scholarly journals DEFORMATION BASED MORPHOMETRY STUDY OF LONGITUDINAL MRI CHANGES IN BEHAVIORAL VARIANT FRONTOTEMPORAL DEMENTIA

2019 ◽  
Author(s):  
Ana L. Manera ◽  
Mahsa Dadar ◽  
D. Louis Collins ◽  
Simon Ducharme ◽  

ABSTRACTObjectiveTo objectively quantify how cerebral volume loss could assist with clinical diagnosis and clinical trial design in the behavioural variant of frontotemporal dementia (bvFTD).MethodsWe applied deformation-based morphometric analyses with robust registration to precisely quantify the magnitude and pattern of atrophy in patients with bvFTD as compared to cognitively normal controls (CNCs), to assess the progression of atrophy over one year follow up and to generate clinical trial sample size estimates to detect differences for the structures most sensitive to change. This study included 203 subjects - 70 bvFTD and 133 CNCs - with a total of 482 timepoints from the Frontotemporal Lobar Degeneration Neuroimaging Initiative.ResultsDeformation based morphometry (DBM) revealed significant atrophy in the frontal lobes, insula, medial and anterior temporal regions bilaterally in bvFTD subjects compared to controls with outstanding subcortical involvement. We provide detailed information on regional changes per year. In both cross-sectional analysis and over a one-year follow-up period, ventricle expansion was the most prominent differentiator of bvFTD from controls and a sensitive marker of disease progression.ConclusionsAutomated measurement of ventricular expansion is a sensitive and reliable marker of disease progression in bvFTD to be used in clinical trials for potential disease modifying drugs, as well as possibly to implement in clinical practice. Ventricular expansion measured with DBM provides the lowest published estimated sample size for clinical trial design to detect significant differences over one and two years.






2013 ◽  
Vol 31 (6_suppl) ◽  
pp. 399-399
Author(s):  
Francesco Massari ◽  
Francesca Maines ◽  
Sara Pilotto ◽  
Maria Bonomi ◽  
Diana Giannarelli ◽  
...  

399 Background: To predict the clinical benefit of TA in mRCC, several studies have analyzed some angiogenesis-related biomarkers including soluble VEGF and VEGF-Receptors, VEGF polymorphisms, IL-8 polymorphisms, and VHL mutations. We performed a power analysis to assess how much a biomarker-based approach can affect the sample size of a trial in mRCC. Methods: Hazard ratios (HR) for survival with 95% confidence intervals (CI) for overall survival were extracted and cumulated according to a random-effect model from RCTs. A sensitivity analysis according to ‘biomarker-selection’ approach and to ‘unselected’ fashion was accomplished in order to test for interaction. Testing for heterogeneity was performed as well. Results: A correlation between a featured biomarker and treatment effect was reported in three RCTs (1987 patients). The attrition rate for the survival analysis according to the molecular analysis was 45% (range 20 to 60%). In spite of the extremely different bio-markers’ profiles, demonstrated by the significant observed heterogeneity (p = 0.002), we found an Hazard Ratio (HR) for overall survival of 0.60 (95% CI 0.40-0.89; p = 0.013) and a significant interaction according to strategy (‘biomarker-selected’ vs.‘unselected’) (p = 0.025), supporting a differential effect of these drugs when administered according to a predictive phenotype. In the ‘unselected’ sample, considering the intention to treat analysis (all randomized patients) the HR was 0.90 (95% 0.80-1.00; p = 0.06). From a clinical trial design perspective, if targeting these expected survival differences, with a power 80%, and a alpha-error 0.05, the required events are described in the table. Conclusions: With the aim to avoid the attrition of the heterogeneity of biomarkers’ selection and drugs, we speculate that the sample size of a planned clinical trial design in mRCC according to a biomolecular classifier may help to shorten the gap between clinical research and practice. [Table: see text]





2019 ◽  
Vol 3 (Supplement_1) ◽  
pp. S745-S745
Author(s):  
Jason L Sanders ◽  
Anne B Newman

Abstract We are on the cusp of a revolution in aging science. It has matured to the point where geroscience trials will test interventions in humans which alter aging mechanisms to lengthen healthspan and possibly lifespan. This goal is unprecedented in clinical trial design, and it requires retooling the clinical trial toolbox. Traditionally, trials are constructed around a single disease; interventions target a narrow part of a defined biological pathway involving only one molecule, tissue, or organ; events are well known intermediate endpoints and clinically-defined hard outcomes; and follow up may be short and historically informed based on prior trials. Geroscience trials by design target aging mechanisms which, when altered, are likely to have pleiotropic effects that modify several biologic pathways; efficacy and safety signals may require integration across multiple levels of biologic organization; intermediate endpoints are not agreed upon; and follow up timelines are undefined. In this symposium, we provide guidance on the design of geroscience trials using examples that span from bench to population science. Dr. LeBrasseur will discuss screening senolytic compounds across models of age-associated decline and advancing their candidacy as interventions. Dr. Justice will detail a framework for biomarker selection in geroscience trials, focusing on a trial of metformin as an example. Dr. Sanders will illustrate how observational data can inform phenotype use in clinical trials. Dr. Levine will explain translating omics data for use in geroscience trials, focusing on epigenomics. We expect additional discussion to hasten development of well-designed geroscience trials.



2016 ◽  
Vol 119 (3) ◽  
pp. 239-248 ◽  
Author(s):  
K.V. Truxal ◽  
H. Fu ◽  
D.M. McCarty ◽  
K.A. McNally ◽  
K.L. Kunkler ◽  
...  


Blood ◽  
2009 ◽  
Vol 114 (13) ◽  
pp. 2575-2580 ◽  
Author(s):  
Mikkael A. Sekeres ◽  
David P. Steensma

Abstract The recent approval of 3 drugs for the treatment of myelodysplastic syndromes (MDSs) has resulted in a revolution in therapeutic options that was absent a decade ago. At the same time, the changing MDS environment is raising new challenges in clinical trial design and defining new indications for MDS drugs. Many current trials still rely on IPSS-based enrollment criteria, despite the well-recognized limitations of the IPSS. Clinical trialists designing studies struggle with several important trial design challenges, including which patients constitute the “previously treated” and “relapsed/refractory” MDS populations, and how specifically to define disease “progression.” This article considers some of these issues as they relate to study design, including how to identify certain MDS populations and define disease progression.





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