28 research outputs found

    Recruitment failure and futility were the most common reasons for discontinuation of clinical drug trials. Results of a nationwide inception cohort study in the Netherlands

    Get PDF
    Objectives The objective of the study was to identify the reasons for discontinuation of clinical drug trials and to evaluate whether efficacy-related discontinuations were adequately planned in the trial protocol. Study Design and Setting All clinical drug trials in the Netherlands, reviewed by institutional review boards in 2007, were followed until December 2015. Data were obtained through the database of the Dutch competent authority (Central Committee on Research Involving Human Subjects [CCMO]) and a questionnaire to the principal investigators. Reasons for trial discontinuation were the primary outcome of the study. Three reasons for discontinuation were analyzed separately: all cause, recruitment failure, and efficacy related (when an interim analysis had demonstrated futility or superiority). Among the efficacy-related discontinuations, we examined whether the data monitoring committee, the stopping rule, and the moment of the interim analysis in the trial progress were specified in the trial protocol. Results Of the 574 trials, 102 (17.8%) were discontinued. The most common reasons were recruitment failure (33 of 574; 5.7%) and solely efficacy related (30 of 574; 5.2%). Of the efficacy-related discontinuations, 10 of 30 (33.3%) of the trial protocols reported all three aspects in the trial protocol, and 20 of 30 (66.7%) reported at least one aspect in the trial protocol. Conclusion One out of five clinical drug trials is discontinued before the planned trial end, with recruitment failure and futility as the most common reasons. The target sample size of trials should be feasible, and interim analyses should be adequately described in trial protocols

    Biogenesis and Dynamics of Mitochondria during the Cell Cycle: Significance of 3′UTRs

    Get PDF
    Nowadays, we are facing a renaissance of mitochondria in cancer biology. However, our knowledge of the basic cell biology and on the timing and mechanisms that control the biosynthesis of mitochondrial constituents during progression through the cell cycle of mammalian cells remain largely unknown. Herein, we document the in vivo changes on mitochondrial morphology and dynamics that accompany cellular mitosis, and illustrate the following key points of the biogenesis of mitochondria during progression of liver cells through the cycle: (i) the replication of nuclear and mitochondrial genomes is synchronized during cellular proliferation, (ii) the accretion of OXPHOS proteins is asynchronously regulated during proliferation being the synthesis of β-F1-ATPase and Hsp60 carried out also at G2/M and, (iii) the biosynthesis of cardiolipin is achieved during the S phase, although full development of the mitochondrial membrane potential (ΔΨm) is attained at G2/M. Furthermore, we demonstrate using reporter constructs that the mechanism regulating the accretion of β-F1-ATPase during cellular proliferation is controlled at the level of mRNA translation by the 3′UTR of the transcript. The 3′UTR-driven synthesis of the protein at G2/M is essential for conferring to the daughter cells the original phenotype of the parental cell. Our findings suggest that alterations on this process may promote deregulated β-F1-ATPase expression in human cancer

    Causes of reporting bias: a theoretical framework

    Get PDF
    Reporting of research findings is often selective. This threatens the validity of the published body of knowledge if the decision to report depends on the nature of the results. The evidence derived from studies on causes and mechanisms underlying selective reporting may help to avoid or reduce reporting bias. Such research should be guided by a theoretical framework of possible causal pathways that lead to reporting bias. We build upon a classification of determinants of selective reporting that we recently developed in a systematic review of the topic. The resulting theoretical framework features four clusters of causes. There are two clusters of necessary causes: (A) motivations (e.g. a preference for particular findings) and (B) means (e.g. a flexible study design). These two combined represent a sufficient cause for reporting bias to occur. The framework also features two clusters of component causes: (C) conflicts and balancing of interests referring to the individual or the team, and (D) pressures from science and society. The component causes may modify the effect of the necessary causes or may lead to reporting bias mediated through the necessary causes. Our theoretical framework is meant to inspire further research and to create awareness among researchers and end-users of research about reporting bias and its causes

    Screening Questions for Nonsteroidal Anti-inflammatory Drug Risk Knowledge

    No full text
    OBJECTIVE: The aim of this study was to evaluate screening questions for estimating nonsteroidal anti-inflammatory drug (NSAID) risk knowledge. METHODS: Cross-sectional data from a telephone interview of NSAID users 50 years or older from 39 physician practices in Alabama were used. Patient-reported awareness of prescription NSAID risk and health literacy were the independent variables, and a cumulative index score of objectively tested knowledge of 4 prominent NSAID risks was the dependent variable. General linearized latent and mixed model ordered logistic regression was used to estimate associations among the independent variables, covariates, and objectively tested NSAID risk knowledge. Population-averaged probabilities for levels of objectively tested NSAID risk knowledge were subsequently estimated. RESULTS: Subjective awareness of any prescription NSAID risk (adjusted odds ratio [AOR], 2.40; 95% confidence interval [CI], 1.55-3.74), adequate health literacy (AOR, 1.71; 95% CI, 1.04-2.83), and physician counseling about 1 or more NSAID risks (AOR, 1.69; 95% CI, 1.09-2.61) were significantly and positively associated with NSAID risk knowledge. The probability of correctly answering at least 1 of the 4 NSAID risk knowledge questions was 70% in the absence of any subjective risk awareness and in less than adequate health literacy. Whereas the probability of correctly answering at least 1 of the 4 NSAID risk knowledge questions increased to 86% in the presence of subjective awareness of any prescription NSAID risk and adequate health literacy. CONCLUSIONS: Screening questions for subjective NSAID risk awareness and health literacy are predictive of objectively tested NSAID knowledge and can be used to triage patients as well as subsequently initiate and direct a conversation about NSAID risk

    Publication rates and reported results in a cohort of gene- and cell-based therapy trials

    Get PDF
    Aim: We investigated publication rates and reported results for gene- and cell-based therapy trials. Materials & methods: In a cohort of Institutional Review Board (IRB)-authorized trials during 2007-2017 in the Netherlands (n = 105), we examine publication rates and reported results in scientific papers and conference abstracts as well as associations with the occurrence of trial characteristics. Results: The publication rate for scientific papers was 27% and 17% for conference abstracts (median survival time: 1050 days). Academic hospitals published more in scientific papers whereas private sponsors published more in conference abstracts. Manufacturing protocols were underreported compared with clinical outcomes. Most publications reported positive results (78%). Conclusion: Publication rates are currently suboptimal indicating a need for enhanced knowledge sharing to stimulate gene- and cell-based therapy development
    corecore