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1.
N Engl J Med ; 381(22): 2103-2113, 2019 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-31774955

RESUMEN

BACKGROUND: The choice of drugs for patients with status epilepticus that is refractory to treatment with benzodiazepines has not been thoroughly studied. METHODS: In a randomized, blinded, adaptive trial, we compared the efficacy and safety of three intravenous anticonvulsive agents - levetiracetam, fosphenytoin, and valproate - in children and adults with convulsive status epilepticus that was unresponsive to treatment with benzodiazepines. The primary outcome was absence of clinically evident seizures and improvement in the level of consciousness by 60 minutes after the start of drug infusion, without additional anticonvulsant medication. The posterior probabilities that each drug was the most or least effective were calculated. Safety outcomes included life-threatening hypotension or cardiac arrhythmia, endotracheal intubation, seizure recurrence, and death. RESULTS: A total of 384 patients were enrolled and randomly assigned to receive levetiracetam (145 patients), fosphenytoin (118), or valproate (121). Reenrollment of patients with a second episode of status epilepticus accounted for 16 additional instances of randomization. In accordance with a prespecified stopping rule for futility of finding one drug to be superior or inferior, a planned interim analysis led to the trial being stopped. Of the enrolled patients, 10% were determined to have had psychogenic seizures. The primary outcome of cessation of status epilepticus and improvement in the level of consciousness at 60 minutes occurred in 68 patients assigned to levetiracetam (47%; 95% credible interval, 39 to 55), 53 patients assigned to fosphenytoin (45%; 95% credible interval, 36 to 54), and 56 patients assigned to valproate (46%; 95% credible interval, 38 to 55). The posterior probability that each drug was the most effective was 0.41, 0.24, and 0.35, respectively. Numerically more episodes of hypotension and intubation occurred in the fosphenytoin group and more deaths occurred in the levetiracetam group than in the other groups, but these differences were not significant. CONCLUSIONS: In the context of benzodiazepine-refractory convulsive status epilepticus, the anticonvulsant drugs levetiracetam, fosphenytoin, and valproate each led to seizure cessation and improved alertness by 60 minutes in approximately half the patients, and the three drugs were associated with similar incidences of adverse events. (Funded by the National Institute of Neurological Disorders and Stroke; ESETT ClinicalTrials.gov number, NCT01960075.).


Asunto(s)
Anticonvulsivantes/uso terapéutico , Levetiracetam/uso terapéutico , Fenitoína/análogos & derivados , Estado Epiléptico/tratamiento farmacológico , Ácido Valproico/uso terapéutico , Adolescente , Adulto , Anticonvulsivantes/efectos adversos , Benzodiazepinas/uso terapéutico , Niño , Preescolar , Método Doble Ciego , Resistencia a Medicamentos , Femenino , Humanos , Hipotensión/inducido químicamente , Infusiones Intravenosas , Inyecciones Intramusculares , Levetiracetam/efectos adversos , Masculino , Persona de Mediana Edad , Fenitoína/efectos adversos , Fenitoína/uso terapéutico , Ácido Valproico/efectos adversos , Adulto Joven
2.
Lancet ; 395(10231): 1217-1224, 2020 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-32203691

RESUMEN

BACKGROUND: Benzodiazepine-refractory, or established, status epilepticus is thought to be of similar pathophysiology in children and adults, but differences in underlying aetiology and pharmacodynamics might differentially affect response to therapy. In the Established Status Epilepticus Treatment Trial (ESETT) we compared the efficacy and safety of levetiracetam, fosphenytoin, and valproate in established status epilepticus, and here we describe our results after extending enrolment in children to compare outcomes in three age groups. METHODS: In this multicentre, double-blind, response-adaptive, randomised controlled trial, we recruited patients from 58 hospital emergency departments across the USA. Patients were eligible for inclusion if they were aged 2 years or older, had been treated for a generalised convulsive seizure of longer than 5 min duration with adequate doses of benzodiazepines, and continued to have persistent or recurrent convulsions in the emergency department for at least 5 min and no more than 30 min after the last dose of benzodiazepine. Patients were randomly assigned in a response-adaptive manner, using Bayesian methods and stratified by age group (<18 years, 18-65 years, and >65 years), to levetiracetam, fosphenytoin, or valproate. All patients, investigators, study staff, and pharmacists were masked to treatment allocation. The primary outcome was absence of clinically apparent seizures with improved consciousness and without additional antiseizure medication at 1 h from start of drug infusion. The primary safety outcome was life-threatening hypotension or cardiac arrhythmia. The efficacy and safety outcomes were analysed by intention to treat. This study is registered in ClinicalTrials.gov, NCT01960075. FINDINGS: Between Nov 3, 2015, and Dec 29, 2018, we enrolled 478 patients and 462 unique patients were included: 225 children (aged <18 years), 186 adults (18-65 years), and 51 older adults (>65 years). 175 (38%) patients were randomly assigned to levetiracetam, 142 (31%) to fosphenyltoin, and 145 (31%) were to valproate. Baseline characteristics were balanced across treatments within age groups. The primary efficacy outcome was met in those treated with levetiracetam for 52% (95% credible interval 41-62) of children, 44% (33-55) of adults, and 37% (19-59) of older adults; with fosphenytoin in 49% (38-61) of children, 46% (34-59) of adults, and 35% (17-59) of older adults; and with valproate in 52% (41-63) of children, 46% (34-58) of adults, and 47% (25-70) of older adults. No differences were detected in efficacy or primary safety outcome by drug within each age group. With the exception of endotracheal intubation in children, secondary safety outcomes did not significantly differ by drug within each age group. INTERPRETATION: Children, adults, and older adults with established status epilepticus respond similarly to levetiracetam, fosphenytoin, and valproate, with treatment success in approximately half of patients. Any of the three drugs can be considered as a potential first-choice, second-line drug for benzodiazepine-refractory status epilepticus. FUNDING: National Institute of Neurological Disorders and Stroke, National Institutes of Health.


Asunto(s)
Anticonvulsivantes/administración & dosificación , Levetiracetam/administración & dosificación , Fenitoína/análogos & derivados , Estado Epiléptico/tratamiento farmacológico , Ácido Valproico/administración & dosificación , Adolescente , Adulto , Distribución por Edad , Factores de Edad , Anciano , Anciano de 80 o más Años , Anticonvulsivantes/efectos adversos , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Lactante , Levetiracetam/efectos adversos , Masculino , Persona de Mediana Edad , Fenitoína/administración & dosificación , Fenitoína/efectos adversos , Ácido Valproico/efectos adversos , Adulto Joven
3.
Lancet ; 395(10217): 42-52, 2020 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-31839279

RESUMEN

BACKGROUND: Antivirals are infrequently prescribed in European primary care for influenza-like illness, mostly because of perceived ineffectiveness in real world primary care and because individuals who will especially benefit have not been identified in independent trials. We aimed to determine whether adding antiviral treatment to usual primary care for patients with influenza-like illness reduces time to recovery overall and in key subgroups. METHODS: We did an open-label, pragmatic, adaptive, randomised controlled trial of adding oseltamivir to usual care in patients aged 1 year and older presenting with influenza-like illness in primary care. The primary endpoint was time to recovery, defined as return to usual activities, with fever, headache, and muscle ache minor or absent. The trial was designed and powered to assess oseltamivir benefit overall and in 36 prespecified subgroups defined by age, comorbidity, previous symptom duration, and symptom severity, using a Bayesian piece-wise exponential primary analysis model. The trial is registered with the ISRCTN Registry, number ISRCTN 27908921. FINDINGS: Between Jan 15, 2016, and April 12, 2018, we recruited 3266 participants in 15 European countries during three seasonal influenza seasons, allocated 1629 to usual care plus oseltamivir and 1637 to usual care, and ascertained the primary outcome in 1533 (94%) and 1526 (93%). 1590 (52%) of 3059 participants had PCR-confirmed influenza infection. Time to recovery was shorter in participants randomly assigned to oseltamivir (hazard ratio 1·29, 95% Bayesian credible interval [BCrI] 1·20-1·39) overall and in 30 of the 36 prespecified subgroups, with estimated hazard ratios ranging from 1·13 to 1·72. The estimated absolute mean benefit from oseltamivir was 1·02 days (95% [BCrI] 0·74-1·31) overall, and in the prespecified subgroups, ranged from 0·70 (95% BCrI 0·30-1·20) in patients younger than 12 years, with less severe symptoms, no comorbidities, and shorter previous illness duration to 3·20 (95% BCrI 1·00-5·50) in patients aged 65 years or older who had more severe illness, comorbidities, and longer previous illness duration. Regarding harms, an increased burden of vomiting or nausea was observed in the oseltamivir group. INTERPRETATION: Primary care patients with influenza-like illness treated with oseltamivir recovered one day sooner on average than those managed by usual care alone. Older, sicker patients with comorbidities and longer previous symptom duration recovered 2-3 days sooner. FUNDING: European Commission's Seventh Framework Programme.


Asunto(s)
Antivirales/administración & dosificación , Gripe Humana/terapia , Oseltamivir/administración & dosificación , Atención Primaria de Salud/métodos , Adolescente , Adulto , Anciano , Antivirales/uso terapéutico , Niño , Preescolar , Terapia Combinada , Europa (Continente) , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Oseltamivir/uso terapéutico , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
4.
Am J Hematol ; 92(7): 622-631, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28370266

RESUMEN

Clinical and preclinical data demonstrate that altered pulmonary physiology (including increased inflammation, increased blood flow, airway resistance, and hyper-reactivity) is an intrinsic component of Sickle Cell Disease (SCD) and may contribute to excess SCD morbidity and mortality. Inhaled corticosteroids (ICS), a safe and effective therapy for pulmonary inflammation in asthma, may ameliorate the altered pulmonary physiologic milieu in SCD. With this single-center, longitudinal, randomized, triple-blind, placebo controlled trial we studied the efficacy and feasibility of ICS in 54 nonasthmatic individuals with SCD. Participants received once daily mometasone furoate 220 mcg dry powder inhalation or placebo for 16 weeks. The primary outcome was feasibility (the number who complete the trial divided by the total number enrolled) with prespecified efficacy outcomes including daily pain score over time (patient reported) and change in soluble vascular cell adhesion molecule (sVCAM) levels between entry and 8-weeks. For the primary outcome of feasibility, the result was 96% (52 of 54, 95% CI 87%-99%) for the intent-to-treat analysis and 83% (45 of 54, 95% CI 71%-91%) for the per-protocol analysis. The adjusted treatment effect of mometasone was a reduction in daily pain score of 1.42 points (95%CI 0.61-2.21, P = 0.001). Mometasone was associated with a reduction in sVCAM levels of 526.94 ng/mL more than placebo (95% CI 50.66-1003.23, P = 0.03). These results support further study of ICS in SCD including multicenter trials and longer durations of treatment. www.clinicaltrials.gov (NCT02061202).


Asunto(s)
Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/tratamiento farmacológico , Dolor/tratamiento farmacológico , Esteroides/administración & dosificación , Molécula 1 de Adhesión Celular Vascular/sangre , Síndrome Torácico Agudo/diagnóstico , Síndrome Torácico Agudo/tratamiento farmacológico , Síndrome Torácico Agudo/etiología , Administración por Inhalación , Adulto , Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/diagnóstico , Antidrepanocíticos/uso terapéutico , Biomarcadores , Comorbilidad , Citocinas/sangre , Femenino , Humanos , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Oportunidad Relativa , Dolor/diagnóstico , Dolor/etiología , Dimensión del Dolor , Pruebas de Función Respiratoria , Esteroides/efectos adversos , Resultado del Tratamiento
5.
Ann Intern Med ; 165(6): 431-8, 2016 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-27273013

RESUMEN

BACKGROUND: Bayesian and adaptive clinical trial designs offer the potential for more efficient processes that result in lower sample sizes and shorter trial durations than traditional designs. OBJECTIVE: To explore the use and potential benefits of Bayesian adaptive clinical trial designs in comparative effectiveness research. DESIGN: Virtual execution of ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial) as if it had been done according to a Bayesian adaptive trial design. SETTING: Comparative effectiveness trial of antihypertensive medications. PATIENTS: Patient data sampled from the more than 42 000 patients enrolled in ALLHAT with publicly available data. MEASUREMENTS: Number of patients randomly assigned between groups, trial duration, observed numbers of events, and overall trial results and conclusions. RESULTS: The Bayesian adaptive approach and original design yielded similar overall trial conclusions. The Bayesian adaptive trial randomly assigned more patients to the better-performing group and would probably have ended slightly earlier. LIMITATIONS: This virtual trial execution required limited resampling of ALLHAT patients for inclusion in RE-ADAPT (REsearch in ADAptive methods for Pragmatic Trials). Involvement of a data monitoring committee and other trial logistics were not considered. CONCLUSION: In a comparative effectiveness research trial, Bayesian adaptive trial designs are a feasible approach and potentially generate earlier results and allocate more patients to better-performing groups. PRIMARY FUNDING SOURCE: National Heart, Lung, and Blood Institute.


Asunto(s)
Teorema de Bayes , Ensayos Clínicos como Asunto/estadística & datos numéricos , Investigación sobre la Eficacia Comparativa/estadística & datos numéricos , Proyectos de Investigación/estadística & datos numéricos , Antihipertensivos/uso terapéutico , Humanos , Hipolipemiantes/uso terapéutico , Infarto del Miocardio/prevención & control
6.
Am Heart J ; 170(6): 1184-94, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26678640

RESUMEN

BACKGROUND: Pulmonary vein antrum isolation (PVI) as a treatment of paroxysmal atrial fibrillation (AF) is associated with a high rate of success; however, outcomes for treating persistent and long-standing persistent AF with PVI alone are substantially lower and often require multiple procedures to maintain long-term freedom from atrial arrhythmias. Foci and/or substrate outside the pulmonary veins, particularly in the left atrial appendage (LAA), has been identified as a key mechanism in the maintenance of persistent AF and long-standing persistent AF. OBJECTIVE: The goals of the study are to evaluate the safety and effectiveness of the LARIAT System to percutaneously isolate and ligate the LAA and to determine if LAA ligation as adjunctive therapy to PVI improves maintenance of sinus rhythm in patients with persistent and long-standing persistent AF. STUDY DESIGN: The trial is a prospective, multicenter, randomized controlled study. The trial design incorporates a Bayesian adaptive design that will randomize a maximum of 600 patients with persistent or long-standing persistent AF to LAA ligation and PVI vs PVI alone in a 2:1 randomization. The primary end points include 30-day safety of the LARIAT procedure and freedom from documented AF, atrial flutter, or atrial tachycardia of more than 30 seconds at 12 months after the PVI off antiarrhythmic drugs. Key secondary outcomes include a composite of cardiovascular death and stroke, as well as quality of life. CONCLUSION: The aMAZE trial will determine if LAA ligation as adjunctive therapy to PVI increases the efficacy of maintaining sinus rhythm in patients with persistent and long-standing persistent AF.


Asunto(s)
Apéndice Atrial/cirugía , Fibrilación Atrial , Ablación por Catéter , Venas Pulmonares/cirugía , Calidad de Vida , Adulto , Anciano , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/psicología , Fibrilación Atrial/cirugía , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos , Electrocardiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Proyectos de Investigación , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Resultado del Tratamiento
7.
Clin Trials ; 11(4): 485-493, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24872363

RESUMEN

BACKGROUND: Bayesian predictive probabilities can be used for interim monitoring of clinical trials to estimate the probability of observing a statistically significant treatment effect if the trial were to continue to its predefined maximum sample size. PURPOSE: We explore settings in which Bayesian predictive probabilities are advantageous for interim monitoring compared to Bayesian posterior probabilities, p-values, conditional power, or group sequential methods. RESULTS: For interim analyses that address prediction hypotheses, such as futility monitoring and efficacy monitoring with lagged outcomes, only predictive probabilities properly account for the amount of data remaining to be observed in a clinical trial and have the flexibility to incorporate additional information via auxiliary variables. LIMITATIONS: Computational burdens limit the feasibility of predictive probabilities in many clinical trial settings. The specification of prior distributions brings additional challenges for regulatory approval. CONCLUSIONS: The use of Bayesian predictive probabilities enables the choice of logical interim stopping rules that closely align with the clinical decision-making process.

8.
J Biopharm Stat ; 24(3): 685-705, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24697532

RESUMEN

We present a Bayesian adaptive design for a confirmatory trial to select a trial's sample size based on accumulating data. During accrual, frequent sample size selection analyses are made and predictive probabilities are used to determine whether the current sample size is sufficient or whether continuing accrual would be futile. The algorithm explicitly accounts for complete follow-up of all patients before the primary analysis is conducted. We refer to this as a Goldilocks trial design, as it is constantly asking the question, "Is the sample size too big, too small, or just right?" We describe the adaptive sample size algorithm, describe how the design parameters should be chosen, and show examples for dichotomous and time-to-event endpoints.


Asunto(s)
Ensayos Clínicos Fase III como Asunto/estadística & datos numéricos , Modelos Estadísticos , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Tamaño de la Muestra , Algoritmos , Teorema de Bayes , Distribución Binomial , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Determinación de Punto Final/estadística & datos numéricos , Femenino , Humanos , Ganglios Linfáticos/patología , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Biopsia del Ganglio Linfático Centinela , Análisis de Supervivencia
9.
JACC Heart Fail ; 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38530701

RESUMEN

Clinical trials are vital for assessing therapeutic interventions. The associated data monitoring committees (DMCs) safeguard patient interests and enhance trial integrity, thus promoting timely, reliable evaluations of those interventions. We face an urgent need to recruit and train new DMC members. The Heart Failure Collaboratory (HFC), a multidisciplinary public-private consortium of academics, trialists, patients, industry representatives, and government agencies, is working to improve the clinical trial ecosystem. The HFC aims to improve clinical trial efficiency and quality by standardizing concepts, and to help meet the demand for experienced individuals on DMCs by creating a standardized approach to training new members. This paper discusses the HFC's training workshop, and an apprenticeship model for new DMC members. It describes opportunities and challenges DMCs face, along with common myths and best practices learned through previous experiences, with an emphasis on data confidentiality and need for quality independent statistical reporting groups.

10.
Nat Med ; 30(4): 1044-1053, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38584166

RESUMEN

Programmed cell death protein 1 (PD-1) inhibitors have modest efficacy as a monotherapy in hepatocellular carcinoma (HCC). A personalized therapeutic cancer vaccine (PTCV) may enhance responses to PD-1 inhibitors through the induction of tumor-specific immunity. We present results from a single-arm, open-label, phase 1/2 study of a DNA plasmid PTCV (GNOS-PV02) encoding up to 40 neoantigens coadministered with plasmid-encoded interleukin-12 plus pembrolizumab in patients with advanced HCC previously treated with a multityrosine kinase inhibitor. Safety and immunogenicity were assessed as primary endpoints, and treatment efficacy and feasibility were evaluated as secondary endpoints. The most common treatment-related adverse events were injection-site reactions, observed in 15 of 36 (41.6%) patients. No dose-limiting toxicities or treatment-related grade ≥3 events were observed. The objective response rate (modified intention-to-treat) per Response Evaluation Criteria in Solid Tumors 1.1 was 30.6% (11 of 36 patients), with 8.3% (3 of 36) of patients achieving a complete response. Clinical responses were associated with the number of neoantigens encoded in the vaccine. Neoantigen-specific T cell responses were confirmed in 19 of 22 (86.4%) evaluable patients by enzyme-linked immunosorbent spot assays. Multiparametric cellular profiling revealed active, proliferative and cytolytic vaccine-specific CD4+ and CD8+ effector T cells. T cell receptor ß-chain (TCRß) bulk sequencing results demonstrated vaccination-enriched T cell clone expansion and tumor infiltration. Single-cell analysis revealed posttreatment T cell clonal expansion of cytotoxic T cell phenotypes. TCR complementarity-determining region cloning of expanded T cell clones in the tumors following vaccination confirmed reactivity against vaccine-encoded neoantigens. Our results support the PTCV's mechanism of action based on the induction of antitumor T cells and show that a PTCV plus pembrolizumab has clinical activity in advanced HCC. ClinicalTrials.gov identifier: NCT04251117 .


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Vacunas , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Anticuerpos Monoclonales Humanizados/efectos adversos , Vacunas/uso terapéutico
11.
Clin Trials ; 10(5): 807-27, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23983160

RESUMEN

BACKGROUND: Randomized clinical trials, particularly for comparative effectiveness research (CER), are frequently criticized for being overly restrictive or untimely for health-care decision making. PURPOSE: Our prospectively designed REsearch in ADAptive methods for Pragmatic Trials (RE-ADAPT) study is a 'proof of concept' to stimulate investment in Bayesian adaptive designs for future CER trials. METHODS: We will assess whether Bayesian adaptive designs offer potential efficiencies in CER by simulating a re-execution of the Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) study using actual data from ALLHAT. RESULTS: We prospectively define seven alternate designs consisting of various combinations of arm dropping, adaptive randomization, and early stopping and describe how these designs will be compared to the original ALLHAT design. We identify the one particular design that would have been executed, which incorporates early stopping and information-based adaptive randomization. LIMITATIONS: While the simulation realistically emulates patient enrollment, interim analyses, and adaptive changes to design, it cannot incorporate key features like the involvement of data monitoring committee in making decisions about adaptive changes. CONCLUSION: This article describes our analytic approach for RE-ADAPT. The next stage of the project is to conduct the re-execution analyses using the seven prespecified designs and the original ALLHAT data.


Asunto(s)
Teorema de Bayes , Investigación sobre la Eficacia Comparativa/métodos , Interpretación Estadística de Datos , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Antihipertensivos/administración & dosificación , Investigación sobre la Eficacia Comparativa/estadística & datos numéricos , Simulación por Computador , Paro Cardíaco/prevención & control , Humanos , Hipolipemiantes/administración & dosificación , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos
12.
J Biopharm Stat ; 23(1): 261-71, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23331235

RESUMEN

Prior to marketing, the long-term safety profile of a new therapy is often uncertain. One recommendation for premarket safety studies is to compare the new therapy to an appropriate control to determine whether the 95% confidence interval of the risk ratio is entirely less than a prespecified threshold (e.g., 1.8). The restriction to the risk ratio, however, has consequences that may not be intended. Risk difference may be a more appropriate measure of risk in this setting when event rates are very low. We propose using a suitable combination of risk ratio and risk difference in demonstrating noninferiority.


Asunto(s)
Ensayos Clínicos como Asunto/efectos adversos , Ensayos Clínicos como Asunto/normas , Oportunidad Relativa , Seguridad del Paciente/normas , Humanos , Factores de Riesgo
13.
Contemp Clin Trials Commun ; 34: 101100, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37388218

RESUMEN

A number of principal investigators may have limited access to biostatisticians, a lack of biostatistical training, or no requirement to complete a timely statistical analysis plan (SAP). SAPs completed early will identify design or implementation weak points, improve protocols, remove the temptation for p-hacking, and enable proper peer review by stakeholders considering funding the trial. An SAP completed at the same time as the study protocol might be the only comprehensive method for at once optimizing sample size, identifying bias, and applying rigor to study design. This ordered corpus of SAP sections with detailed definitions and a variety of examples represents an omnibus of best practice methods offered by biostatistical practitioners inside and outside of industry. The article presents a protocol template for clinical research design, enabling statisticians, from beginners to advanced.

17.
Trials ; 21(1): 579, 2020 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-32586393

RESUMEN

BACKGROUND: Multiple therapies exist for patients with metastatic castration-resistant prostate cancer (mCRPC). However, their improvement on progression-free survival (PFS) remains modest, potentially explained by tumor molecular heterogeneity. Several prognostic molecular biomarkers have been identified for mCRPC that may have predictive potential to guide treatment selection and prolong PFS. We designed a platform trial to test this hypothesis. METHODS: The Prostate-Biomarker (ProBio) study is a multi-center, outcome-adaptive, multi-arm, biomarker-driven platform trial for tailoring treatment decisions for men with mCRPC. Treatment decisions in the experimental arms are based on biomarker signatures defined as mutations in certain genes/pathways suggested in the scientific literature to be important for treatment response in mCRPC. The biomarker signatures are determined by targeted sequencing of circulating tumor and germline DNA using a panel specifically designed for mCRPC. DISCUSSION: Patients are stratified based on the sequencing results and randomized to either current clinical practice (control), where the treating physician decides treatment, or to molecularly driven treatment selection based on the biomarker profile. Outcome-adaptive randomization is implemented to early identify promising treatments for a biomarker signature. Biomarker signature-treatment combinations graduate from the platform when they demonstrate 85% probability of improving PFS compared to the control arm. Graduated combinations are further evaluated in a seamless confirmatory trial with fixed randomization. The platform design allows for new drugs and biomarkers to be introduced in the study. CONCLUSIONS: The ProBio design allows promising treatment-biomarker combinations to quickly graduate from the platform and be confirmed for rapid implementation in clinical care. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT03903835. Date of registration: April 4, 2019. Status: Recruiting.


Asunto(s)
Biomarcadores de Tumor/genética , Medicina de Precisión , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/terapia , Ensayos Clínicos Fase III como Asunto , Análisis Mutacional de ADN , Mutación de Línea Germinal , Humanos , Masculino , Estudios Multicéntricos como Asunto , Metástasis de la Neoplasia , Supervivencia sin Progresión , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
18.
Am J Gastroenterol ; 103(9): 2181-3, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18671812

RESUMEN

Scientific and medical authors tend to be biased toward submitting "statistically significant" findings for publication. Journals show a similar bias in publishing such "positive" studies. The large number of publications in medical research means that, in a field obsessed with controlling Type I error rates, we have journals with an abundance of Type I errors. Failing to publish studies that do not show a treatment or exposure effect creates a literature conspicuously absent of trials necessary for unbiased meta-analyses and systematic reviews. Furthermore, by shelving or rejecting studies with nonstatistically significant outcomes, authors and editors censor the most important contributors to medical research: our consenting volunteers.


Asunto(s)
Ensayos Clínicos como Asunto/estadística & datos numéricos , Sesgo de Publicación , Edición , Investigación Biomédica , Enfermedad de Crohn/tratamiento farmacológico , Interpretación Estadística de Datos , Everolimus , Humanos , Inmunosupresores/uso terapéutico , Edición/ética , Sirolimus/análogos & derivados , Sirolimus/uso terapéutico , Insuficiencia del Tratamiento
19.
Am J Gastroenterol ; 103(7): 1698-706, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18494835

RESUMEN

OBJECTIVE: We investigated patterns of use of alcohol and its clinical effects among cirrhotic subjects who participated in a randomized clinical trial comparing the efficacy of transjugular intravenous portosystemic shunt and distal splenorenal shunt. METHODS: There were 132 cirrhotic subjects, 78 with alcoholic liver disease (ALD), who were followed for a median of 49 months (range 2-93 months). Alcohol use was assessed by patient questionnaire, with corroboration by family members. RESULTS: Twenty-eight subjects (21%) were drinking at study entry and 60 subjects (45%) drank during follow-up. Heavy drinking (>4 drinks/day) was recorded in 25 ALD subjects, but in no non-ALD subjects (P < 0.0001). Drinking by ALD subjects was associated with a 153% increase in gamma-glutamyl transpeptidase (GGT) (P < 0.0001). The frequencies of death (46%vs 30%), ascites (33%vs 20%), encephalopathy (56%vs 42%), and variceal bleeding (11%vs 3%) were greater in the ALD group. In a Cox proportional hazards model only "ever heavy drinking" was associated with death (P= 0.0099), while recent heavy drinking increased the hazard of variceal hemorrhage dramatically (odds ratio 10.85). CONCLUSIONS: Whereas most cirrhotic subjects, alcoholic or not, did not drink during 5 yr of observation, heavy alcohol use occurred exclusively in ALD patients. Alcohol use by ALD subjects was associated with elevations in GGT and was linked to death and with rebleeding from shunt dysfunction.


Asunto(s)
Consumo de Bebidas Alcohólicas , Cirrosis Hepática Alcohólica/fisiopatología , Consumo de Bebidas Alcohólicas/mortalidad , Ascitis/etiología , Várices Esofágicas y Gástricas/complicaciones , Femenino , Estudios de Seguimiento , Hemorragia Gastrointestinal/complicaciones , Encefalopatía Hepática/etiología , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/enzimología , Cirrosis Hepática/mortalidad , Cirrosis Hepática/fisiopatología , Cirrosis Hepática Alcohólica/enzimología , Cirrosis Hepática Alcohólica/mortalidad , Hepatopatías Alcohólicas/fisiopatología , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , gamma-Glutamiltransferasa/sangre
20.
JNCI Cancer Spectr ; 2(4): pky067, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31360882

RESUMEN

BACKGROUND: WISDOM (Women Informed to Screen Depending on Measures of Risk) is a randomized trial to assess whether personalized breast cancer screening-where women are screened biannually, annually, biennially, or not at all depending on risk and age-can prevent as many advanced (stage IIB or higher) cancers as annual screening in women ages 40-74 years across 5 years of trial time. The short study time in combination with design choices of not requiring study entry and exit mammograms for all participants may introduce different sources of bias in favor of either the personalized or the annual arm. METHODS: We designed a simulation model and performed 5000 virtual WISDOM trials to assess potential biases. Each virtual trial simulated 65 000 randomly assigned participants who were each assigned a risk stratum and a time to stage of at least IIB cancer sampled from an exponential distribution with the hazard rate based on the risk stratum. Results from the virtual trials were used to evaluate two candidate analysis strategies with respect to susceptibility for introducing bias: 1) difference between arms in total number of events over total trial time, and 2) difference in number of events within complete screening cycles. RESULTS: Based on the simulations, about 86 stage IIB or higher cancers will be detected within the trial and the total exposure time will be about 74 000 years in each arm. Potential ascertainment bias is introduced at study entry and exit. Analysis strategy 1 works better for the nonscreened stratum, whereas method 2 is considerably more unbiased for the strata of women screened biennially or every 6 months. CONCLUSION: Combining the two candidate analysis approaches gives a reasonably unbiased analysis based on the simulations and is the method we will use for the primary analysis in WISDOM. Publishing the WISDOM analysis approach provides transparency and can aid the design and analysis of other individualized screening trials.

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