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1.
PLoS One ; 17(1): e0262114, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35061758

RESUMO

BACKGROUND: Early in the SARS-CoV-2 pandemic, commentators warned that some COVID trials were inadequately conceived, designed and reported. Here, we retrospectively assess the prevalence of informative COVID trials launched in the first 6 months of the pandemic. METHODS: Based on prespecified eligibility criteria, we created a cohort of Phase 1/2, Phase 2, Phase 2/3 and Phase 3 SARS-CoV-2 treatment and prevention efficacy trials that were initiated from 2020-01-01 to 2020-06-30 using ClinicalTrials.gov registration records. We excluded trials evaluating behavioural interventions and natural products, which are not regulated by the U.S. Food and Drug Administration (FDA). We evaluated trials on 3 criteria of informativeness: potential redundancy (comparing trial phase, type, patient-participant characteristics, treatment regimen, comparator arms and primary outcome), trials design (according to the recommendations set-out in the May 2020 FDA guidance document on SARS-CoV-2 treatment and prevention trials) and feasibility of patient-participant recruitment (based on timeliness and success of recruitment). RESULTS: We included all 500 eligible trials in our cohort, 58% of which were Phase 2 and 84.8% were directed towards the treatment of SARS-CoV-2. Close to one third of trials met all three criteria and were deemed informative (29.9% (95% Confidence Interval 23.7-36.9)). The proportion of potentially redundant trials in our cohort was 4.1%. Over half of the trials in our cohort (56.2%) did not meet our criteria for high quality trial design. The proportion of trials with infeasible patient-participant recruitment was 22.6%. CONCLUSIONS: Less than one third of COVID-19 trials registered on ClinicalTrials.gov during the first six months met all three criteria for informativeness. Shortcomings in trial design, recruitment feasibility and redundancy reflect longstanding weaknesses in the clinical research enterprise that were likely amplified by the exceptional circumstances of a pandemic.


Assuntos
Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , COVID-19/epidemiologia , Projetos de Pesquisa/estatística & dados numéricos , SARS-CoV-2/efeitos dos fármacos , COVID-19/prevenção & controle , COVID-19/virologia , Ensaios Clínicos Fase I como Assunto/ética , Ensaios Clínicos Fase II como Assunto/ética , Ensaios Clínicos Fase III como Assunto/ética , Humanos , Seleção de Pacientes/ética , Guias de Prática Clínica como Assunto , SARS-CoV-2/patogenicidade
6.
Pharm Stat ; 19(3): 178-186, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31729173

RESUMO

The large number of failures in phase III clinical trials, which occur at a rate of approximately 45%, is studied herein relative to possible countermeasures. First, the phenomenon of failures is numerically described. Second, the main reasons for failures are reported, together with some generic improvements suggested in the related literature. This study shows how statistics explain, but do not justify, the high failure rate observed. The rate of failures due to a lack of efficacy that are not expected, is considered to be at least 10%. Expanding phase II is the simplest and most intuitive way to reduce phase III failures since it can reduce phase III false negative findings and launches of phase III trials when the treatment is positive but suboptimal. Moreover, phase II enlargement is discussed using an economic profile. As resources for research are often limited, enlarging phase II should be evaluated on a case-by-case basis. Alternative strategies, such as biomarker-based enrichments and adaptive designs, may aid in reducing failures. However, these strategies also have very low application rates with little likelihood of rapid growth.


Assuntos
Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Determinação de Ponto Final , Projetos de Pesquisa , Ensaios Clínicos Fase II como Assunto/economia , Ensaios Clínicos Fase II como Assunto/ética , Ensaios Clínicos Fase II como Assunto/estatística & dados numéricos , Ensaios Clínicos Fase III como Assunto/economia , Ensaios Clínicos Fase III como Assunto/ética , Ensaios Clínicos Fase III como Assunto/estatística & dados numéricos , Interpretação Estatística de Dados , Determinação de Ponto Final/economia , Determinação de Ponto Final/ética , Determinação de Ponto Final/estatística & dados numéricos , Humanos , Modelos Estatísticos , Projetos de Pesquisa/estatística & dados numéricos , Falha de Tratamento
7.
Cancer Treat Rev ; 74: 15-20, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30665053

RESUMO

Progress in and better understanding of cancer biology causes a shift in cancer drug development: away from the evaluation of drugs in large tumour histology defined patient populations towards targeted agents in increasingly heterogeneous molecularly defined subpopulations. This requires novel approaches in clinical trial design by academia and industry, and development of new assessment tools by regulatory authorities. Pharmaceutical industry is developing new targeted agents generating many clinical studies, including target combinations. This requires improved operational efficiency by development of innovative trial designs, strategies for early-stage decision making and early selection of candidate drugs with a high likelihood of success. In addition, patient awareness and ethical considerations necessitate that agents will be rapidly available to patients. Regulatory Authorities such as the European Medicine Agency and national agencies recognise that these changes require a different attitude towards benefit-risk analysis for drug approval. The gold standard of randomised confirmatory Phase III trials is not always ethical or feasible when developing drugs for treatment of small cancer populations. Alternative strategies comprise accelerated approval via conditional marketing approval, which can be granted in the EU based on small non-randomised Phase II trials. The paper describes innovative trial designs with their pros and cons and efforts of pharmaceutical industry and regulatory authorities to deal with the paradigm shift. Furthermore, all stakeholders should continue to share their experiences and discuss problems in order to understand the position and concerns of the other stakeholders to learn from each other and to progress the field of novel oncology clinical trial design.


Assuntos
Ensaios Clínicos como Assunto/métodos , Antineoplásicos , Ensaios Clínicos como Assunto/ética , Ensaios Clínicos como Assunto/normas , Ensaios Clínicos Fase I como Assunto/ética , Ensaios Clínicos Fase I como Assunto/métodos , Ensaios Clínicos Fase I como Assunto/normas , Ensaios Clínicos Fase II como Assunto/ética , Ensaios Clínicos Fase II como Assunto/métodos , Ensaios Clínicos Fase II como Assunto/normas , Ensaios Clínicos Fase III como Assunto/ética , Ensaios Clínicos Fase III como Assunto/métodos , Ensaios Clínicos Fase III como Assunto/normas , Desenvolvimento de Medicamentos , Humanos , Oncologia/ética , Oncologia/métodos , Oncologia/normas , Terapia de Alvo Molecular , Ensaios Clínicos Controlados Aleatórios como Assunto/ética , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/normas
8.
Biom J ; 60(6): 1121-1134, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30209817

RESUMO

A quantitative evaluation of individual and collective ethics is proposed here, with the aim of providing a tool for sample size determination/estimation that goes further than the standard power setting of 80-90%. Individual ethics deal with issues that concern the patients enrolled in the trial, where collective ones concern the patients not enrolled in the trial, and who might benefit from a positive result. The global ethical utility (GEU) of a phase III trial is introduced here, being the summation of individual and collective ethical utilities, and can be viewed as a function of the sample size. The GEU model is based on the extent of the efficacy of the treatments in study, of the quality of life of the patients being treated, of the effects of potential adverse reactions, it accounts for the duration of the periods of interest and for the size of population groups, and also embeds the experimental power. This work aims at arguing the case for GEU adoption for sample size determination. The sample size that maximizes GEU can be adopted for planning the trial, even when providing a power value out of the classical range [.8,.9]. Alternatively, among the sample sizes based on power values of 80% and 90%, the one providing the highest GEU can be adopted. Intuitively, when a treatment is assumed to work well, to have few adverse effects, and is expected to improve the QoL of the ill population for a considerable amount of time, collective ethics may prevail giving ethically optimal sample sizes larger than usual, and consequent quite high power values (e.g. 99%). Instead, medium, though still clinically meaningful, levels of effect, considerable adverse reactions, and limited life expectation and QoL improvement, might shift the ethical balance on individual ethics and give an ethically optimal sample size providing a power lower than standard values (e.g. 70%). Some examples and an application in the cardiovascular area, including sensitivity analyses of the results based on the so-called Bayesian "assurance" technique, are also discussed. Several possible extensions of the model related to particular clinical frameworks are also presented.


Assuntos
Biometria/métodos , Ensaios Clínicos Fase III como Assunto/ética , Humanos , Modelos Estatísticos , Tamanho da Amostra
10.
Regen Med ; 12(6): 599-609, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28976818

RESUMO

Harmonized regulation of research with human stem cells in Europe has shaped innovation in regenerative medicine. Findings from a Phase III academic clinical trial of an autologous cell procedure illustrate the obstacles that a multinational trial faces. A typology of the obstacles encountered, may help other teams embarking upon trials. The findings throw light on the situation of clinician-scientists in clinical innovation, as the expertise to run scientific trials is very complex. The innovation route of clinical translation takes insufficient account of the interdependencies between multiple social and cultural factors from outside the laboratory and the clinic. For ethical reasons, however, academic and business routes to stem cell treatments ought to be enabled by the regulators. Suggestions arise, how academics can prepare for trials, that academic research needs better institutional support and that new models of medical innovation may need to be developed for regenerative medicine.


Assuntos
Ensaios Clínicos Fase III como Assunto/métodos , Medicina Regenerativa/tendências , Pesquisa com Células-Tronco , Ensaios Clínicos Fase III como Assunto/economia , Ensaios Clínicos Fase III como Assunto/ética , Europa (Continente) , Humanos , Medicina Regenerativa/ética , Medicina Regenerativa/métodos , Controle Social Formal
11.
J Clin Epidemiol ; 91: 87-94, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28757260

RESUMO

OBJECTIVES: The decision to make protocols of phase III randomized controlled trials (RCTs) publicly accessible by leading journals was a landmark event in clinical trial reporting. Here, we compared primary outcomes defined in protocols with those in publications describing the trials and in trial registration. STUDY DESIGN AND SETTING: We identified phase III RCTs published between January 1, 2012, and June 30, 2015, in The New England Journal of Medicine, The Lancet, The Journal of the American Medical Association, and The BMJ with available protocols. Consistency in primary outcomes between protocols and registries (articles) was evaluated. RESULTS: We identified 299 phase III RCTs with available protocols in this analysis. Out of them, 25 trials (8.4%) had some discrepancy for primary outcomes between publications and protocols. Types of discrepancies included protocol-defined primary outcome reported as nonprimary outcome in publication (11 trials, 3.7%), protocol-defined primary outcome omitted in publication (10 trials, 3.3%), new primary outcome introduced in publication (8 trials, 2.7%), protocol-defined nonprimary outcome reported as primary outcome in publication (4 trials, 1.3%), and different timing of assessment of primary outcome (4 trials, 1.3%). Out of trials with discrepancies in primary outcome, 15 trials (60.0%) had discrepancies that favored statistically significant results. Registration could be seen as a valid surrogate of protocol in 237 of 299 trials (79.3%) with regard to primary outcome. CONCLUSION: Despite unrestricted public access to protocols, selective outcome reporting persists in a small fraction of phase III RCTs. Only studies from four leading journals were included, which may cause selection bias and limit the generalizability of this finding.


Assuntos
Ensaios Clínicos Fase III como Assunto/ética , Viés de Publicação , Publicações/ética , Ensaios Clínicos Controlados Aleatórios como Assunto/ética , Sistema de Registros/ética , Humanos , Disseminação de Informação/ética , Avaliação de Resultados da Assistência ao Paciente , Relatório de Pesquisa
14.
Salud Colect ; 11(1): 99-114, 2015 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-25853833

RESUMO

In 2008, Brazil's Federal Council of Medicine [Conselho Federal de Medicina] (CFM)--regulatory and supervisory agency on the ethical practice of medicine--banned the participation of Brazilian doctors in studies using placebos for diseases with efficient and effective treatment. This position differs with the Helsinki Declaration, which allows the use of placebos in methodologically justified conditions. To ascertain whether the CMF's ethical regulation modified the use of placebos in phase III clinical trials in Brazil, characteristics of the records in ClinicalTrials.gov were researched in the periods from 2003 to 2007 and from 2009 to 2013. The conclusions reached were: a) the regulations issued by the CFM in 2008 were ineffective and the position adopted by the Helsinki Declaration prevails; b) there was significant sponsorship by the multinational pharmaceutical industry of trials with placebos; c) the research was predominantly on new drugs for chronic diseases, with little study done of the neglected diseases which are of great importance to Brazil.


Assuntos
Ensaios Clínicos Fase III como Assunto/ética , Placebos , Brasil , Ensaios Clínicos Fase III como Assunto/economia , Ensaios Clínicos Fase III como Assunto/métodos , Ensaios Clínicos Fase III como Assunto/estatística & dados numéricos , Indústria Farmacêutica/ética , Declaração de Helsinki , Humanos , Apoio à Pesquisa como Assunto/ética
16.
Stat Med ; 33(29): 5041-56, 2014 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-25224560

RESUMO

In phase 3 clinical trials, ethical and financial concerns motivate sequential analyses in which the data are analyzed prior to completion of the entire planned study. Existing group sequential software accounts for the effects of these interim analyses on the sampling density by assuming that the contribution of subsequent increments is independent of the contribution from previous data. This independent increment assumption is satisfied in many common circumstances, including when using the efficient estimator. However, certain circumstances may dictate using an inefficient estimator, and the independent increment assumption may then be violated. Consequences of assuming independent increments in a setting where the assumption does not hold have not been previously explored. One important setting in which independent increments may not hold is the setting of longitudinal clinical trials. This paper considers dependent increments that arise because of heteroscedastic and correlated data in the context of longitudinal clinical trials that use a generalized estimating equation (GEE) approach. Both heteroscedasticity over time and correlation of observations within subjects may lead to departures from the independent increment assumption when using GEE. We characterize situations leading to greater departures in this paper. Despite violations of the independent increment assumption, simulation results suggest that operating characteristics of sequential designs are largely maintained for typically observed patterns of accrual, correlation, and heteroscedasticity even when using analyses that use standard software that depends on an independent increment structure. More extreme scenarios may require greater care to avoid departures from the nominal type I error rate and power.


Assuntos
Ensaios Clínicos Fase III como Assunto/estatística & dados numéricos , Projetos de Pesquisa Epidemiológica , Estudos Longitudinais , Ensaios Clínicos Fase III como Assunto/economia , Ensaios Clínicos Fase III como Assunto/ética , Humanos , Estatística como Assunto/métodos
17.
Oncologist ; 19(10): 1069-75, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25170014

RESUMO

INTRODUCTION: Cancer societies, research cooperatives, and countless publications have urged the development of clinical trials that facilitate the inclusion of older patients and those with comorbidities. We set out to determine the characteristics of currently recruiting clinical trials with hematological patients to assess their inclusion and exclusion of elderly patients. METHODS: The NIH clinical trial registry was searched on July 1, 2013, for currently recruiting phase I, II or III clinical trials with hematological malignancies. Trial characteristics and study objectives were extracted from the registry website. RESULTS: Although 5% of 1,207 included trials focused exclusively on elderly or unfit patients, 69% explicitly or implicitly excluded older patients. Exclusion based on age was seen in 27% of trials, exclusion based on performance status was seen in 16%, and exclusion based on stringent organ function restrictions was noted in 51%. One-third of the studies that excluded older patients based on age allowed inclusion of younger patients with poor performance status; 8% did not place any restrictions on organ function. Over time, there was a shift from exclusion based on age (p value for trend <.001) toward exclusion based on organ function (p = .2). Industry-sponsored studies were least likely to exclude older patients (p < .001). CONCLUSION: Notably, 27% of currently recruiting clinical trials for hematological malignancies use age-based exclusion criteria. Although physiological reserves diminish with age, the heterogeneity of the elderly population does not legitimize exclusion based on chronological age alone. Investigators should critically review whether sufficient justification exists for every exclusion criterion before incorporating it in trial protocols.


Assuntos
Ensaios Clínicos como Assunto , Neoplasias Hematológicas/terapia , Seleção de Pacientes , Idoso , Idoso de 80 Anos ou mais , Etarismo/ética , Etarismo/estatística & dados numéricos , Ensaios Clínicos Fase I como Assunto/ética , Ensaios Clínicos Fase I como Assunto/métodos , Ensaios Clínicos Fase II como Assunto/ética , Ensaios Clínicos Fase II como Assunto/métodos , Ensaios Clínicos Fase III como Assunto/ética , Ensaios Clínicos Fase III como Assunto/métodos , Humanos , Avaliação de Estado de Karnofsky/normas , Escores de Disfunção Orgânica , Sistema de Registros
18.
Kennedy Inst Ethics J ; 24(2): 121-39, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25109092

RESUMO

Should first-in-human trials be designed to maximize the prospect of therapeutic benefit for volunteers, prioritize avoidance of unintended harms, or aim for some happy medium between the two? Perennial controversies surrounding initiation and design of early-phase trials hinge on how this question is resolved. In this paper, we build on the premise that the task of early-phase testing is to optimize various components of a potential therapy so that later, confirmatory trials have the maximal probability of informing drug development and clinical care. We then explore three strategies that investigators might use to manage trial risks while optimizing a therapy, using cell therapy for Amyotrophic Lateral Sclerosis (ALS) as an example. We argue that an iterative application of maximin strategies over successive cohorts and trials, which we call the "risk-escalation model," establishes a moral principle that should guide decision-making in early-phase trials.


Assuntos
Ensaios Clínicos como Assunto/ética , Seleção de Pacientes/ética , Projetos de Pesquisa , Medição de Risco/ética , Experimentação Humana Terapêutica/ética , Esclerose Lateral Amiotrófica/terapia , Terapia Baseada em Transplante de Células e Tecidos/efeitos adversos , Terapia Baseada em Transplante de Células e Tecidos/ética , Ensaios Clínicos Fase II como Assunto/ética , Ensaios Clínicos Fase III como Assunto/ética , Tomada de Decisões/ética , Humanos , Projetos de Pesquisa/normas , Projetos de Pesquisa/tendências , Medição de Risco/normas , Resultado do Tratamento , Incerteza
19.
World J Surg ; 38(10): 2487-93, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24824646

RESUMO

BACKGROUND: Discussions regarding disclosure of funding sources and conflicts of interest (COI) in published peer-reviewed journal articles are becoming increasingly more common and intense. The aim of the present study was to examine whether randomized controlled trials (RCTs) published in leading surgery journals report funding sources and COI. METHODS: All articles reporting randomized controlled phase III trials published January 2005 through December 2010 were chosen for review from ten international journals. We evaluated the number of disclosed funding sources and COI, and the factors associated with such disclosures. RESULTS: From a review of 657 RCT from the ten journals, we discovered that presence or absence of a funding source and COI was disclosed by 47 % (309) and 25.1 % (165), respectively. Most articles in "International Committee of Medical Journal Editors (ICMJE)-affiliated journals" did not disclose COI. Disclosure of funding was associated with a journal impact factor >3 (51.7 vs 41.6 %; p < 0.01), statistician/epidemiologist involvement (64.2 vs 43.7 %; p < 0.001), publication after 2008 (52.9 vs 41.1 %; p < 0.01), and the journal being ICMJE-affiliated (49.3 vs 40 %; p < 0.05). Conflict of interest disclosure was associated with publication after 2008 (38.7 vs 11.3 %; p < 0.001), and with the journal not being affiliated with ICMJE (36.9 vs 21.3 %; p < 0.001). CONCLUSIONS: Of the published studies we investigated, over half did not disclose funding sources (i.e., whether or not there was a funding source), and almost three quarters did not disclose whether COI existed. Our findings suggest the need to adopt best current practices regarding disclosure of competing interests to fulfill responsibilities to readers and, ultimately, to patients.


Assuntos
Ensaios Clínicos Fase III como Assunto/economia , Conflito de Interesses , Revelação , Cirurgia Geral , Publicações Periódicas como Assunto/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/economia , Apoio à Pesquisa como Assunto , Ensaios Clínicos Fase III como Assunto/ética , Políticas Editoriais , Humanos , Fator de Impacto de Revistas , Publicações Periódicas como Assunto/normas , Ensaios Clínicos Controlados Aleatórios como Assunto/ética , Fatores de Tempo
20.
Stat Med ; 33(23): 4043-52, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24849843

RESUMO

It is well known that competing demands exist between the control of important covariate imbalance and protection of treatment allocation randomness in confirmative clinical trials. When implementing a response-adaptive randomization algorithm in confirmative clinical trials designed under a frequentist framework, additional competing demands emerge between the shift of the treatment allocation ratio and the preservation of the power. Based on a large multicenter phase III stroke trial, we present a patient randomization scheme that manages these competing demands by applying a newly developed minimal sufficient balancing design for baseline covariates and a cap on the treatment allocation ratio shift in order to protect the allocation randomness and the power. Statistical properties of this randomization plan are studied by computer simulation. Trial operation characteristics, such as patient enrollment rate and primary outcome response delay, are also incorporated into the randomization plan.


Assuntos
Ensaios Clínicos Fase III como Assunto/métodos , Estudos Multicêntricos como Assunto/métodos , Seleção de Pacientes/ética , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Acidente Vascular Cerebral/terapia , Teorema de Bayes , Distribuição de Qui-Quadrado , Ensaios Clínicos Fase III como Assunto/economia , Ensaios Clínicos Fase III como Assunto/ética , Simulação por Computador , Humanos , Estudos Multicêntricos como Assunto/ética , Ensaios Clínicos Controlados Aleatórios como Assunto/economia , Ensaios Clínicos Controlados Aleatórios como Assunto/ética
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