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Cao H, Yao C, Yuan Y. Bayesian approach for design and analysis of medical device trials in the era of modern clinical studies. MEDICAL REVIEW (2021) 2023; 3:408-424. [PMID: 38283256 PMCID: PMC10810749 DOI: 10.1515/mr-2023-0026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 07/22/2023] [Indexed: 01/30/2024]
Abstract
Medical device technology develops rapidly, and the life cycle of a medical device is much shorter than drugs. It is necessary to evaluate the safety and effectiveness of a medical device in a timely manner to keep up with technology flux. Bayesian methods provides an efficient approach to addressing this challenge. In this article, we review the characteristics of the Bayesian approach and some Bayesian designs that were commonly used in medical device regulatory setting, including Bayesian adaptive design, Bayesian diagnostic design, Bayesian multiregional design, and Bayesian label expansion study. We illustrate these designs with medical devices approved by the US Food and Drug Administration (FDA). We also review several innovative Bayesian information borrowing methods, and briefly discuss the challenges and future directions of the Bayesian application in medical device trials. Our objective is to promote the use of the Bayesian approach to accelerate the development of innovative medical devices and their accessibility to patients for effective disease diagnoses and treatments.
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Affiliation(s)
- Han Cao
- Department of Biostatistics, Peking University First Hospital, Beijing, China
- Medical Data Science Center, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Chen Yao
- Department of Biostatistics, Peking University First Hospital, Beijing, China
- Peking University Clinical Research Institute, Beijing, China
- Hainan Institute of Real World Data, Qionghai, Hainan Province, China
| | - Ying Yuan
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, USA
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2
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Park J, Kang SH. Hierarchical Generalized Linear Models for Multiregional Clinical Trials. Stat Biopharm Res 2022. [DOI: 10.1080/19466315.2020.1862702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Junhui Park
- Department of Statistics and Data Science, Yonsei University, Seoul, Republic of Korea
| | - Seung-Ho Kang
- Department of Statistics and Data Science, Yonsei University, Seoul, Republic of Korea
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3
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Bean NW, Ibrahim JG, Psioda MA. Bayesian multiregional clinical trials using model averaging. Biostatistics 2021; 24:262-276. [PMID: 34296263 PMCID: PMC10102881 DOI: 10.1093/biostatistics/kxab027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 05/26/2021] [Accepted: 06/21/2021] [Indexed: 11/14/2022] Open
Abstract
Multiregional clinical trials (MRCTs) provide the benefit of more rapidly introducing drugs to the global market; however, small regional sample sizes can lead to poor estimation quality of region-specific effects when using current statistical methods. With the publication of the International Conference for Harmonisation E17 guideline in 2017, the MRCT design is recognized as a viable strategy that can be accepted by regional regulatory authorities, necessitating new statistical methods that improve the quality of region-specific inference. In this article, we develop a novel methodology for estimating region-specific and global treatment effects for MRCTs using Bayesian model averaging. This approach can be used for trials that compare two treatment groups with respect to a continuous outcome, and it allows for the incorporation of patient characteristics through the inclusion of covariates. We propose an approach that uses posterior model probabilities to quantify evidence in favor of consistency of treatment effects across all regions, and this metric can be used by regulatory authorities for drug approval. We show through simulations that the proposed modeling approach results in lower MSE than a fixed-effects linear regression model and better control of type I error rates than a Bayesian hierarchical model.
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Affiliation(s)
| | - Joseph G Ibrahim
- Department of Biostatistics, University of North Carolina, McGavran-Greenberg Hall, CB #7420, Chapel Hill, NC 27599, USA
| | - Matthew A Psioda
- Department of Biostatistics, University of North Carolina, McGavran-Greenberg Hall, CB #7420, Chapel Hill, NC 27599, USA
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4
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Wu SC, Xu JF, Zhang XJ, Li ZW, He J. Regional consistency and sample size considerations in a multiregional equivalence trial. Pharm Stat 2020; 19:897-908. [PMID: 32716135 DOI: 10.1002/pst.2044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 04/05/2020] [Accepted: 06/14/2020] [Indexed: 11/06/2022]
Abstract
The main objective of a confirmatory multiregional clinical trial (MRCT) is to demonstrate the overall efficacy of test drugs in all participating regions as well as to evaluate the possibility of extrapolating the overall results to each region. With the emergence of the demands of biosimilar drugs development, some guidelines recommended using equivalence design to demonstrate the comparability of efficacy between biosimilar and reference drugs. Previous discussions about assessing regional consistency in MRCT are mainly focused on superiority or non-inferiority designs, while the extensions to equivalence designs were limited. In this work, we proposed a flexible regional consistency criterion for the MRCT with equivalence design. Based on this criterion, sample size determination and sample allocation were also discussed.
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Affiliation(s)
- Si-Cheng Wu
- Biostatistics Office of Clinical Research Center, Shanghai 9th People's Hospital, Shanghai, China.,Department of Health Statistics, Second Military Medical University, Shanghai, China
| | - Jin-Fang Xu
- Department of Health Statistics, Second Military Medical University, Shanghai, China
| | - Xin-Ji Zhang
- Department of Health Statistics, Second Military Medical University, Shanghai, China
| | - Zhi-Wei Li
- School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, China
| | - Jia He
- Department of Health Statistics, Second Military Medical University, Shanghai, China
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5
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Affiliation(s)
- Saemina Kim
- Department of Applied Statistics, Yonsei University, Seoul, Korea
| | - Seung-Ho Kang
- Department of Applied Statistics, Yonsei University, Seoul, Korea
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6
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Gamalo-Siebers M, Tiwari R. Semi-parametric Bayesian regression for subgroup analysis in clinical trials. J Biopharm Stat 2019; 29:1024-1042. [PMID: 30747568 DOI: 10.1080/10543406.2019.1572613] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Determining whether there are differential treatment effects in subgroups of trial participants remains an important topic in clinical trials as precision medicine becomes ever more relevant. Any assessment of differential treatment effect is predicated on being able to estimate the treatment response accurately while satisfying constraints of balancing the risk of overlooking an important subgroup with the potential to make a decision based on a false discovery. While regression models, such as marginal interaction model, have been widely used to improve accuracy of subgroup parameter estimates by leveraging the relationship between treatment and covariate, there is still a possibility that it can lead to excessively conservative or anti-conservative results. Conceivably, this can be due to the use of the normal distribution as a default prior, which forces outlying subjects to have their means over-shrunk towards the population mean, and the data from such subjects may be excessively influential in estimation of both the overall mean response and the mean response for each subgroup, or a model mis-specification. To address this issue, we investigate the use of nonparametric Bayes, particularly Dirichlet process priors, to create semi-parametric models. These models represent uncertainty in the prior distribution for the overall response while accommodating heterogeneity among individual subgroups. They also account for the effect and variation due to the unaccounted terms. As a result, the models do not force estimates to excessively shrink but still retain the attractiveness of improved precision given by the narrower credible intervals. This is illustrated in extensive simulations investigating bias, mean squared error, coverage probability and credible interval widths. We applied the method on a simulated data based closely on the results of a cystic fibrosis Phase 2 trial.
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Affiliation(s)
| | - Ram Tiwari
- Division of Biostatistics, Center for Devices and Radiologic Health, Food and Drug Administration, Silver Spring, Maryland, USA
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7
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Serrano P, Hartmann M, Schmitt E, Franco P, Amexis G, Gross J, Mayer-Nicolai C. Clinical Development and Initial Approval of Novel Immune Checkpoint Inhibitors in Oncology: Insights From a Global Regulatory Perspective. Clin Pharmacol Ther 2018; 105:582-597. [PMID: 29923615 DOI: 10.1002/cpt.1123] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 05/18/2018] [Indexed: 12/28/2022]
Abstract
Immune checkpoint inhibitors (ICI) have demonstrated meaningful patterns of clinical efficacy across various cancers. During their development, novel regulatory strategies and clinical design approaches were explored. This metrics-based narrative review examines submission strategies and clinical evidence expectations of the US, European, and Japanese drug agencies, as well as their impact on approval and overall development times. Also discussed is the role of emerging clinical science and biomarker evaluation to get the first six ICI initially approved.
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Affiliation(s)
- Philippe Serrano
- R&D Regulatory Oncology, EMD Serono Research & Development Institute, Billerica, Massachusetts, USA
| | | | - Elmar Schmitt
- R&D Regulatory Oncology, Merck KGaA, Darmstadt, Germany
| | - Pedro Franco
- Global Regulatory & Scientific Policy, Merck Serono Europe Ltd, London, UK
| | | | - Jan Gross
- R&D Regulatory Oncology, Merck KGaA, Darmstadt, Germany
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8
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Statistical implications of extrapolating the overall result to the target region in multi-regional clinical trials. COMMUNICATIONS FOR STATISTICAL APPLICATIONS AND METHODS 2018. [DOI: 10.29220/csam.2018.25.4.341] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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9
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Teng Z, Lin J, Zhang B. Practical Recommendations for Regional Consistency Evaluation in Multi-Regional Clinical Trials with Different Endpoints. Stat Biopharm Res 2018. [DOI: 10.1080/19466315.2017.1379431] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Zhaoyang Teng
- Department of Biostatistics, Takeda Pharmaceuticals, Cambridge, MA
| | - Jianchang Lin
- Department of Biostatistics, Takeda Pharmaceuticals, Cambridge, MA
| | - Bin Zhang
- Department of Biostatistics, Seqirus Pharmaceuticals, Cambridge, MA
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Hsu YY, Zalkikar J, Tiwari RC. Hierarchical Bayes approach for subgroup analysis. Stat Methods Med Res 2017; 28:275-288. [DOI: 10.1177/0962280217721782] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
In clinical data analysis, both treatment effect estimation and consistency assessment are important for a better understanding of the drug efficacy for the benefit of subjects in individual subgroups. The linear mixed-effects model has been used for subgroup analysis to describe treatment differences among subgroups with great flexibility. The hierarchical Bayes approach has been applied to linear mixed-effects model to derive the posterior distributions of overall and subgroup treatment effects. In this article, we discuss the prior selection for variance components in hierarchical Bayes, estimation and decision making of the overall treatment effect, as well as consistency assessment of the treatment effects across the subgroups based on the posterior predictive p-value. Decision procedures are suggested using either the posterior probability or the Bayes factor. These decision procedures and their properties are illustrated using a simulated example with normally distributed response and repeated measurements.
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Affiliation(s)
- Yu-Yi Hsu
- U.S. Food and Drug Administration, Silver Spring, USA
| | | | - Ram C Tiwari
- U.S. Food and Drug Administration, Silver Spring, USA
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11
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Wang W, Jiang Z, Qiu J, Xia J, Guo X. A nested group sequential framework for regional evaluation in global drug development program. J Biopharm Stat 2017; 27:945-962. [PMID: 28323515 DOI: 10.1080/10543406.2017.1293079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The primary objective of a multiregional clinical trial (MRCT) is to assess the efficacy of all participating regions and evaluate the probability of applying the overall results to a specific region. The consistency assessment of the target region with the overall results is the most common way of evaluating the efficacy in a specific region. Recently, Huang et al. (2012) proposed an additional trial in the target region to an MRCT to evaluate the efficacy in the target ethnic (TE) population under the framework of simultaneous global drug development program (SGDDP). However, the operating characteristics of this statistical framework were not well considered. Therefore, a nested group sequential program for regional efficacy evaluation is proposed in this paper. It is an extension of Huang's SGDDP framework and allows interim analysis after MRCT and in the course of local clinical trial (LCT) phase. It is able to well control the family-wise type I error in the program level and enhances the flexibility of the program. In LCT sample size estimation, we introduce virtual trial, which is transformed from the original program by using discounting factor, and an iteration method is employed to calculate the sample size and stopping boundaries of interim analyses. The proposed sample size estimation method is validated in the simulations and the effect of varied weight, effect size of TE population, and design setting is explored. Examples with normal end point, binary end point, and survival end point are shown to illustrate the application of the proposed nested group sequential program.
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Affiliation(s)
- William Wang
- a Biostatistics and Research Decision Science , Merck Research Laboratory, Merck & Co., Inc ., Beijing , China
| | - Zhiwei Jiang
- a Biostatistics and Research Decision Science , Merck Research Laboratory, Merck & Co., Inc ., Beijing , China.,b Department of Health Statistics , School of Preventive Medicine, Fourth Military Medical University , Xi'an , Shaanxi , China
| | - Jingjun Qiu
- a Biostatistics and Research Decision Science , Merck Research Laboratory, Merck & Co., Inc ., Beijing , China.,b Department of Health Statistics , School of Preventive Medicine, Fourth Military Medical University , Xi'an , Shaanxi , China
| | - Jielai Xia
- b Department of Health Statistics , School of Preventive Medicine, Fourth Military Medical University , Xi'an , Shaanxi , China
| | - Xiang Guo
- a Biostatistics and Research Decision Science , Merck Research Laboratory, Merck & Co., Inc ., Beijing , China
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12
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Teng Z, Chen YF, Chang M. Unified additional requirement in consideration of regional approval for multiregional clinical trials. J Biopharm Stat 2017; 27:903-917. [PMID: 28287339 DOI: 10.1080/10543406.2017.1289942] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
To speed up the process of bringing a new drug to the market, more and more clinical trials are being conducted simultaneously in multiple regions. After demonstrating the overall drug's efficacy across regions, the regulatory and drug sponsor may also want to assess the drug's effect in specific region(s). Most of the recent approaches imposed a uniform criterion to assess the consistency of treatment effects between the interested region(s) and the entire study population regardless of the number of regions in multiregional clinical trials (MRCT). As a result, the needed sample size to achieve the desired probability of satisfying the regional requirement could be huge and implausible for the trial sponsors to implement. In this paper, we propose a unified additional requirement for regional approval by differing the parameters in the additional requirement depending on the number of planned regions. In particular, the values of the parameters are determined by a reasonable sample size increase with the desired probability satisfying the additional requirement. Considering the practicality of the global trial or sample size increase, we recommend specific values of the parameters for a different number of planned regions. We also introduce the assurance probability curve to evaluate the performance of different regional requirements.
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Affiliation(s)
- Zhaoyang Teng
- a Takeda Pharmaceuticals, Cambridge, Massachusetts , USA
| | - Yeh-Fong Chen
- b Division of Biometrics III, Center for Drug Evaluation and Research, US Food and Drug Administration , Silver Spring , Maryland , USA
| | - Mark Chang
- c Department of Biostatistics, Boston University , Boston , Massachusetts , USA.,d Veristat, Southborough , Massachusetts , USA
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13
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Zhou Y, Cui L, Yang B, Zhang L, Shen F. Regional efficacy assessment in multiregional clinical development. J Biopharm Stat 2016; 27:673-682. [PMID: 27315528 DOI: 10.1080/10543406.2016.1198369] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
It is common in multiregional clinical development that data from a global trial and a local trial (in a target country) together will be used to support local filing in the target country. This approach is considered efficient drug development both globally and in the target country. However, it remains a challenge how to combine global trial data and local trial data toward local filing. To address this challenge, we propose an "interpretation-centric" evaluation criterion based on a weighted estimator that weights data from the target country and outside of the target country. This approach provides an unbiased estimate of a global treatment effect with appropriate representation of the target country patient population, where the "appropriate representation" is the desired proportion of the target country participants in a global trial and is measured by the weight parameter. This natural interpretation can facilitate drug development discussion with local regulatory agencies. Sample size of the local trial can be determined using the proposed weighted estimator. Approaches for weight determination are also discussed.
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Affiliation(s)
- Yijie Zhou
- a Data and Statistical Sciences, AbbVie Inc. , North Chicago , Illinois , USA
| | - Lu Cui
- a Data and Statistical Sciences, AbbVie Inc. , North Chicago , Illinois , USA
| | - Bo Yang
- a Data and Statistical Sciences, AbbVie Inc. , North Chicago , Illinois , USA
| | - Lanju Zhang
- a Data and Statistical Sciences, AbbVie Inc. , North Chicago , Illinois , USA
| | - Frank Shen
- a Data and Statistical Sciences, AbbVie Inc. , North Chicago , Illinois , USA
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Wadsworth I, Hampson LV, Jaki T. Extrapolation of efficacy and other data to support the development of new medicines for children: A systematic review of methods. Stat Methods Med Res 2016; 27:398-413. [PMID: 26994211 DOI: 10.1177/0962280216631359] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE When developing new medicines for children, the potential to extrapolate from adult data to reduce the experimental burden in children is well recognised. However, significant assumptions about the similarity of adults and children are needed for extrapolations to be biologically plausible. We reviewed the literature to identify statistical methods that could be used to optimise extrapolations in paediatric drug development programmes. METHODS Web of Science was used to identify papers proposing methods relevant for using data from a 'source population' to support inferences for a 'target population'. Four key areas of methods development were targeted: paediatric clinical trials, trials extrapolating efficacy across ethnic groups or geographic regions, the use of historical data in contemporary clinical trials and using short-term endpoints to support inferences about long-term outcomes. RESULTS Searches identified 626 papers of which 52 met our inclusion criteria. From these we identified 102 methods comprising 58 Bayesian and 44 frequentist approaches. Most Bayesian methods (n = 54) sought to use existing data in the source population to create an informative prior distribution for a future clinical trial. Of these, 46 allowed the source data to be down-weighted to account for potential differences between populations. Bayesian and frequentist versions of methods were found for assessing whether key parameters of source and target populations are commensurate (n = 34). Fourteen frequentist methods synthesised data from different populations using a joint model or a weighted test statistic. CONCLUSIONS Several methods were identified as potentially applicable to paediatric drug development. Methods which can accommodate a heterogeneous target population and which allow data from a source population to be down-weighted are preferred. Methods assessing the commensurability of parameters may be used to determine whether it is appropriate to pool data across age groups to estimate treatment effects.
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Affiliation(s)
- Ian Wadsworth
- Department of Mathematics and Statistics, Fylde College, Lancaster University, Lancaster, UK
| | - Lisa V Hampson
- Department of Mathematics and Statistics, Fylde College, Lancaster University, Lancaster, UK
| | - Thomas Jaki
- Department of Mathematics and Statistics, Fylde College, Lancaster University, Lancaster, UK
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Koch A, Framke T. Reliably basing conclusions on subgroups of randomized clinical trials. J Biopharm Stat 2014; 24:42-57. [PMID: 24392977 DOI: 10.1080/10543406.2013.856020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The classical paradigm of Phase III clinical research is to demonstrate efficacy of a drug in an unselected patient population representative for later clinical practice. The flip side of the coin is that homogeneity of the treatment effect in subpopulations of the patient population cannot be assumed to be trivially given. Close inspection of relevant subgroups is important, as soon as overall efficacy has been demonstrated. This may lead to restrictions regarding the patient population to be treated. Similarly, although subgroup findings may be misleading, it should be possible in rare instances to base valid conclusions on subgroups of trials where this has not been precisely prespecified. Subgroups in multiregional clinical trials are different and deserve special consideration.
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Affiliation(s)
- Armin Koch
- a Institut für Biometrie, Medizinische Hochschule Hannover , Hannover , Germany
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16
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Sung PL, Chang YH, Chao KC, Chuang CM. Global distribution pattern of histological subtypes of epithelial ovarian cancer: a database analysis and systematic review. Gynecol Oncol 2014; 133:147-54. [PMID: 24556058 DOI: 10.1016/j.ygyno.2014.02.016] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Revised: 02/06/2014] [Accepted: 02/11/2014] [Indexed: 10/25/2022]
Abstract
BACKGROUND Epithelial ovarian cancer is basically a heterogeneous disease with different chemosensitivity and distinct molecular alternations for each histological subtype. In order to assess whether the results of clinical trials can be extrapolated to a new country, it is critical to first examine whether the relative frequencies is homogenous across countries. METHODS Cancer registry database from a single institution in Taiwan combined with systematic review of the global literature on the relative frequencies of histological subtypes between 2003 and 2012 was provided. RESULTS Of 175 titles identified, 41 studies met inclusion/exclusion criteria. Globally, for each subtype, the median value of relative frequencies for serous subtype was 45.0%, with the Philippines (16.0%), Indonesia (22.7%), and Brazil (30.1%) as the three lowest countries and South Africa (68.0%), Greece (71.5%), and India (86.7%) as the three highest countries; for mucinous subtype, 11.4%, Italy (3.0%), Australia (3.4%), and Japan (5.4%) were the three lowest countries, while Indonesia (29.1%), Singapore (30.3%), and South Korea (38.6%) were the three highest countries; for endometrioid subtype, 12.6%, India (1.6%), Greece (5.7%), and Portugal (7.6%) were the three lowest countries, while Taiwan (24.8%), Egypt (25.0%), and Austria (25.5%) were the three highest countries; and for clear cell subtype, 5.3%, Pakistan (1.0%), Iran (2.0%), and Brazil (2.1%) were the three lowest countries while Thailand (16.0%), Taiwan (16.8%), and Spain (18.8%) were the three highest countries. CONCLUSIONS Relative frequencies of subtypes were not homogenous across countries. This diversity may reflect the geographical and ethnic variations. Globally, epithelial ovarian cancer is a heterogeneous disease with a heterogeneous distribution pattern.
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Affiliation(s)
- Pi-Lin Sung
- Section of Gynecologic Oncology, Department of Obstetrics and Gynecology, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Yen-Hou Chang
- Section of Gynecologic Oncology, Department of Obstetrics and Gynecology, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Kuan-Chong Chao
- Section of Gynecologic Oncology, Department of Obstetrics and Gynecology, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Chi-Mu Chuang
- Section of Gynecologic Oncology, Department of Obstetrics and Gynecology, Taipei Veterans General Hospital, Taipei, Taiwan; Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Institute of Public Health, School of Medicine, National Yang-Ming University, Taiwan.
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17
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Tsong Y. Statistical considerations on design and analysis of bridging and multiregional clinical trials. J Biopharm Stat 2013; 22:1078-80. [PMID: 22946952 DOI: 10.1080/10543406.2012.702652] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Yi Tsong
- Office of Biostatistics, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland 20993, USA.
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18
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Tsou HH, Tsong Y, Chang WJ, Dong X, Hsiao CF. Design and Analysis Issues of Multiregional Clinical Trials with Different Regional Primary Endpoints. J Biopharm Stat 2012; 22:1051-9. [DOI: 10.1080/10543406.2012.701586] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Hsiao-Hui Tsou
- Division of Biostatistics and Bioinformatics, Institute of Population Health Sciences, National Health Research Institutes, Zhunan, Miaoli County, Taiwan.
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