6 results on '"Hannan KL"'
Search Results
2. Assessment of North American Clinical Research Site Performance During the Start-up of Large Cardiovascular Clinical Trials.
- Author
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Goyal A, Schibler T, Alhanti B, Hannan KL, Granger CB, Blazing MA, Lopes RD, Alexander JH, Peterson ED, Rao SV, Green JB, Roe MT, Rorick T, Berdan LG, Reist C, Mahaffey KW, Harrington RA, Califf RM, Patel MR, Hernandez AF, and Jones WS
- Subjects
- Cardiovascular Diseases, Cohort Studies, Humans, North America, Reference Standards, Academies and Institutes standards, Benchmarking methods, Randomized Controlled Trials as Topic standards, Time Factors
- Abstract
Importance: Randomized clinical trials (RCTs) are critical in advancing patient care, yet conducting such large-scale trials requires tremendous resources and coordination. Clinical site start-up performance metrics can provide insight into opportunities for improved trial efficiency but have not been well described., Objective: To measure the start-up time needed to reach prespecified milestones across sites in large cardiovascular RCTs in North America and to evaluate how these metrics vary by time and type of regulatory review process., Design, Setting, and Participants: This cohort study evaluated cardiovascular RCTs conducted from July 13, 2004, to February 1, 2017. The RCTs were coordinated by a single academic research organization, the Duke Clinical Research Institute. Nine consecutive trials with completed enrollment and publication of results in their target journal were studied. Data were analyzed from December 4, 2019, to January 11, 2021., Exposures: Year of trial enrollment initiation (2004-2007 vs 2008-2012) and use of a central vs local institutional review board (IRB)., Main Outcomes and Measures: The primary outcome was the median start-up time (from study protocol delivery to first participant enrollment) as compared by trial year and type of IRB used. The median start-up time for the top 10% of sites was also reported. Secondary outcomes included time to site regulatory approval, time to contract execution, and time to site activation., Results: For the 9 RCTs included, the median site start-up time shortened only slightly over time from 267 days (interquartile range [IQR], 185-358 days) for 2004-2007 trials to 237 days (IQR, 162-343 days) for 2008-2012 trials (overall median, 255 days [IQR, 177-350 days]; P < .001). For the top 10% of sites, median start-up time was 107 days (IQR, 95-121 days) for 2004-2007 trials vs 104 days (IQR, 84-118 days) for 2008-2012 trials (overall median, 106 days [IQR, 90-120 days]; P = .04). The median start-up time was shorter among sites using a central IRB (199 days [IQR, 140-292 days]) than those using a local IRB (287 days [IQR, 205-390 days]; P < .001)., Conclusions and Relevance: This cohort study of North American research sites in large cardiovascular RCTs found a duration of nearly 9 months from the time of study protocol delivery to the first participant enrollment; this metric was only slightly shortened during the study period but was reduced to less than 4 months for top-performing sites. These findings suggest that the use of central IRBs has the potential to improve RCT efficiency.
- Published
- 2021
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3. End of study transition from study drug to open-label vitamin K antagonist therapy: the ROCKET AF experience.
- Author
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Mahaffey KW, Hellkamp AS, Patel MR, Hannan KL, Schwabe K, Nessel CC, Berkowitz SD, Halperin JL, Hankey GJ, Becker RC, Piccini JP, Breithardt G, Hacke W, Singer DE, Califf RM, and Fox KA
- Subjects
- Aged, Aged, 80 and over, Anticoagulants adverse effects, Atrial Fibrillation complications, Atrial Fibrillation diagnosis, Clinical Protocols, Double-Blind Method, Drug Administration Schedule, Embolism etiology, Factor Xa metabolism, Factor Xa Inhibitors, Female, Humans, International Normalized Ratio, Male, Middle Aged, Morpholines adverse effects, Proportional Hazards Models, Research Design, Risk Factors, Rivaroxaban, Stroke etiology, Thiophenes adverse effects, Time Factors, Treatment Outcome, Vitamin K blood, Warfarin adverse effects, Anticoagulants administration & dosage, Atrial Fibrillation drug therapy, Blood Coagulation drug effects, Continuity of Patient Care, Drug Substitution, Embolism prevention & control, Morpholines administration & dosage, Stroke prevention & control, Thiophenes administration & dosage, Vitamin K antagonists & inhibitors, Warfarin administration & dosage
- Abstract
Background: To evaluate the previously reported excess of thromboembolic events during the 30 days after the end of study (EOS) visit when participants transitioned from blinded therapy to open-label vitamin K antagonist., Methods and Results: At the EOS visit, open-label vitamin K antagonist was recommended, and the international normalized ratio (INR) was not to be measured until 3 days later to preserve blinding. We analyzed transition strategies, clinical outcomes, and INR values. Event rates are per 100 patient-years. A total of 9248 (65%) participants were taking study drug at EOS, and, between days 3 and 30, an excess of stroke and systemic embolic events were observed in participants assigned to rivaroxaban (rivaroxaban 22 events, event rate 6.42; warfarin 6 events, event rate 1.73; hazard ratio, 3.72; 95% confidence interval, 1.51-9.16; P=0.0044). No INR values were reported for ≈5% of participants transitioned to warfarin. By 30 days after EOS, 83% of the warfarin group and 52% of the rivaroxaban group had ≥1 therapeutic INR value. Median time to first therapeutic INR was 3 days in the warfarin group and 13 days in the rivaroxaban group., Conclusions: The excess of events at EOS was likely because of a period of inadequate anticoagulation in rivaroxaban participants switched to vitamin K antagonist therapy. If transition from rivaroxaban to vitamin K antagonist is needed, timely monitoring and careful dosing should be used to ensure consistent and adequate anticoagulation.
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- 2013
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4. Caudate nucleus volume in individuals at ultra-high risk of psychosis: a cross-sectional magnetic resonance imaging study.
- Author
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Hannan KL, Wood SJ, Yung AR, Velakoulis D, Phillips LJ, Soulsby B, Berger G, McGorry PD, and Pantelis C
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- Adolescent, Adult, Cognition Disorders etiology, Cognition Disorders pathology, Cross-Sectional Studies, Female, Humans, Lateral Ventricles pathology, Magnetic Resonance Imaging methods, Male, Psychiatric Status Rating Scales, Psychological Tests, Psychotic Disorders complications, Risk, Verbal Behavior physiology, Young Adult, Caudate Nucleus pathology, Psychotic Disorders genetics, Psychotic Disorders pathology
- Abstract
The aim of the present study was to investigate whether volumetric abnormalities of the caudate nuclei predate the onset of psychotic illness. Caudate nuclei volume (CNVs), excluding the tail, were measured using region-of-interest (ROI) tracing of magnetic resonance imaging (MRI) scans acquired on a 1.5T scanner. Subjects included 39 individuals deemed at ultra-high risk of psychosis who converted to psychosis (UHR-P) after initial MRI scanning; 39 matched individuals at ultra-high risk who did not convert to psychosis (UHR-NP); and 39 matched healthy controls. All subjects were neuroleptic-naïve. After adjusting CNVs for intracranial volume (ICV), univariate analyses of variance and repeated measures analyses of variance were undertaken to examine the relationship of CNVs to psychosis transition and to family history of psychosis. Pearson's correlations were used to investigate the relationship of psychopathological scores to CNVs. CNVs did not differ significantly between UHR individuals and healthy controls, and there was no significant difference between converters and non-converters to psychosis. In the UHR group, presence of family history of psychosis was not related to CNVs. There was no correlation between CNVs and either positive or negative symptoms of schizophrenia. Significant associations were found between larger CNV and increased errors on a spatial working memory task but better verbal fluency performance. These data suggest that the caudate is macroscopically normal prior to illness onset, while the relationship to tasks of executive function may implicate the caudate together with its connections to prefrontal regions. Future research should examine changes longitudinally together with analysis of shape to assess subregions of the caudate that connect with prefrontal cortex.
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- 2010
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5. Combination reperfusion therapy with eptifibatide and reduced-dose tenecteplase for ST-elevation myocardial infarction: results of the integrilin and tenecteplase in acute myocardial infarction (INTEGRITI) Phase II Angiographic Trial.
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Giugliano RP, Roe MT, Harrington RA, Gibson CM, Zeymer U, Van de Werf F, Baran KW, Hobbach HP, Woodlief LH, Hannan KL, Greenberg S, Miller J, Kitt MM, Strony J, McCabe CH, Braunwald E, and Califf RM
- Subjects
- Adult, Aged, Blood Flow Velocity drug effects, Coronary Angiography, Coronary Circulation drug effects, Drug Administration Schedule, Drug Therapy, Combination, Eptifibatide, Female, Humans, Injections, Intravenous, Male, Middle Aged, Myocardial Infarction metabolism, Myocardial Infarction physiopathology, Peptides administration & dosage, Platelet Glycoprotein GPIIb-IIIa Complex drug effects, Tenecteplase, Tissue Plasminogen Activator administration & dosage, Treatment Outcome, Fibrinolytic Agents therapeutic use, Heart Conduction System physiopathology, Myocardial Infarction drug therapy, Peptides therapeutic use, Platelet Aggregation Inhibitors therapeutic use, Platelet Glycoprotein GPIIb-IIIa Complex metabolism, Tissue Plasminogen Activator therapeutic use
- Abstract
Objectives: The goal of this study was to evaluate combinations of eptifibatide with reduced-dose tenecteplase (TNK) in ST-elevation myocardial infarction (STEMI)., Background: Glycoprotein IIb/IIIa inhibitors enhance thrombolysis. The role of combination therapy in clinical practice remains to be established., Methods: Patients (n = 438) with STEMI <6 h were enrolled. In dose-finding, 189 patients were randomized to different combinations of double-bolus eptifibatide and reduced-dose TNK. In dose-confirmation, 249 patients were randomized 1:1 to eptifibatide 180 microg/kg bolus, 2 microg/kg/min infusion, and 180 microg/kg bolus 10 min later (180/2/180) plus half-dose TNK (0.27 mg/kg) or standard-dose (0.53 mg/kg) TNK monotherapy. All patients received aspirin and unfractionated heparin (60 U/kg bolus; infusion 7 U/kg/h [combination], 12 U/kg/h [monotherapy]). The primary end point was Thrombolysis In Myocardial Infarction (TIMI) grade 3 epicardial flow at 60 min., Results: In dose-finding, TIMI grade 3 flow rates were similar across groups (64% to 68%). Arterial patency was highest for eptifibatide 180/2/180 plus half-dose TNK (96%, p = 0.02 vs. eptifibatide 180/2/90 plus half-dose TNK). In dose-confirmation, this combination, compared with TNK monotherapy, tended to achieve more TIMI 3 flow (59% vs. 49%, p = 0.15), arterial patency (85% vs. 77%, p = 0.17), and ST-segment resolution (median 71% vs. 61%, p = 0.08) but was associated with more major hemorrhage (7.6% vs. 2.5%, p = 0.14) and transfusions (13.4% vs. 4.2%, p = 0.02). Intracranial hemorrhage occurred in 1.0%, 0.6%, and 1.7% of patients treated with any combination, eptifibatide 180/2/180 and half-dose TNK, and TNK monotherapy, respectively., Conclusions: Double-bolus eptifibatide (180/2/180) plus half-dose TNK tended to improve angiographic flow and ST-segment resolution compared with TNK monotherapy but was associated with more transfusions and non-cerebral bleeding. Further study is needed before this combination can be recommended for general use.
- Published
- 2003
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6. Activation of the coagulation system in Gulf War Illness: a potential pathophysiologic link with chronic fatigue syndrome. A laboratory approach to diagnosis.
- Author
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Hannan KL, Berg DE, Baumzweiger W, Harrison HH, Berg LH, Ramirez R, and Nichols D
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- Adult, Biomarkers blood, Blood Flow Velocity, Case-Control Studies, Clinical Laboratory Techniques, Diagnosis, Differential, Fatigue Syndrome, Chronic blood, Fatigue Syndrome, Chronic diagnosis, Fibromyalgia blood, Fibromyalgia diagnosis, Humans, Immune System, Persian Gulf Syndrome etiology, Thrombophilia blood, Thrombophilia etiology, Veterans, Blood Coagulation, Persian Gulf Syndrome blood, Persian Gulf Syndrome diagnosis
- Abstract
Most symptoms of Gulf War Illness (GWI) are similar to Chronic Fatigue Syndrome (CFS) and/or Fibromyalgia (FM). We investigated whether these symptoms are associated with an activated coagulation system as has been reported in some cases of CFS/FM. The coagulation assays include activation markers of the cascade, platelet activation and hereditary risk factors. Our findings show activation of the coagulation system in GWI. This evidence of a hypercoagulable state suggests that symptoms may be due to poor blood flow and, therefore, a basis for the potential utility of anticoagulant therapy.
- Published
- 2000
- Full Text
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