Design and Analysis Considerations in Clinical Trials With a Sensitive Subpopulation

This article deals with clinical trials with a sensitive subpopulation of patients, that is, a subgroup that is more likely to benefit from the treatment than the overall population. Given a sensitive subgroup defined by a prespecified classifier, for example, a clinical marker or pharmacogenomic marker, the trial’s outcome is declared positive if the treatment effect is established in the overall population or in the subgroup. We provide a summary of key considerations in clinical trials with a sensitive subgroup, including multiplicity and enrichment adjustments as well as optimality considerations in the analysis strategy. The methodology proposed in this article is illustrated using a neuroscience clinical trial and its operating characteristics are assessed via a simulation study.     

Testing Treatment Effect in Randomized Clinical Trials With Possible Nonproportional Hazards

The Cox model is the recognized industry standard when designing and analyzing randomized clinical trials with right-censored data. As the model is based on the proportional hazards (PH) assumption, if the hazard ratio changes over time, as often occurs during long-term studies, the interpretation of the Cox hazard ratio becomes problematic. Furthermore, the Cox model is not powerful in the event of crossing hazards. Here, we consider a range of tests to compare two treatment groups in randomized clinical trials where the PH assumption is in doubt. The proposed methods are evaluated on simulated data and compared using data from a cancer clinical trial.     

中国临床试验注册中心在册药物临床试验分析

目的:了解中国临床试验注册中心(ChiCTR)在册的药物临床试验的现状和特点。方法:检索ChiCTR数据库(截至2011年11月9日),记录相应药物临床试验并从目标疾病、地域分布、经费来源、研究类型、研究设计等方面进行分析。结果与结论:在ChiCTR注册的药物临床试验共714项,以治疗恶性肿瘤(27.9%)、循环系统疾病(13.0%)等的研究为主;经费主要来源于研究者及所在单位、制药企业和国家财政3个方面;多为单中心、治疗性试验;研究地点集中在北京市、上海市、广东省和四川省等地;Ⅳ期临床试验411项(57.6%),Ⅰ、Ⅱ、Ⅲ期及临床预试验比例都在10%左右;明确应用盲法的随机对照试验占45.1%。     

药师作为临床研究协调员在新药临床试验中的作用

目的：为保证新药临床试验的安全性及客观性提供参考。方法：总结并分析药师参与临床试验的优势与必要性,介绍了药师参与药物临床试验的实践经验,包括医院临床试验制度的建立与流程管理、法规培训与宣传、不良事件记录与评估、药品管理与用药教育、质量监查等。结果与结论：药师全程参与临床试验的实施与管理,进一步确保了新药临床试验的安全性及客观性,促进了医院临床试验的有效管理,提高了临床试验的质量。     

Noninferiority Trials in Regulatory Guidance and Marketing Authorization Applications: Huge Advances Over the Last 20 Years but Problems Still to be Solved

The analysis of noninferiority trials in marketing authorization applications has advanced greatly over the last 20 years, moving from an approach where failing to detect a statistically significant difference led to concluding that there was no difference to the current confidence-interval-based methods. This article follows the changes with reference to regulatory guidance issued across this period while touching on some of the regularly recurring debates surrounding analysis populations and coverage probabilities. The complex issue of how to define the noninferiority margin is addressed, including discussion of whether a margin exists in all situations and the implications this has for the entire noninferiority framework.     

注册于中国临床试验注册中心的儿科药物临床试验项目特征分析

目的:为规范我国儿科药物临床试验项目开展、促进儿科人群用药的开发与应用提供参考。方法:检索中国临床试验注册中心(Chi CTR)数据库,收集所有研究对象年龄<18周岁的药物临床试验项目,检索时限从建库起至2019年10月1日,对其项目名称、研究所涉疾病/系统、研究所处阶段、注册时间、注册状态、研究负责单位地域分布、经费来源、研究类型、是否设置数据管理委员会、征募研究对象情况、伦理委员会批准情况、是否采用盲法、是否采集人体标本及人体标本去向等信息进行统计分析。结果:共收集到儿科药物临床试验231项,共涉及21个类别的系统/疾病,包括肿瘤及瘤样病变、眼科疾病、变态反应性疾病等;研究所处阶段以上市后药物临床试验的项目有85项(占36.80%),Ⅰ～Ⅳ期药物临床试验共有77项(占33.33%);注册项目数量逐年增加,有179项(77.49%)为预注册,52项(22.51%)为补注册;注册项目较多的前5位地区分别为北京、上海、广东、重庆、浙江,其项目数共占纳入项目总数的66.23%(153/231);经费来源主要为自筹(57.85%)、医院资助(20.18%)、地方财政资金(10.31%)...     

Clinical Trials Do Not Use Random Samples Anymore

Current clinical trials do not use random samples, but, instead, convenience samples. This raises the risk of non-normal data.

The aim of this paper is to review and describe for a non-mathematical readership common methods for testing the normal property, as well as methods for analyzing the data in case of non-normality.

With slight departures from the normal distribution, normality tests can be used even so. They include, among other tests, the normal-, t-, chi-square- tests, analysis of variance, and regression analyses. They should not be used if the chi-square goodness of fit is significant. Rank-testing is, then, an alternative, but, sometimes, distributions do not allow for this approach either. This can be checked by the Kolmogorov-Smirnov test. If the latter test is also positive, rank-testing is not warranted, and confidence intervals can be derived from the data without prior assumption about the type of frequency distribution. This can be done by calculating the range within which 95% of all possible outcomes lie. Another popular method for this purpose is bootstrapping, which resamples at random from the study's own data. This paper reviews methods to assess data for compliance with normality, and summarizes solutions for the analysis of non-normal data. We strongly believe that normality statistics, although the mainstay of statistical analysis for centuries, will rapidly be replaced with non-normal testing as the awareness of non-normal sampling distributions grows, and we hope that the paper will strengthen this awareness and affect the design and analysis of future clinical trials.     

沟通管理在临床试验中面临的问题及对策研究

临床试验是推动人类健康事业向前发展的重要手段。每一种新药最终均需要进行临床试验才能最终确定药物的有效性和安全性。本文结合作者临床试验的工作经验,检索大量文献,深入分析了目前临床试验沟通管理中所存在的诸多问题,并有针对性地提出了改善临床试验沟通管理的相关对策,以期对更好地进行临床试验有所帮助。     

Estimating Covariate-Adjusted Log Hazard Ratios in Randomized Clinical Trials Using Cox Proportional Hazards Models and Nonparametric Randomization Based Analysis of Covariance

In the context of randomized clinical trials with time-to-event outcomes, estimates of covariate-adjusted log hazard ratios for comparing two treatments are obtained via nonparametric analysis of covariance by forcing the difference in means for covariables to zero. The method avoids the assumption of proportional hazards for each of the covariates, and it provides an adjusted analysis for the same population average treatment effect that the unadjusted analysis addresses. It is primarily useful in regulatory clinical trials that require analyses to be specified a priori. To illustrate, the method is applied to a study of lung disease with multivariate time-to-event outcomes.     

Stratification and Partial Ascertainment of Biomarker Value in Biomarker-Driven Clinical Trials

This article examines the role of stratification of treatment assignment with regard to biomarker value in clinical trials that accept biomarker-positive and -negative patients but have a primary objective of evaluating treatment effect separately for the marker-positive subset. It also examines the issue of incomplete ascertainment of biomarker value and how this affects inference about treatment effect for the biomarker-positive subset of patients. I find that stratifying the randomization for the biomarker ensures that all patients will have tissue collected but is not necessary for the validity of inference for the biomarker-positive subset if there is complete ascertainment. If there is not complete ascertainment of biomarker values, it is important to establish that ascertainment is independent of treatment assignment. Having a large proportion of cases with biomarker ascertainment is not necessary for establishing internal validity of the treatment evaluation in biomarker-positive patients; independence of ascertainment and treatment is the important factor. Having a large proportion of cases with biomarker ascertainment makes it more likely that biomarker-positive patients with ascertainment are representative of the biomarker-positive patients in the clinical trial (with and without ascertainment), but since the patients in the clinical trial are a convenience sample of the population of patients potentially eligible for the trial, requiring a large proportion of cases with ascertainment does not facilitate generalizability of conclusions.     

中医药临床试验受试者招募过程中的策略制定

受试者招募在一项临床试验中属于研究实施阶段的前期工作,如果招募工作没有完成或者招募质量没有保证将影响整个临床试验的进度和质量。本文从受试者招募流程、招募方式和影响受试者招募因素等几方面介绍受试者招募过程中的策略和方法,以期对进行临床试验尤其是中医药临床试验的研究者提供借鉴。     

药物临床试验实施阶段存在问题的问卷调查

目的：了解和探讨我国药物临床试验实施阶段存在的主要问题及对策。方法：采取目的抽样方法，以药物临床试验基地为研究现场，以参与过药物临床试验的医务人员为研究对象，采用自填式问卷调查获取相关问题的答案，应用Epidata 3．0录入数据，用SAS8.0软件进行统计分析。结果：148名研究对象中142名参加过药物临床试验的实施，实施中存在的主要问题是向研究对象收取试验用药费用、存在服药的依从性问题、有病例失访或中途退出时增补新病例、试验结果数据较少重复测定、GCP培训力度不够、实施前相关培训效果较低等。结论：培养科学的研究态度、加强培训力度、严格遵守GCP规范、加强质量监督与管理是提高我国药物临床试验实施质量的重要手段与途径。     

Statistical Monitoring of Clinical Trials With Multiple Co-Primary Endpoints Using Multivariate B-value

This article develops methods of statistical monitoring of clinical trials with multiple co-primary endpoints, where success is defined as meeting both endpoints simultaneously. In practice, a group sequential design (GSD) method is used to stop trials early for promising efficacy, and conditional power (CP) is used for futility stopping rules. In this article, we show that stopping boundaries for the GSD with multiple co-primary endpoints should be the same as those for studies with single endpoints. Lan and Wittes proposed the B-value tool to calculate the CP of single endpoint trials and we extend this tool to calculate the CP for studies with multiple co-primary endpoints. We consider the cases of two-arm studies with co-primary normal and provide an example of implementation with simulated trial. A fixed-weight sample size reestimation approach based on CP is introduced.     

Exact and Approximate Power and Sample Size Calculations for Analysis of Covariance in Randomized Clinical Trials With or Without Stratification

ABSTRACT

Analysis of covariance (ANCOVA) is commonly used in the analysis of randomized clinical trials to adjust for baseline covariates and improve the precision of the treatment effect estimate. We derive the exact power formulas for testing a homogeneous treatment effect in superiority, noninferiority, and equivalence trials under both unstratified and stratified randomizations, and for testing the overall treatment effect and treatment × stratum interaction in the presence of heterogeneous treatment effects when the covariates excluding the intercept, treatment, and prestratification factors are normally distributed. These formulas also work very well for nonnormal covariates. The sample size methods based on the normal approximation or the asymptotic variance generally underestimate the required size. We adapt the recently developed noniterative and two-step sample size procedures to the above tests. Both methods take into account the nonnormality of the t statistic, and the lower order variance term commonly ignored in the sample size estimation. Numerical examples demonstrate the excellent performance of the proposed methods particularly in small samples. We revisit the topic on the prestratification versus post-stratification by comparing their relative efficiency and power. Supplementary materials for this article are available online.     

药物临床试验质量控制与质量保证体系探讨

摘 要 通过解析和阐述我国药物临床试验各参与方申办者、研究者、临床试验机构及药品监督管理部门在试验质量控制与质量保证中的应有职责和存在问题,针对存在问题提出相应对策,为加强和完善我国药物临床试验质量控制与质量保证体系提出建议与期望。     

抗肿瘤新药临床试验的特殊性

目的:揭示抗肿瘤新药临床试验的特殊性,探索抗肿瘤药临床试验的适宜方法。方法:将抗肿瘤药临床试验与非抗肿瘤药临床试验在研究对象、试验设计、给药方案、疗效和安全性的观察与评价方面进行深入比较。结果:抗肿瘤药临床试验的研究对象是标准治疗失败或复发的肿瘤患者。为达到延长生存期的目标,医护人员和患者可能接受相对非抗肿瘤药更大的安全性风险,使得抗肿瘤药的风险效益权衡不同于非抗肿瘤药,其临床试验表现出相应的特殊性。结论:抗肿瘤新药临床试验较之非抗肿瘤药临床试验面临更多困难,需要花更多的精力去研究,临床试验水平亟需进一步提高。     

药师在药物临床试验中的实践与机遇

目的:探讨药师在药物临床试验领域的发展前景,为拓展医院药学积累经验。方法:采用波特五力模型和PEST模型对现阶段药师的优势、劣势、机遇和威胁进行评价;构建SWOT矩阵,制定发展战略。结果:药师在药物临床试验领域的优势和劣势均十分明显,机遇与威胁并存。结论:药师应抓住临床试验市场的机遇,坚定行业发展目标,确立自身发展空间和不可替代的地位。     

我国新药临床试验参与主体的风险管理

摘 要从风险管理的角度出发,剖析现阶段我国新药临床试验各参与主体包括申办者、研究者、受试者、伦理委员会及医疗机构可能面临的各类风险,并对如何管控和最小化风险提出建议和思考,期望采用正确、有效的管控策略最大程度地优化试验各方资源和降低风险,以达到保护受试者安全和获得高质量试验数据的目的。     

临床试验中靶向抗肿瘤药物不良反应分析

目的：比较分析4种靶向抗肿瘤药物的不良反应。方法：收集使用4种靶向抗肿瘤药物患者的临床资料,统计分析各种不良反应的类型和发生率,记录结果。结果：阿西替尼较常见的不良反应为高血压和腹泻;埃克替尼主要是皮疹和腹泻;利妥昔单抗使用时应注意其相关输液反应和感染;西妥昔单抗主要是痤疮样皮疹。结论：不同靶向药物其不良反应特点各不相同,临床医生应重点关注不同靶向药物常见或主要不良反应及其特点,及时处理重度甚至致死性不良反应,提高治疗的安全性和依从性。     

Quality of Life as an Outcome Measure for Epilepsy Clinical Trials.

Assessment of health-related quality of life (HRQOL) has been developed to the point where wellvalidated instruments are being used in clinical trials. Data on the impact of new treatments can be used for formulary and regulatory decisions if the clinical trials are designed with appropriate instruments and sample sizes. However, more information is needed about the clinical significance of small differences in total or scale scores. Similarly, pharmacoeconomic studies should be prospective assessments that include evaluation of HRQOL as well as cost. In the future, these new aspects of outcome assessment are expected to be used as an adjunct to traditional seizure frequency and adverse effect reports in the selection of antiepileptic drugs.