to bind and activate mu and delta opioid receptors. This suggests that mu and/or delta subtype-selective opioid receptor antagonists may be clinically relevant for reducing L-DOPA-induced dyskinesia in Parkinson's disease.
Collapse
Affiliation(s)
- Anna Ljungdahl
- Department of Pharmaceutical Biosciences, Drug Safety and Toxicology, Uppsala University, Uppsala, Sweden
| | | | | | | | | |
Collapse
|
23
|
Chen C, Cowles VE, Sweeney M, Stolyarov ID, Illarioshkin SN. Pharmacokinetics of levodopa/carbidopa delivered from gastric-retentive extended-release formulations in patients with Parkinson's disease. J Clin Pharmacol 2011; 52:1069-77. [PMID: 21610205 DOI: 10.1177/0091270011409232] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The investigators conducted a single-dose pharmacokinetic (PK) study of levodopa/carbidopa delivered from novel gastric-retentive extended-release (ER) tablets versus a comparator ER tablet (M-ER) in patients with Parkinson's disease. Two levodopa/carbidopa (200 mg/50 mg) gastric-retentive ER formulations (4 hours and 6 hours) and M-ER were administered orally with food. Blood samples were collected for up to 24 hours post dose to determine levodopa and carbidopa concentrations. Tolerability was assessed by monitoring adverse events and measuring vital signs. PK modeling was conducted to estimate the release characteristics for future gastric-retentive ER formulations to achieve a less fluctuating plasma concentration profiles. Compared with M-ER, both gastric-retentive ER formulations exhibited a longer time to reach a lower maximal plasma concentration for levodopa and carbidopa. The 4-hour formulation demonstrated a similar area under the concentration-time curve compared with M-ER, whereas the 6-hour formulation demonstrated a lower area under the concentration-time curve. All formulations were well tolerated. Modeling suggests that a gastric-retentive ER formulation with a longer release duration administered twice daily may achieve a less fluctuating levodopa concentration profile than M-ER administered 3 times daily. This study demonstrates that gastric-retentive ER dosage forms may reduce dose frequency while minimizing the plasma peak-to-trough fluctuation and consequently reduce motor fluctuation in patients with Parkinson's disease.
Collapse
|
24
|
Clarke CE, Patel S, Ives N, Rick C, Wheatley K, Gray R. Should treatment for Parkinson's disease start immediately on diagnosis or delayed until functional disability develops? Mov Disord 2011; 26:1187-93. [DOI: 10.1002/mds.23519] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Revised: 08/20/2010] [Accepted: 10/13/2010] [Indexed: 12/14/2022] Open
|
25
|
Holford NHG, Nutt JG. Interpreting the results of Parkinson's disease clinical trials: Time for a change. Mov Disord 2011; 26:569-77. [DOI: 10.1002/mds.23555] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2010] [Revised: 10/12/2010] [Accepted: 11/01/2010] [Indexed: 11/11/2022] Open
|
26
|
Smith MK, Marshall A. Importance of protocols for simulation studies in clinical drug development. Stat Methods Med Res 2010; 20:613-22. [PMID: 20688782 DOI: 10.1177/0962280210378949] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Clinical trial simulation studies can be used to assess the impact of many aspects of trial design, conduct, analysis and decision making on trial performance metrics. Simulation studies can play a vital role in improving the efficiency of the drug development process within the pharmaceutical industry, but only if they are well designed and conducted. It is imperative therefore that a protocol or simulation plan is developed, documenting how the simulation study is to be conducted, analysed and reported. This article emphasises the specific considerations necessary for designing good quality simulation studies. These include defining data generation processes, data analytic methods, decision criteria and also determining the presentation of results for all intended audiences. With clinical trial simulations becoming a vital part of the drug development process, the protocol for clinical trial simulations may in future become part of the regulatory peer review process. More rigour in the planning and execution of simulation studies will ensure that the design, analysis and decision-making process for the subsequent clinical trial is based on credible evidence that can be independently verified.
Collapse
|
27
|
|
28
|
George JL, Mok S, Moses D, Wilkins S, Bush AI, Cherny RA, Finkelstein DI. Targeting the progression of Parkinson's disease. Curr Neuropharmacol 2010; 7:9-36. [PMID: 19721815 PMCID: PMC2724666 DOI: 10.2174/157015909787602814] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2008] [Revised: 08/15/2008] [Accepted: 09/09/2008] [Indexed: 02/07/2023] Open
Abstract
By the time a patient first presents with symptoms of Parkinson's disease at the clinic, a significant proportion (50-70%) of the cells in the substantia nigra (SN) has already been destroyed. This degeneration progresses until, within a few years, most of the cells have died. Except for rare cases of familial PD, the initial trigger for cell loss is unknown. However, we do have some clues as to why the damage, once initiated, progresses unabated. It would represent a major advance in therapy to arrest cell loss at the stage when the patient first presents at the clinic. Current therapies for Parkinson's disease focus on relieving the motor symptoms of the disease, these unfortunately lose their effectiveness as the neurodegeneration and symptoms progress. Many experimental approaches are currently being investigated attempting to alter the progression of the disease. These range from replacement of the lost neurons to neuroprotective therapies; each of these will be briefly discussed in this review. The main thrust of this review is to explore the interactions between dopamine, alpha synuclein and redox-active metals. There is abundant evidence suggesting that destruction of SN cells occurs as a result of a self-propagating series of reactions involving dopamine, alpha synuclein and redox-active metals. A potent reducing agent, the neurotransmitter dopamine has a central role in this scheme, acting through redox metallo-chemistry to catalyze the formation of toxic oligomers of alpha-synuclein and neurotoxic metabolites including 6-hydroxydopamine. It has been hypothesized that these feed the cycle of neurodegeneration by generating further oxidative stress. The goal of dissecting and understanding the observed pathological changes is to identify therapeutic targets to mitigate the progression of this debilitating disease.
Collapse
Affiliation(s)
- J L George
- The Mental Health Research Institute of Victoria , 155 Oak Street, Parkville, Victoria 3052, Australia
| | | | | | | | | | | | | |
Collapse
|
29
|
Fernandez N, Garcia JJ, Diez MJ, Sahagun AM, Díez R, Sierra M. Effects of dietary factors on levodopa pharmacokinetics. Expert Opin Drug Metab Toxicol 2010; 6:633-42. [DOI: 10.1517/17425251003674364] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
|
30
|
|
31
|
Wang SJ. Commentary on “Experiences in Model/Simulation for Early Phase or Late Phase Study Planning Aimed to Learn Key Design Elements”. Stat Biopharm Res 2009. [DOI: 10.1198/sbr.2009.0066] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
32
|
Marin C, Aguilar E, Mengod G, Cortés R, Obeso JA. Effects of early vs. late initiation of levodopa treatment in hemiparkinsonian rats. Eur J Neurosci 2009; 30:823-32. [DOI: 10.1111/j.1460-9568.2009.06877.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
33
|
Mosharov EV, Sulzer D. Convergence of multiple hits that could underlie Parkinson’s disease. FUTURE NEUROLOGY 2009. [DOI: 10.2217/fnl.09.40] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
| | - David Sulzer
- Department of Neurology, Columbia University, NY, USA
| |
Collapse
|
34
|
Koh SH, Kim SH, Kim HT. Role of glycogen synthase kinase-3 inl-DOPA-induced neurotoxicity. Expert Opin Drug Metab Toxicol 2009; 5:1359-68. [DOI: 10.1517/17425250903170663] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
|
35
|
Abstract
Levodopa serves as the gold standard of anti-parkinsonian therapy and nearly every patient with Parkinson's disease eventually receives this drug. To improve upon levodopa therapy, several forms of treatment have been devised to augment its actions, and new delivery systems are under development. This new research offers promise for improving outcomes with this highly effective therapy.
Collapse
Affiliation(s)
- Peter A LeWitt
- Department of Neurology, Henry Ford Hospital, and the Department of Neurology, Wayne State University School of Medicine, Detroit, Michigan 48034, USA.
| |
Collapse
|
36
|
Abstract
Dopamine (DA) supplementation therapy by l-dopa for Parkinson's disease (PD) was established around 1970. The dose of l-dopa can be reduced by the combined administration of inhibitors of peripheral l-amino acid decarboxylase (AADC), catechol O-methyltransferase (COMT), or monoamine oxidase B (MAO B). DA in the striatum may be produced from exogenously administered l-dopa by various AADC-containing cells, such as serotonin neurons. The long-term administration of l-dopa in PD patients may produce l-dopa-induced dyskinesia (LID), which may be due to chronic overstimulation of supersensitive DA D1 receptors. l-dopa may be used in combination with various new strategies such as gene therapy or transplantation in the future.
Collapse
Affiliation(s)
- Toshiharu Nagatsua
- Department of Pharmacology, School of Medicine, Fujita Health University, Toyoake, Aichi 470-1192, Japan.
| | | |
Collapse
|
37
|
Chen CM, Liu JL, Wu YR, Chen YC, Cheng HS, Cheng ML, Chiu DTY. Increased oxidative damage in peripheral blood correlates with severity of Parkinson's disease. Neurobiol Dis 2008; 33:429-35. [PMID: 19110057 DOI: 10.1016/j.nbd.2008.11.011] [Citation(s) in RCA: 255] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Revised: 11/08/2008] [Accepted: 11/25/2008] [Indexed: 10/21/2022] Open
Abstract
Increased oxidative stress contributes to neuronal dysfunction in Parkinson's disease (PD). We investigated whether the pathological changes in PD brains may also be present in peripheral tissues. Leukocyte 8-hydroxydeoxyguanosine (8-OHdG), plasma malondialdehyde (MDA), erythrocyte glutathione peroxidase (GPx) and plasma vitamin E (Vit E) were measured for 211 PD patients and 135 healthy controls. Leukocyte 8-OHdG and plasma MDA were elevated, whereas erythrocyte GPx and plasma Vit E were reduced in PD patients when compared to the controls. After adjusting for environmental factors, logistic regression analysis showed that PD severity was independently correlated with 8-OHdG and MDA level, and inversely correlated with GPx activity and Vit E level. Leucocyte 8-OHdG level was continuously increased with advanced PD Hoehn-Yahr stages, while plasma MDA level peaked at early disease stages, among PD patients. These results suggest increased oxidative damage and decreased anti-oxidant capacity in peripheral blood, and a significant correlation between leucocyte 8-OHdG level and disease severity in PD.
Collapse
Affiliation(s)
- Chiung-Mei Chen
- Department of Neurology, Chang Gung Memorial Hospital, Chang-Gung University College of Medicine, Taipei, Taiwan.
| | | | | | | | | | | | | |
Collapse
|
38
|
Affiliation(s)
- Peter A Lewitt
- Department of Neurology, Henry Ford Hospital, and the Department of Neurology, Wayne State University School of Medicine, Detroit, USA.
| |
Collapse
|
39
|
Ploeger BA, Holford NHG. Washout and delayed start designs for identifying disease modifying effects in slowly progressive diseases using disease progression analysis. Pharm Stat 2008; 8:225-38. [DOI: 10.1002/pst.355] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
40
|
Abstract
Treatments with potential neuroprotective capability for Parkinson's disease (PD) have been investigated in randomized, controlled, clinical trials and other studies since the mid-1980s. Although promising leads have arisen, no therapy has been proven to halt or slow disease progression. Several large-scale studies have highlighted progress in methodology, as well as the frustrations of translating laboratory science to practical applications. This review summarizes findings from clinical trials with several classes of compounds, including monoamine oxidase-B inhibitors (selegiline, lazabemide, rasagiline), dopaminergic drugs (ropinirole, pramipexole, levodopa), antioxidant strategies (alpha-tocopherol), mitochondrial energy enhancers (coenzyme Q(10), creatine), antiapoptotic agents (TCH346, minocycline, CEP-1347), and antiglutamatergic compounds (riluzole). Beyond small-molecule pharmacology, gene therapy approaches, such as delivering neurotrophic substances (e.g., neurturin) by viral vector, are the next generation of treatment options.
Collapse
Affiliation(s)
- Peter A LeWitt
- Department of Neurology, Henry Ford Hospital, Detroit, Michigan, USA.
| | | |
Collapse
|
41
|
|
42
|
Holford N, Nutt JG. Disease progression, drug action and Parkinson's disease: why time cannot be ignored. Eur J Clin Pharmacol 2007; 64:207-16. [PMID: 18092155 DOI: 10.1007/s00228-007-0427-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2007] [Accepted: 11/22/2007] [Indexed: 12/21/2022]
Affiliation(s)
- Nick Holford
- Department of Pharmacology and Clinical Pharmacology, University of Auckland, Auckland, New Zealand.
| | | |
Collapse
|