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Conklin C, Scott D, Bracoud L, Vuksanovic V, Wischik CM, Suhy J, Staff R. Template impact in nucleus basalis segmentation. Alzheimers Dement 2021. [DOI: 10.1002/alz.053912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Shiells H, Schelter BO, Bentham P, Baddeley TC, Rubino CM, Ganesan H, Hammel J, Vuksanovic V, Staff RT, Murray AD, Bracoud L, Wischik DJ, Riedel G, Gauthier S, Jia J, Moebius HJ, Hardlund J, Kipps CM, Kook K, Storey JMD, Harrington CR, Wischik CM. Concentration-Dependent Activity of Hydromethylthionine on Clinical Decline and Brain Atrophy in a Randomized Controlled Trial in Behavioral Variant Frontotemporal Dementia. J Alzheimers Dis 2021; 75:501-519. [PMID: 32280089 PMCID: PMC7306898 DOI: 10.3233/jad-191173] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND Hydromethylthionine is a potent inhibitor of pathological aggregation of tau and TDP-43 proteins. OBJECTIVE To compare hydromethylthionine treatment effects at two doses and to determine how drug exposure is related to treatment response in bvFTD. METHODS We undertook a 52-week Phase III study in 220 bvFTD patients randomized to compare hydromethylthionine at 200 mg/day and 8 mg/day (intended as a control). The principal outcomes were change on the Addenbrookes Cognitive Examination - Revised (ACE-R), the Functional Activities Questionnaire (FAQ), and whole brain volume. Secondary outcomes included Modified Clinical Global Impression of Change (Modified-CGIC). A population pharmacokinetic exposure-response analysis was undertaken in 175 of the patients with available blood samples and outcome data using a discriminatory plasma assay for the parent drug. RESULTS There were no significant differences between the two doses as randomized. There were steep concentration-response relationships for plasma levels in the range 0.3-0.6 ng/ml at the 8 mg/day dose on clinical and MRI outcomes. There were significant exposure-dependent differences at 8 mg/day for FAQ, Modified-CGIC, and whole brain atrophy comparing patients with plasma levels greater than 0.346 ng/ml with having minimal drug exposure. The exposure-response is biphasic with worse outcomes at the high concentrations produced by 200 mg/day. CONCLUSIONS Hydromethylthionine has a similar concentration-response profile for effects on clinical decline and brain atrophy at the 8 mg/day dose in bvFTD as recently reported in AD. Treatment responses in bvFTD are predicted to be maximal at doses in the range 20-60 mg/day. A confirmatory placebo-controlled trial is now planned.
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Affiliation(s)
| | - Bjoern O Schelter
- TauRx Therapeutics Ltd., Aberdeen, UK.,Institute for Complex Systems and Mathematical Biology, University of Aberdeen, Aberdeen, UK
| | | | - Thomas C Baddeley
- TauRx Therapeutics Ltd., Aberdeen, UK.,Department of Chemistry, University of Aberdeen, Aberdeen, UK
| | | | - Harish Ganesan
- Institute of Clinical Pharmacodynamics, Schenectady, NY, USA
| | - Jeffrey Hammel
- Institute of Clinical Pharmacodynamics, Schenectady, NY, USA
| | - Vesna Vuksanovic
- Aberdeen Biomedical Imaging Centre, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Roger T Staff
- Aberdeen Royal Infirmary, NHS Grampian, Aberdeen, UK
| | - Alison D Murray
- Aberdeen Biomedical Imaging Centre, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | | | - Damon J Wischik
- TauRx Therapeutics Ltd., Aberdeen, UK.,Department of Computer Science and Technology, University of Cambridge, Cambridge, UK
| | - Gernot Riedel
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Serge Gauthier
- McGill Centre for Studies in Aging, Alzheimer's Disease Research Unit, and Douglas Mental Health University Institute, Montreal, QC, Canada
| | - Jianping Jia
- Beijing Institute for Brain Disorders Alzheimer's Disease Centre, Beijing, China
| | | | | | | | | | - John M D Storey
- TauRx Therapeutics Ltd., Aberdeen, UK.,Department of Chemistry, University of Aberdeen, Aberdeen, UK
| | - Charles R Harrington
- TauRx Therapeutics Ltd., Aberdeen, UK.,School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Claude M Wischik
- TauRx Therapeutics Ltd., Aberdeen, UK.,School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, UK
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Vuksanovic V, Staff R, Ahearn T, Murray AD, Wischik C. Imaging profiles of Alzheimer’s disease and behavioural variant frontotemporal dementia based on cortical structural correlation networks. Alzheimers Dement 2020. [DOI: 10.1002/alz.041733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Schelter BO, Shiells H, Baddeley TC, Rubino CM, Ganesan H, Hammel J, Vuksanovic V, Staff RT, Murray AD, Bracoud L, Riedel G, Gauthier S, Jia J, Bentham P, Kook K, Storey JM, Harrington CR, Wischik CM. Concentration-Dependent Activity of Hydromethylthionine on Cognitive Decline and Brain Atrophy in Mild to Moderate Alzheimer's Disease. J Alzheimers Dis 2019; 72:931-946. [PMID: 31658058 PMCID: PMC6918900 DOI: 10.3233/jad-190772] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/23/2019] [Indexed: 12/31/2022]
Abstract
BACKGROUND Although hydromethylthionine is a potent tau aggregation inhibitor, no difference was found in either of two Phase III trials in mild to moderate Alzheimer's disease (AD) comparing doses in the range 150-250 mg/day with 8 mg/day intended as a control. OBJECTIVE To determine how drug exposure is related to treatment response. METHODS A sensitive plasma assay for the drug was used in a population pharmacokinetic analysis of samples from 1,162 of the 1,686 patients who participated in either of the Phase III trials with available samples and efficacy outcome data. RESULTS There are steep concentration-response relationships for steady state plasma levels in the range 0.3-0.8 ng/ml at the 8 mg/day dose. Using a threshold based on the lower limit of quantitation of the assay on Day 1, there are highly significant differences in cognitive decline and brain atrophy in patients with above threshold plasma levels, both for monotherapy and add-on therapy, but with effect sizes reduced by half as add-on. Plasma concentrations in the range 4-21 ng/ml produced by the high doses are not associated with any additional benefit. CONCLUSIONS Hydromethylthionine has pharmacological activity on brain structure and function at the 8 mg/day dose as monotherapy or as add-on to symptomatic treatments. This combined with a plateau at higher doses is consistent with the lack of dose-response seen in the Phase III trials. Treatment benefit is predicted to be maximal at 16 mg/day as monotherapy. A placebo-controlled trial in mild/moderate AD is now ongoing to confirm efficacy at this dose.
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Affiliation(s)
- Bjoern O. Schelter
- TauRx Therapeutics Ltd., Singapore, Singapore
- Institute for Complex Systems and Mathematical Biology, University of Aberdeen, Aberdeen, UK
| | | | | | | | - Harish Ganesan
- Institute of Clinical Pharmacodynamics, Schenectady, NY, USA
| | - Jeffrey Hammel
- Institute of Clinical Pharmacodynamics, Schenectady, NY, USA
| | - Vesna Vuksanovic
- Aberdeen Biomedical Imaging Center, University of Aberdeen, Foresterhill, Aberdeen, UK
| | | | - Alison D. Murray
- Aberdeen Biomedical Imaging Center, University of Aberdeen, Foresterhill, Aberdeen, UK
| | | | - Gernot Riedel
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Serge Gauthier
- McGill Centre for Studies in Aging, Alzheimer’s Disease Research Unit, and Douglas Mental Health University Institute, Montreal, QC, Canada
| | - Jianping Jia
- Innovation Center for Neurological Disorders, Neurology Department, Xuanwu Hospital, Capital Medical University, Beijing, China
| | | | | | - John M.D. Storey
- TauRx Therapeutics Ltd., Singapore, Singapore
- Department of Chemistry, University of Aberdeen, Aberdeen, UK
| | - Charles R. Harrington
- TauRx Therapeutics Ltd., Singapore, Singapore
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Claude M. Wischik
- TauRx Therapeutics Ltd., Singapore, Singapore
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Foresterhill, Aberdeen, UK
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Wilcock GK, Gauthier S, Frisoni GB, Jia J, Hardlund JH, Moebius HJ, Bentham P, Kook KA, Schelter BO, Wischik DJ, Davis CS, Staff RT, Vuksanovic V, Ahearn T, Bracoud L, Shamsi K, Marek K, Seibyl J, Riedel G, Storey JMD, Harrington CR, Wischik CM. Potential of Low Dose Leuco-Methylthioninium Bis(Hydromethanesulphonate) (LMTM) Monotherapy for Treatment of Mild Alzheimer's Disease: Cohort Analysis as Modified Primary Outcome in a Phase III Clinical Trial. J Alzheimers Dis 2018; 61:435-457. [PMID: 29154277 PMCID: PMC5734125 DOI: 10.3233/jad-170560] [Citation(s) in RCA: 130] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Background: LMTM is being developed as a treatment for AD based on inhibition of tau aggregation. Objectives: To examine the efficacy of LMTM as monotherapy in non-randomized cohort analyses as modified primary outcomes in an 18-month Phase III trial in mild AD. Methods: Mild AD patients (n = 800) were randomly assigned to 100 mg twice a day or 4 mg twice a day. Prior to unblinding, the Statistical Analysis Plan was revised to compare the 100 mg twice a day as monotherapy subgroup (n = 79) versus 4 mg twice a day as randomized (n = 396), and 4 mg twice a day as monotherapy (n = 76) versus 4 mg twice a day as add-on therapy (n = 297), with strong control of family-wise type I error. Results: The revised analyses were statistically significant at the required threshold of p < 0.025 in both comparisons for change in ADAS-cog, ADCS-ADL, MRI atrophy, and glucose uptake. The brain atrophy rate was initially typical of mild AD in both add-on and monotherapy groups, but after 9 months of treatment, the rate in monotherapy patients declined significantly to that reported for normal elderly controls. Differences in severity or diagnosis at baseline between monotherapy and add-on patients did not account for significant differences in favor of monotherapy. Conclusions: The results are consistent with earlier studies in supporting the hypothesis that LMTM might be effective as monotherapy and that 4 mg twice a day may serve as well as higher doses. A further suitably randomized trial is required to test this hypothesis.
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Affiliation(s)
- Gordon K Wilcock
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Serge Gauthier
- McGill Centre for Studies in Aging, Alzheimer's Disease Research Unit, and Douglas Mental Health University Institute, Montreal, QC, Canada
| | | | - Jianping Jia
- Beijing Institute for Brain Disorders Alzheimer's Disease Centre, Beijing, China
| | | | | | - Peter Bentham
- Birmingham and Solihull Mental Health Foundation Trust, Birmingham, UK
| | | | - Bjoern O Schelter
- Institute for Complex Systems and Mathematical Biology, University of Aberdeen, Aberdeen, UK
| | | | | | - Roger T Staff
- Aberdeen Biomedical Imaging Centre, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Vesna Vuksanovic
- Aberdeen Biomedical Imaging Centre, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Trevor Ahearn
- Aberdeen Biomedical Imaging Centre, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | | | | | | | | | - Gernot Riedel
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - John M D Storey
- TauRx Therapeutics, Aberdeen, UK.,Department of Chemistry, University of Aberdeen, Aberdeen, UK
| | - Charles R Harrington
- TauRx Therapeutics, Aberdeen, UK.,School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
| | - Claude M Wischik
- TauRx Therapeutics, Aberdeen, UK.,School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
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Bartolo MJ, Gieselmann MA, Vuksanovic V, Hunter D, Sun L, Chen X, Delicato LS, Thiele A. Stimulus-induced dissociation of neuronal firing rates and local field potential gamma power and its relationship to the resonance blood oxygen level-dependent signal in macaque primary visual cortex. Eur J Neurosci 2011; 34:1857-70. [PMID: 22081989 PMCID: PMC3274700 DOI: 10.1111/j.1460-9568.2011.07877.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The functional magnetic resonance imaging (fMRI) blood oxygenation level-dependent (BOLD) signal is regularly used to assign neuronal activity to cognitive function. Recent analyses have shown that the local field potential (LFP) gamma power is a better predictor of the fMRI BOLD signal than spiking activity. However, LFP gamma power and spiking activity are usually correlated, clouding the analysis of the neural basis of the BOLD signal. We show that changes in LFP gamma power and spiking activity in the primary visual cortex (V1) of the awake primate can be dissociated by using grating and plaid pattern stimuli, which differentially engage surround suppression and cross-orientation inhibition/facilitation within and between cortical columns. Grating presentation yielded substantial V1 LFP gamma frequency oscillations and significant multi-unit activity. Plaid pattern presentation significantly reduced the LFP gamma power while increasing population multi-unit activity. The fMRI BOLD activity followed the LFP gamma power changes, not the multi-unit activity. Inference of neuronal activity from the fMRI BOLD signal thus requires detailed a priori knowledge of how different stimuli or tasks activate the cortical network.
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Affiliation(s)
- M J Bartolo
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
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Vuksanovic V, Gal V, Kalanj J, Simeunovic S. Effect of posture on heart rate variability spectral measures in children and young adults with heart disease. Int J Cardiol 2005; 101:273-8. [PMID: 15882675 DOI: 10.1016/j.ijcard.2004.03.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2003] [Revised: 12/09/2003] [Accepted: 03/05/2004] [Indexed: 02/05/2023]
Abstract
BACKGROUND Reduction of heart rate variability as a consequence of heart disease and postural change has been well documented. However, the data on the effect of postural change in pediatric patients are incomplete and the effect is not fully understood. The aim of the study was to investigate effect of postural change on heart rate variability in relation to the extent of severity of heart disease. METHODS The dependence of heart rate variability on posture in 41 children and young adults (8-20 years) with heart disease has been investigated and compared with control. Short-term electrocardiograms (ECGs) were assessed in supine rest and active standing, and spectral measures of heart rate variability were determined. RESULTS Two types of response to the change of supine to standing posture were determined in both healthy and diseased subjects. In majority of subjects, the increased heart rate induced by standing was accompanied by a decrease in high-frequency power. However, in about 30% of all subjects, increased heart rate during standing was accompanied by an increased high-frequency power. Independently of posture and disease, high-frequency and low-frequency power were positively correlated. In subjects characterized by a reduction of heart rate variability in standing, the high-frequency power in both postures is reduced in diseased subjects compared to control. CONCLUSIONS These results demonstrate that in this age range, the response to posture is not unique because of the difference in high-frequency power, which implies a variety of vagal modulations of heart rate.
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Affiliation(s)
- Vesna Vuksanovic
- Institute of Biophysics, Faculty of Medicine, University of Belgrade, Visegradska 26/2, Belgrade, Serbia nad Montenegro.
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