Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
Immunother Adv ; 3(1): ltad026, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38020310

RESUMO

Immunotherapy treatment strategies have proven effective in a limited portion of patients, where identifying responders from non-responders to treatment remains a challenge. While some indications can be drawn from invasive biopsies, we need more accessible methods for predicting response and better correlates of response prior to starting therapy. Recent work has identified differences in immune composition at baseline in peripheral blood from melanoma patients responding to PD-1 blockade treatment. Through flow cytometric analysis of T cell receptors, phenotypical features of CD8+ and CD4+ T cells and Tregs could allow for the stratification of treatment response. Analysing T cells within peripheral blood could potentially allow for the stratification of PD-1 treatment response prior to therapy in different cancer settings.

2.
Stroke ; 53(1): 29-33, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34847709

RESUMO

BACKGROUND AND PURPOSE: Cerebral small vessel disease-a major cause of stroke and dementia-is associated with cerebrovascular dysfunction. We investigated whether short-term isosorbide mononitrate (ISMN) and cilostazol, alone or in combination, improved magnetic resonance imaging-measured cerebrovascular function in patients with lacunar ischemic stroke. METHODS: Participants were randomized to ISMN alone, cilostazol alone, both ISMN and cilostazol, or no medication. Participants underwent structural, cerebrovascular reactivity (to 6% carbon dioxide) and phase-contrast pulsatility magnetic resonance imaging at baseline and after 8 weeks of medication. RESULTS: Of 27 participants (mean age, 68±7.7; 44% female), 22 completed cerebrovascular reactivity and pulsatility imaging with complete datasets. White matter cerebrovascular reactivity increased in the ISMN (ß=0.021%/mm Hg [95% CI, 0.003-0.040]) and cilostazol (ß=0.035%/mm Hg [95% CI, 0.014-0.056]) monotherapy groups and in those taking any versus no medication (ß=0.021%/mm Hg [95% CI, 0.005-0.037]). CONCLUSIONS: While limited by small sample size, we demonstrate that measuring cerebrovascular function with magnetic resonance imaging is feasible in clinical trials and that ISMN and cilostazol may improve cerebrovascular function. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02481323. URL: www.isrctn.com; Unique identifier: ISRCTN12580546. URL: www.clinicaltrialsregister.eu; Unique identifier: EudraCT 2015-001953-33.


Assuntos
Doenças de Pequenos Vasos Cerebrais/tratamento farmacológico , Cilostazol/uso terapêutico , Hemodinâmica/efeitos dos fármacos , Dinitrato de Isossorbida/análogos & derivados , Lipoproteínas/uso terapêutico , Vasodilatadores/uso terapêutico , Idoso , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/fisiopatologia , Cilostazol/farmacologia , Feminino , Hemodinâmica/fisiologia , Humanos , Dinitrato de Isossorbida/farmacologia , Dinitrato de Isossorbida/uso terapêutico , Lipoproteínas/farmacologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Vasodilatadores/farmacologia
3.
Stroke ; 52(8): 2629-2636, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34000834

RESUMO

BACKGROUND AND PURPOSE: The computed tomography angiography or contrast-enhanced computed tomography based spot sign has been proposed as a biomarker for identifying on-going hematoma expansion in patients with acute intracerebral hemorrhage. We investigated, if spot-sign positive participants benefit more from tranexamic acid versus placebo as compared to spot-sign negative participants. METHODS: TICH-2 trial (Tranexamic Acid for Hyperacute Primary Intracerebral Haemorrhage) was a randomized, placebo-controlled clinical trial recruiting acutely hospitalized participants with intracerebral hemorrhage within 8 hours after symptom onset. Local investigators randomized participants to 2 grams of intravenous tranexamic acid or matching placebo (1:1). All participants underwent computed tomography scan on admission and on day 2 (24±12 hours) after randomization. In this sub group analysis, we included all participants from the main trial population with imaging allowing adjudication of spot sign status. RESULTS: Of the 2325 TICH-2 participants, 254 (10.9%) had imaging allowing for spot-sign adjudication. Of these participants, 64 (25.2%) were spot-sign positive. Median (interquartile range) time from symptom onset to administration of the intervention was 225.0 (169.0 to 310.0) minutes. The adjusted percent difference in absolute day-2 hematoma volume between participants allocated to tranexamic versus placebo was 3.7% (95% CI, -12.8% to 23.4%) for spot-sign positive and 1.7% (95% CI, -8.4% to 12.8%) for spot-sign negative participants (Pheterogenity=0.85). No difference was observed in significant hematoma progression (dichotomous composite outcome) between participants allocated to tranexamic versus placebo among spot-sign positive (odds ratio, 0.85 [95% CI, 0.29 to 2.46]) and negative (odds ratio, 0.77 [95% CI, 0.41 to 1.45]) participants (Pheterogenity=0.88). CONCLUSIONS: Data from the TICH-2 trial do not support that admission spot sign status modifies the treatment effect of tranexamic acid versus placebo in patients with acute intracerebral hemorrhage. The results might have been affected by low statistical power as well as treatment delay. Registration: URL: http://www.controlled-trials.com; Unique identifier: ISRCTN93732214.


Assuntos
Antifibrinolíticos/uso terapêutico , Hemorragia Cerebral/tratamento farmacológico , Hematoma/tratamento farmacológico , Ácido Tranexâmico/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Angiografia Cerebral , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/fisiopatologia , Angiografia por Tomografia Computadorizada , Progressão da Doença , Feminino , Hematoma/diagnóstico por imagem , Hematoma/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Resultado do Tratamento
4.
Cell Rep Med ; 2(12): 100457, 2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-35028604

RESUMO

Second generation (2G) chimeric antigen receptors (CARs) contain a CD28 or 41BB co-stimulatory endodomain and elicit remarkable efficacy in hematological malignancies. Third generation (3G) CARs extend this linear blueprint by fusing both co-stimulatory units in series. However, clinical impact has been muted despite compelling evidence that co-signaling by CD28 and 41BB can powerfully amplify natural immune responses. We postulate that effective dual co-stimulation requires juxta-membrane positioning of endodomain components within separate synthetic receptors. Consequently, we designed parallel (p)CARs in which a 2G (CD28+CD3ζ) CAR is co-expressed with a 41BB-containing chimeric co-stimulatory receptor. We demonstrate that the pCAR platform optimally harnesses synergistic and tumor-dependent co-stimulation to resist T cell exhaustion and senescence, sustaining proliferation, cytokine release, cytokine signaling, and metabolic fitness upon repeated stimulation. When engineered using targeting moieties of diverse composition, affinity, and specificity, pCAR T cells consistently elicit superior anti-tumor activity compared with T cells that express traditional linear CARs.


Assuntos
Antígenos CD28/metabolismo , Membrana Celular/metabolismo , Receptores de Antígenos Quiméricos/metabolismo , Transdução de Sinais , Linfócitos T/imunologia , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Animais , Antígenos de Neoplasias/metabolismo , Linhagem Celular Tumoral , Humanos , Integrinas/metabolismo , Linfoma/imunologia , Camundongos Endogâmicos NOD , Camundongos SCID , Mucina-1/metabolismo , Multimerização Proteica , Receptores de Fator Estimulador de Colônias/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Metabolites ; 10(11)2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33202938

RESUMO

Upon activation T cells engage glucose metabolism to fuel the costly effector functions needed for a robust immune response. Consequently, the availability of glucose can impact on T cell function. The glucose concentrations used in conventional culture media and common metabolic assays are often artificially high, representing hyperglycaemic levels rarely present in vivo. We show here that reducing glucose concentration to physiological levels in culture differentially impacted on virus-specific compared to generically activated human CD8 T cell responses. In virus-specific T cells, limiting glucose availability significantly reduced the frequency of effector-cytokine producing T cells, but promoted the upregulation of CD69 and CD103 associated with an increased capacity for tissue retention. In contrast the functionality of generically activated T cells was largely unaffected and these showed reduced differentiation towards a residency phenotype. Furthermore, T cells being cultured at physiological glucose concentrations were more susceptible to viral infection. This setting resulted in significantly improved lentiviral transduction rates of primary cells. Our data suggest that CD8 T cells are exquisitely adapted to their niche and provide a reminder of the need to better mimic physiological conditions to study the complex nature of the human CD8 T cell immune response.

6.
Front Neurol ; 10: 723, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31333572

RESUMO

Background: Cilostazol and isosorbide mononitrate (ISMN) are candidate treatments for cerebral small vessel disease and lacunar ischaemic stroke. As both drugs may influence hemoglobin and platelet count, and hemodynamics, we sought to assess their effects in the lacunar intervention-1 (LACI-1) trial. Methods: Fifty-seven lacunar ischaemic stroke patients were randomized to immediate ISMN, cilostazol, or their combination for 9 weeks in addition to guideline stroke prevention. A fourth group received both drugs with a delayed start. Full blood count, platelet function, peripheral blood pressure (BP), heart rate and central hemodynamics (Augmentation index, Buckberg index) were measured at baseline, and weeks 3 and 8. Differences were assessed by multiple linear regression adjusted for baseline and key prognostic variables. Registration ISRCTN 12580546. Results: At week 8, platelet count was higher with cilostazol vs. no cilostazol (mean difference, MD 35.73, 95% confidence intervals, 95% CI 2.81-68.66, p = 0.033), but no significant differences were noted for hemoglobin levels or platelet function. At week 8, BP did not differ between the treatment groups, whilst heart rate was higher in those taking cilostazol vs. no cilostazol (MD 6.42, 95% CI 1.17-11.68, p = 0.017). Buckberg index (subendocardial perfusion) was lower in those randomized to cilostazol vs. no cilostazol and in those randomized to both drugs vs. either drug. Whilst ISMN significantly increased unadjusted augmentation index (arterial stiffness, MD 21.19, 95% CI 9.08-33.31, p = 0.001), in isolation both drugs non-significantly reduced augmentation index adjusted for heart rate. Conclusions: Cilostazol increased heart rate and platelet count, and reduced Buckberg index, whilst both drugs may individually reduce arterial stiffness adjusted for heart rate. Neither drug had clinically significant effects on hemoglobin or platelet function over 8 weeks. Further assessment of the safety and efficacy of these medications following lacunar ischaemic stroke is warranted.

7.
EClinicalMedicine ; 11: 34-43, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31317131

RESUMO

BACKGROUND: Lacunar stroke, a frequent clinical manifestation of small vessel disease (SVD), differs pathologically from other ischaemic stroke subtypes and has no specific long-term secondary prevention. Licenced drugs, isosorbide mononitrate (ISMN) and cilostazol, have relevant actions to prevent SVD progression. METHODS: We recruited independent patients with clinically confirmed lacunar ischaemic stroke without cognitive impairment to a prospective randomised clinical trial, LACunar Intervention-1 (LACI-1). We randomised patients using a central web-based system, 1:1:1:1 with minimisation, to masked ISMN 25 mg bd, cilostazol 100 mg bd, both ISMN and cilostazol started immediately, or both with start delayed. We escalated doses to target over two weeks, sustained for eight weeks. Primary outcome was the proportion achieving target dose. Secondary outcomes included symptoms, safety (haemorrhage, recurrent vascular events), cognition, haematology, vascular function, and neuroimaging. LACI-1 was powered (80%, alpha 0.05) to detect 35% (90% versus 55%) difference between the proportion reaching target dose on one versus both drugs at 55 patients. Registration ISRCTN12580546. FINDINGS: LACI-1 enrolled 57 participants between March 2016 and August 2017: 18 (32%) females, mean age 66 (SD 11, range 40-85) years, onset-randomisation 203 (range 6-920) days. Most achieved full (64%) or over half (87%) dose, with no difference between cilostazol vs ISMN, single vs dual drugs. Headache and palpitations increased initially then declined similarly with dual versus single drugs. There was no between-group difference in BP, pulse-wave velocity, haemoglobin or platelet function, but pulse rate was higher (mean difference, MD, 6.4, 95%CI 1.2-11.7, p = 0.02), platelet count higher (MD 35.7, 95%CI 2.8, 68.7, p = 0.03) and white matter hyperintensities reduced more (Chi-square p = 0.007) with cilostazol versus no cilostazol. INTERPRETATION: Cilostazol and ISMN are well tolerated when the dose is escalated, without safety concerns, in patients with lacunar stroke. Larger trials with longer term follow-up are justified. FUNDING: Alzheimer's Society (AS-PG-14-033).

8.
Health Technol Assess ; 23(35): 1-48, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31322116

RESUMO

BACKGROUND: Tranexamic acid reduces death due to bleeding after trauma and postpartum haemorrhage. OBJECTIVE: The aim of the study was to assess if tranexamic acid is safe, reduces haematoma expansion and improves outcomes in adults with spontaneous intracerebral haemorrhage (ICH). DESIGN: The TICH-2 (Tranexamic acid for hyperacute primary IntraCerebral Haemorrhage) study was a pragmatic, Phase III, prospective, double-blind, randomised placebo-controlled trial. SETTING: Acute stroke services at 124 hospitals in 12 countries (Denmark, Georgia, Hungary, Ireland, Italy, Malaysia, Poland, Spain, Sweden, Switzerland, Turkey and the UK). PARTICIPANTS: Adult patients (aged ≥ 18 years) with ICH within 8 hours of onset. EXCLUSION CRITERIA: Exclusion criteria were ICH secondary to anticoagulation, thrombolysis, trauma or a known underlying structural abnormality; patients for whom tranexamic acid was thought to be contraindicated; prestroke dependence (i.e. patients with a modified Rankin Scale [mRS] score > 4); life expectancy < 3 months; and a Glasgow Coma Scale score of < 5. INTERVENTIONS: Participants, allocated by randomisation, received 1 g of an intravenous tranexamic acid bolus followed by an 8-hour 1-g infusion or matching placebo (i.e. 0.9% saline). MAIN OUTCOME MEASURE: The primary outcome was functional status (death or dependency) at day 90, which was measured by the shift in the mRS score, using ordinal logistic regression, with adjustment for stratification and minimisation criteria. RESULTS: A total of 2325 participants (tranexamic acid, n = 1161; placebo, n = 1164) were recruited from 124 hospitals in 12 countries between 2013 and 2017. Treatment groups were well balanced at baseline. The primary outcome was determined for 2307 participants (tranexamic acid, n = 1152; placebo, n = 1155). There was no statistically significant difference between the treatment groups for the primary outcome of functional status at day 90 [adjusted odds ratio (aOR) 0.88, 95% confidence interval (CI) 0.76 to 1.03; p = 0.11]. Although there were fewer deaths by day 7 in the tranexamic acid group (aOR 0.73, 95% CI 0.53 to 0.99; p = 0.041), there was no difference in case fatality at 90 days (adjusted hazard ratio 0.92, 95% CI 0.77 to 1.10; p = 0.37). Fewer patients experienced serious adverse events (SAEs) after treatment with tranexamic acid than with placebo by days 2 (p = 0.027), 7 (p = 0.020) and 90 (p = 0.039). There was no increase in thromboembolic events or seizures. LIMITATIONS: Despite attempts to enrol patients rapidly, the majority of participants were enrolled and treated > 4.5 hours after stroke onset. Pragmatic inclusion criteria led to a heterogeneous population of participants, some of whom had very large strokes. Although 12 countries enrolled participants, the majority (82.1%) were from the UK. CONCLUSIONS: Tranexamic acid did not affect a patient's functional status at 90 days after ICH, despite there being significant modest reductions in early death (by 7 days), haematoma expansion and SAEs, which is consistent with an antifibrinolytic effect. Tranexamic acid was safe, with no increase in thromboembolic events. FUTURE WORK: Future work should focus on enrolling and treating patients early after stroke and identify which participants are most likely to benefit from haemostatic therapy. Large randomised trials are needed. TRIAL REGISTRATION: Current Controlled Trials ISRCTN93732214. FUNDING: This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 35. See the NIHR Journals Library website for further project information. The project was also funded by the Pragmatic Trials, UK, funding call and the Swiss Heart Foundation in Switzerland.


BACKGROUND: Stroke caused by bleeding in the brain [i.e. an intracerebral haemorrhage (ICH)] is a medical emergency. Around one-third of such strokes are complicated by continuing bleeding, which usually occurs within the first few hours after trauma and childbirth, and is associated with death or severe disability. Tranexamic acid is a drug that is seen to reduce death from bleeding after trauma and childbirth. METHODS: The study enrolled adults within 8 hours of an ICH into this large randomised trial. Half of the participants were given an injection of tranexamic acid and the other half placebo (in the form of salt water). The main aim of the trial was to measure changes in recovery by a telephone questionnaire on how much the person was able to do or needed help with 90 days after the stroke (i.e. functional status). Other measures included amount of brain bleeding, complications after stroke (serious adverse events), drug side effects and death within 7 days of stroke. RESULTS: A total of 2325 participants from 124 hospitals in 12 countries were enrolled between 2013 and 2017. Participants treated with tranexamic acid had no significant difference in functional status 90 days after stroke. There were small but significant reductions in brain bleeding, death in the first 7 days and complications after stroke, and tranexamic acid was safe with no increased side effects. CONCLUSION: Treatment with tranexamic acid did not result in a significant improvement in recovery at 90 days (i.e. functional status), despite small reductions in the number of early deaths, amount of brain bleeding and the number of complications. Larger trials are needed to confirm if these small benefits observed after treatment with tranexamic acid can significantly improve functional status after stroke due to bleeding in the brain (ICH).


Assuntos
Antifibrinolíticos/uso terapêutico , Hemorragia Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/terapia , Ácido Tranexâmico/uso terapêutico , Administração Intravenosa , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Europa (Continente) , Feminino , Escala de Coma de Glasgow , Humanos , Masculino , Estudos Prospectivos , Qualidade de Vida , Avaliação da Tecnologia Biomédica
9.
Health Technol Assess ; 22(48): 1-76, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30179153

RESUMO

BACKGROUND: Two antiplatelet agents are better than one for preventing recurrent stroke after acute ischaemic stroke or transient ischaemic attack (TIA). Therefore, intensive treatment with three agents might be better still, providing it does not cause undue bleeding. OBJECTIVE: To compare the safety and efficacy of intensive therapy with guideline antiplatelet therapy for acute ischaemic stroke and TIA. DESIGN: International prospective randomised open-label blinded end-point parallel-group superiority clinical trial. SETTING: Acute hospitals at 106 sites in four countries. PARTICIPANTS: Patients > 50 years of age with acute non-cardioembolic ischaemic stroke or TIA within 48 hours of ictus (stroke). INTERVENTIONS: Participants were allocated at random by computer to 1 month of intensive (combined aspirin, clopidogrel and dipyridamole) or guideline (combined aspirin and dipyridamole, or clopidogrel alone) antiplatelet agents, and followed for 90 days. MAIN OUTCOME MEASURES: The primary outcome was the incidence and severity of any recurrent stroke (ischaemic, haemorrhagic; assessed using the modified Rankin Scale) or TIA within 90 days by blinded telephone follow-up. Analysis using ordinal logistic regression was by intention to treat. Other outcomes included bleeding and its severity, death, myocardial infarction (MI), disability, mood, cognition and quality of life. RESULTS: The trial was stopped early on the recommendation of the Data Monitoring Committee after recruitment of 3096 participants (intensive, n = 1556; guideline, n = 1540) from 106 hospitals in four countries between April 2009 and March 2016. The incidence and severity of recurrent stroke or TIA did not differ between intensive and guideline therapy in 3070 (99.2%) participants with data [93 vs. 105 stroke/TIA events; adjusted common odds ratio 0.90, 95% confidence interval (CI) 0.67 to 1.20; p = 0.47]. Major (encompassing fatal) bleeding was increased with intensive as compared with guideline therapy [39 vs. 17 participants; adjusted hazard ratio (aHR) 2.23, 95% CI 1.25 to 3.96; p = 0.006]. There were no differences between the treatment groups in all-cause mortality, or the composite of death, stroke, MI and major bleeding (aHR 1.02, 95% CI 0.77 to 1.35; p = 0.88). LIMITATIONS: Patients and investigators were not blinded to treatment. The comparator group comprised two guideline strategies because of changes in national guidelines during the trial. The trial was stopped early, thereby reducing its statistical power. CONCLUSIONS: The use of three antiplatelet agents is associated with increased bleeding without any significant reduction in recurrence of stroke or TIA. FUTURE WORK: The safety and efficacy of dual antiplatelet therapy (combined aspirin and clopidogrel) versus aspirin remains to be defined. Further research is required on identifying individual patient response to antiplatelets, and the relationship between response and the subsequent risks of vascular recurrent events and bleeding complications. TRIAL REGISTRATION: Current Controlled Trials ISRCTN47823388. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 48. See the NIHR Journal Library website for further project information. The Triple Antiplatelets for Reducing Dependency after Ischaemic Stroke (TARDIS) vanguard phase was funded by the British Heart Foundation (grant PG/08/083/25779, from 1 April 2009 to 30 September 2012) and indirect funding was provided by the Stroke Association through its funding of the Stroke Trials Unit, Division of Clinical Neuroscience, University of Nottingham, Nottingham, UK. There was no commercial support for the trial and antiplatelet drugs were sourced locally at each site. The trial was sponsored by the University of Nottingham.


Assuntos
Ataque Isquêmico Transitório/prevenção & controle , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Aspirina/uso terapêutico , Clopidogrel/uso terapêutico , Dipiridamol/uso terapêutico , Quimioterapia Combinada , Feminino , Hemorragia/induzido quimicamente , Humanos , Ataque Isquêmico Transitório/tratamento farmacológico , Ataque Isquêmico Transitório/mortalidade , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/efeitos adversos , Estudos Prospectivos , Qualidade de Vida , Recidiva , Projetos de Pesquisa , Índice de Gravidade de Doença , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/mortalidade
10.
BMC Res Notes ; 11(1): 379, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29895329

RESUMO

OBJECTIVE: We present the statistical analysis plan of a prespecified Tranexamic Acid for Hyperacute Primary Intracerebral Haemorrhage (TICH)-2 sub-study aiming to investigate, if tranexamic acid has a different effect in intracerebral haemorrhage patients with the spot sign on admission compared to spot sign negative patients. The TICH-2 trial recruited above 2000 participants with intracerebral haemorrhage arriving in hospital within 8 h after symptom onset. They were included irrespective of radiological signs of on-going haematoma expansion. Participants were randomised to tranexamic acid versus matching placebo. In this subgroup analysis, we will include all participants in TICH-2 with a computed tomography angiography on admission allowing adjudication of the participants' spot sign status. RESULTS: Primary outcome will be the ability of tranexamic acid to limit absolute haematoma volume on computed tomography at 24 h (± 12 h) after randomisation among spot sign positive and spot sign negative participants, respectively. Within all outcome measures, the effect of tranexamic acid in spot sign positive/negative participants will be compared using tests of interaction. This sub-study will investigate the important clinical hypothesis that spot sign positive patients might benefit more from administration of tranexamic acid compared to spot sign negative patients. Trial registration ISRCTN93732214 ( http://www.isrctn.com ).


Assuntos
Antifibrinolíticos/farmacologia , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/tratamento farmacológico , Interpretação Estatística de Dados , Hematoma/diagnóstico por imagem , Hematoma/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Ácido Tranexâmico/farmacologia , Antifibrinolíticos/administração & dosagem , Progressão da Doença , Humanos , Ácido Tranexâmico/administração & dosagem
11.
Lancet ; 391(10135): 2107-2115, 2018 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-29778325

RESUMO

BACKGROUND: Tranexamic acid can prevent death due to bleeding after trauma and post-partum haemorrhage. We aimed to assess whether tranexamic acid reduces haematoma expansion and improves outcome in adults with stroke due to intracerebral haemorrhage. METHODS: We did an international, randomised placebo-controlled trial in adults with intracerebral haemorrhage from acute stroke units at 124 hospital sites in 12 countries. Participants were randomly assigned (1:1) to receive 1 g intravenous tranexamic acid bolus followed by an 8 h infusion of 1 g tranexamic acid or a matching placebo, within 8 h of symptom onset. Randomisation was done centrally in real time via a secure website, with stratification by country and minimisation on key prognostic factors. Treatment allocation was concealed from patients, outcome assessors, and all other health-care workers involved in the trial. The primary outcome was functional status at day 90, measured by shift in the modified Rankin Scale, using ordinal logistic regression with adjustment for stratification and minimisation criteria. All analyses were done on an intention-to-treat basis. This trial is registered with the ISRCTN registry, number ISRCTN93732214. FINDINGS: We recruited 2325 participants between March 1, 2013, and Sept 30, 2017. 1161 patients received tranexamic acid and 1164 received placebo; the treatment groups were well balanced at baseline. The primary outcome was assessed for 2307 (99%) participants. The primary outcome, functional status at day 90, did not differ significantly between the groups (adjusted odds ratio [aOR] 0·88, 95% CI 0·76-1·03, p=0·11). Although there were fewer deaths by day 7 in the tranexamic acid group (101 [9%] deaths in the tranexamic acid group vs 123 [11%] deaths in the placebo group; aOR 0·73, 0·53-0·99, p=0·0406), there was no difference in case fatality at 90 days (250 [22%] vs 249 [21%]; adjusted hazard ratio 0·92, 95% CI 0·77-1·10, p=0·37). Fewer patients had serious adverse events after tranexamic acid than after placebo by days 2 (379 [33%] patients vs 417 [36%] patients), 7 (456 [39%] vs 497 [43%]), and 90 (521 [45%] vs 556 [48%]). INTERPRETATION: Functional status 90 days after intracerebral haemorrhage did not differ significantly between patients who received tranexamic acid and those who received placebo, despite a reduction in early deaths and serious adverse events. Larger randomised trials are needed to confirm or refute a clinically significant treatment effect. FUNDING: National Institute of Health Research Health Technology Assessment Programme and Swiss Heart Foundation.


Assuntos
Antifibrinolíticos/uso terapêutico , Hemorragia Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/etiologia , Ácido Tranexâmico/uso terapêutico , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Hemorragia Cerebral/complicações , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/terapia , Resultado do Tratamento , Adulto Jovem
12.
BMJ Open ; 8(2): e019930, 2018 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-29431141

RESUMO

OBJECTIVES: To test whether administration of the antifibrinolytic drug tranexamic acid (TXA) in patients with spontaneous intracerebral haemorrhage (SICH) leads to increased prevalence of diffusion-weighted MRI-defined hyperintense ischaemic lesions (primary hypothesis) or reduced perihaematomal oedema volume, perihaematomal diffusion restriction and residual MRI-defined SICH-related tissue damage (secondary hypotheses). DESIGN: MRI substudy nested within the double-blind randomised controlled Tranexamic Acid for Hyperacute Primary Intracerebral Haemorrhage (TICH)-2 trial (ISRCTN93732214). SETTING: International multicentre hospital-based study. PARTICIPANTS: Eligible adults consented and randomised in the TICH-2 trial who were also able to undergo MRI scanning. To address the primary hypothesis, a sample size of n=280 will allow detection of a 10% relative increase in prevalence of diffusion-weighted imaging (DWI) hyperintense lesions in the TXA group with 5% significance, 80% power and 5% imaging data rejection. INTERVENTIONS: TICH-2 MRI substudy participants will undergo MRI scanning using a standardised protocol at day ~5 and day ~90 after randomisation. Clinical assessments, randomisation to TXA or placebo and participant follow-up will be performed as per the TICH-2 trial protocol. CONCLUSION: The TICH-2 MRI substudy will test whether TXA increases the incidence of new DWI-defined ischaemic lesions or reduces perihaematomal oedema or final ICH lesion volume in the context of SICH. ETHICS AND DISSEMINATION: The TICH-2 trial obtained ethical approval from East Midlands - Nottingham 2 Research Ethics Committee (12/EM/0369) and an amendment to allow the TICH-2 MRI sub study was approved in April 2015 (amendment number SA02/15). All findings will be published in peer-reviewed journals. The primary outcome results will also be presented at a relevant scientific meeting. TRIAL REGISTRATION NUMBER: ISRCTN93732214; Pre-results.


Assuntos
Antifibrinolíticos/administração & dosagem , Encéfalo/efeitos dos fármacos , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/tratamento farmacológico , Ácido Tranexâmico/administração & dosagem , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Método Duplo-Cego , Humanos , Cooperação Internacional , Modelos Logísticos , Imageamento por Ressonância Magnética , Projetos de Pesquisa , Resultado do Tratamento
13.
Int J Stroke ; 13(5): 530-538, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28906205

RESUMO

Rationale The pathophysiology of most lacunar stroke, a form of small vessel disease, is thought to differ from large artery atherothrombo- or cardio-embolic stroke. Licensed drugs, isosorbide mononitrate and cilostazol, have promising mechanisms of action to support their testing to prevent stroke recurrence, cognitive impairment, or radiological progression after lacunar stroke. Aim LACI-1 will assess the tolerability, safety, and efficacy, by dose, of isosorbide mononitrate and cilostazol, alone and in combination, in patients with ischemic lacunar stroke. Sample size A sample of 60 provides 80+% power (significance 0.05) to detect a difference of 35% (90% versus 55%) between those reaching target dose on one versus both drugs. Methods and design LACI-1 is a phase IIa partial factorial, dose-escalation, prospective, randomized, open label, blinded endpoint trial. Participants are randomized to isosorbide mononitrate and/or cilostazol for 11 weeks with dose escalation to target as tolerated in two centers (Edinburgh, Nottingham). At three visits, tolerability, safety, blood pressure, pulse wave velocity, and platelet function are assessed, plus magnetic resonance imaging to assess cerebrovascular reactivity in a subgroup. Study outcomes Primary: proportion of patients completing study achieving target maximum dose. Secondary symptoms whilst taking medications; safety (hemorrhage, recurrent vascular events, falls); blood pressure, platelet function, arterial stiffness, and cerebrovascular reactivity. Discussion This study will inform the design of a larger phase III trial of isosorbide mononitrate and cilostazol in lacunar stroke, whilst providing data on the drugs' effects on vascular and platelet function. Trial registration ISRCTN (ISRCTN12580546) and EudraCT (2015-001953-33).


Assuntos
Cilostazol/uso terapêutico , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/prevenção & controle , Demência/prevenção & controle , Dinitrato de Isossorbida/análogos & derivados , Vasodilatadores/uso terapêutico , Fatores Etários , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/tratamento farmacológico , Demência/etiologia , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Dinitrato de Isossorbida/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Índice de Gravidade de Doença , Resultado do Tratamento , Reino Unido
14.
Lancet ; 391(10123): 850-859, 2018 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-29274727

RESUMO

BACKGROUND: Intensive antiplatelet therapy with three agents might be more effective than guideline treatment for preventing recurrent events in patients with acute cerebral ischaemia. We aimed to compare the safety and efficacy of intensive antiplatelet therapy (combined aspirin, clopidogrel, and dipyridamole) with that of guideline-based antiplatelet therapy. METHODS: We did an international, prospective, randomised, open-label, blinded-endpoint trial in adult participants with ischaemic stroke or transient ischaemic attack (TIA) within 48 h of onset. Participants were assigned in a 1:1 ratio using computer randomisation to receive loading doses and then 30 days of intensive antiplatelet therapy (combined aspirin 75 mg, clopidogrel 75 mg, and dipyridamole 200 mg twice daily) or guideline-based therapy (comprising either clopidogrel alone or combined aspirin and dipyridamole). Randomisation was stratified by country and index event, and minimised with prognostic baseline factors, medication use, time to randomisation, stroke-related factors, and thrombolysis. The ordinal primary outcome was the combined incidence and severity of any recurrent stroke (ischaemic or haemorrhagic; assessed using the modified Rankin Scale) or TIA within 90 days, as assessed by central telephone follow-up with masking to treatment assignment, and analysed by intention to treat. This trial is registered with the ISRCTN registry, number ISRCTN47823388. FINDINGS: 3096 participants (1556 in the intensive antiplatelet therapy group, 1540 in the guideline antiplatelet therapy group) were recruited from 106 hospitals in four countries between April 7, 2009, and March 18, 2016. The trial was stopped early on the recommendation of the data monitoring committee. The incidence and severity of recurrent stroke or TIA did not differ between intensive and guideline therapy (93 [6%] participants vs 105 [7%]; adjusted common odds ratio [cOR] 0·90, 95% CI 0·67-1·20, p=0·47). By contrast, intensive antiplatelet therapy was associated with more, and more severe, bleeding (adjusted cOR 2·54, 95% CI 2·05-3·16, p<0·0001). INTERPRETATION: Among patients with recent cerebral ischaemia, intensive antiplatelet therapy did not reduce the incidence and severity of recurrent stroke or TIA, but did significantly increase the risk of major bleeding. Triple antiplatelet therapy should not be used in routine clinical practice. FUNDING: National Institutes of Health Research Health Technology Assessment Programme, British Heart Foundation.


Assuntos
Aspirina/farmacologia , Isquemia Encefálica/tratamento farmacológico , Dipiridamol/farmacologia , Ticlopidina/análogos & derivados , Doença Aguda , Idoso , Aspirina/administração & dosagem , Aspirina/efeitos adversos , Clopidogrel , Dinamarca/epidemiologia , Dipiridamol/administração & dosagem , Dipiridamol/efeitos adversos , Quimioterapia Combinada , Feminino , Georgia/epidemiologia , Hemorragia/induzido quimicamente , Humanos , Isquemia/tratamento farmacológico , Isquemia/patologia , Ataque Isquêmico Transitório/induzido quimicamente , Ataque Isquêmico Transitório/epidemiologia , Masculino , Pessoa de Meia-Idade , Nova Zelândia/epidemiologia , Inibidores da Agregação Plaquetária , Estudos Prospectivos , Recidiva , Projetos de Pesquisa/normas , Medição de Risco , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Terapia Trombolítica/métodos , Ticlopidina/administração & dosagem , Ticlopidina/efeitos adversos , Ticlopidina/farmacologia , Resultado do Tratamento , Reino Unido/epidemiologia
15.
Trials ; 18(1): 607, 2017 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-29262841

RESUMO

RATIONALE: Aside from blood pressure lowering, treatment options for intracerebral haemorrhage remain limited and a proportion of patients will undergo early haematoma expansion with resultant significant morbidity and mortality. Tranexamic acid (TXA), an anti-fibrinolytic drug, has been shown to significantly reduce mortality in patients, who are bleeding following trauma, when given rapidly. TICH-2 is testing whether TXA is effective at improving outcome in spontaneous intracerebral haemorrhage (SICH). METHODS AND DESIGN: TICH-2 is a pragmatic, phase III, prospective, double-blind, randomised placebo-controlled trial. Two thousand adult (aged ≥ 18 years) patients with an acute SICH, within 8 h of stroke onset, will be randomised to receive TXA or the placebo control. The primary outcome is ordinal shift of modified Rankin Scale score at day 90. Analyses will be performed using intention-to-treat. RESULTS: This paper and its attached appendices describe the statistical analysis plan (SAP) for the trial and were developed and published prior to database lock and unblinding to treatment allocation. The SAP includes details of analyses to be undertaken and unpopulated tables which will be reported in the primary and key secondary publications. The database will be locked in early 2018, ready for publication of the results later in the same year. DISCUSSION: The SAP details the analyses that will be done to avoid bias arising from prior knowledge of the study findings. The trial will determine whether TXA can improve outcome after SICH, which currently has no definitive therapy. TRIAL REGISTRATION: ISRCTN registry, ID: ISRCTN93732214 . Registered on 17 January 2013.


Assuntos
Antifibrinolíticos/uso terapêutico , Hemorragia Cerebral/tratamento farmacológico , Ácido Tranexâmico/uso terapêutico , Antifibrinolíticos/efeitos adversos , Hemorragia Cerebral/diagnóstico , Protocolos Clínicos , Interpretação Estatística de Dados , Avaliação da Deficiência , Método Duplo-Cego , Humanos , Análise de Intenção de Tratamento , Modelos Logísticos , Estudos Prospectivos , Projetos de Pesquisa , Fatores de Tempo , Ácido Tranexâmico/efeitos adversos , Resultado do Tratamento
16.
Stroke Res Treat ; 2017: 7365684, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28630782

RESUMO

BACKGROUND: The TARDIS trial assessed the safety and efficacy of intensive versus guideline antiplatelet agents given for one month in patients with acute stroke or TIA. The aim of this substudy was to assess the effect of antiplatelet agents taken at baseline on platelet function reactivity and activation. METHODS: Platelet function, assessed by remotely measured surface expression of P-selectin, was assessed in patients at their time of randomisation. Data are median fluorescence values. RESULTS: The aspirin P-selectin test demonstrated that platelet expression was lower in 494 patients taking aspirin than in 162 patients not: mean 210 (SD 188) versus 570 (435), difference 360.3 (95% CI 312.2-408.4) (2p < 0.001). Aspirin did not suppress P-selectin levels below 500 units in 23 (4.7%) patients. The clopidogrel test showed that platelet reactivity was lower in 97 patients taking clopidogrel than in 585 patients not: 655 (296) versus 969 (315), difference 314.5 (95% CI 247.3-381.7) (2p < 0.001). Clopidogrel did not suppress P-selectin level below 860 units in 24 (24.7%) patients. CONCLUSIONS: Aspirin and clopidogrel suppress stimulated platelet P-selectin, although one-quarter of patients on clopidogrel have high on-treatment platelet reactivity. Platelet function testing may be performed remotely in the context of a large multicentre trial. Trial registration ISRCTN47823388.

17.
Wellcome Open Res ; 2: 120, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29417096

RESUMO

INTRODUCTION: The Anti-fibrinolytics Trialists Collaboration aims to increase knowledge about the effectiveness and safety of anti-fibrinolytic treatment by conducting individual patient data (IPD) meta-analyses of randomised trials. This article presents the statistical analysis plan for an IPD meta-analysis of the effects of anti-fibrinolytics for acute intracranial haemorrhage. METHODS: The protocol for the IPD meta-analysis has been registered with PROSPERO (CRD42019128260). We will conduct an individual patient data meta-analysis of randomised controlled trials with 500 patients or more assessing the effects of anti-fibrinolytics in acute intracranial haemorrhage. The primary outcomes will be 1) death from stroke or head injury within 30 days of randomisation, and 2) death from stroke or head injury, or dependency within 90 days of randomisation. The primary outcomes will be limited to patients treated within three hours of injury or stroke onset. We will report treatment effects using odds ratios and 95% confidence intervals. We use logistic regression models to examine how the effect of anti-fibrinolytics vary by time to treatment, severity of intracranial bleeding, and age. We will also examine the effect of anti-fibrinolytics on secondary outcomes including death, dependency, vascular occlusive events, seizures, and neurological outcomes. Secondary outcomes will be assessed in all patients irrespective of time of treatment. All analyses will be conducted on an intention-to-treat basis. CONCLUSIONS: This IPD meta-analysis will examine important clinical questions about the effects of anti-fibrinolytic treatment in patients with intracranial haemorrhage that cannot be answered using aggregate data. With IPD we can examine how effects vary by time to treatment, bleeding severity, and age, to gain better understanding of the balance of benefit and harms on which to base recommendations for practice.

18.
Int J Stroke ; 12(5): 524-538, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27811309

RESUMO

Background The risk of recurrence following ischemic stroke or transient ischemic attack is highest immediately after the event. Antiplatelet agents are effective in reducing the risk of recurrence and two agents are superior to one in the early phase after ictus. Design The triple antiplatelets for reducing dependency after ischemic stroke trial was an international multicenter prospective randomized open-label blinded-endpoint trial that assessed the safety and efficacy of short-term intensive antiplatelet therapy with three agents (combined aspirin, clopidogrel and dipyridamole) as compared with guideline treatment in acute ischemic stroke or transient ischemic attack. The primary outcome was stroke recurrence and its severity, measured using the modified Rankin Scale at 90 days. Secondary outcomes included recurrent vascular events, functional measures (cognition, disability, mood, quality of life), and safety (bleeding, death, serious adverse events). Data are number (%) or mean (standard deviation, SD). Results Recruitment ran from April 2009 to March 2016; 3096 patients were recruited from 106 sites in four countries (Denmark 1.6%, Georgia 2.7%, New Zealand 0.2%, UK 95.4%). Randomization characteristics included: age 69.0 (10.1) years; male 1945 (62.8%); time onset to randomization 29.4 (11.9) h; stroke severity (National Institutes for Health Stroke Scale) 2.8 (3.6); blood pressure 143.5 (18.2)/79.5 (11.4) mmHg; IS 2143 (69.2%), transient ischemic attack 953 (30.8%). Conclusion Triple antiplatelets for reducing dependency after ischemic stroke was a large trial of intensive/triple antiplatelet therapy in acute ischemic stroke and transient ischemic attack, and included participants from four predominantly Caucasian countries who were representative of patients in many western stroke services.


Assuntos
Aspirina/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Dipiridamol/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Ticlopidina/análogos & derivados , Idoso , Aspirina/efeitos adversos , Isquemia Encefálica/mortalidade , Isquemia Encefálica/psicologia , Clopidogrel , Dipiridamol/efeitos adversos , Quimioterapia Combinada , Feminino , Humanos , Masculino , Inibidores da Agregação Plaquetária/efeitos adversos , Índice de Gravidade de Doença , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/psicologia , Ticlopidina/efeitos adversos , Ticlopidina/uso terapêutico , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA