In this study, we conducted an internet survey to understand the public's “recognition rate” and “understanding rate” of medical research terms. We chose to consider basic 12 medical research terms. In the recognition rate survey, for each of the 12 research terms, respondents were asked to select one of the following responses: “I understand its meaning”, “I have heard of it“, and “I have never heard of it”. We defined “recognized” with the answers “I understand the meaning” and “I have heard”. Further, the understanding rate survey was conducted such that the respondents selected one of five options that they thought were the correct explanations of the terms.

We obtained 1002 valid responses (response rate, 12.8%), and the results for each term were as follows (the figures in parentheses indicate the recognition rate and the understanding rate) : clinical studies (88.9％, 18.0％), chiken (85.4％, 14.5％), epidemiological studies (54.6％, 4.3％), intervention studies (10.9％, 2.5％), prospective clinical studies (12.8％, 2.0％), cohort studies (4.2％, 0.7％), phase Ⅰ clinical trials (10.0％, 2.6％), informed consent (55.2％, 9.9％), ethics review committees (66.8％, 23.7％), double-blind clinical trials (6.8％, 2.4％), placebo (20.8％, 14.2％), and randomized clinical trials (22.3％, 6.4％).

The results revealed that most of these medical research terms had a low recognition rate and also that the understanding rate was very low, in general. Consequently, researchers should understand that the public is unfamiliar with these medical research terms and, hence, should carefully explain to the research subjects the terms relevant to their research in the informed consent process.

The importance of incorporating patient insight in drug development is increasingly becoming recognized, empowered by the heightened awareness of patient-centric medical care. The purpose of this research is to identify specific processes in clinical trials that are not patient-centric, and to discuss how pharmaceutical companies and medical staff could cooperate, in order to develop patient-centric strategies in drug development.

In this research, we interviewed investigators, study coordinators and other medical staff involved in our clinical trials from April 2018 to October 2018.

Almost half of the medical staff answered that pharmaceutical companies should work on the development of Patient-Friendly Protocols (38.8％). The development of Patient-Friendly Informed Consent Documents (24.5％), the disclosure of clinical trial information (28.8％) and the disclosure of clinical trial results (34.6％) were also emphasized by medical staff as areas of improvement.

Interview results suggested that pharmaceutical companies should not only include patients, but also clinical trial staff in the process of incorporating patient preferences in order to overcome the lack of experience and knowledge of patients. Raising further awareness of the benefits of disclosing clinical trial information to patients is a challenge Japanese pharmaceutical companies, investigative sites and regulatory authorities should work on together.

The commitment of pharmaceutical companies and the cooperation of investigative sites are necessary to push forward patient-centric drug development in Japan.

Drug transporters are playing indispensable roles in the tissue uptake and efflux of drugs for efficient removal of drugs from the blood circulation. Endogenous biomarkers have been emerged for transporter phenotyping in humans without administration of probe drug administration. For instance, creatinine clearance was successful biomarker to find drugs that inhibit renal organic cation transporters, such as OCT2, MATE1 and MATE2-K, at their therapeutic doses. This review illustrated our recent studies to find endogenous substrates appropriate for phenotyping of drug transporters (OATP1B1 and OATP1B3, and OCT2). Appropriateness of the endogenous substrates as biomarker was supported by pharmacogenetic studies (OATP1B1^＊15 and OCT2 SNPs), and also by drug-drug interactions studies using rifampicin (OATP1B inhibitor). Of particular, there were significant correlations in the ratio of area under the plasma concentration time curve among the endogenous substrates (direct bilirubins, coproporphyrin Ⅰ and glycochenodeoxycholate-3-sulfate), and also between the endogenous substrates and an OATP1B1 probe drug, atorvastatin, in terms of rifampicin dose-dependence. It was strongly supported that the endogenous substrates can serve as quantitative OATP1B1 biomarkers. The endogenous biomarkers will be useful to find drugs that act as perpetrator in the drug-drug interactions in drug development, and clinical settings, and also to provide a deep understanding the factors inducing changes in drug transporter.