Surrogate endpoints

代理端点
  • 文章类型: Journal Article
    自身免疫性肝炎(AIH)的治疗目标是诱导缓解以防止肝纤维化的发展,肝硬化,及其相关并发症。已经使用了治疗反应和缓解的各种定义。国际自身免疫性肝炎组织(IAIHG)最近定义了治疗反应的共识标准。我们旨在验证我们队列中的IAIHG反应标准,并建立与生存终点的相关性。
    我们进行了回顾性研究,比利时一个三级和七个二级保健中心的多中心队列研究。符合条件的患者在数据收集时年龄至少为18岁,并且通过简化的IAIHG评分≥6被诊断为AIH。根据IAIHG共识标准将完全生化反应(CBR)定义为在治疗的前6个月内转氨酶和血清IgG的正常化。主要终点是肝脏相关生存-定义为肝脏相关死亡或肝移植的自由。次要终点是总死亡率和无移植生存率。比较获得CBR的患者和反应不足的患者的预后。
    可以在200例AIH患者中确定生化反应状态:128例(64.0%)个体达到CBR。未达到CBR的患者在初始组织学上更频繁地出现肝硬化(22.2%vs.10.9%,p=0.036)。26例患者(13.0%)发生肝脏相关死亡率或肝移植作为主要结局。实现CBR的患者表现出上肝相关(风险比0.118;95%CI0.052-0.267;p<0.0001)和总体(风险比0.253;95%CI0.111-0.572;p=0.0003)生存率。
    我们外部验证了IAIHG关于CBR的共识标准,并确认了它们与多中心生存终点的相关性,真实世界的队列。AIH患者以CBR为中间终点,具有明显优越的肝脏相关和总生存率。
    皮质类固醇仍然是诱导自身免疫性肝炎(AIH)疾病活动缓解的治疗基石,大多数患者需要长期皮质类固醇治疗以达到持续缓解。多年来,对治疗反应的定义各不相同,并且需要持续使用中间终点以促进非皮质类固醇治疗自身免疫性肝炎的进展.国际自身免疫性肝炎组织(IAIHG)定义了AIH治疗终点的共识标准,需要进一步的外部验证。这里,我们证明了IAIHG共识标准的有用性,并证实了它们与主要终点的相关性,例如多中心的肝脏相关存活率和天然肝脏存活率,真实世界的设置。未来研究的设计可以依靠IAIHG共识标准作为中间终点。
    UNASSIGNED: The goal of treatment in autoimmune hepatitis (AIH) is induction of remission to prevent the development of liver fibrosis, cirrhosis, and its related complications. Various definitions of treatment response and remission have been used. The International Autoimmune Hepatitis Group (IAIHG) recently defined consensus criteria for treatment response. We aimed to validate the IAIHG response criteria in our cohort and establish correlations with survival endpoints.
    UNASSIGNED: We performed a retrospective, multicentric cohort study in one tertiary and seven secondary care centres in Belgium. Eligible patients were at least 18 years of age at data collection and were diagnosed with AIH by a simplified IAIHG score of ≥6. Complete biochemical response (CBR) was defined according to the IAIHG consensus criteria as normalisation of transaminases and serum IgG within the first 6 months of treatment. The primary endpoint was liver-related survival - defined as freedom from liver-related death or liver transplantation. Secondary endpoints were overall mortality and transplant-free survival. Outcomes were compared between patients attaining CBR and those with insufficient response.
    UNASSIGNED: Biochemical response status could be determined in 200 patients with AIH: CBR was achieved in 128 (64.0%) individuals. Patients not achieving CBR more frequently presented with cirrhosis on initial histology (22.2% vs. 10.9%, p = 0.036). Liver-related mortality or liver transplantation as a primary outcome occurred in 26 patients (13.0%). Patients achieving CBR exhibited superior liver-related (hazard ratio 0.118; 95% CI 0.052-0.267; p <0.0001) and overall (hazard ratio 0.253; 95% CI 0.111-0.572; p = 0.0003) survival.
    UNASSIGNED: We externally validated the IAIHG consensus criteria for CBR and confirmed their correlation with survival endpoints in a multicentric, real-world cohort. Patients with AIH achieving CBR as an intermediate endpoint have significantly superior liver-related and overall survival.
    UNASSIGNED: Corticosteroids remain the cornerstone of treatment to induce remission of disease activity in autoimmune hepatitis (AIH), and the majority of patients require long-term corticosteroid treatment to achieve sustained remission. Definitions of response to treatment have varied over the years, and consistently used intermediate endpoints are needed to facilitate advancements in non-corticosteroid treatment for autoimmune hepatitis. The International Autoimmune Hepatitis Group (IAIHG) defined consensus criteria on endpoints in the treatment of AIH, for which further external validation is needed. Here, we demonstrate the usefulness of the IAIHG consensus criteria and corroborate their correlation to primary endpoints, such as liver-related survival and native liver survival in a multicentric, real-world setting. The design of future studies can rely on the IAIHG consensus criteria as intermediate endpoints.
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  • 文章类型: Journal Article
    目的:使用替代终点的主要目的是比使用真实终点更快地估计对真实终点的治疗效果。基于具有替代终点和真实终点的历史随机试验的荟萃回归,我们讨论了应用和评估替代端点的统计数据。
    方法:我们从两种类型的线性荟萃回归中计算了试验水平数据的统计数据:简单随机效应和新的随机效应,以及超过2组试验中估计的治疗效果之间的相关性。一个关键统计量是元回归线的估计截距。由于与单一因果途径的一致性和对作为对照的治疗标记的不变性,小或无统计学意义的截距增加了外推到新治疗时的置信度。对于将元回归应用于新治疗的监管者,一个有用的统计量是95%的预测区间。对于计划进行新疗法试验的临床试验人员来说,有用的统计数据是替代阈值效应比例,为丢失而调整的样本大小乘数,和新的真正的终点优势。
    结果:我们通过涉及抗高血压治疗的替代终点meta回归来说明这些统计数据,乳腺癌筛查,和结肠直肠癌治疗。
    结论:在应用和评估替代终点时,监管机构和试验人员应考虑使用这些统计数据。
    OBJECTIVE: The main purpose of using a surrogate endpoint is to estimate the treatment effect on the true endpoint sooner than with a true endpoint. Based on a meta-regression of historical randomized trials with surrogate and true endpoints, we discuss statistics for applying and evaluating surrogate endpoints.
    METHODS: We computed statistics from two types of linear meta-regressions for trial-level data: simple random effects and novel random effects with correlations among estimated treatment effects in trials with more than 2 arms. A key statistic is the estimated intercept of the meta-regression line. An intercept that is small or not statistically significant increases confidence when extrapolating to a new treatment because of consistency with a single causal pathway and invariance to labeling of treatments as controls. For a regulator applying the meta-regression to a new treatment, a useful statistic is the 95% prediction interval. For a clinical trialist planning a trial of a new treatment, useful statistics are the surrogate threshold effect proportion, the sample size multiplier adjusted for dropouts, and the novel true endpoint advantage.
    RESULTS: We illustrate these statistics with surrogate endpoint meta-regressions involving anti-hypertension treatment, breast cancer screening, and colorectal cancer treatment.
    CONCLUSIONS: Regulators and trialists should consider using these statistics when applying and evaluating surrogate endpoints.
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  • 文章类型: Journal Article
    临床试验中的疾病进展通常由放射学测量来定义。然而,临床进展可能对患者更有意义,即使不符合进展的放射学标准,也可能发生,在临床实践中经常需要改变治疗方法。这项研究的目的是确定在转移性实体瘤的全身治疗的III期试验中,基于进展的试验终点中临床进展标准的利用。对III期试验的主要手稿和方案进行了审查,以确定临床事件是否,如顽固性疼痛,肿瘤出血,或者神经妥协,可能构成一个进展事件。单变量逻辑回归计算了试验水平协变量与临床进展之间关联的比值比(OR)和95%CI。共有216项试验纳入148,190名患者,出版日期为2006年至2020年。13%的试验(n=27)的进展标准包括临床状态的重大变化,最常见的是作为次要终点(n=22)。只有59%的试验(n=16)报告了构成复合替代终点的不同临床进展结果。与其他疾病部位相比,泌尿生殖系统试验更有可能包括临床进展定义(16/33[48%]与11/183[6%];或,14.72;95%CI,5.99至37.84;p<0.0001)。虽然主要的肿瘤相关临床事件很少被认为是疾病进展事件。对临床进展的更多关注可能会提高转移性实体瘤患者替代终点的意义和临床适用性.
    Disease progression in clinical trials is commonly defined by radiologic measures. However, clinical progression may be more meaningful to patients, may occur even when radiologic criteria for progression are not met, and often requires a change in therapy in clinical practice. The objective of this study was to determine the utilization of clinical progression criteria within progression-based trial endpoints among phase III trials testing systemic therapies for metastatic solid tumors. The primary manuscripts and protocols of phase III trials were reviewed for whether clinical events, such as refractory pain, tumor bleeding, or neurologic compromise, could constitute a progression event. Univariable logistic regression computed odds ratios (OR) and 95% CI for associations between trial-level covariates and clinical progression. A total of 216 trials enrolling 148,190 patients were included, with publication dates from 2006 through 2020. A major change in clinical status was included in the progression criteria of 13% of trials (n = 27), most commonly as a secondary endpoint (n = 22). Only 59% of trials (n = 16) reported distinct clinical progression outcomes that constituted the composite surrogate endpoint. Compared with other disease sites, genitourinary trials were more likely to include clinical progression definitions (16/33 [48%] vs. 11/183 [6%]; OR, 14.72; 95% CI, 5.99 to 37.84; p < .0001). While major tumor-related clinical events were seldom considered as disease progression events, increased attention to clinical progression may improve the meaningfulness and clinical applicability of surrogate endpoints for patients with metastatic solid tumors.
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  • 文章类型: Journal Article
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  • 文章类型: Journal Article
    目的:量化过去二十年来美国食品和药物管理局(FDA)批准的新型癌症药物的随机对照试验(RCT)的统计证据的强度。
    方法:我们使用了总生存期(OS)的数据,无进展生存期(PFS),以及2000年1月至2020年12月FDA首次批准的新型癌症药物的肿瘤反应(TR)。我们通过计算所有可用终点的贝叶斯因子(BFs)来评估统计证据的强度,我们使用贝叶斯固定效应荟萃分析对基于两个RCT批准的适应症进行汇总。在终点之间比较了统计证据的强度,批准途径,治疗线,和癌症的类型。
    结果:我们分析了82个RCT的现有数据,这些数据对应于单个RCT支持的68个适应症和两个RCT支持的7个适应症。OS的统计证据的中值强度不明确(BF=1.9;IQR0.5-14.5),PFS(BF=24,767.8;IQR109.0-7.3*106)和TR(BF=113.9;IQR3.0-547,100)都很强。总的来说,44个适应症(58.7%)在没有明确的OS改善统计证据的情况下获得批准,7个适应症(9.3%)在没有任何终点改善统计证据的情况下获得批准。与所有三个终点的非加速批准相比,加速批准的统计证据强度较低。对于治疗线和癌症类型没有观察到有意义的差异。
    结论:本分析仅限于统计学证据。我们没有考虑非统计因素(例如,偏见的风险,证据的质量)。
    结论:BF为癌症药物批准的统计学证据提供了新的见解。大多数新型癌症药物缺乏强有力的统计证据表明它们可以改善OS,还有一些完全缺乏疗效的统计证据。这些案件需要透明和明确的解释。当证据含糊不清时,额外的上市后试验可以减少不确定性.
    OBJECTIVE: To quantify the strength of statistical evidence of randomized controlled trials (RCTs) for novel cancer drugs approved by the Food and Drug Administration in the last 2 decades.
    METHODS: We used data on overall survival (OS), progression-free survival, and tumor response for novel cancer drugs approved for the first time by the Food and Drug Administration between January 2000 and December 2020. We assessed strength of statistical evidence by calculating Bayes factors (BFs) for all available endpoints, and we pooled evidence using Bayesian fixed-effect meta-analysis for indications approved based on 2 RCTs. Strength of statistical evidence was compared among endpoints, approval pathways, lines of treatment, and types of cancer.
    RESULTS: We analysed the available data from 82 RCTs corresponding to 68 indications supported by a single RCT and 7 indications supported by 2 RCTs. Median strength of statistical evidence was ambiguous for OS (BF = 1.9; interquartile range [IQR] 0.5-14.5), and strong for progression-free survival (BF = 24,767.8; IQR 109.0-7.3 × 106) and tumor response (BF = 113.9; IQR 3.0-547,100). Overall, 44 indications (58.7%) were approved without clear statistical evidence for OS improvements and 7 indications (9.3%) were approved without statistical evidence for improvements on any endpoint. Strength of statistical evidence was lower for accelerated approval compared to nonaccelerated approval across all 3 endpoints. No meaningful differences were observed for line of treatment and cancer type. This analysis is limited to statistical evidence. We did not consider nonstatistical factors (eg, risk of bias, quality of the evidence).
    CONCLUSIONS: BFs offer novel insights into the strength of statistical evidence underlying cancer drug approvals. Most novel cancer drugs lack strong statistical evidence that they improve OS, and a few lack statistical evidence for efficacy altogether. These cases require a transparent and clear explanation. When evidence is ambiguous, additional postmarketing trials could reduce uncertainty.
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  • 文章类型: Journal Article
    由于更早的检测和改进的治疗,癌症患者的总生存期已经延长。然而,这些改进在评估新疗法的影响方面带来了挑战,特别是那些在治疗途径早期使用的。由于总体生存率仍然是大多数决策者首选的主要终点,治疗创新可能需要很长时间才能引入临床实践。此外,很难将研究结果推断到异质人群,并解决希望评估日常质量和延长寿命的患者的担忧.越来越多的人对使用替代或临时终点来比测量总生存期更快地证明稳健的治疗效果感兴趣。希望他们能加快患者获得新药的速度,组合,和序列,并告知治疗决策。然而,虽然替代终点已被监管机构用于药物批准,这是在个案基础上发生的。尚未明确定义证据标准,以便在卫生技术评估中获得可接受性或塑造临床实践。本文考虑了在英国背景下在癌症中使用替代终点的相关性,并探讨收集和分析真实世界的英国数据和证据是否有助于验证。
    Duration of overall survival in patients with cancer has lengthened due to earlier detection and improved treatments. However, these improvements have created challenges in assessing the impact of newer treatments, particularly those used early in the treatment pathway. As overall survival remains most decision-makers\' preferred primary endpoint, therapeutic innovations may take a long time to be introduced into clinical practice. Moreover, it is difficult to extrapolate findings to heterogeneous populations and address the concerns of patients wishing to evaluate everyday quality and extension of life. There is growing interest in the use of surrogate or interim endpoints to demonstrate robust treatment effects sooner than is possible with measurement of overall survival. It is hoped that they could speed up patients\' access to new drugs, combinations, and sequences, and inform treatment decision-making. However, while surrogate endpoints have been used by regulators for drug approvals, this has occurred on a case-by-case basis. Evidence standards are yet to be clearly defined for acceptability in health technology appraisals or to shape clinical practice. This article considers the relevance of the use of surrogate endpoints in cancer in the UK context, and explores whether collection and analysis of real-world UK data and evidence might contribute to validation.
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  • 文章类型: Editorial
    传统的牙科或牙周研究通常忽略人体成分,而有利于临床结果和生物学原因。临床研究是由结果参数的统计意义而不是患者的满意度驱动的。在这种情况下,以患者为中心的牙周研究(PCCPR)是一种考虑患者对其功能状态的反馈的方法,经验,临床结果,以及他们治疗的可及性。有人认为,由于患者个人信念的混淆作用,患者自我报告的数据可能具有较低的可靠性,文化背景,以及社会和经济因素。然而,文献表明,"以患者为中心的结局"成分的加入大大提高了研究结果的有效性和适用性.不同研究结果的差异可能是由于使用了不同的和非标准化的评估工具。为了克服这个问题,这篇社论列举了文献中可用的各种可靠工具。总之,我们主张研究者的研究重点应该从单纯的牙周研究转移到PCPR,这样研究结果可以有效地应用于临床,治疗策略也可以从单纯的牙周治疗转变为以患者为中心的牙周治疗.
    Conventional dentistry or periodontal research often ignores the human component in favor of clinical outcomes and biological causes. Clinical research is driven by the statistical significance of outcome parameters rather than the satisfaction level of the patient. In this context, patient-centric periodontal research (PCPR) is an approach that considers the patient´s feedback concerning their functional status, experience, clinical outcomes, and accessibility to their treatments. It is argued that data self-reported by the patient might have low reliability owing to the confounding effect of their personal belief, cultural background, and social and economic factors. However, literature has shown that the incorporation of \"patient-centric outcome\" components considerably enhances the validity and applicability of research findings. Variations in the results of different studies might be due to the use of different and non-standardized assessment tools. To overcome this problem, this editorial enlists various reliable tools available in the literature. In conclusion, we advocate that the focus of researchers should shift from mere periodontal research to PCPR so that the results can be effectively applied in clinical settings and the therapeutic strategy can also change from mere periodontal therapy to patient-centric periodontal therapy.
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  • 文章类型: Journal Article
    总生存期(OS)是临床试验中最有意义的终点。然而,由于其局限性,替代终点是常用的,需要进行验证研究以评估其可靠性.分析>100例晚期胃食管癌(AGC)的III期随机对照试验(RCT),相关系数(r),并通过荟萃分析评估OS和代孕之间的决定系数(R²)。无进展生存期(PFS),进展时间(TTP),和客观反应率(ORR)进行检查,以确定它们与OS的相关性。对65个III期RCT(29,766名受试者)的分析显示,PFS/TTP与OS之间存在中度相关性(r=0.77,R²=0.59),而ORR相关性较低(r=0.56,R²=0.31)。排除免疫治疗试验改善了PFS/TTP和OS的相关性(r=0.83,R²=0.70)。这些结果表明,PFS/TTP在AGC第三阶段调查中的潜在用途,忽略使用ORR作为代理端点。
    Overall survival (OS) is the most meaningful endpoint in clinical trials. However, owing to their limitations, surrogate endpoints are commonly used and validation studies are required to assess their reliability. Analysis of phase III randomized controlled trials (RCTs) of advanced gastroesophageal cancer (AGC) with > 100 patients, correlation coefficients (r), and determination coefficients (R²) between OS and surrogates were evaluated through meta-analyses. Progression-free survival (PFS), time to progression (TTP), and objective response rate (ORR) were examined to determine their correlations with OS. Analysis of 65 phase III RCTs (29,766 subjects) showed a moderate correlation between PFS/TTP and OS (r = 0.77, R² = 0.59), while ORR correlation was low (r = 0.56, R² = 0.31). Excluding immunotherapy trials improved the PFS/TTP and OS correlations (r = 0.83, R² = 0.70). These findings suggest the potential use of PFS/TTP in AGC phase III investigations, disregarding the use of ORR as a surrogate endpoint.
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  • 文章类型: Journal Article
    传统上,慢性淋巴细胞白血病(CLL)治疗的成功主要基于临床结果进行评估,如疾病反应,无进展生存期(PFS),总生存率(OS)。然而,治疗方法的演变认识到以患者为中心的观点的重要性,包括直接影响患者生活质量和总体幸福感的因素.
    使用PubMed和MEDLINE平台选择了针对目标药物对改善操作系统或其他终点代理的影响的研究。我们的搜索还包括考虑以患者为中心的终点的研究,例如与健康相关的生活质量和患者报告的结果(PRO)。
    CLL治疗的不断变化的格局强调了不断探索各种终点以彻底定义治疗成功的重要性。除了操作系统和代理端点等传统指标之外,即,PFS,下一次治疗时间(TTNT),和可测量的残留疾病(MRD)评估,将增强的合并症评估和以患者为中心的观点整合到CLL成功路线图中变得至关重要.随后的调查应该集中在增强当前的替代终点,辨别它们的上下文意义,并探索治疗效果和安全性的创新指标。鉴于CLL的动态性质和患者群体之间的异质性,个性化策略至关重要,考虑到个体特征和患者偏好。
    UNASSIGNED: Traditionally, the success of chronic lymphocytic leukemia (CLL) treatment has been primarily assessed based on clinical outcomes, such as disease response, progression-free survival (PFS), and overall survival (OS). However, the evolution of treatment approaches recognizes the importance of a patient-centered perspective that includes factors directly affecting patients\' quality of life and overall well-being.
    UNASSIGNED: Studies addressing the impact of targeted agents on improving either OS or other endpoint surrogates were selected using PubMed and MEDLINE platforms. Our search also included studies that considered patient-centric endpoints such as health-related quality of life and patient-reported outcomes (PROs).
    UNASSIGNED: The changing landscape of CLL treatment underscores the importance of continually exploring various endpoints to thoroughly define treatment success. Beyond conventional metrics such as OS and surrogate endpoints, namely, PFS, time to next treatment (TTNT), and measurable residual disease (MRD) assessment, it becomes crucial to integrate enhanced comorbidity evaluations and patient-centered viewpoints into a CLL success roadmap.Subsequent investigations ought to concentrate on enhancing current surrogate endpoints, discerning their contextual significance, and exploring innovative indicators of treatment efficacy and safety. Given the dynamic nature of CLL and the heterogeneity among patient groups, personalized strategies are essential, taking into account individual traits and patient preferences.
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  • 文章类型: Journal Article
    脑淀粉样血管病(CAA)是一种脑血管疾病,其特征是淀粉样蛋白在软脑膜和小型/中型脑血管中积聚。通常,脑出血是CAA的首要临床表现之一,对CAA的及时诊断构成了相当大的挑战,因为出血仅发生在疾病的后期。流体生物标志物可能在成像生物标志物之前发生变化,因此,他们可能是未来的CAA诊断。此外,它们可作为前瞻性临床试验的主要结局指标.在流体生物标志物中,与脑脊液生物标志物相比,基于血液的生物标志物具有明显的优势,因为它们不需要像腰椎穿刺那样的侵入性手术.本文旨在对目前与CAA相关的液体生物标志物的临床数据进行综述,并指出未来研究的方向。在所有讨论的生物标志物中,β淀粉样蛋白,神经丝轻链,基质金属蛋白酶,补体3,尿酸,和Lactadherin证明了最有希望的证据。然而,CAA的流体生物标志物领域是一个研究不足的领域,在大多数情况下,本综述中提到的每种生物标志物只有1至2项研究。此外,小样本量是所讨论研究的一个共同的局限性。因此,很难就每种生物标志物在疾病的不同阶段或CAA的各种亚群中的临床意义得出可靠的结论。为了克服这个问题,需要更大的纵向和多中心研究。
    Cerebral amyloid angiopathy (CAA) is a type of cerebrovascular disorder characterised by the accumulation of amyloid within the leptomeninges and small/medium-sized cerebral blood vessels. Typically, cerebral haemorrhages are one of the first clinical manifestations of CAA, posing a considerable challenge to the timely diagnosis of CAA as the bleedings only occur during the later disease stages. Fluid biomarkers may change prior to imaging biomarkers, and therefore, they could be the future of CAA diagnosis. Additionally, they can be used as primary outcome markers in prospective clinical trials. Among fluid biomarkers, blood-based biomarkers offer a distinct advantage over cerebrospinal fluid biomarkers as they do not require a procedure as invasive as a lumbar puncture. This article aimed to provide an overview of the present clinical data concerning fluid biomarkers associated with CAA and point out the direction of future studies. Among all the biomarkers discussed, amyloid β, neurofilament light chain, matrix metalloproteinases, complement 3, uric acid, and lactadherin demonstrated the most promising evidence. However, the field of fluid biomarkers for CAA is an under-researched area, and in most cases, there are only one or two studies on each of the biomarkers mentioned in this review. Additionally, a small sample size is a common limitation of the discussed studies. Hence, it is hard to reach a solid conclusion on the clinical significance of each biomarker at different stages of the disease or in various subpopulations of CAA. In order to overcome this issue, larger longitudinal and multicentered studies are needed.
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