• Communications for Statistical Applications and Methods
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• 제22권5호
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• pp.401-413
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• 2015

In this article, we review the statistical methods and theory for dose finding in early phase clinical trials, where the primary objective is to identify an acceptable dose for further clinical investigation. The dose finding literature is initially motivated by applications in phase I clinical trials, in which dose finding is often formulated as a percentile estimation problem. We will present some important phase I methods and give an update on new theoretical developments since a recent review by Cheung (2010), with an aim to cover a broader class of dose finding problems and to illustrate how the general dose finding theory may be applied to evaluate and improve a method. Specifically, we will illustrate theoretical techniques with some numerical results in the context of a phase I/II study that uses trinary toxicity/efficacy outcomes as basis of dose finding.

• Communications for Statistical Applications and Methods
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• 제19권6호
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• pp.877-884
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• 2012

Phase I trials determine the maximum tolerated dose(MTD) and the recommended dose(RD) for subsequent Phase II trials. In this paper, a MTD estimation method applied to a biased coin design is proposed for Phase I Clinical Trials. The suggested MTD estimation method is compared to the SM3 method and the NM method (Lee and Kim, 2012) using a Monte Carlo simulation study.

• Communications for Statistical Applications and Methods
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• 제26권2호
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• pp.163-173
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• 2019

Simon's two-stage designs are frequently used in phase II single-arm trials for efficacy studies. A concern of safety studies is too many patients who experience an adverse event. We show that Simon's two-stage designs for efficacy studies can be similarly used to design a two-stage safety study by modifying some of the design parameters. Given the type I and II error rates and the proportion of adverse events experienced in the first stage cohort, we prescribe a procedure whether to terminate the trial or proceed with a stage 2 trial by recruiting additional patients. We study the relationship between a two-stage design with a safety endpoint and an efficacy endpoint as well as use simulation studies to ascertain their properties. We provide a real-life application and a free R package gen2stage to facilitate direct use of two-stage designs in a safety study.

• Journal of the Korean Data and Information Science Society
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• 제15권4호
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• pp.973-980
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• 2004

Phase I clinical trials are often pharmacologically oriented and usually attempt to find the best dose of drug to employ. However, other purposes like determination of sizes and types of side effects and toxicity and organ system involved are equally important. Estimation of treatment effects or side effects is usually ignored since it is usually based on too small sample, even though Phase II clinical trials would be designed based on the Phase I studies. Statistical methods for constructing the approximate confidence interval for population median in case of small sample are considered and an improved method is proposed. The proposed estimator is compared with current methods through simulation studies.

• 한국콘텐츠학회논문지
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• 제13권4호
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• pp.281-289
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• 2013

최근 국내 임상시험의 양적 증가와 더불어, 임상시험 자료를 효율적으로 관리할 수 있는 Electronic Data Capture(EDC) 시스템의 도입 요구가 증가하고 있다. 이에 따라 식품의약품안전청에서는 '임상시험 전자 자료 처리 및 관리를 위한 가이드라인'을 발표하였다. 이는 향후 국내 임상시험 전자 자료 관리에 관한 법률 제정을 위한 기초가 될 것으로 기대한다. 이 연구에서는 국내 임상시험 관련 기관인 병원과 임상시험 수탁기관(CRO), 그리고 제약회사에서의 EDC 시스템 이용 현황과 관계자들이 인식하는 가이드라인 및 전자 자료 표준의 중요성 및 적용 용이성과 이해도를 조사하였다. 국내 임상시험 관련 기관에서의 EDC 시스템 이용률은 77.6% 이었지만 EDC 시스템을 이용한 임상시험 건수는 5건 미만이 가장 많았다. EDC 시스템은 주로 약물동력학 시험을 하는 phase I과 임상효과와 안전성을 평가하는 phase II 임상시험에서 주로 이용되었고, 기관별로는 CRO의 이용률이 가장 높았다. 모든 집단에서 가이드라인의 중요성은 높게 인식하였으나, 적용 용이성 측면에서는 CRO에서 가장 높았다. 또한, 임상시험 전자 자료 표준의 중요성을 높게 인식하였고, 전자 자료 수집에 있어 표준의 필요성을 높게 인식하였다. 그러나 임상시험 전자 자료 국제표준인 Clinical Data Interchange Standard Consortium(CDISC)에 대한 이해도는 아직 낮은 수준이었다. 이 연구 결과는 국내 임상시험 전자화를 위한 기초자료로 활용될 수 있으며 임상시험 자료 표준에 관한 정책수립에도 활용될 수 있을 것이다.

• 대한한의학회지
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• 제39권4호
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• pp.30-39
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• 2018

Introduction: The aim of this study protocol is to share and disclose the methodology used to develop an evidence-based clinical practice guideline (CPG) of therapeutic interventions used in Korean medicine for patients with stroke. Methods: The CPG development process will consist of two phases. In phase I, a development committee will be established, and they will decide the key questions to be answered. A systematic review and meta-analysis will be performed to answer these key questions by searching relevant randomized controlled trials and systematic reviews. Draft recommendations will be developed according to the evidence level and recommendation grades primarily determined using the GRADE methodology. Panels comprised of external experts will be formed, and surveys and a face-to-face meeting will be conducted to reach a consensus on the recommendations. A preliminary guideline will be created after final review by the development committee. In phase II, we will conduct clinical trials and economic analysis to supplement the lack of evidence found in the phase I. Conclusion: The CPG is expected to help doctors practicing Korean medicine in clinics or hospitals with making decisions based on the most reliable evidence, ultimately leading to the provision of optimal care for patients with stroke.

• 대한암한의학회지
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• 제20권1호
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• pp.11-21
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• 2015

Objectives : The cancer incidence and cancer burden is increasing. In addition, the use of botanical agents in cancer care is increasing. This article aims to review a research strategy for botanical agents. Methods : The clinical studies of anticancer botanical agents and the papers about clinical research methodology of botanical agents were reviewed. Results : In phase I study, safety confirmation, optimal dose determination and drug interaction study are important. Most botanical agents have low toxicity and some have non-monotone dose response. Therefore, dose-response curve must be evaluated separately from the dose-toxicity curve to determine optimal dose. Although anticancer botanical agents can't shrink tumor size rapidly, they do extend survival. So, in phase II study, response should be evaluated by the survival. Conclusions : Clinical research of botanical agents in cancer is different from traditional methods and strategies. Considering the characteristics of botanical agents and experimental mechanism is necessary in conducting botanical based clinical trials.

• 한국자원식물학회지
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• 제6권1호
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• pp.13-23
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• 1993

To data, many types of compounds having antineoplastic activity have been isolated from higher plants, that is, alkalodids, terpenes, lignans, steroids and so on. Some of ther were isolated from Indonesian plants, Curcuma xanthorrhiza and Eurycoma longifolia. Bisaborane type compounds were compounds were isolated as antimeoplastic compounds againest Sarcoma 180A from C. xanthorrhiza, and quassinoids and euryrene type triterpenes from triterpenes from El longifolia. Casearines, a kind of diterpene, had been isolated as cytotxic components from Casearia sylvestris distributed in South America. RA series Cyclic hexapeptides isolated from Rubia akane and R. cordifolia also have strong antineoplastic activity against various types of tumors. Till now, 16 kinds of RA series compounds were isolated and named as RA-I~XVI. Moreover, monoglucoside of RA-V newly isolated from same plant. Many kinds of derivatives including natural RA compounds were tested for QSAR, and one of them, RA-VII was screened up as a most suitable substance as an antitumor agent. RA-VII(=RA 700) has strong cytotoxic activity against KB cells, P388 lymphocytic leukemia and MM2 mammary carcinoma cells. In some solution, three conformers of RA-VII were observed by NMR. It was discussed the relationship between conformation and activity. Total synthesis was already completed, but there is left room for improvement. Phase I clinical trials for RA-VII has been finished, then Phase II trials will be started before long.

• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.2789-2800
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• 2013

Background: The aim of this systematic review was to investigate whether stem cells could be effectively applied in targeted therapy of breast cancer. Material and Method: A systematic literature search was performed for original articles published from January 2007 until May 2012. Results: Nine studies met the inclusion criteria for phase I or II clinical trials, of which three used stem cells as vehicles, two trials used autologous hematopoetic stem cells and in four trials cancer stem cells were targeted. Mesenchymal stem cells (MSCs) were applied as cellular vehicles to transfer therapeutic agents. Cell therapy with MSC can successfully target resistant cancers. Cancer stem cells were selectively targeted via a proteasome-dependent suicide gene leading to tumor regression. $Wnt/{\beta}$-catenin signaling pathway has been also evidenced to be an attractive CSC-target. Conclusions: This systematic review focused on two different concepts of stem cells and breast cancer marking a turning point in the trials that applied stem cells as cellular vehicles for targeted delivery therapy as well as CSC-targeted therapies. Applying stem cells as targeted therapy could be an effective therapeutic approach for treatment of breast cancer in the clinic and in therapeutic marketing; however this needs to be confirmed with further clinical investigations.

• 대한이식학회지
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• 제31권4호
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• pp.157-169
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• 2017

Regulatory T cells (Treg) naturally rein in immune attacks, and they can inhibit rejection of transplanted organs and even reverse the progression of autoimmune diseases in mice. The initial safety trials of Treg against graft-versus-host disease (GVHD) provided evidence that the adoptive transfer of Treg is safe and capable of limiting disease progression. Supported by such evidence, numerous clinical trials have been actively investigating the efficacy of Treg targeting autoimmune diseases, type I diabetes, and organ transplant rejection, including kidney and liver. The limited quantity of Treg cells harvested from peripheral blood and subsequent in vitro culture have posed a great challenge to large-scale clinical application of Treg; nevertheless, the concept of CAR (chimeric antigen receptor)-Treg has emerged as a potential resolution to the problem. Recently, two CAR-T therapies, tisagenlecleucel and axicabtagene ciloleucel, were approved by the US FDA for the treatment of refractory or recurrent acute lymhoblastic leukemia. This approval could serve as a guideline for the production protocols for other genetically engineered T cells for clinical use as well. The phase I and II clinical trials of these agents has demonstrated that genetically engineered and antigen-targeting T cells are safe and efficacious in humans. In conclusion, both the promising results of Treg cell therapy from the clinical studies and the recent FDA approval of CAR-T therapies are paving the way for CAR-Treg therapy in clinical use.