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Polgar S, Finkelstein DI, Karimi L. Overcoming Methodological Challenges for Advancing Stem Cell Therapies in Parkinson's Disease. Cell Transplant 2024; 33:9636897241246355. [PMID: 38634440 PMCID: PMC11027592 DOI: 10.1177/09636897241246355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 03/19/2024] [Accepted: 03/20/2024] [Indexed: 04/19/2024] Open
Abstract
The quest for new and improved therapies for Parkinson's disease (PD) remains of paramount importance, despite previous trial failures. There is a current debate regarding the potential of stem cell research as a therapeutic approach for PD. The studies of dopaminergic fetal stem cells for PD treatment, their design, and the results of the initial surgical placebo-controlled trials were reviewed in this study. Some of the fundamental methodological challenges and possible strategies to resolve them were proposed. In this article, we argue that the most important impact lies in the proof-of-principle demonstrated by clinical trials for cell replacement strategies in reconstructing the human brain. While some researchers argue that the considerable technical challenges associated with cell therapies for PD warrant the discontinuation of further development using stem cells, we believe that the opposing viewpoints are instrumental in identifying a series of methodological misunderstandings. Here, we propose to expose key challenges to ensure the advancement of the field and unlock the potential of stem cell therapies in PD treatment. Overall, this review underscores the need for further research and innovation to overcome the hurdles in realizing the potential of stem cell-based therapies for PD.
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Affiliation(s)
- Stephen Polgar
- School of Health and Biomedical Sciences, RMIT University, Melbourne, VIC, Australia
| | - David I. Finkelstein
- University of Melbourne, Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia
| | - Leila Karimi
- School of Health and Biomedical Sciences, RMIT University, Melbourne, VIC, Australia
- School of Medicine and Healthcare Management, Caucasus University, Tbilisi, Georgia
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2
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Quintero JE, Slevin JT, Gurwell JA, McLouth CJ, El Khouli R, Chau MJ, Guduru Z, Gerhardt GA, van Horne CG. Direct delivery of an investigational cell therapy in patients with Parkinson's disease: an interim analysis of feasibility and safety of an open-label study using DBS-Plus clinical trial design. BMJ Neurol Open 2022; 4:e000301. [PMID: 35949912 PMCID: PMC9295654 DOI: 10.1136/bmjno-2022-000301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 06/13/2022] [Indexed: 12/29/2022] Open
Abstract
Objective To evaluate the interim feasibility, safety and clinical measures data of direct delivery of regenerating peripheral nerve tissue (PNT) to the substantia nigra (SN) in participants with Parkinson’s disease (PD). Methods Eighteen (13 men/5 women) participants were unilaterally implanted with PNT to the SN, contralateral to the most affected side during the same surgery they were receiving deep brain stimulation (DBS) surgery. Autologous PNT was collected from the sural nerve. Participants were followed for safety and clinical outcomes for 2 years (including off-state Unified Parkinson’s Disease Rating Scale (UPDRS) Part III assessments) with study visits every 6 months. Results All 18 participants scheduled to receive PNT implantation received targeted delivery to the SN in addition to their DBS. All subjects were discharged the following day except for two: post-op day 2; post-op day 3. The most common study-related adverse events were hypoaesthesia and hyperaesthesias to the lateral aspect of the foot and ankle of the biopsied nerve (6 of 18 participants experienced). Clinical measures did not identify any hastening of PD measures providing evidence of safety and tolerability. Off-state UPDRS Part III mean difference scores were reduced at 12 months compared with baseline (difference=−8.1, 95% CI −2.4 to −13.9 points, p=0.005). No complications involving dyskinesias were observed. Conclusions Targeting the SN for direct delivery of PNT was feasible with no serious adverse events related to the study intervention. Interim clinical outcomes show promising results meriting continued examination of this investigational approach. Trial registration number NCT02369003.
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Affiliation(s)
- Jorge E Quintero
- Neurosurgery, University of Kentucky Medical Center, Lexington, Kentucky, USA.,Neuroscience, University of Kentucky Medical Center, Lexington, Kentucky, USA
| | - John T Slevin
- Neurology, University of Kentucky Medical Center, Lexington, Kentucky, USA.,Neurology, VA Medical Center, Lexington, Kentucky, USA
| | - Julie A Gurwell
- Neurology, University of Kentucky Medical Center, Lexington, Kentucky, USA
| | | | - Riham El Khouli
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, University of Kentucky Medical Center, Lexington, Kentucky, USA
| | - Monica J Chau
- Neurosurgery, University of Kentucky Medical Center, Lexington, Kentucky, USA
| | - Zain Guduru
- Neurology, University of Kentucky Medical Center, Lexington, Kentucky, USA
| | - Greg A Gerhardt
- Neurosurgery, University of Kentucky Medical Center, Lexington, Kentucky, USA.,Neuroscience, University of Kentucky Medical Center, Lexington, Kentucky, USA.,Neurology, University of Kentucky Medical Center, Lexington, Kentucky, USA
| | - Craig G van Horne
- Neurosurgery, University of Kentucky Medical Center, Lexington, Kentucky, USA.,Neuroscience, University of Kentucky Medical Center, Lexington, Kentucky, USA
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3
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Nam JY, Lee TY, Kim K, Chun S, Kim MS, Shin JH, Sung JJ, Kim BJ, Kim BJ, Oh KW, Kim KS, Kim SH. Efficacy and safety of Lenzumestrocel (Neuronata-R® inj.) in patients with amyotrophic lateral sclerosis (ALSUMMIT study): study protocol for a multicentre, randomized, double-blind, parallel-group, sham procedure-controlled, phase III trial. Trials 2022; 23:415. [PMID: 35585556 PMCID: PMC9115933 DOI: 10.1186/s13063-022-06327-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Accepted: 04/23/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A single cycle (two repeated treatments) with intrathecal autologous bone marrow-derived mesenchymal stem cells (BM-MSCs, 26-day interval) showed safety and provided therapeutic benefit lasting 6 months in patients with ALS but did not demonstrate long-term efficacy. This phase III clinical trial (ALSUMMIT) protocol was developed to evaluate the long-term efficacy and safety of the combined protocol of single-cycle intrathecal therapy and three additional booster injections of BM-MSC (Lenzumestrocel) treatment in patients with ALS. METHODS ALSUMMIT is a multicentre, randomized, double-blind, parallel-group, sham procedure-controlled, phase III trial for ALS. The 115 subjects will be randomized (1:2:2) into three groups: (1) study Group 1 (single-cycle, two repeated injections with 26-day interval), (2) study Group 2 (single-cycle + three additional booster injections at 4, 7, and 10 months), and (3) the control group. Participants who have an intermediate rate of disease progression will be included in this trial to reduce clinical heterogeneity. The primary endpoint will be evaluated by combined assessment of function and survival (CAFS), also known as joint rank scores (JRS), at 6 months (study Group 1 vs. control) and 12 months (study Group 2 vs. control) after the first Lenzumestrocel or placebo administration. Safety assessment will be performed throughout the study period. Additionally, after the 56-week main study, a long-term follow-up observational study will be conducted to evaluate the long-term efficacy and safety up to 36 months. DISCUSSION Lenzumestrocel is the orphan cell therapy product for ALS conditionally approved by the South Korea Ministry of Food and Drug Safety (MFDS). This ALSUMMIT protocol was developed for the adoption of enrichment enrolment, add-on design, and consideration of ethical issues for the placebo group. TRIAL REGISTRATION ClinicalTrials.gov NCT04745299 . Registered on Feb 9, 2021. Clinical Research Information Service (CRIS) KCT0005954 . Registered on Mar 4, 2021.
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Affiliation(s)
- Jae-Yong Nam
- Central Research Center, Corestem Inc, Seoul, South Korea
| | - Tae Yong Lee
- Central Research Center, Corestem Inc, Seoul, South Korea.,College of Pharmacy, Chungbuk National University, Cheongju, South Korea
| | - Kwijoo Kim
- Central Research Center, Corestem Inc, Seoul, South Korea
| | - Sehwan Chun
- Central Research Center, Corestem Inc, Seoul, South Korea
| | - Min Sung Kim
- Central Research Center, Corestem Inc, Seoul, South Korea.,College of Pharmacy, Chungbuk National University, Cheongju, South Korea
| | - Jin-Hong Shin
- Department of Neurology, Pusan National University, Yangsan, South Korea
| | - Jung-Joon Sung
- Department of Neurology, Seoul National University, Seoul, South Korea
| | - Byoung Joon Kim
- Department of Neurology, Samsung Medical Center, Seoul, South Korea
| | - Byung-Jo Kim
- Department of Neurology, Korea University Anam Hospital, Seoul, South Korea
| | - Ki-Wook Oh
- Department of Neurology, Hanyang University Hospital, Seoul, South Korea
| | - Kyung Suk Kim
- Central Research Center, Corestem Inc, Seoul, South Korea.
| | - Seung Hyun Kim
- Department of Neurology, Hanyang University Hospital, Seoul, South Korea.
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Bachoud-Lévi AC. What did we learn from neural grafts in Huntington disease? Rev Neurol (Paris) 2022; 178:441-449. [PMID: 35491247 DOI: 10.1016/j.neurol.2022.03.004] [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: 02/25/2022] [Accepted: 03/10/2022] [Indexed: 11/17/2022]
Abstract
Huntington's disease is a rare, severe, and inherited neurodegenerative disorder that affects young adults. To date, there is no treatment to stop its progression. The primary atrophy of the striatum in HD, is limited in space and centrally focalised in the brain and thus constitutes a good candidate for graft. Therefore, transplantation of foetal cells from the ganglionic eminence, the germinal zone of the striatum, has the potential to restore disrupted fronto-cortical circuits and corresponding clinical functions. The international Multicentric intracerebral Grafting in Huntington's disease trial was not as successful as two pilot trials (Créteil and London) which showed promising results in the 2000s, displaying stabilisation/recovery of symptoms in some patients. A point-by-point comparison of the differences between MIG-HD and the pilot trial from Créteil in which similar data are available provides lessons on the grafting procedure and allows for strategic thinking before embarking on future trials. MIG-HD demonstrated the existence of intracerebral alloimmunisation leading to acute or chronic graft rejection into the brain and showed the limitations of surgical standardisation and immunosuppression. It has also improved the safety of the procedure and provided guidance for the follow-up of future patients. Indeed, even if disease modifiers treatments are currently the focus of intense research, they may not stop or slow the progression of the disease sufficiently, or even be administered in all patients, to prevent brain atrophy in all cases. Although disease-modifying therapies are currently the subject of intense research, they may not stop or slow disease progression sufficiently, or may not be given to all patients to prevent brain atrophy. A combination with intracerebral transplantation to repair the damaged structures may thus prove beneficial. Altogether, pursuing research in intracerebral transplantation remains necessary.
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Affiliation(s)
- A-C Bachoud-Lévi
- Département d'études cognitives, école normale supérieure, PSL University, 75005 Paris, France; Inserm U955, Institut Mondor de Recherche Biomédicale, Equipe E01 NeuroPsychologie Interventionnelle, 94000 Créteil, France; Faculté de médecine, Université Paris-Est Créteil, 94000 Créteil, France; Assistance Publique-Hôpitaux de Paris, National Reference Center for Huntington's Disease, Neurology Department, Henri Mondor-Albert Chenevier Hospital, Créteil, France.
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5
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Drew CJG, Busse M. Considerations for clinical trial design and conduct in the evaluation of novel advanced therapeutics in neurodegenerative disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2022; 166:235-279. [PMID: 36424094 DOI: 10.1016/bs.irn.2022.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The recent advances in the development of potentially disease modifying cell and gene therapies for neurodegenerative disease has resulted in the production of a number of promising novel therapies which are now moving forward to clinical evaluation. The robust evaluation of these therapies pose a significant number of challenges when compared to more traditional evaluations of pharmacotherapy, which is the current mainstay of neurodegenerative disease symptom management. Indeed, there is an inherent complexity in the design and conduct of these trials at multiple levels. Here we discuss specific aspects requiring consideration in the context of investigating novel cell and gene therapies for neurodegenerative disease. This extends to overarching trial designs that could be employed and the factors that underpin design choices such outcome assessments, participant selection and methods for delivery of cell and gene therapies. We explore methods of data collection that may improve efficiency in trials of cell and gene therapy to maximize data sharing and collaboration. Lastly, we explore some of the additional context beyond efficacy evaluations that should be considered to ensure implementation across relevant healthcare settings.
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Affiliation(s)
- Cheney J G Drew
- Centre For Trials Research, Cardiff University, Cardiff, United Kingdom; Brain Repair and Intracranial Neurotherapeutics Unit (BRAIN), College of Biomedical and Life Sciences, Cardiff University, Cardiff, United Kingdom.
| | - Monica Busse
- Centre For Trials Research, Cardiff University, Cardiff, United Kingdom; Brain Repair and Intracranial Neurotherapeutics Unit (BRAIN), College of Biomedical and Life Sciences, Cardiff University, Cardiff, United Kingdom
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6
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Polgar S, Buultjens M, Wijeratne T, Finkelstein DI, Mohamed S, Karimi L. The Placebo Response in Double-Blind Randomised Trials Evaluating Regenerative Therapies for Parkinson's Disease: A Systematic Review and Meta-Analysis. JOURNAL OF PARKINSON'S DISEASE 2022; 12:759-771. [PMID: 35034910 DOI: 10.3233/jpd-212610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
In the field of stem cell technologies, exciting advances are taking place leading to translational research to develop cell-based therapies which may replace dopamine releasing neurons lost in patients with Parkinson's disease (PD). A major influence on trial design has been the assumption that the use of sham operated comparator groups is required in the implementation of randomised double-blind trials to evaluate the placebo response and effects associated with the surgical implantation of cells. The aim of the present review is to identify the improvements in motor functioning and striatal dopamine release in patients with PD who have undergone sham surgery. Of the nine published trials, there was at the designated endpoints, a pooled average improvement of 4.3 units, with 95% confidence interval of 3.1 to 5.6 on the motor subscale of the Unified Parkinson's Disease Scale in the 'OFF' state. This effect size indicates a moderate degree of improvement in the motor functioning of the patients in the sham surgical arms of the trials. Four of the nine trials reported the results of 18F-Fluorodopa PET scans, indicating no improvements of dopaminergic nigrostriatal neurones following sham surgery. Therefore, while the initial randomised trials relying on the use of sham operated controls were justified on methodological grounds, we suggest that the analysis of the evidence generated by the completed and published trials indicates that placebo controlled trials are not necessary to advance and evaluate the safety and efficacy of emerging regenerative therapies for PD.
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Affiliation(s)
- Stephen Polgar
- School of Psychology and Public Health, La Trobe University, Melbourne, VIC, Australia
| | - Melissa Buultjens
- School of Psychology and Public Health, La Trobe University, Melbourne, VIC, Australia
| | | | - David I Finkelstein
- Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia
| | - Sheeza Mohamed
- School of Life Sciences, La Trobe University, Melbourne, VIC, Australia
| | - Leila Karimi
- School of Psychology, RMIT University, Melbourne, VIC, Australia
- The Monash Alfred Psychiatry Research Centre, The Alfred and Monash University Central Clinical School, Monash University, Melbourne, VIC, Australia
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7
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Nuvoli S, Spanu A, Fravolini ML, Bianconi F, Cascianelli S, Madeddu G, Palumbo B. [ 123I]Metaiodobenzylguanidine (MIBG) Cardiac Scintigraphy and Automated Classification Techniques in Parkinsonian Disorders. Mol Imaging Biol 2021; 22:703-710. [PMID: 31309370 DOI: 10.1007/s11307-019-01406-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PURPOSE To provide reliable and reproducible heart/mediastinum (H/M) ratio cut-off values for parkinsonian disorders using two machine learning techniques, Support Vector Machines (SVM) and Random Forest (RF) classifier, applied to [123I]MIBG cardiac scintigraphy. PROCEDURES We studied 85 subjects, 50 with idiopathic Parkinson's disease, 26 with atypical Parkinsonian syndromes (P), and 9 with essential tremor (ET). All patients underwent planar early and delayed cardiac scintigraphy after [123I]MIBG (111 MBq) intravenous injection. Images were evaluated both qualitatively and quantitatively; the latter by the early and delayed H/M ratio obtained from regions of interest (ROIt1 and ROIt2) drawn on planar images. SVM and RF classifiers were finally used to obtain the correct cut-off value. RESULTS SVM and RF produced excellent classification performances: SVM classifier achieved perfect classification and RF also attained very good accuracy. The better cut-off for H/M value was 1.55 since it remains the same for both ROIt1 and ROIt2. This value allowed to correctly classify PD from P and ET: patients with H/M ratio less than 1.55 were classified as PD while those with values higher than 1.55 were considered as affected by parkinsonism and/or ET. No difference was found when early or late H/M ratio were considered separately thus suggesting that a single early evaluation could be sufficient to obtain the final diagnosis. CONCLUSIONS Our results evidenced that the use of SVM and CT permitted to define the better cut-off value for H/M ratios both in early and in delayed phase thus underlining the role of [123I]MIBG cardiac scintigraphy and the effectiveness of H/M ratio in differentiating PD from other parkinsonism or ET. Moreover, early scans alone could be used for a reliable diagnosis since no difference was found between early and late. Definitely, a larger series of cases is needed to confirm this data.
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Affiliation(s)
- Susanna Nuvoli
- Unit of Nuclear Medicine, Department of Medicine, Surgical and Experimental Science, University of Sassari, Viale San Pietro 8, 07100, Sassari, Italy.
| | - Angela Spanu
- Unit of Nuclear Medicine, Department of Medicine, Surgical and Experimental Science, University of Sassari, Viale San Pietro 8, 07100, Sassari, Italy
| | | | | | | | - Giuseppe Madeddu
- Unit of Nuclear Medicine, Department of Medicine, Surgical and Experimental Science, University of Sassari, Viale San Pietro 8, 07100, Sassari, Italy
| | - Barbara Palumbo
- Section of Nuclear Medicine and Health Physics, Department of Surgical and Biomedical Sciences, University of Perugia, Perugia, Italy
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8
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Serrano PE, Bhandari M, Simunovic M. Surgical Culture Shifts and Randomized Clinical Trials. JAMA Netw Open 2021; 4:e2115456. [PMID: 34191001 DOI: 10.1001/jamanetworkopen.2021.15456] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Pablo E Serrano
- Department of Surgery, McMaster University, Hamilton, Ontario, Canada
| | - Mohit Bhandari
- Department of Surgery, McMaster University, Hamilton, Ontario, Canada
| | - Marko Simunovic
- Department of Surgery, McMaster University, Hamilton, Ontario, Canada
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9
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Frisaldi E, Zamfira DA, Benedetti F. The subthalamic nucleus and the placebo effect in Parkinson's disease. HANDBOOK OF CLINICAL NEUROLOGY 2021; 180:433-444. [PMID: 34225946 DOI: 10.1016/b978-0-12-820107-7.00027-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The study of the placebo effect, or response, is related to the investigation of the psychologic component of different therapeutic rituals. The high rate of placebo responses in Parkinson's disease clinical trials provided the impetus for investigating the underlying mechanisms. Ruling out spontaneous remission and regression to the mean through the appropriate experimental designs, genuine psychologic placebo effects have been identified, in which both patients' expectations of therapeutic benefit and learning processes are involved. Specifically, placebo effects are associated with dopamine release in the striatum and changes in neuronal activity in the subthalamic nucleus, substantia nigra pars reticulata, and motor thalamus in Parkinson's disease, as assessed through positron emission tomography and single-neuron recording during deep brain stimulation, respectively. Conversely, verbal suggestions of clinical worsening or drug dose reduction induce nocebo responses in Parkinson's disease, which have been detected at both behavioral and electrophysiologic level. Important implications and applications emerge from this new knowledge. These include better clinical trial designs, whereby patients' expectations should always be assessed, as well as better drug dosage in order to reduce drug intake.
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Affiliation(s)
- Elisa Frisaldi
- Department of Neuroscience, University of Turin Medical School, Turin, Italy
| | | | - Fabrizio Benedetti
- Department of Neuroscience, University of Turin Medical School, Turin, Italy; Medicine and Physiology of Hypoxia, Plateau Rosà, Switzerland
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10
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London AJ, Kimmelman J. Clinical Trial Portfolios: A Critical Oversight in Human Research Ethics, Drug Regulation, and Policy. Hastings Cent Rep 2019; 49:31-41. [DOI: 10.1002/hast.1034] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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11
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Barker RA. Designing stem-cell-based dopamine cell replacement trials for Parkinson's disease. Nat Med 2019; 25:1045-1053. [PMID: 31263283 DOI: 10.1038/s41591-019-0507-2] [Citation(s) in RCA: 111] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 06/03/2019] [Indexed: 02/07/2023]
Abstract
Clinical studies of Parkinson's disease (PD) using a dopamine cell replacment strategy have been tried for more than 30 years. The outcomes following transplantation of human fetal ventral mesencephalic tissue (hfVM) have been variable, with some patients coming off their anti-PD treatment for many years and others not responding and/or developing significant side effects, including graft-induced dyskinesia. This led to a re-appraisal of the best way to do such trials, which resulted in a new European-Union-funded allograft trial with fetal dopamine cells across several centers in Europe. This new trial, TRANSEURO ( NCT01898390 ), is an open-label study in which some individuals in a large observational cohort of patients with mild PD who were undergoing identical assessments were randomly selected to receive transplants of hfVM. The TRANSEURO trial is currently ongoing as researchers have completed both recruitment into a large multicenter observational study of younger onset early-stage PD and transplantation of hfVM in 11 patients. While completion of TRANSEURO is not expected until 2021, we feel that sharing the rationale for the design of TRANSEURO, along with the lessons we have learned along the way, can help inform researchers and facilitate planning of transplants of dopamine-producing cells derived from human pluripotent stem cells for future clinical trials.
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Affiliation(s)
- Roger A Barker
- John van Geest Centre for Brain Repair, Department of Clinical Neurosciences and WT-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK.
- John van Geest Centre for Brain Repair, Cambridge University, Cambridge, UK.
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12
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Network imaging biomarkers: insights and clinical applications in Parkinson's disease. Lancet Neurol 2019; 17:629-640. [PMID: 29914708 DOI: 10.1016/s1474-4422(18)30169-8] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 04/13/2018] [Accepted: 04/25/2018] [Indexed: 12/14/2022]
Abstract
Parkinson's disease presents several practical challenges: it can be difficult to distinguish from atypical parkinsonian syndromes, clinical ratings can be insensitive as markers of disease progression, and its non-motor manifestations are not readily assessed in animal models. These challenges, along with others, are beginning to be addressed by innovative imaging methods to characterise Parkinson's disease-specific functional networks across the whole brain and measure their expression in each patient. These signatures can help improve differential diagnosis, guide selection of patients for clinical trials, and quantify treatment responses and placebo effects in individual patients. The primary Parkinson's disease-related metabolic pattern has been replicated in multiple patient populations and used as an outcome measure in clinical trials. It can also be used as a predictor of near-term phenoconversion in prodromal syndromes, such as rapid eye movement sleep behaviour disorder. Functional network imaging holds great promise for future clinical use in the management of neurodegenerative disorders.
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13
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Polgar S, Mohamed S. Evidence-Based Evaluation of the Ethics of Sham Surgery for Parkinson's Disease. JOURNAL OF PARKINSON'S DISEASE 2019; 9:565-574. [PMID: 31282423 PMCID: PMC6700614 DOI: 10.3233/jpd-191577] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Accepted: 05/28/2019] [Indexed: 12/29/2022]
Abstract
The stated purpose of sham or placebo surgery is to enable the implementation of surgical placebo-controlled trials (SPTs) for evaluating the safety and efficacy of surgical interventions. Exposing the participants to the burdens and harms of sham surgery has been justified on the grounds of the absolute necessity for controlling large placebo effects and observer bias, assumed to be associated with surgical procedures. In the present review, we argue that evidence obtained from SPTs of cellular therapies for the treatment of Parkinson's disease (PD) has failed to demonstrate either large and consistent placebo effects or decisive methodological advantages for relying on sham surgical controls. We outline several alternative assessment strategies and designs available to establish the efficacy of cellular therapies. It is concluded that the evidence evaluated in the present analysis indicated that use of sham surgery in the context of developing novel surgical procedures for PD is not necessary, and therefore, unethical under a utilitarian model.
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Affiliation(s)
- Stephen Polgar
- School of Public Health and Psychology, La Trobe University, Bundoora, Melbourne, Australia
| | - Sheeza Mohamed
- School of Life Sciences, La Trobe University, Bundoora, Melbourne, Australia
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Niethammer M, Eidelberg D. Network Imaging in Parkinsonian and Other Movement Disorders: Network Dysfunction and Clinical Correlates. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2019; 144:143-184. [DOI: 10.1016/bs.irn.2018.10.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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15
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Niethammer M, Tang CC, Vo A, Nguyen N, Spetsieris P, Dhawan V, Ma Y, Small M, Feigin A, During MJ, Kaplitt MG, Eidelberg D. Gene therapy reduces Parkinson’s disease symptoms by reorganizing functional brain connectivity. Sci Transl Med 2018; 10:10/469/eaau0713. [DOI: 10.1126/scitranslmed.aau0713] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 09/05/2018] [Accepted: 11/08/2018] [Indexed: 12/24/2022]
Abstract
Gene therapy is emerging as a promising approach for treating neurological disorders, including Parkinson’s disease (PD). A phase 2 clinical trial showed that delivering glutamic acid decarboxylase (GAD) into the subthalamic nucleus (STN) of patients with PD had therapeutic effects. To determine the mechanism underlying this response, we analyzed metabolic imaging data from patients who received gene therapy and those randomized to sham surgery, all of whom had been scanned preoperatively and at 6 and 12 months after surgery. Those who receivedGADgene therapy developed a unique treatment-dependent polysynaptic brain circuit that we termed as theGAD–related pattern (GADRP), which reflected the formation of new polysynaptic functional pathways linking the STN to motor cortical regions. Patients in both the treatment group and the sham group expressed the previously reported placebo network (the sham surgery–related pattern or SSRP) when blinded to the treatment received. However, only the appearance of the GADRP correlated with clinical improvement in the gene therapy–treated subjects. Treatment-induced brain circuits can thus be useful in clinical trials for isolating true treatment responses and providing insight into their underlying biological mechanisms.
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Witek N, Stebbins GT, Goetz CG. What influences placebo and nocebo responses in Parkinson's disease? Mov Disord 2018; 33:1204-1212. [DOI: 10.1002/mds.27416] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 03/27/2018] [Accepted: 03/29/2018] [Indexed: 12/17/2022] Open
Affiliation(s)
- Natalie Witek
- Rush Parkinson's Disease and Movement Disorders Program; Chicago Illinois USA
| | - Glenn T. Stebbins
- Rush Parkinson's Disease and Movement Disorders Program; Chicago Illinois USA
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Polgar S, Karimi L, Buultjens M, Morris ME, Busse M. Assessing the Efficacy of Cell Transplantation for Parkinson's Disease: A Patient-Centered Approach. JOURNAL OF PARKINSON'S DISEASE 2018; 8:375-383. [PMID: 29889080 PMCID: PMC6130410 DOI: 10.3233/jpd-181309] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Accepted: 04/17/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND Evidence from a growing number of preclinical studies indicate that recently discovered stem cell lines may be translated into viable cellular therapies for people with Parkinson's disease. OBJECTIVES In a brief but critical review, we examine the use of primary and secondary outcome measures currently used to evaluate the efficacy of cellular therapies. METHODS The current practice of relying on a single primary outcome measure does not appear to provide the evidence required for demonstrating the robust, life-changing recovery anticipated with the successful implementation of cellular therapies. RESULTS We propose a 360-degree assessment protocol, which includes co-primary and composite outcome measures to provide accurate and comprehensive evidence of treatment efficacy, from the perspectives of both the researchers and the patients.
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Affiliation(s)
- Stephen Polgar
- School of Allied Health, La Trobe University, Bundoora, Melbourne, Australia
| | - Leila Karimi
- School of Psychology and Public Health, La Trobe University, Bundoora, Melbourne, Australia
- School of Health Policy and Management, Ilia State University, Georgia
| | - Melissa Buultjens
- School of Psychology and Public Health, La Trobe University, Bundoora, Melbourne, Australia
| | - Meg E. Morris
- La Trobe Centre for Sport and Exercise Medicine Research, School Allied Health, La Trobe University and Healthscope, Bundoora, Melbourne, Australia
| | - Monica Busse
- Centre For Trials Research, Cardiff University, Cardiff, UK
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18
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Cote DJ, Balak N, Brennum J, Holsgrove DT, Kitchen N, Kolenda H, Moojen WA, Schaller K, Robe PA, Mathiesen T, Broekman ML. Ethical difficulties in the innovative surgical treatment of patients with recurrent glioblastoma multiforme. J Neurosurg 2017; 126:2045-2050. [PMID: 28430037 DOI: 10.3171/2016.11.jns162488] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- David J Cote
- Cushing Neurosurgical Outcomes Center, Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Naci Balak
- Department of Neurosurgery, Göztepe Education and Research Hospital, Istanbul, Turkey
| | - Jannick Brennum
- Department of Neurosurgery, Rigshopsitalet, University of Copenhagen, Denmark
| | - Daniel T Holsgrove
- Department of Neurosurgery, Salford Royal Hospital, Salford, United Kingdom
| | - Neil Kitchen
- The National Hospital for Neurology and Neurosurgery, Queen Square, London, United Kingdom
| | - Herbert Kolenda
- Department of Neurosurgery, Agaplesion Diakonieklinikum, Rotenburg, Germany
| | - Wouter A Moojen
- Department of Neurosurgery, Leiden University Medical Center, Leiden, The Netherlands.,Department of Neurosurgery, Medical Center Haaglanden, The Hague, The Netherlands
| | | | - Pierre A Robe
- Department of Neurosurgery, University Medical Center, Utrecht, The Netherlands
| | - Tiit Mathiesen
- Department of Neurosurgery, Karolinska Institute, Stockholm, Sweden ; and
| | - Marike L Broekman
- Department of Neurosurgery, University Medical Center, Utrecht, The Netherlands.,Department of Neurology, Massachusetts General Hospital, Boston, Massachusetts
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19
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From open to large-scale randomized cell transplantation trials in Huntington's disease. PROGRESS IN BRAIN RESEARCH 2017; 230:227-261. [DOI: 10.1016/bs.pbr.2016.12.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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20
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Kirkeby A, Parmar M, Barker RA. Strategies for bringing stem cell-derived dopamine neurons to the clinic. PROGRESS IN BRAIN RESEARCH 2017; 230:165-190. [DOI: 10.1016/bs.pbr.2016.11.011] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Kim SY, Wilson R, De Vries R, Ryan KA, Holloway RG, Kieburtz K. Are patients with amyotrophic lateral sclerosis at risk of a therapeutic misconception? JOURNAL OF MEDICAL ETHICS 2016; 42:514-518. [PMID: 26964569 DOI: 10.1136/medethics-2015-103319] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 02/17/2016] [Indexed: 06/05/2023]
Abstract
OBJECTIVES To assess whether persons with amyotrophic lateral sclerosis (ALS) are at risk of a therapeutic misconception (TM) in which they misconceive research as treatment or overestimate the likelihood of its benefit. METHODS 72 patients with ALS recruited via academic and patient organisations were surveyed using a hypothetical first-in-human intervention study scenario. We elicited their understanding of the purpose of the study ('purpose-of-research question') and then asked how they interpreted the question. We then asked for an estimate of the likelihood that their ALS would improve by participating and asked them to explain the meaning of their estimates. RESULTS Although 10 of 72 (14%) subjects incorrectly said that the intervention study was 'mostly intending to help [me]' in response to the purpose-of-research question, 7 of those 10 thought that the question was asking them about their own motivations for participating. Overall, only one of 72 respondents (1.4%) both understood the purpose-of-research question as intended and gave the incorrect response. Subjects' mean estimate of likelihood of benefit was 31% (SD 26). This was due to 29 of 72 of respondents providing high estimates (50%-54% likelihood), which they said were expressions of hope and need for a positive attitude; among those who said their estimates meant 'those are the facts' or 'there is a lot of uncertainty', the estimates were much lower (12.6% and 18.5%, respectively). CONCLUSIONS In this group of patients with ALS considering a hypothetical first-in-human intervention study, apparent TM responses have alternative explanations and the risk of true TM appears low.
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Affiliation(s)
- Scott Yh Kim
- Department of Bioethics, National Institutes of Health, Bethesda, Maryland, USA
| | - Renee Wilson
- Center for Human Experimental Therapeutics, University of Rochester, Rochester, NY, USA
| | - Raymond De Vries
- Department of Learning Health Sciences, University of Michigan, Ann Arbor, MI, USA Center for Bioethics and Social Sciences in Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Kerry A Ryan
- Center for Bioethics and Social Sciences in Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Robert G Holloway
- Department of Neurology, University of Rochester, Rochester, NY, USA
| | - Karl Kieburtz
- Department of Neurology, University of Rochester, Rochester, NY, USA Clinical and Translational Science Institute, University of Rochester, Rochester, NY, USA
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22
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Polgar S, Karimi L, Buultjens M, Morris ME. A Critical Evaluation of the Methodological Obstacles to Translating Cell-Based Research Into an Effective Treatment for People With Parkinson's Disease. Neurorehabil Neural Repair 2016; 30:845-53. [PMID: 26944320 DOI: 10.1177/1545968316635277] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The remarkable scientific and technological advances in the field of cell research have not been translated into viable restorative therapies for brain disorders. In this article, we examine the best available evidence for the clinical efficacy of reconstructive intracerebral transplantation in people with Parkinson's disease (PD), with the aim of identifying methodological obstacles to the translation process. The major stumbling block is the fact that the potential contributions of people with neural grafts and the effects of the physical and social environment in which they recover have not been adequately investigated and applied to advancing the clinical stages of the research program. We suggest that the biopsychosocial model along with emerging evidence of targeted rehabilitation can provide a useful framework for conducting research and evaluation that will ensure the best possible outcomes following intracerebral transplantation for PD.
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Affiliation(s)
| | - Leila Karimi
- La Trobe University, Melbourne, Australia Ilia State University, Georgia
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23
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Kuan WL, Kasis A, Yuan Y, Mason SL, Lazar AS, Barker RA, Goncalves J. Modelling the natural history of Huntington's disease progression. J Neurol Neurosurg Psychiatry 2015; 86:1143-9. [PMID: 25515501 DOI: 10.1136/jnnp-2014-308153] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 11/23/2014] [Indexed: 11/04/2022]
Abstract
BACKGROUND The lack of reliable biomarkers to track disease progression is a major problem in clinical research of chronic neurological disorders. Using Huntington's disease (HD) as an example, we describe a novel approach to model HD and show that the progression of a neurological disorder can be predicted for individual patients. METHODS Starting with an initial cohort of 343 patients with HD that we have followed since 1995, we used data from 68 patients that satisfied our filtering criteria to model disease progression, based on the Unified Huntington's Disease Rating Scale (UHDRS), a measure that is routinely used in HD clinics worldwide. RESULTS Our model was validated by: (A) extrapolating our equation to model the age of disease onset, (B) testing it on a second patient data set by loosening our filtering criteria, (C) cross-validating with a repeated random subsampling approach and (D) holdout validating with the latest clinical assessment data from the same cohort of patients. With UHDRS scores from the past four clinical visits (over a minimum span of 2 years), our model predicts disease progression of individual patients over the next 2 years with an accuracy of 89-91%. We have also provided evidence that patients with similar baseline clinical profiles can exhibit very different trajectories of disease progression. CONCLUSIONS This new model therefore has important implications for HD research, most obviously in the development of potential disease-modifying therapies. We believe that a similar approach can also be adapted to model disease progression in other chronic neurological disorders.
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Affiliation(s)
- W L Kuan
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Cambridge, UK
| | - A Kasis
- Department of Engineering, University of Cambridge, Cambridge, UK
| | - Y Yuan
- Department of Engineering, University of Cambridge, Cambridge, UK
| | - S L Mason
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Cambridge, UK
| | - A S Lazar
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Cambridge, UK
| | - R A Barker
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, Cambridge, UK
| | - J Goncalves
- Department of Engineering, University of Cambridge, Cambridge, UK Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Walferdange, Luxembourg
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24
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Ko JH, Feigin A, Mattis PJ, Tang CC, Ma Y, Dhawan V, During MJ, Kaplitt MG, Eidelberg D. Network modulation following sham surgery in Parkinson's disease. J Clin Invest 2014; 124:3656-66. [PMID: 25036712 DOI: 10.1172/jci75073] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 05/08/2014] [Indexed: 02/01/2023] Open
Abstract
Patient responses to placebo and sham effects are a major obstacle to the development of therapies for brain disorders, including Parkinson's disease (PD). Here, we used functional brain imaging and network analysis to study the circuitry underlying placebo effects in PD subjects randomized to sham surgery as part of a double-blind gene therapy trial. Metabolic imaging was performed prior to randomization, then again at 6 and 12 months after sham surgery. In this cohort, the sham response was associated with the expression of a distinct cerebello-limbic circuit. The expression of this network increased consistently in patients blinded to treatment and correlated with independent clinical ratings. Once patients were unblinded, network expression declined toward baseline levels. Analogous network alterations were not seen with open-label levodopa treatment or during disease progression. Furthermore, sham outcomes in blinded patients correlated with baseline network expression, suggesting the potential use of this quantitative measure to identify "sham-susceptible" subjects before randomization. Indeed, Monte Carlo simulations revealed that a priori exclusion of such individuals substantially lowers the number of randomized participants needed to demonstrate treatment efficacy. Individualized subject selection based on a predetermined network criterion may therefore limit the need for sham interventions in future clinical trials.
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25
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Frisaldi E, Carlino E, Lanotte M, Lopiano L, Benedetti F. Characterization of the thalamic-subthalamic circuit involved in the placebo response through single-neuron recording in Parkinson patients. Cortex 2013; 60:3-9. [PMID: 24457096 DOI: 10.1016/j.cortex.2013.12.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Revised: 08/05/2013] [Accepted: 12/10/2013] [Indexed: 10/25/2022]
Abstract
The placebo effect, or response, is a complex phenomenon whereby an inert treatment can induce a therapeutic benefit if the subject is made to believe that it is effective. One of the main mechanisms involved is represented by expectations of clinical improvement which, in turn, have been found to either reduce anxiety or activate reward mechanisms. Therefore, the study of the placebo effect allows us to understand how emotions may affect both behavior and therapeutic outcome. The high rate of placebo responders in clinical trials of Parkinson's disease provided the motivation to investigate the biological underpinnings of the placebo response in Parkinsonian patients. The placebo effect in Parkinson's disease is induced through the administration of an inert substance which the patient believes to improve motor performance. By using this approach, different behavioral and neuroimaging studies have documented objective improvements in motor performance and an increase of endogenous dopamine release in both the dorsal and ventral striatum. Recently, single-neuron recording from the subthalamic and thalamic regions during the implantation of electrodes for deep brain stimulation has been used to investigate the firing pattern of different neurons before and after placebo administration. The results show that the subthalamic nucleus, the substantia nigra pars reticulata, and the ventral anterior thalamus are all involved in the placebo response in Parkinson patients, thus making intraoperative recording an excellent model to characterize the neuronal circuit that is involved in the placebo response in Parkinson's disease as well as in other disorders of movement.
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Affiliation(s)
- Elisa Frisaldi
- Department of Neuroscience, University of Turin Medical School, Turin, Italy; National Institute of Neuroscience, Turin, Italy
| | - Elisa Carlino
- Department of Neuroscience, University of Turin Medical School, Turin, Italy; National Institute of Neuroscience, Turin, Italy
| | - Michele Lanotte
- Department of Neuroscience, University of Turin Medical School, Turin, Italy
| | - Leonardo Lopiano
- Department of Neuroscience, University of Turin Medical School, Turin, Italy
| | - Fabrizio Benedetti
- Department of Neuroscience, University of Turin Medical School, Turin, Italy; National Institute of Neuroscience, Turin, Italy.
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26
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Forcelli PA, Kalikhman D, Gale K. Delayed effect of craniotomy on experimental seizures in rats. PLoS One 2013; 8:e81401. [PMID: 24324691 PMCID: PMC3852486 DOI: 10.1371/journal.pone.0081401] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 10/21/2013] [Indexed: 12/02/2022] Open
Abstract
Neurosurgical therapeutic interventions include components that are presumed to be therapeutically inert, such as craniotomy and electrode implantation. Because these procedures may themselves exert neuroactive actions, with anecdotal evidence suggesting that craniotomy and electrode placement may have a particularly significant impact on epileptic seizures, the importance of their inclusion in sham control groups has become more compelling. Here we set out to test the hypothesis that craniotomy alone is sufficient to alter experimental seizures in rats. We tested adult male rats for seizures evoked by pentylenetetrazole (70 mg/kg) between 3 and 20 days following placement of bilateral craniotomies (either 2.5 or 3.5 mm in diameter) in the parietal bone of the skull, without penetrating the dura. Control (sham-operated) animals underwent anesthesia and surgery without craniotomy. We found that craniotomy significantly decreased the severity of experimental seizures on postoperative days 3, 6, and 10; this effect was dependent on the size of craniotomy. Animals with craniotomies returned to control seizure severity by 20 days post-craniotomy. These data support the hypothesis that damage to the skull is sufficient to cause a significant alteration in seizure susceptibility over an extended postoperative period, and indicate that this damage should not be considered neurologically inert.
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Affiliation(s)
- Patrick A. Forcelli
- Department of Pharmacology and Physiology, Georgetown University, Washington, District of Columbia, United States of America
| | - David Kalikhman
- Department of Pharmacology and Physiology, Georgetown University, Washington, District of Columbia, United States of America
| | - Karen Gale
- Department of Pharmacology and Physiology, Georgetown University, Washington, District of Columbia, United States of America
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27
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Barker RA, de Beaufort I. Scientific and ethical issues related to stem cell research and interventions in neurodegenerative disorders of the brain. Prog Neurobiol 2013; 110:63-73. [DOI: 10.1016/j.pneurobio.2013.04.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 04/04/2013] [Accepted: 04/12/2013] [Indexed: 12/13/2022]
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28
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Chen WW, Blurton-Jones M. Concise review: Can stem cells be used to treat or model Alzheimer's disease? Stem Cells 2013; 30:2612-8. [PMID: 22997040 DOI: 10.1002/stem.1240] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Accepted: 09/03/2012] [Indexed: 12/23/2022]
Abstract
Alzheimer's disease (AD) is the leading cause of age-related dementia, affecting over 5 million people in the U.S. alone. AD patients suffer from progressive neurodegeneration that gradually impairs their memory, ability to learn, and carry out daily activities. Unfortunately, current therapies for AD are largely palliative and several promising drug candidates have failed in recent clinical trials. There is therefore an urgent need to improve our understanding of AD pathogenesis, create innovative and predictive models, and develop new and effective therapies. In this review, we will discuss the potential of stem cells to aid in these challenging endeavors. Because of the widespread nature of AD pathology, cell-replacement strategies have been viewed as an incredibly challenging and unlikely treatment approach. Yet recent work shows that transplantation of neural stem cells (NSCs) can improve cognition, reduce neuronal loss, and enhance synaptic plasticity in animal models of AD. Interestingly, the mechanisms that mediate these effects appear to involve neuroprotection and trophic support rather than neuronal replacement. Stem cells may also offer a powerful new approach to model and study AD. Patient-derived induced pluripotent stem cells, for example, may help to advance our understanding of disease mechanisms. Likewise, studies of human embryonic and NSCs are helping to decipher the normal functions of AD-related genes; revealing intriguing roles in neural development.
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Affiliation(s)
- Wesley W Chen
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, California 92697-4545, USA
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Barker RA, Stacy M, Brundin P. A new approach to disease-modifying drug trials in Parkinson's disease. J Clin Invest 2013; 123:2364-5. [PMID: 23728166 DOI: 10.1172/jci69690] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Translating new findings in the laboratory into therapies for patients is a slow and expensive process. The development of therapies for neurodegenerative diseases is further complicated by the difficulty in determining whether the drug truly retards the slow degenerative process or provides only symptomatic benefit. In this issue, Aviles-Olmos et al. describe a first in Parkinson's disease (PD) patient study using a drug previously approved for diabetes treatment. In addition to suggesting that the drug may indeed be disease modifying in PD, their innovative approach suggests there may be more rapid and inexpensive avenues for testing novel therapies in PD.
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Affiliation(s)
- Roger A Barker
- Department of Neurology and Clinical Neurosciences, Cambridge Center for Brain Repair, University of Cambridge, Cambridge, United Kingdom
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30
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Murray D, Stoessl AJ. Mechanisms and therapeutic implications of the placebo effect in neurological and psychiatric conditions. Pharmacol Ther 2013; 140:306-18. [PMID: 23880289 DOI: 10.1016/j.pharmthera.2013.07.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 07/09/2013] [Indexed: 12/19/2022]
Abstract
The power of a placebo to effect clinically meaningful neurobiological change comparable to pharmacological therapies has been demonstrated, although the mechanisms are not fully understood. Predicting placebo responsiveness has only recently received more attention, but psychological disposition, contextual and biological factors are now known to dramatically affect a person's susceptibility to the placebo effect. The placebo effect depends upon expectancies that can be modified in a number of ways, including conditioning through explicit or implicit learned associations. Based on the dopaminergic response to anticipation of benefit in Parkinson's disease, it was suggested that the placebo effect can be seen as analogous to the expectation of reward. Dopaminergic pathways have since been implicated in the placebo response in pain and depression. Additionally, endogenous opioid release is known to mediate many forms of placebo analgesia. We provide an overview of the mechanisms and the therapeutic implications of the placebo effect in neurological and psychiatric conditions. We include evidence for detrimental effects arising from seemingly inert interventions, termed the 'nocebo effect.' Neuroimaging has critically advanced the study of the placebo effect and provides some of the strongest evidence for the mechanisms of this phenomenon prevalent across an array of human health-related circumstances. This review specifically focuses on mechanisms of the placebo effect in the three conditions that have most significantly demonstrated this effect and for which a plausible physiological basis can be identified: pain, PD and depression. Other neurological and psychiatric diseases reviewed include multiple sclerosis, Huntington's disease, Alzheimer's disease, schizophrenia and epilepsy.
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Affiliation(s)
- Danielle Murray
- Pacific Parkinson's Research Centre and Department of Medicine, Division of Neurology, University of British Columbia & Vancouver Coastal Health, Canada
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31
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Stem cells and the treatment of Parkinson's disease. Exp Neurol 2013; 260:3-11. [PMID: 23298521 DOI: 10.1016/j.expneurol.2012.12.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2012] [Revised: 12/18/2012] [Accepted: 12/26/2012] [Indexed: 02/06/2023]
Abstract
Progress in Parkinson's disease (PD) research has been hampered by the lack of an appropriate model which exhibits the core pathology seen in the human brain. Recent advances in deriving cells with neuronal phenotypes from patients with neurodegenerative disorders through cellular reprogramming offer a unique tool for disease modelling and may help shed light on the molecular pathogenesis that drives the progression of the disease. This technology may also help in establishing platforms for drug screening and open up exciting new prospects for cell grafting. In this review, we will discuss progress made in differentiating stem cells into authentic dopamine neurons and where we stand with respect to clinical trials with these cells in patients with PD. We will also examine the various approaches used in cellular reprogramming and their differentiation into patient-specific midbrain dopamine neurons, with an emphasis particularly on modelling familial cases of PD to recapitulate disease phenotypes. This review will highlight some of the challenges that need to be addressed for this technology to have any potential clinical application in cell therapy and personalised medicine.
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32
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Cohen PD, Isaacs T, Willocks P, Herman L, Stamford J, Riggare S, Wittekind P. Sham neurosurgical procedures: the patients' perspective. Lancet Neurol 2012; 11:1022. [DOI: 10.1016/s1474-4422(12)70277-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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33
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Granger N, Blamires H, Franklin RJM, Jeffery ND. Autologous olfactory mucosal cell transplants in clinical spinal cord injury: a randomized double-blinded trial in a canine translational model. Brain 2012; 135:3227-37. [PMID: 23169917 PMCID: PMC3501977 DOI: 10.1093/brain/aws268] [Citation(s) in RCA: 123] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 08/24/2012] [Accepted: 08/27/2012] [Indexed: 12/24/2022] Open
Abstract
This study was designed to determine whether an intervention proven effective in the laboratory to ameliorate the effects of experimental spinal cord injury could provide sufficient benefit to be of value to clinical cases. Intraspinal olfactory ensheathing cell transplantation improves locomotor outcome after spinal cord injury in 'proof of principle' experiments in rodents, suggesting the possibility of efficacy in human patients. However, laboratory animal spinal cord injury cannot accurately model the inherent heterogeneity of clinical patient cohorts, nor are all aspects of their spinal cord function readily amenable to objective evaluation. Here, we measured the effects of intraspinal transplantation of cells derived from olfactory mucosal cultures (containing a mean of ~50% olfactory ensheathing cells) in a population of spinal cord-injured companion dogs that accurately model many of the potential obstacles involved in transition from laboratory to clinic. Dogs with severe chronic thoracolumbar spinal cord injuries (equivalent to ASIA grade 'A' human patients at ~12 months after injury) were entered into a randomized double-blinded clinical trial in which they were allocated to receive either intraspinal autologous cells derived from olfactory mucosal cultures or injection of cell transport medium alone. Recipients of olfactory mucosal cell transplants gained significantly better fore-hind coordination than those dogs receiving cell transport medium alone. There were no significant differences in outcome between treatment groups in measures of long tract functionality. We conclude that intraspinal olfactory mucosal cell transplantation improves communication across the damaged region of the injured spinal cord, even in chronically injured individuals. However, we find no evidence for concomitant improvement in long tract function.
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Affiliation(s)
- Nicolas Granger
- 1 Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, UK
| | - Helen Blamires
- 1 Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, UK
| | - Robin J. M. Franklin
- 1 Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, UK
- 2 Cambridge Stem Cell Institute, University of Cambridge, UK
| | - Nick D. Jeffery
- 1 Department of Veterinary Medicine, University of Cambridge, Cambridge, CB3 0ES, UK
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