Kyushu University Academic Staff Educational and Research Activities Database
Researcher information (To researchers) Need Help? How to update
Koji Todaka Last modified date:2023.05.16

Professor / Center for Clinical and Translational Research
Center for Clinical and Translational Research(CCTR)
Kyushu University Hospital

Other Organization
Administration Post

 Reseacher Profiling Tool Kyushu University Pure
Research Focus

regulatory science (drug, medical device), Heart failure, cardiac function (pressure-volume relationship), diastolic dysfunction .
Academic Degree
Doctor of Medical Science
Country of degree conferring institution (Overseas)
Field of Specialization
cardiology, cardiac ventricular mechanics, heart failure, clinical trial, regulatory science
Total Priod of education and research career in the foreign country
Outline Activities
Translational research in various areas including cardiology which is his subspeciality

implementation of ARO infrastructure as a vice director of CCTR to support TR, development of technology seeds arisen from Kyushu University
research and human resource development in the regulatory science field
Research Interests
  • Establishing a decentralized clinical trial infrastructure with a standardized electronic worksheet as its core, from both systems and an operational perspective.
    keyword : drug discovery research, regulatory science
  • Research on resource dimension reduction and visualization of ARO function supported by seeds development results
    keyword : drug discovery research, regulatory science, medical sociology, health-care economy
  • Survey research for classification of ARO functions and creation of evaluation index by means of positioning analysis and heuristic methods
    keyword : regulatory science, positioning analysis, multiple indicator analysis
  • efficacy and safety evaluation method development for innovative therapeutic medical devices of cardiology
    keyword : regulatory science, risk matrix, text mining
  • International comparison of potential factors affecting medical technology acceptance by general public through risk-benefit perception
    keyword : risk perception, device lag, drug lag, zero risk, regulatory science
  • The double-blind comparative study on the efficacy of statin administration before coronary angioplasty in Japanese
    keyword : statin, PCI, double blind
    2006.10~2010.08The primary objective of this research is, to clarify whether or not treatment with relatively high doses of statin within the Japanese approved dose range given prior to PCI would improve prognosis in Japanese patients who will undergo PCI regardless of baseline LDL-C levels by conducting a randomized double-blind controlled clinical trial in order to determine positioning of statin for the treatment in Japanese patients with coronary artery diseases. In this research, whether or not early initiation of the treatment with statin prior to PCI would decrease the incidences of complications caused by PCI will be primarily investigated. Also, the incidences of cardiovascular events and restenosis, etc. up to 6 months after the operation will be investigated as the secondary endpoint..
  • Impact of cardiac rehabilitation on ventricular diastolic function
    keyword : diastolic dysfunction, exercise training
  • Basic Research of cardiac function by pressure-volume relationship
    keyword : pressure-volume relationship, end-systolic elastance
Current and Past Project
  • The applicant group conducted a study on the resources and results of 109 ARO facilities nationwide through the ARO Function Evaluation Project and obtained the following conclusions.
    a) Resources and outcomes are positively correlated but vary widely
    b) ARO intermediate results are classified into four indicators according to purpose
    1. Early development of IP and regulatory strategies
    2. Quasi-Pivotal trial design construction and execution
    3. Conduct safe clinical research and provide advanced medical care
    4. Human resource development and sustainability
    c) From the viewpoint of the efficiency of practical application such as approval, the level of resources (intellectual property charge, etc.) other than the clinical trials related to b) 1 above will lead to higher results (patents, etc.)

    These are the results of cross-sectional surveys as of 2019, and it is necessary to procpectively verify whether short-term results such as trials will lead to outcomes such as approval and provision of new medical care over the medium to long term.
    For this reason, a revised questionnaire will be created to narrow down the items, and a continuous survey will be conducted. The following resource list is updated at the same time as the change over time is grasped.

    A. Supporter's perspective
    Although ARO's detailed resource list has been prepared as an A-Concierge (MEXT), input has been weak and has not been used due to resistance to registration of personal occupations. On the other hand, in this proposal, it is possible to create a necessary and sufficient and up-to-date quantitative list of resources on human and material accounts from the above survey.
    Because it is a self-report, the effectiveness is secured by the following method.
    The "base support seeds information" registered by the base in AMED and the trial results of the above questionnaire, etc., as real data, provide strong support for support capabilities and specialty fields. With the consent, extract and transfer only the necessary data to a third-party organization, and then reduce and categorize the dimensions. At the same time, the number of seeds supported by type (products such as pharmaceuticals, medical devices, and regenerative medicine) In other words, quantify the “degree of specialty”.
    If a quantitative resource list and the "degree of specialty" based on the results that support it are presented at the same time, it becomes clear at a glance which ARO should be requested from a researcher.

    B. Perspective of support requester
    Researchers' requests for support vary depending on the characteristics of seeds, but in most cases they can be categorized as in the following example.

    Formulation of R & D strategy
    Formulation of intellectual property strategy
    Protocol creation support
    Statistical analysis design
    Data management
    Clinical trial support

    For these, a questionnaire survey will be conducted for researchers who have seeds. After analysis, the result is reflected in the support resource list and the support content evaluation.
  • In order to put the research seed technologies of universities into practical use, various functions (as major classification) as shown in Figure 1 are generally required. Translational Research Centers and Clinical Research Core Hospitals, so-called Centers, have these facilities, but individual resource allocation, unique fields are not evenly distributed. The ARO function typing that reflects them has not yet been systematically investigated. Last year, Mitsubishi Research Institute published the result of the major classification function survey of the “advanced treatment function hospitals” in this project but did not analyze it.
    Therefore, in order to categorize the ARO functions that leads to the creation of the evaluation scale this fiscal year, we will extract the service of 15 Centers based on the results of last year and also extract the lower classification of service functions from the table of charges etc. We will prepare survey forms by extracting important basic / nonclinical items, clinical items, etc. Survey on resource allocation (FTE, labor cost, etc.), output indicator (acquired research funds, number of patent applications, number of papers, etc.) related to functions using a questionnaire will be conducted at “advanced treatment hospitals” considered to have ARO function.
    The obtained data is analyzed and evaluated by the following two methods.
    1. Heuristic rule analysis: Experts who are good at ARO management are recruited through the ARO Council, National University Hospital Clinical Research Promotion Council, etc., and opinions are consolidated at the evaluation meeting. With several discussions, convergence of opinion, we classify ARO function empirically. The characteristics of ARO and meaningful outputs relationships are analyzed empirically by overviewing the whole.
    2. Positioning analysis: Positioning analyses such as principal component analysis, correspondence analysis, clustering, etc. for resource items, output items, and other ARO characteristics (national / private / NC, Kanto /Kansai / other areas, and objective typing without human intervention. By analyzing which outputs and which ARO function features are closer to each other on the mapping, we synthesize evaluation indexes that lead to good results for AROs of Centers or other sites separately (Fig. 2).
    At the same time, we investigate the minimum information for mapping ARO’s overseas in the same coordinates, and analyze their position and contrast characteristics.
    After comparing and examining the methods 1 and 2, we propose the evaluation index which indicates strong correlation with functional classification and output in a meaningful way from the academic standpoint.
Academic Activities
1. 戸高 浩司, Junji Kishimoto, Masayuki Ikeda, Koji Ikeda, Haruko Yamamoto, Impact of Risk-Benefit Perception and Trust on Medical Technology Acceptance in Relation to Drug and Device Lag: A Tripartite Cross-Sectional Survey, Therapeutic Innovation & Regulatory Science, 10.1177/2168479017739267, 52, 5, 629-640, First Published November 29, 2017, 2018.09, [URL], Background: New drug and medical device introduction in Japan usually lags behind that in the West. Many reports indicate that in Japan, the associated risks are considered greater than the benefits recognized in other countries. This study aimed to compare the relationship between risk-benefit perception and acceptance of medical technologies in 3 leading markets. Methods: A tri- partite cross-sectional survey of the general public was used. In total, 3345 adults in the United Kingdom, the United States, and Japan participated, and sexes and age groups were equally represented. Questions about the perception of risk, benefit, and acceptance of medical and other scientific technologies, and trust of medical product providers or regulatory authorities were included. Results: Five-step Likert coding for risk/benefit/acceptance of 4 medical items (x-rays, antibiotics, vaccines, and cardiac pacemakers) and 6 general items (such as automobiles and airplanes) were collected. Relationships between benefit perception and acceptance were linear for 4 medical technologies. The relationship had a similar slope but was shifted downward in Japan compared with the UK and US (P < .01), suggesting a lower acceptance in Japan for all benefit perceptions. The trend was the same between risk perception and acceptance, except for slopes that were negative. Correspondence analysis showed a strong correlation among acceptance of medical technologies, benefits of medical technologies, trust in doctors, and trust in the Department of Health. The UK and US attributes were clustered with positive responses such as “useful,” “acceptable,” and “trustworthy,” whereas Japan was clustered with intermediate to negative responses such as “neither” and “untrustworthy.” Conclusions: Acceptance of medical technologies was low in Japan because of significant differences in trust for doctors and authorities compared with that in the UK and US. This is a possible basis for delays of 24 to 60 months for medical product approval in Japan..
2. 木村 公則, 戸高 浩司, Nakanishi Y, Safety, Tolerability, and Preliminary Efficacy of the Anti-Fibrotic Small Molecule PRI-724, a CBP/β-Catenin Inhibitor, in Patients with Hepatitis C Virus-related Cirrhosis: A Single-Center, Open-Label, Dose Escalation Phase 1 Trial., EBioMedicine, 10.1016/j.ebiom.2017.08.016, 23, 79-87, 2017.09, BACKGROUND:

There is currently no anti-fibrotic drug therapy available to treat hepatitis C virus (HCV) cirrhosis. The aim of this study was to assess the safety, tolerability, and anti-fibrotic effect of PRI-724, a small-molecule modulator of Wnt signaling, in patients with HCV cirrhosis.

In this single-center, open-label, phase 1 trial, we sequentially enrolled patients with HCV cirrhosis who were classified as Child-Pugh (CP) class A or B. PRI-724 was administered as a continuous intravenous infusion of 10, 40, or 160mg/m2/day for six cycles of 1week on and 1week off. The primary endpoints were frequency and severity of adverse events. The secondary endpoint was efficacy of PRI-724 in treating cirrhosis based on CP score and liver biopsy. This study is registered with (no. NCT02195440).

Between Sept 3, 2014 and May 2, 2016, 14 patients were enrolled: CP class A:B, 6:8; median age, 62 (range: 43 to 74) years; male:female, 10:4. Twelve of the 14 patients completed six cycles of treatment; one was withdrawn from the study due to possible study drug-related liver injury (grade 3) in the 160mg/m2/day dose cohort and one withdrew for personal reasons. Serious adverse events occurred in three patients [21% (3/14)], one of which was possibly related to PRI-724. The most common adverse events were nausea [29% (4/14)] and fatigue [21% (3/14)]. After PRI-724 administration, the CP scores worsened by 1 point in two patients in the 10mg/m2/day cohort, improved in three patients at 1, 1, and 2 points in the 40mg/m2/day cohort, and improved in one patient by 3 points in the 160mg/m2/day cohort. The histology activity index scores of the liver tissue improved in two patients and exacerbated in two patients in the 10mg/m2/day cohort, and improved in one patient in the 40mg/m2/day cohort.

This study showed that administration of 10 or 40mg/m2/day intravenous PRI-724 over 12weeks was well-tolerated by patients with HCV cirrhosis; however, liver injury as a possible related serious adverse event was observed in the 160mg/m2/day cohort.

3. 西川 拓也, 朔 啓太, 戸高 浩司, Hiroyuki Tsutsui, Sunagawa K, The challenge of magnetic vagal nerve stimulation for myocardial infarction -preliminary clinical trial., Conf Proc IEEE Eng Med Biol Soc., 10.1109/EMBC.2017.8037812, 2017, 4321-4324, 2017.07, Numerous studies have shown in animal models that vagal nerve stimulation (VNS) strikingly reduces infarct size of acute myocardial infarction (AMI) and prevents heart failure. However, the lack of techniques to noninvasively stimulate the vagal nerve hinders VNS from clinical applications. Transcranial magnetic stimulation is noninvasive and capable of stimulating central neurons in patients. In this study, we examined whether the magnetic stimulation could noninvasively activate the cervical vagal nerve in healthy human. Sixteen healthy males and 4 females were enrolled in this study. We used Magstim Rapid2 with a 70-mm double coil in the right neck. We randomly assigned the subjects to 5 Hz or 20 Hz stimulation. We defined the maximum intensity of stimulation (MAX) which is the intensity just below the threshold of adverse effects. We defined HALF as a half of MAX. Protocols comprised 2 sets of MAX and 2 sets of HALF. Each stimulation continued for 3 minutes. We monitored heart rate (HR) and assessed the bradycardic response as an index of successful VNS. Nineteen subjects completed all protocols. They had no problematic adverse events during and/or after magnetic VNS. The magnetic VNS induced transient bradycardic responses in some subjects, whereas failed to induce sustained bradycardia in pooled data in any settings. Arterial pressure did not change either. Successful magnetic stimulation requires technical improvements including narrowing the magnetic focus and optimization of stimulation site. These improvements may enable us to apply magnetic VNS in the management of AMI..
4. Takase S, Tetsuya Matoba, Nakashiro S, Yasushi Mukai, Inoue S, Keiji Oi, Taiki Higo, Katsuki S, Takemoto M, Suematsu N, Eshima K, Miyata K, Yamamoto M, Usui M, Sadamatsu K, Satoh S, Kadokami T, Hironaga K, 戸高 浩司, Ezetimibe in Combination with Statins Ameliorates Endothelial Dysfunction in Coronary Arteries after Stenting: The CuVIC Trial, a Multicenter Randomized Controlled Trial, Arterioscler Thromb Vasc Biol., 37, 2, 350-358, 2017.02.
5. Uchida T, Ikeno F, Ikeda K, Suzuki Y, 戸高 浩司, Yokoi H, Thompson G, Krucoff M, Saito S, Global Cardiovascular Device Innovation: Japan-USA Synergies., Circ J, 77, 1714-1718, 2013.07, Background: Global medical devices have become more popular, but investment money for medical device development is not easily available in the market. Worldwide health-care budget constraints mean that efficient medical device development has become essential. To achieve efficient development, globalization is a key to success. Spending large amounts of money in different regions for medical device development is no longer feasible. Methods and Results: In order to streamline processes of global medical device development, an academic, governmental, and industrial consortium, called the Harmonization by Doing program, has been set up. The program has been operating between Japan and the USA since 2003. The program has 4 working groups: (1) Global Cardiovascular Device Trials; (2) Study on Post-Market Registry; (3) Clinical Trials; and (4) Infrastructure and Methodology Regulatory Convergence and Communication. Each working group has as its goals the achievement of speedy and efficient medical device development in Japan and the USA. The program has held multiple international meetings to deal with obstacles against efficient medical device development. Conclusions: This kind of program is very important to deliver novel medical devices. Involvement of physicians in this type of activity is also very helpful to achieve these goals..
6. Shimizu J, Todaka K, Burkhoff D, Load dependence of ventricular performance explained by model of calcium-myofilament interactions, American Journal of Physiology, 2002 Mar;282(3):H1081-91, 2002.03.
7. Todaka K, Wang J, Yi GH, Gu A, Zhu SM, Zhang H, Burkhoff D, Effect of BAY y 5959 on myocardial function and metabolism in normal and failing hearts., American Journal of Physiology, 274(5 Pt 2):H1560-8, 1998.05.
8. Todaka K, Ogino K, Gu A, Burkhoff D, Effect of ventricular stretch on contractile strength, calcium transient, and cAMP in intact canine hearts, American Journal of Physiology, 274, 3, H990-H1000, 274(3 Pt 2):H990-1000, 1998.03.
9. Todaka K, Wang J, Yi GH, Knecht M, Stennett R, Packer M, Burkhoff D, Impact of exercise training on ventricular properties in a canine model of congestive heart failure., American Journal of Physiology, 272(3 Pt 2):H1382-90, 1997.03.
10. Dickstein ML, Todaka K, Burkhoff D, Left-to-right systolic and diastolic ventricular interactions are dependent on right ventricular volume., American Journal of Physiology, 272(6 Pt 2):H2869-74, 1997.06.
11. Todaka K, Leibowitz D, Homma S, Fisher PE, DeRosa C, Stennett R, Packer M, Burkhoff D, Characterizing ventricular mechanics and energetics following repeated coronary microembolization., American Journal of Physiology, 272(1 Pt 2):H186-94, 1997.01.
Membership in Academic Society
  • Japan Society of Clinical Trials and Research
  • Japanese Society for Medical and Biological Engineering
  • Japanese Society of Clinical Pharmacology and Therapeutics
  • Japanese Heart Failure Society
  • The Japanese Circulation Society
  • The Japanese Society of Internal Medicine
Other Educational Activities
  • 2020.05.
  • 2020.06.
  • 2020.11.
  • 2020.12.
  • 2020.05.
  • 2020.08.
  • 2020.11.
  • 2020.12.
  • 2021.03.
  • 2021.03.
  • 2020.12.
  • 2020.11.
  • 2020.11.
  • 2019.12.
  • 2019.11.
  • 2019.11.
  • 2019.07.
  • 2019.12.
  • 2019.11.
  • 2019.08.
  • 2019.05.
  • 2019.12.
  • 2019.11.
  • 2019.06.
  • 2018.05.
  • 2018.12.
  • 2018.11.
  • 2019.05.
  • 2018.12.
  • 2018.10.
  • 2018.09.
  • 2018.05.
  • 2018.02.
  • 2018.01.
  • 2017.12.
  • 2017.12.
  • 2017.11.
  • 2017.09.
  • 2017.07.
  • 2017.06.
  • 2017.05.
  • 2017.02.
  • 2017.01.
  • 2016.12.
  • 2016.11.
  • 2016.09.
  • 2016.08.
  • 2016.08.
  • 2016.06.
  • 2016.05.
  • 2016.03.
  • 2016.02.
  • 2016.01.
  • 2015.10.
  • 2015.07.
  • 2015.06.
  • 2014.12.
  • 2014.11.
  • 2014.10.
  • 2014.06.
  • 2014.04.
  • 2013.12.
  • 2013.11.
  • 2013.06.
  • 2013.11.
  • 2013.05.
  • 2012.12.