7-O-Succinyl macrolactin A (SMA) exerts several pharmacological effects including anti-bacterial, anti-inflammation, and anti-cancer activities. Recently, SMA has been extensively evaluated as an anti-cancer drug. Thus, the objectives of the present study were to characterise the pharmacokinetics of SMA via both non-compartmental and compartmental analysis in mice, rats, and dogs, and to derive an appropriate first-in-man dose based on allometric scaling of the animal data. The time courses of plasma SMA concentrations after intravenous administration to rats and dogs were analysed retrospectively, as were data collected after intraperitoneal SMA injection in mice. Pharmacokinetic parameters were estimated via both noncompartmental and compartmental analysis, and were correlated with body weight and/or the potential maximum life-span. The clearance and distribution volume of SMA in humans were predicted, and a first-in-man dose proposed. A two-compartment model best described the time courses of SMA plasma concentrations after a saturation elimination process was applied to fit the dataset obtained from rats. Incorporation of the maximum potential life-span during allometric scaling was required to improve the estimation of human clearance. The SMA clearance and the distribution volume in the steady state, in a 70-kg adult male, were estimated to be 30.6 L/h and 19.5 L, respectively. To meet the area under the curve (AUC) required for anti-tumour activity, a dose of 100 mg (∼1.5 mg/kg) was finally proposed as the first dose for a 70-kg human. Although toxicological profiles derived from non-clinical studies must be considered before any final decision is made, our work will facilitate clinical studies on SMA.
Administration, Intravenous ; Adult ; Animals ; Body Weight ; Dataset ; Dogs* ; Humans ; Male ; Mice* ; Pharmacokinetics ; Plasma ; Rats* ; Retrospective Studies

7-O-Succinyl macrolactin A (SMA) exerts several pharmacological effects including anti-bacterial, anti-inflammation, and anti-cancer activities. Recently, SMA has been extensively evaluated as an anti-cancer drug. Thus, the objectives of the present study were to characterise the pharmacokinetics of SMA via both non-compartmental and compartmental analysis in mice, rats, and dogs, and to derive an appropriate first-in-man dose based on allometric scaling of the animal data. The time courses of plasma SMA concentrations after intravenous administration to rats and dogs were analysed retrospectively, as were data collected after intraperitoneal SMA injection in mice. Pharmacokinetic parameters were estimated via both noncompartmental and compartmental analysis, and were correlated with body weight and/or the potential maximum life-span. The clearance and distribution volume of SMA in humans were predicted, and a first-in-man dose proposed. A two-compartment model best described the time courses of SMA plasma concentrations after a saturation elimination process was applied to fit the dataset obtained from rats. Incorporation of the maximum potential life-span during allometric scaling was required to improve the estimation of human clearance. The SMA clearance and the distribution volume in the steady state, in a 70-kg adult male, were estimated to be 30.6 L/h and 19.5 L, respectively. To meet the area under the curve (AUC) required for anti-tumour activity, a dose of 100 mg (∼1.5 mg/kg) was finally proposed as the first dose for a 70-kg human. Although toxicological profiles derived from non-clinical studies must be considered before any final decision is made, our work will facilitate clinical studies on SMA.
Administration, Intravenous ; Adult ; Animals ; Body Weight ; Dataset ; Dogs* ; Humans ; Male ; Mice* ; Pharmacokinetics ; Plasma ; Rats* ; Retrospective Studies

The pyrimidine nucleoside uridine has recently been reported to have a protective effect on cultured human corneal epithelial cells, in an animal model of dry eye and in patients. In this study, we investigate the pharmacokinetic profile of uridine in rabbits, following topical ocular (8 mg/eye), oral (450 mg/kg) and intravenous (100 mg/kg) administration. Blood and urine samples were serially taken, and uridine was measured by high-performance liquid chromatography-tandem mass spectrometry. No symptoms were noted in the animals after uridine treatment. Uridine was not detected in either plasma or urine after topical ocular administration, indicating no systemic exposure to uridine with this treatment route. Following a single intravenous dose, the plasma concentration of uridine showed a bi-exponential decay, with a rapid decline over 10 min, followed by a slow decay with a terminal half-life of 0.36 +/- 0.05 h. Clearance and volume of distribution were 1.8 +/- 0.6 L/h/kg and 0.58 +/- 0.32 L/kg, respectively. The area under the plasma concentration-time curves (AUC) was 59.7 +/- 18.2microg.hr/ml, and urinary excretion up to 12 hr was ~7.7% of the dose. Plasma uridine reached a peak of 25.8 +/- 4.1 microg/ml at 2.3 +/- 0.8 hr after oral administration. The AUC was 79.0 +/- 13.9 microg.hr/ml, representing ~29.4% of absolute bioavailability. About 1% of the oral dose was excreted in the urine. These results should prove useful in the design of future clinical and nonclinical studies conducted with uridine.
Administration, Intravenous* ; Administration, Ophthalmic ; Administration, Oral ; Animals ; Area Under Curve ; Biological Availability ; Epithelial Cells ; Half-Life ; Humans ; Mass Spectrometry ; Models, Animal ; Pharmacokinetics* ; Plasma ; Rabbits* ; Uridine*

Effects of diallyl sulfide (DAS) on thioacetamide-induced hepatotoxicity and immunotoxicity were investigated. When male Sprague-Dawley rats were treated orally with 100, 200 and 400 mg/kg of DAS in corn oil for three consecutive days, the activity of cytochrome P450 (CYP) 2E1-selective p-nitrophenol hydroxylase was dose-dependently suppressed. In addition, the activities of CYP 2B-selective benzyloxyresorufin O-debenzylase and pentoxyresorufin O-depentylase were significantly induced by the treatment with DAS. Western immunoblotting analyses also indicated the suppression of CYP 2E1 protein and/or the induction of CYP 2B protein by DAS. To investigate a possible role of metabolic activation by CYP enzymes in thioacetamide-induced hepatotoxicity, rats were pre-treated with 400 mg/kg of DAS for 3 days, followed by a single intraperitoneal treatment with 100 and 200 mg/kg of thioacetamide in saline for 24 hr. The activities of serum alanine aminotransferase and aspartate aminotransferase significantly elevated by thioacetamide were protected in DAS-pretreated animals. Likewise, the suppressed antibody response to sheep erythrocytes by thioacetamide was protected by DAS pretreatment in female BALB/c mice. Taken together, our present results indicated that thioacetamide might be activated to its toxic metabolite(s) by CYP 2E1, not by CYP 2B, in rats and mice.
Alanine Transaminase ; Animals ; Antibody Formation ; Aspartate Aminotransferases ; Biotransformation ; Blotting, Western ; Corn Oil ; Cytochrome P-450 CYP2E1* ; Cytochrome P-450 Enzyme System ; Erythrocytes ; Female ; Humans ; Male ; Mice ; Rats ; Rats, Sprague-Dawley ; Sheep ; Thioacetamide

BACKGROUND: There is a lack of research on the status of clinical trial pharmacy and clinical trial pharmacist (CTP) in Korea. This study was aimed to investigate the current status of clinical trial pharmacy and clinical trial pharmacists. METHODS: The survey was performed using the 41-item questionnaire designed to investigate information on the following; (1) current status of clinical trial pharmacy designated by Korea Food and Drug Administration, (2) current status of working condition, management, and satisfaction index of CTP. Data collected was analyzed by t-test and chi2. RESULTS: Among the CTPs who responded, 92.7% belonged to department of pharmacy, and 7.3% to clinical trial center. 90.2% of the respondents were women. Forty-two point seven percents of the respondents had more than 3 years of experience in the clinical trial field. 36.6% answered that the current number of CTPs in the institution was '2'. Sixty-three point four percents answered that they subsumed an additional post. Regarding the question on "whether the equipment and working environment of your clinical trials pharmacy is adequate", 65.1% of the respondents answered as 'Inadequate'. Ninety-eight point eight percents answered that work-related education is needed. Ninety-three point nine percents answered that the quality of clinical trials is related to the improvement of the working environment of CTP. CONCLUSION: Clinical trial pharmacy's facility and number of actually working CTP were insufficient. Proper and continuous education and training for CTPs are needed to improve the quality of clinical trials conducted in Korea, with strong institution support and timely regulation change.
Cytidine Triphosphate ; Surveys and Questionnaires ; Female ; Humans ; Korea ; Pharmacists ; Pharmacy ; Silanes ; United States Food and Drug Administration

BACKGROUND: Cyclosporine is an immunosuppressive agent used to treat and prevent graft versus host reaction (GVHR)-a complication associated with stem cell transplantation. This study aimed to develop a population pharmacokinetic model of cyclosporine and investigate factors affecting cyclosporine clearance in pediatric hematopoietic stem cell transplant patients. METHODS: A total of 650 cyclosporine concentrations recorded in 65 patients who underwent hematopoietic stem cell transplantation were used. Data including age, sex, weight, height, body surface area (BSA), type of disease, chemotherapy before stem cell transplantation, type of donor, serum creatinine levels, total bilirubin concentration, hematocrit value, and type of concomitant antifungal agents and methylprednisolone used were retrospectively collected. Data related to cyclosporine dosage, administration time, and blood concentration were also collected. All data were analyzed using the non-linear mixed effect model; a two-compartment model with first-order elimination was used. RESULTS: The population pharmacokinetic model of cyclosporine using the NONMEM program was as follows: CL (L/h) = 5.9 × (BSA / 1.2)0.9, V2 (L) = 54.5, Q (L/h) = 3.5, V3 (L) = 1080.0, ka (h-1) = 0.000377. BSA was selected as a covariate of cyclosporine clearance, which increased with an increase in BSA. CONCLUSION: A population pharmacokinetic model for Korean pediatric hematopoietic stem cell transplant patients was developed, and the important factor affecting cyclosporine clearance was found to be BSA. The model might contribute to the development of the most appropriate dosing regimen for cyclosporine. Further studies on population pharmacokinetics should be carried out, prospectively targeting pediatric patients.

Pharmacokinetic interaction of chrysin, a flavone present in honey, propolis and herbs, with caffeine was investigated in male Sprague-Dawley rats. Because chrysin inhibited CYP1A-selective ethoxyresorufin O-deethylase and methoxyresorufin O-demethylase activities in enriched rat liver microsomes, the pharmacokinetics of caffeine, a CYP 1A substrate, was studied following an intragastric administration with 100 mg/kg chrysin. In addition to the oral bioavailability of chrysin, its phase 2 metabolites, chrysin sulfate and chrysin glucuronide, were determined in rat plasma. As results, the pharmacokinetic parameters for caffeine and its three metabolites (i.e., paraxanthine, theobromine and theophylline) were not changed following chrysin treatment in vivo, despite of its inhibitory effect on CYP 1A in vitro. The bioavailability of chrysin was found to be almost zero, because chrysin was rapidly metabolized to its sulfate and glucuronide conjugates in rats. Taken together, it was concluded that the little interaction of chrysin with caffeine might be resulted from the rapid metabolism of chrysin to its phase 2 metabolites which would not have inhibitory effects on CYP enzymes responsible for caffeine metabolism.
Animals ; Biological Availability ; Caffeine* ; Cytochrome P-450 CYP1A1 ; Drug Interactions ; Honey ; Humans ; In Vitro Techniques ; Male ; Metabolism ; Microsomes, Liver ; Pharmacokinetics ; Plasma ; Propolis ; Rats* ; Rats, Sprague-Dawley ; Theobromine

Background: Need for regulatory science is emerging with the development of pharmaceutical industry. It is essential to train regulatory science experts to meet the needs of technology and regulations to evaluate advanced products. Major regulatory science countries are conducting the regulatory science activities and fostering the experts. Methods: Published literature and the relevant website of European Union (EU) were reviewed and criteria were developed. In particular, we focused on in depth descriptions of the Innovative Medicines Initiative program, which was conducted twice. Results: EU is striving to provide funding and training experts for the development of the regulatory science by horizon 2020 and regulatory science to 2025. Innovative medicines initiative (IMI) is a public-private partnership aimed at the development of the pharmaceutical industry, including the regulatory science. IMI education and training projects have provided various education and training course including short-term curriculum and master and doctoral course. The difference between South Korea’s regulatory science expert training project in 2021 and the EU’s IMI education and training projects is participation of pharmaceutical companies. While the pharmaceutical companies participate in the IMI project to select project topics and form a community, South Korea’s project is focused on the Ministry of Food and Drug Safety and universities. Conclusion Through successful active networks with regulatory party, pharmaceutical companies, and universities, a great innovative advance of regulatory science in South Korea is expected.

Background: The need for regulatory science development to evaluate advanced regulatory products is gradually increasing without hindering the technological development. Creating a research environment and fostering experts through the establishment of regulatory agency-led policies are essential for the development of regulatory science. Method: This is a comparative study of the United States, Japan, Singapore, and Korea. The literature and websites of each regulatory agency were reviewed, and the focus was on advantages and comparing advantages based on definition, development trends, and expert training projects. Results: The United States is striving to develop regulatory science in response to changes in the new pharmaceutical industry through the regulatory science report, and to foster expert both inside and outside the Food and Drug Administration (FDA). Japan is promoting regulatory science centered on regulatory science centers, and is focusing on researching work-related regulatory science within the Pharmaceuticals and Medical Devices Agency (PMDA) and improving employees’ ability to make regulatory decisions. Singapore was aiming to improve Southeast Asia’s regulatory capabilities under the leadership of Centre of Regulatory Excellence (CoRE) within Duke-NUS University. In 2021, Korea is in its early stages, starting to run a university's degree program related to regulatory science this year. Conclusion Regulatory science should be developed with the aim of improving the regulatory ability of the Ministry of Food and Drug Safety with Korea’s independent concept of regulatory science.

Background: Need for regulatory science is emerging with the development of pharmaceutical industry. It is essential to train regulatory science experts to meet the needs of technology and regulations to evaluate advanced products. Major regulatory science countries are conducting the regulatory science activities and fostering the experts. Methods: Published literature and the relevant website of European Union (EU) were reviewed and criteria were developed. In particular, we focused on in depth descriptions of the Innovative Medicines Initiative program, which was conducted twice. Results: EU is striving to provide funding and training experts for the development of the regulatory science by horizon 2020 and regulatory science to 2025. Innovative medicines initiative (IMI) is a public-private partnership aimed at the development of the pharmaceutical industry, including the regulatory science. IMI education and training projects have provided various education and training course including short-term curriculum and master and doctoral course. The difference between South Korea’s regulatory science expert training project in 2021 and the EU’s IMI education and training projects is participation of pharmaceutical companies. While the pharmaceutical companies participate in the IMI project to select project topics and form a community, South Korea’s project is focused on the Ministry of Food and Drug Safety and universities. Conclusion Through successful active networks with regulatory party, pharmaceutical companies, and universities, a great innovative advance of regulatory science in South Korea is expected.