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Featured researches published by Bradley T. Wyman.


Arthritis & Rheumatism | 2013

Tofacitinib (CP‐690,550) in patients with rheumatoid arthritis receiving methotrexate: Twelve‐month data from a twenty‐four–month phase III randomized radiographic study

Désirée van der Heijde; Yoshiya Tanaka; R. Fleischmann; Edward C. Keystone; Joel M. Kremer; Cristiano A. F. Zerbini; Mario H. Cardiel; Stanley B. Cohen; Peter Nash; Yeong-Wook Song; Dana Tegzová; Bradley T. Wyman; David Gruben; B. Benda; Gene V. Wallenstein; Sriram Krishnaswami; Samuel H. Zwillich; J. Bradley; Carol A. Connell

OBJECTIVE The purpose of this 24-month phase III study was to examine structural preservation with tofacitinib in patients with rheumatoid arthritis (RA) with an inadequate response to methotrexate (MTX). Data from a planned 12-month interim analysis are reported. METHODS In this double-blind, parallel-group, placebo-controlled study, patients receiving background MTX were randomized 4:4:1:1 to tofacitinib at 5 mg twice daily, tofacitinib at 10 mg twice daily, placebo to tofacitinib at 5 mg twice daily, and placebo to tofacitinib at 10 mg twice daily. At month 3, nonresponder placebo-treated patients were advanced in a blinded manner to receive tofacitinib as indicated above; remaining placebo-treated patients were advanced at 6 months. Four primary efficacy end points were all analyzed in a step-down procedure. RESULTS At month 6, response rates according to the American College of Rheumatology 20% improvement criteria for tofacitinib at 5 mg and 10 mg twice daily were higher than those for placebo (51.5% and 61.8%, respectively, versus 25.3%; both P < 0.0001). At month 6, least squares mean (LSM) changes in total modified Sharp/van der Heijde score for tofacitinib at 5 mg and 10 mg twice daily were 0.12 and 0.06, respectively, versus 0.47 for placebo (P = 0.0792 and P ≤ 0.05, respectively). At month 3, LSM changes in the Health Assessment Questionnaire disability index score for tofacitinib at 5 mg and 10 mg twice daily were -0.40 (significance not declared due to step-down procedure) and -0.54 (P < 0.0001), respectively, versus -0.15 for placebo. At month 6, rates of remission (defined as a value <2.6 for the 4-variable Disease Activity Score in 28 joints using the erythrocyte sedimentation rate) for tofacitinib at 5 mg and 10 mg twice daily were 7.2% (significance not declared due to step-down procedure) and 16.0% (P < 0.0001), respectively, versus 1.6% for placebo. The safety profile was consistent with findings in previous studies. CONCLUSION Data from this 12-month interim analysis demonstrate that tofacitinib inhibits progression of structural damage and improves disease activity in patients with RA who are receiving MTX.


Annals of the Rheumatic Diseases | 2009

One year change of knee cartilage morphology in the first release of participants from the Osteoarthritis Initiative progression subcohort: association with sex, body mass index, symptoms and radiographic osteoarthritis status

F. Eckstein; S. Maschek; W. Wirth; M. Hudelmaier; Wolfgang Hitzl; Bradley T. Wyman; Michael C. Nevitt; M-P. Hellio Le Graverand

Objective: The Osteoarthritis Initiative (OAI) is a multicentre study targeted at identifying biomarkers for evaluating the progression and risk factors of symptomatic knee OA. Here cartilage loss using 3 Tesla (3 T) MRI is analysed over 1 year in a subset of the OAI, together with its association with various risk factors. Methods: An age- and gender-stratified subsample of the OAI progression subcohort (79 women and 77 men, mean (SD) age 60.9 (9.9) years, body mass index (BMI) 30.3 (4.7)) with both frequent symptoms and radiographic OA in at least one knee was studied. Coronal FLASHwe (fast low angle shot with water excitation) MRIs of the right knee were acquired at 3 T. Seven readers segmented tibial and femoral cartilages blinded to order of acquisition. Segmentations were quality controlled by one expert. Results: The reduction in mean cartilage thickness (ThC) was greater (p = 0.004) in the medial than in the lateral compartment, greater (p = 0.001) in the medial femur (−1.9%) than in the medial tibia (−0.5%) and greater (p = 0.011) in the lateral tibia (−0.7%) than in the lateral femur (0.1%). Multifactorial analysis of variance did not reveal significant differences in the rate of change in ThC by sex, BMI, symptoms and radiographic knee OA status. Knees with Kellgren–Lawrence grade 2 or 3 and with a BMI >30 tended to display greater changes. Conclusions: In this sample of the OAI progression subcohort, the greatest, but overall very modest, rate of cartilage loss was observed in the weight-bearing medial femoral condyle. Knees with radiographic OA in obese participants showed trends towards higher rates of change than those of other participants, but these trends did not reach statistical significance.


Osteoarthritis and Cartilage | 2009

Regional analysis of femorotibial cartilage loss in a subsample from the Osteoarthritis Initiative progression subcohort

W. Wirth; M.-P. Hellio Le Graverand; Bradley T. Wyman; S. Maschek; M. Hudelmaier; Wolfgang Hitzl; Michael C. Nevitt; F. Eckstein

OBJECTIVE The Osteoarthritis Initiative (OAI) is aimed at validating (imaging) biomarkers for monitoring progression of knee OA. Here we analyze regional femorotibial (FT) cartilage thickness changes over 1 year using 3 Tesla MRI. Specifically, we tested whether changes in central subregions exceed those in the total cartilage plates. METHODS The right knees of a subsample of the OAI progression subcohort (n=156, age 60.9+/-9.9 years) were studied. Fifty-four participants had definite radiographic osteoarthritis (OA) (KLG 2 or 3) and a BMI>30. Mean and minimal cartilage thickness were determined in subregions of the medial/lateral tibia (MT/LT), and of the medial/lateral weight-bearing femoral condyle (cMF/cLF), after paired (baseline, follow up) segmentation of coronal FLASHwe images with blinding to the order of acquisition. RESULTS The central aspect of cMF displayed a 5.8%/2.8% change in mean thickness in the group of 54/156 participants, respectively, with a standardized response mean (SRM) of -0.47/-0.31, whereas cartilage loss in the total cMF was 4.1%/1.9% (SRM -0.49/-0.30). In the central MT, the rate of change was -1.6%/-0.9% and the SRM -0.29/-0.20, whereas for the entire MT the rate was -1.0%/-0.5% and the SRM -0.21/-0.12. Minimal thickness displayed greater rates of change, but lower SRMs than mean thickness. CONCLUSIONS This study shows that the rate of cartilage loss is greater in central subregions than in entire FT cartilage plates. The sensitivity to change in central subregions was higher than for the total cartilage plate in the MT and was similar to the total plate in the medial weight-bearing femur.


Annals of the Rheumatic Diseases | 2008

Precision of 3.0 Tesla quantitative magnetic resonance imaging of cartilage morphology in a multicentre clinical trial

F. Eckstein; R. Buck; Deborah Burstein; Hal Cecil Charles; J. Crim; M. Hudelmaier; David J. Hunter; G. Hutchins; Christopher G. Jackson; V. Byers Kraus; Nancy E. Lane; Thomas M. Link; L. S. Majumdar; S.A. Mazzuca; Pottumarthi V. Prasad; Thomas J. Schnitzer; Mihra S. Taljanovic; A. Vaz; Bradley T. Wyman; M.-P. Hellio Le Graverand

Objective: Quantitative MRI (qMRI) of cartilage morphology is a promising tool for disease-modifying osteoarthritis drug (DMOAD) development. Recent studies at single sites have indicated that measurements at 3.0 Tesla (T) are more reproducible (precise) than those at 1.5 T. Precision errors and stability in multicentre studies with imaging equipment from various vendors have, however, not yet been evaluated. Methods: A total of 158 female participants (97 Kellgren and Lawrence grade (KLG) 0, 31 KLG 2 and 30 KLG 3) were imaged at 7 clinical centres using Siemens Magnetom Trio and GE Signa Excite magnets. Double oblique coronal acquisitions were obtained at baseline and at 3 months, using water excitation spoiled gradient echo sequences (1.0×0.31×0.31 mm3 resolution). Segmentation of femorotibial cartilage morphology was performed using proprietary software (Chondrometrics GmbH, Ainring, Germany). Results: The precision error (root mean square coefficient of variation (RMS CV)%) for cartilage thickness/volume measurements ranged from 2.1%/2.4% (medial tibia) to 2.9%/3.3% (lateral weight-bearing femoral condyle) across all participants. No significant differences in precision errors were observed between KLGs, imaging sites, or scanner manufacturers/types. Mean differences between baseline and 3 months ranged from <0.1% (non-significant) in the medial to 0.94% (p<0.01) in the lateral femorotibial compartment, and were 0.33% (p<0.02) for the total femorotibial subchondral bone area. Conclusions: qMRI performed at 3.0 T provides highly reproducible measurements of cartilage morphology in multicentre clinical trials with equipment from different vendors. The technology thus appears sufficiently robust to be recommended for large-scale multicentre trials.


Annals of the Rheumatic Diseases | 2008

Head-to-head comparison of the Lyon Schuss and fixed flexion radiographic techniques. Long-term reproducibility in normal knees and sensitivity to change in osteoarthritic knees

Marie Pierre Hellio Le Graverand; E. Vignon; Kenneth D. Brandt; S.A. Mazzuca; Muriel Piperno; R. Buck; Hal Cecil Charles; David J. Hunter; Christopher G. Jackson; V. Byers Kraus; Thomas M. Link; Thomas J. Schnitzer; A. Vaz; Bradley T. Wyman

OBJECTIVE The Lyon Schuss (LS) and fixed flexion (FF) views of the knee are superior to a conventional standing anteroposterior view in evaluating joint space narrowing (JSN) in osteoarthritis (OA). Both position the knee identically but only the LS aligns the medial tibial plateau (MTP) with the x-ray beam fluoroscopically. The present study provides the first head-to-head comparison of the LS and FF views. METHODS At baseline and 12 months, 62 OA and 99 control knees were imaged twice on the same day with LS and FF views. Minimum joint space width (mJSW) was measured by computer and MTP alignment was assessed from the distance between anterior and posterior margins of the MTP (intermargin distance, IMD). Reproducibility of measurements of mJSW and sensitivity to change were evaluated. RESULTS In normal knees, JSW did not vary over 12 months with either view. In OA knees, 12-month mJSN was 0.22 (0.43) mm with the LS view and -0.01 (0.46) mm with the FF view (p = 0.0002 and p = 0.92, respectively). Mean IMD was only half as large in LS as in FF views (0.9 (0.5) mm vs 1.9 (1.2) mm, p<0.0001). CONCLUSIONS LS and FF radiographs offer similar reproducibility in JSW measurement. However, presumably due to its superiority in aligning the MTP, the LS view is much more sensitive to JSN in OA knees.


Annals of the Rheumatic Diseases | 2010

Change in regional cartilage morphology and joint space width in osteoarthritis participants versus healthy controls: a multicentre study using 3.0 Tesla MRI and Lyon–Schuss radiography

Marie-Pierre Hellio Le Graverand; R. Buck; Bradley T. Wyman; E. Vignon; Steven A. Mazzuca; Kenneth D. Brandt; Muriel Piperno; H. Cecil Charles; M. Hudelmaier; David J. Hunter; Christopher G. Jackson; Virginia B. Kraus; Thomas M. Link; Sharmila Majumdar; Pottumarthi V. Prasad; Thomas J. Schnitzer; Austin Vaz; W. Wirth; F. Eckstein

Objective: Cartilage morphology displays sensitivity to change in osteoarthritis (OA) with quantitative MRI (qMRI). However, (sub)regional cartilage thickness change at 3.0 Tesla (T) has not been directly compared with radiographic progression of joint space narrowing in OA participants and non-arthritic controls. Methods: A total of 145 women were imaged at 7 clinical centres: 86 were non-obese and asymptomatic without radiographic OA and 55 were obese with symptomatic and radiographic OA (27 Kellgren–Lawrence grade (KLG)2 and 28 KLG3). Lyon–Schuss (LS) and fixed flexion (FF) radiographs were obtained at baseline, 12 and 24 months, and coronal spoiled gradient echo MRI sequences at 3.0 T at baseline, 6, 12 and 24 months. (Sub)regional, femorotibial cartilage thickness and minimum joint space width (mJSW) in the medial femorotibial compartment were measured and the standardised response means (SRMs) determined. Results: At 6 months, qMRI demonstrated a −3.7% “annualised” change in cartilage thickness (SRM −0.33) in the central medial femorotibial compartment (cMFTC) of KLG3 subjects, but no change in KLG2 subjects. The SRM for mJSW in 12-month LS/FF radiographs of KLG3 participants was −0.68/−0.13 and at 24 months was −0.62/−0.20. The SRM for cMFTC changes measured with qMRI was −0.32 (12 months; −2.0%) and −0.48 (24 months; −2.2%), respectively. Conclusions: qMRI and LS radiography detected significant change in KLG3 participants at high risk of progression, but not in KLG2 participants, and only small changes in controls. At 12 and 24 months, LS displayed greater, and FF less, sensitivity to change in KLG3 participants than qMRI.


Radiology | 2008

Carotid plaque morphology and composition: initial comparison between 1.5- and 3.0-T magnetic field strengths.

Hunter R. Underhill; Vasily L. Yarnykh; Thomas S. Hatsukami; Jinnan Wang; Niranjan Balu; Cecil E. Hayes; Minako Oikawa; Wei Yu; Dongxiang Xu; Baocheng Chu; Bradley T. Wyman; Nayak L. Polissar; Chun Yuan

PURPOSE To prospectively compare the interpretation and quantification of carotid vessel wall morphology and plaque composition at 1.5-T with those at 3.0-T magnetic resonance (MR) imaging. MATERIALS AND METHODS Twenty participants (mean age, 69.8 years [standard deviation] +/- 10.5; 75% men) with 16%-79% carotid stenosis at duplex ultrasonography were imaged with 1.5-T and 3.0-T MR imaging units with bilateral four-element phased-array surface coils. This HIPAA-compliant study was approved by the institutional review board, and all participants gave written informed consent. Protocols designed for similar signal-to-noise ratios across platforms were implemented to acquire axial T1-weighted, T2-weighted, intermediate-weighted, time-of-flight, and contrast material-enhanced T1-weighted images. Lumen area, wall area, total vessel area, wall thickness, and presence or absence and area of plaque components were documented. Continuous variables from different field strengths were compared by using the intraclass correlation coefficient (ICC) and repeated measures analysis. The Cohen kappa was used to evaluate agreement between 1.5 T and 3.0 T on compositional dichotomous variables. RESULTS There was a strong level of agreement between field strengths for all morphologic variables, with ICCs ranging from 0.88 to 0.96. Agreement in the identification of presence or absence of plaque components was very good for calcification (kappa = 0.72), lipid-rich necrotic core (kappa = 0.73), and hemorrhage (kappa = 0.66). However, the visualization of hemorrhage was greater at 1.5 T than at 3.0 T (14.7% vs 7.8%, P < .001). Calcifications measured significantly (P = .03) larger at 3.0 T, while lipid-rich necrotic cores without hemorrhage were similar between field strengths (P = .9). CONCLUSION At higher field strengths, the increased susceptibility of calcification and paramagnetic ferric iron in hemorrhage may alter quantification and/or detection. Nevertheless, imaging criteria at 1.5 T for carotid vessel wall interpretation are applicable at 3.0 T.


Alzheimers & Dementia | 2013

Standardization of analysis sets for reporting results from ADNI MRI data

Bradley T. Wyman; Danielle Harvey; Karen Crawford; Matt A. Bernstein; Owen T. Carmichael; Patricia E. Cole; Paul K. Crane; Charles DeCarli; Nick C. Fox; Jeffrey L. Gunter; Derek L. G. Hill; Ronald J. Killiany; Chahin Pachai; Adam J. Schwarz; Norbert Schuff; Matthew L. Senjem; Joyce Suhy; Paul M. Thompson; Michael W. Weiner; Clifford R. Jack

The Alzheimers Disease Neuroimaging Initiative (ADNI) three‐dimensional T1‐weighted magnetic resonance imaging (MRI) acquisitions provide a rich data set for developing and testing analysis techniques for extracting structural endpoints. To promote greater rigor in analysis and meaningful comparison of different algorithms, the ADNI MRI Core has created standardized analysis sets of data comprising scans that met minimum quality control requirements. We encourage researchers to test and report their techniques against these data. Standard analysis sets of volumetric scans from ADNI‐1 have been created, comprising screening visits, 1‐year completers (subjects who all have screening, 6‐ and 12‐month scans), 2‐year annual completers (screening, 1‐year and 2‐year scans), 2‐year completers (screening, 6‐months, 1‐year, 18‐months [mild cognitive impaired (MCI) only], and 2‐year scans), and complete visits (screening, 6‐month, 1‐year, 18‐month [MCI only], 2‐year, and 3‐year [normal and MCI only] scans). As the ADNI‐GO/ADNI‐2 data become available, updated standard analysis sets will be posted regularly.


NeuroImage | 2012

A computational neurodegenerative disease progression score: Method and results with the Alzheimer's disease neuroimaging initiative cohort

Bruno Jedynak; Andrew Lang; Bo Liu; Elyse Katz; Yanwei Zhang; Bradley T. Wyman; David Raunig; C. Pierre Jedynak; Brian Caffo; Jerry L. Prince

While neurodegenerative diseases are characterized by steady degeneration over relatively long timelines, it is widely believed that the early stages are the most promising for therapeutic intervention, before irreversible neuronal loss occurs. Developing a therapeutic response requires a precise measure of disease progression. However, since the early stages are for the most part asymptomatic, obtaining accurate measures of disease progression is difficult. Longitudinal databases of hundreds of subjects observed during several years with tens of validated biomarkers are becoming available, allowing the use of computational methods. We propose a widely applicable statistical methodology for creating a disease progression score (DPS), using multiple biomarkers, for subjects with a neurodegenerative disease. The proposed methodology was evaluated for Alzheimers disease (AD) using the publicly available AD Neuroimaging Initiative (ADNI) database, yielding an Alzheimers DPS or ADPS score for each subject and each time-point in the database. In addition, a common description of biomarker changes was produced allowing for an ordering of the biomarkers. The Rey Auditory Verbal Learning Test delayed recall was found to be the earliest biomarker to become abnormal. The group of biomarkers comprising the volume of the hippocampus and the protein concentration amyloid beta and Tau were next in the timeline, and these were followed by three cognitive biomarkers. The proposed methodology thus has potential to stage individuals according to their state of disease progression relative to a population and to deduce common behaviors of biomarkers in the disease itself.


Osteoarthritis and Cartilage | 2010

The association of prevalent medial meniscal pathology with cartilage loss in the medial tibiofemoral compartment over a 2-year period.

M.D. Crema; Ali Guermazi; Ling Li; Marcello Henrique Nogueira-Barbosa; M.D. Marra; Frank W. Roemer; F. Eckstein; M.-P. Hellio Le Graverand; Bradley T. Wyman; David J. Hunter

OBJECTIVE To investigate the association of different types of magnetic resonance imaging (MRI)-detected medial meniscal pathology with subregional cartilage loss in the medial tibiofemoral compartment. METHODS A total of 152 women aged >or=40 years, with and without knee osteoarthritis (OA) were included in a longitudinal 24-month observational study. Spoiled gradient recalled acquisitions at steady state (SPGR) and T2-weighted fat-suppressed MRI sequences were acquired. Medial meniscal status of the anterior horn (AH), body, and posterior horn (PH) was graded at baseline: 0 (normal), 1 (intrasubstance meniscal signal changes), 2 (single tears), and 3 (complex tears/maceration). Cartilage segmentation was performed at baseline and 24-month follow-up in various tibiofemoral subregions using computation software. Multiple linear regression models were applied for the analysis with cartilage loss as the outcome. In a first model, the results were adjusted for age and body mass index (BMI). In a second model, the results were adjusted for age, BMI and medial meniscal extrusion. RESULTS After adjusting for age, BMI, and medial meniscal extrusion, cartilage loss in the total medial tibia (MT) (0.04 mm, P=0.04) and the external medial tibia (eMT) (0.068 mm, P=0.04) increased significantly for compartments with grade 3 lesions. Cartilage loss in the total central medial femoral condyle (cMF) (0.071 mm, P=0.03) also increased significantly for compartments with grade 2 lesions. Cartilage loss at the eMT was significantly related to tears of the PH (0.074 mm; P=0.03). Cartilage loss was not significantly increased for compartments with grade 1 lesions. CONCLUSION The protective function of the meniscus appears to be preserved in the presence of intrasubstance meniscal signal changes. Prevalent single tears and meniscal maceration were found to be associated with increased cartilage loss in the same compartment, especially at the PH.

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Thomas M. Link

University of California

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David J. Hunter

Royal North Shore Hospital

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Enchi Liu

Janssen Pharmaceutica

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