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Interleukin-7 (IL-7) is an essential cytokine for T-cell homeostatic proliferation and maintenance. Clinical studies have shown the potential benefits of IL-7 therapy in various diseases associated with lymphopenia. However, the kinetics of the T-cell response to a single administration of IL-7 in humans have not been fully elucidated. Here, we investigated the effects of Fc-fused long-acting recombinant human IL-7 (hIL-7-hyFc, efineptakin alfa) on lymphocytes in healthy adults after a single subcutaneous or intramuscular administration. Administration of hIL-7-hyFc increased the CD8+ and CD4+ T-cell numbers up to 2.5-fold, with corresponding upregulation of Ki-67 and Bcl-2 expression, peaking at day 3 or 7. Regulatory T cells (Tregs) did not expand. Among CD8+ and CD4+ T cells, all T-cell subsets (TN, TEM, TCM, TEMRA, and TSCM) increased for 56 days. The T-cell receptor repertoire diversity of naive CD8+ and CD4+ T cells was increased by hIL-7-hyFc, whereas the memory T-cell subsets did not differ between day 56 and day 0. Transcriptomic analysis revealed that hIL-7-hyFc induced robust T-cell expansion without changes in gene expression profiles associated with T-cell functions or genes related to T-cell exhaustion, senescence, and anergy. The effector functions of antigen-specific CD8+ T cells were preserved after hIL-7-hyFc administration. Our results suggest that hIL-7-hyFc administration induced a sustained increase in the numbers of CD8+ and CD4+ T cells, but not Tregs, without qualitative changes. These results support the potential of hIL-7-hyFc as a treatment for patients with compromised T-cell immunity or as a vaccine adjuvant.

Hyun Chul Kim,1,2 Sangmi Lee,1,2 Siyoung Sung,3 Eunjin Kim,3 In-Jin Jang,1 Jae-Yong Chung4 1Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Hospital, Seoul, Republic of Korea; 2Integrated Major in Innovative Medical Science, Seoul National University Graduate School, Seoul, Republic of Korea; 3Dong-A ST Research Institute, Yongin-si, Gyeonggi-do, Republic of Korea; 4Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Bundang Hospital, Seongnam-si, Gyeonggi-do, Republic of KoreaCorrespondence: Jae-Yong Chung, Seoul National University College of Medicine and Bundang Hospital, Seongnam-si, Gyeonggi-do, 13620, Republic of Korea, Tel +82-31-787-3955, Fax +82-31-787-4045, Email jychung@snubh.orgBackground: Dapagliflozin formate (DAP-FOR, DA-2811), an ester prodrug of dapagliflozin, was developed to improve the stability and pharmaceutical manufacturing process of dapagliflozin, a sodium-glucose cotransporter-2 inhibitor.Purpose: This study aimed to evaluate the pharmacokinetics (PKs) and safety of dapagliflozin for DAP-FOR compared to those for dapagliflozin propanediol monohydrate (DAP-PDH, Forxiga) in healthy subjects.Methods: This was an open-label, randomized, single-dose, two-period, two-sequence crossover study. The subjects received a single dose of DAP-FOR or DAP-PDH 10 mg in each period, with a 7-day washout. Serial blood samples for PK analysis were collected up to 48 hours after a single administration to determine plasma concentrations of DAP-FOR and dapagliflozin. PK parameters were calculated using a non-compartmental method and compared between the two drugs.Results: In total, 28 subjects completed the study. DAP-FOR plasma concentrations were not detected in all of the blood sampling time points except for one time point in one subject, and the corresponding DAP-FOR plasma concentration in the subject was close to the lower limit of quantification. The mean plasma concentration–time profiles of dapagliflozin were comparable between the two drugs. The geometric mean ratios and its 90% confidence intervals of the maximum plasma concentration and area under the plasma concentration–time curve of dapagliflozin for DAP-FOR to DAP-PDH were within the conventional bioequivalence range of 0.80– 1.25. Both drugs were well-tolerated, with a similar incidence of adverse drug reactions.Conclusion: The rapid conversion of DAP-FOR into dapagliflozin led to the extremely low exposure of DAP-FOR and comparable PK profiles of dapagliflozin between DAP-FOR and DAP-PDH. The safety profiles were also similar between the two drugs. These results suggest that DAP-FOR can be used as an alternative to DAP-PDH.Keywords: prodrugs, dapagliflozin, pharmacokinetics, clinical trial, phase I

CT-P47 is a candidate tocilizumab biosimilar. This study assessed the pharmacokinetic (PK) equivalence of CT-P47 and European Union-approved reference tocilizumab (EU-tocilizumab) in healthy Asian adults. This double-blind, multicenter, parallel-group trial randomized healthy adults (1:1) to receive a single (162 mg/0.9 mL) subcutaneous dose of CT-P47 or EU-tocilizumab. The primary endpoint (Part 2) was PK equivalence by area under the concentration – time curve (AUC) from time zero to last quantifiable concentration (AUC0–last), AUC from time zero to infinity (AUC0–inf), and maximum serum concentration (Cmax). PK equivalence was concluded if 90% confidence intervals (CIs) for the ratios of geometric least-squares means (gLSMs) were within the 80–125% equivalence margin. Additional PK endpoints, immunogenicity, and safety were evaluated. In Part 2, 289 participants were randomized (146 CT-P47; 143 EU-tocilizumab); 284 received study drug. AUC0–last, AUC0–inf, and Cmax were equivalent between CT-P47 and EU-tocilizumab: 90% CIs for the ratios of gLSMs were within the 80–125% equivalence margin. Secondary PK endpoints, immunogenicity, and safety were comparable between groups. CT-P47 demonstrated PK equivalence with EU-tocilizumab and was well tolerated, following a single dose in healthy adults. www.clinicaltrials.gov identifier is NCT05188378. Tocilizumab is a biologic medicine used to treat inflammatory diseases including rheumatoid arthritis. Biosimilars are drugs that are highly similar to an already approved, ‘reference’ biologic medicine. This means that they do not have any differences from the reference product in factors including structure, biologic function, efficacy, and safety, that might affect how well they work in patients. Biosimilars are often available at a lower cost than reference drugs, so their use can provide patients with better access to expensive treatments. There are no approved biosimilars of tocilizumab so far: CT-P47 is currently in development as a potential tocilizumab biosimilar. In the main part of this study, 289 healthy Asian volunteers were randomly allocated to receive a single injection of either CT-P47 or the reference drug, European Union-approved tocilizumab (EU-tocilizumab). The main aim of the study was to find out whether CT-P47 and EU-tocilizumab were equivalent in terms of pharmacokinetics (drug absorption, distribution, metabolism, and excretion by the body). This is part of a standard process required by regulatory authorities to ensure that biosimilars work as well as their reference drugs. Analysis of blood samples taken over 43 days showed that the pharmacokinetic profiles of CT-P47 and EU-tocilizumab were equivalent, after the volunteers received a single dose of either drug. Safety and immunogenicity (immune responses made to the drug) were also comparable between CT-P47 and EU-tocilizumab. While only healthy Asian adults were included, further research comparing CT-P47 with reference tocilizumab will help to ensure that the findings from the study can be applied to broader populations.

Interleukin-7 (IL-7) is an essential cytokine for T-cell homeostatic proliferation and maintenance. Clinical studies have shown the potential benefits of IL-7 therapy in various diseases associated with lymphopenia. However, the kinetics of the T-cell response to a single administration of IL-7 in humans have not been fully elucidated. Here, we investigated the effects of Fc-fused long-acting recombinant human IL-7 (hIL-7-hyFc, efineptakin alfa) on lymphocytes in healthy adults after a single subcutaneous or intramuscular administration. Administration of hIL-7-hyFc increased the CD8+ and CD4+ T-cell numbers up to 2.5-fold, with corresponding upregulation of Ki-67 and Bcl-2 expression, peaking at day 3 or 7. Regulatory T cells did not expand. Among CD8+ and CD4+ T cells, all T-cell subsets (TN, TEM, TCM, TEMRA, and TSCM) increased for 56 days. The TCR repertoire diversity of naïve CD8+ and CD4+ T cells was increased by hIL-7-hyFc, while the memory T-cell subsets did not differ between D56 and D0. Transcriptomic analysis revealed that hIL-7-hyFc induced robust T-cell expansion without changes in gene expression profiles associated with T-cell functions or genes related to T-cell exhaustion, senescence, and anergy. The effector functions of antigen-specific CD8+ T cells were preserved after hIL-7-hyFc administration. Our results suggest that hIL-7-hyFc administration induced a sustained increase in the numbers of CD8+ and CD4+ T cells, but not regulatory T cells, without qualitative changes. These results support the potential of hIL-7-hyFc as a treatment for patients with compromised T-cell immunity or as a vaccine adjuvant.

Omeprazole blocks the gastric H+ /K+ adenosine triphosphatase, thus inhibiting gastric acid secretion, and is metabolized by cytochrome P450 (CYP) 2C19. Due to the physiological changes in the elderly, there are different pharmacokinetic consequences compared to young people. The aim of this study was to evaluate the pharmacokinetic profiles of omeprazole in 15 elderly participants according to the CYP2C19 genotype. The concentration-time profiles of omeprazole and its metabolites, 5-hydroxy (5-OH) omeprazole and omeprazole sulfone, were similar between the CYP2C19 extensive metabolizer (EM) and intermediate metabolizer groups. In contrast, when comparing the EM group and CYP2C19 poor metabolizer (PM) group, the EM/PM geometric mean ratio (95% confidence interval) of area under the plasma concentration-time curve from time of dosing to the last measurable concentration was 0.52 (0.27-1.01) and that of the IM group was 0.71 (0.32-1.59), indicating that the exposure of omeprazole in the PM group was increased. The exposure of 5-OH omeprazole was significantly decreased in the PM group when compared to the EM group, with an EM/PM geometric mean ratio (95% confidence interval) of 2.20 (1.50-3.22). In conclusion, the tendency of drug exposure according to the CYP2C19 genotype in the elderly and young adults was similar in that the exposure level was highest in the PM group. However, when compared to young adults, the difference between the genotype groups was smaller in the elderly.

Purpose Herpes zoster (HZ), or shingles, is a clinical syndrome resulting from the reactivation of latent varicella zoster virus (VZV) within the sensory ganglia. We evaluated the safety and tolerability of ES16001 (ethanol extract of Elaeocarpus sylvestris var. ellipticus), a novel inhibitor of varicella zoster virus reactivation in healthy adults. Method Single-center, randomized, double-blind, placebo-controlled, single and multiple ascending dose (SAD and MAD, respectively) studies were conducted in 20- to 45-year-old healthy adults without chronic disease. In the SAD study (n = 32), subjects randomly received a single oral dose of 240, 480, 960, or 1440 mg ES16001 or a placebo. In the MAD study (n = 16), subjects randomly received once daily doses of 480 or 960 mg ES16001 or a placebo for 5 days. The safety and tolerability of the drug were evaluated by monitoring participants’ treatment emergent adverse events (TEAEs) and vital signs, electrocardiograms (ECGs), physical examinations, and clinical laboratory tests. Results In the SAD study, 11 adverse reactions were seen in 5 subjects, and in the MAD study, 8 adverse reactions were seen in 6 subjects. All adverse reactions were mild, and no serious adverse reactions occurred. The most common adverse reaction was an increase in alanine aminotransferase (ALT), but all test values were in the clinically non-significant range, and their clinical significance was judged to be small considering the fact that most of the test values returned to normal immediately after the end of drug administration. Conclusion ES16001 has good safety and tolerability when administered both once and repeatedly to healthy subjects. Further research is needed to identify any possible drug-induced hepatotoxicity, which appears infrequently. Our findings provide a rationale for further clinical investigations of ES16001 for the prevention of HZ. Trial registration: CRIS, KCT0006066. Registered 7 April 2021—Retrospectively registered, https://cris.nih.go.kr/cris/search/detailSearch.do/19071).

This study aimed to demonstrate pharmacokinetic (PK) equivalence of a single dose of the proposed adalimumab biosimilar CT‐P17 to United States‐licensed adalimumab (US‐adalimumab) and European Union‐approved adalimumab (EU‐adalimumab). This double‐blind, parallel‐group, phase I trial (clinicaltrials.gov NCT03970824) was conducted at 10 hospitals (Republic of Korea), in which healthy subjects (1:1:1) were randomized to receive a single 40 mg (100 mg/ml) subcutaneous injection of CT‐P17, US‐adalimumab, or EU‐adalimumab. Primary end points were PK equivalence in terms of: area under the concentration–time curve from time zero to infinity (AUC0–inf); AUC from time zero to the last quantifiable concentration (AUC0–last); and maximum serum concentration (Cmax). PK equivalence was concluded if 90% confidence intervals (CIs) for percent ratios of geometric least squares means (GLSMs) for pairwise comparisons were within the equivalence margin of 80–125%. Additional PK end points, safety, and immunogenicity were evaluated. Of the 312 subjects who were randomized (103 CT‐P17; 103 US‐adalimumab; 106 EU‐adalimumab), 308 subjects received study drug. AUC0–inf, AUC0–last, and Cmax were equivalent among CT‐P17, US‐adalimumab, and EU‐adalimumab, because 90% CIs for the ratios of GLSMs were within the 80–125% equivalence margin for each pairwise comparison. Secondary PK end points, safety, and immunogenicity were similar between treatment groups. In conclusion, PK equivalence for single‐dose administration of CT‐P17, EU‐adalimumab, and US‐adalimumab was demonstrated in healthy adults. Safety and immunogenicity profiles were comparable between treatment groups and consistent with previous reports for adalimumab biosimilars.

Hypertension is more effectively treated with coadministration of 2 or more antihypertensive drugs than with high-dose monotherapy. Therefore, calcium channel blockers, angiotensin II receptor blockers, and thiazides are coadministered to treat hypertension. The objective of this study was to compare the pharmacokinetic (PK) profiles of HCP1401, a fixed-dose combination of amlodipine 5 mg, losartan 100 mg, and chlorthalidone 25 mg, with the separate components (loose combination) of amlodipine/losartan 5/100 mg and chlorthalidone 25 mg. A randomized, open-label, single-dose, 2-way crossover study was conducted. Blood samples for amlodipine and chlorthalidone were collected for up to 144 hours after dosing, whereas those for losartan were collected up to 48 hours after dosing. The PK parameters of these drugs were calculated using a noncompartmental method. Sixty subjects completed the study. The geometric mean ratios and 90% confidence intervals of maximum plasma concentration and area under the concentration-time curve to the last measurable point for amlodipine, losartan, and chlorthalidone were within the conventional bioequivalence range of 0.80 to 1.25. There were no clinically significant changes in safety assessments, and the treatments were well tolerated. The PK characteristics and tolerability profiles of a single oral FDC of amlodipine, losartan, and chlorthalidone were equivalent to those of individual tablets in a loose combination.

Sejung Hwang,1 Dae Young Lee,2 Joo-Youn Cho,1,3 Jae-Yong Chung,4 In-Jin Jang,1 Kyung-Sang Yu,1,3 SeungHwan Lee1 1Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Hospital, Seoul, Republic of Korea; 2Drug Metabolism and Pharmacokinetics (DMPK), Drug Evaluation, Dong-A ST Research Institute, Gyonggi-do, Republic of Korea; 3Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea; 4Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Bundang Hospital, Seongnam, Republic of KoreaCorrespondence: SeungHwan LeeDepartment of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Hospital, 101 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of KoreaTel +82-2-2072-2343Fax +82-2-2072-0720Email leejh413@snu.ac.krPurpose: DA-8031 is a novel selective serotonin reuptake inhibitor for the treatment of premature ejaculation. This study investigated the pharmacokinetics, safety and tolerability of multiple oral doses of DA-8031. In addition, a genetic analysis was explored to evaluate the effect of genetic polymorphisms on the pharmacokinetics of DA-8031.Subjects and Methods: A dose block-randomized, double-blind, placebo-controlled study was conducted in 3 dose groups with 20, 30 and 40 mg of DA-8031. Healthy male subjects were randomized to DA-8031 or placebo at a 4:1 ratio in each dose group of 10 subjects by oral administration once daily for 7 consecutive days. Serial blood and urine samples were collected for the pharmacokinetic evaluation, and the pharmacokinetic-related genes were analyzed by DMETTM plus. A safety evaluation was conducted including adverse events (AEs) monitoring and 12-lead electrocardiogram (ECG).Results: The plasma DA-8031 concentration reached the maximum concentration (Cmax) in 2.2 to 3.0 h and was eliminated with a mean half-life of 25.5 to 26.7 h at steady state. The accumulation index of DA-8031 ranged 2.3 to 2.8. The systemic exposure of DA-8031 of the CYP2D6 intermediate metabolizer (IM) was significantly higher compared to the CYP2D6 poor metabolizer (PM). There were no clinically significant QTc interval changes, and all the adverse events were mild.Conclusion: After multiple oral doses of DA-8031 20, 30, and 40 mg in this study, the systemic exposure of DA-8031 increased in a more than dose-proportional manner with the increasing doses, and DA-8031 was generally well tolerated. In addition, the genetic polymorphisms of CYP2D6 have an impact on the pharmacokinetics of DA-8031.Keywords: selective serotonin reuptake inhibitors, clinical pharmacology, phase 1 study, pharmacogenomics

Background A thorough QT study identified that escitalopram-induced QT prolongation was delayed. This study thus aimed to develop a population pharmacokinetic (PK)/pharmacodynamic (PD) model to characterize the relationship between escitalopram concentrations and the delayed effect on QT prolongation. Methods The data of completed subjects who had placebo (n=36) and a single dose of 20 mg escitalopram (n=33) from a previous thorough QT study were used. Population PK/PD analysis was performed by nonlinear mixed-effects modeling. A escitalopram concentration-drug effect model was developed with estimated individual PK and baseline QT parameters. To explain the relationship between escitalopram concentrations and QT prolongation delay, an effect compartment model was utilized. Results A two-compartment model with first-order absorption and lag time and first-order elimination adequately described the PK of escitalopram. The circadian rhythm of baseline QT interval was best explained by two harmonic cosine functions. A linear model properly characterized escitalopram-induced QT prolongation. The average estimated maximal QT prolongation was 5.4 ms (range: 1.9-7.6 ms). The equilibrium half-life of delayed QT prolongation was 1.9 h. The drug effect of QTc change compared with that at baseline remained relatively constant from 1.3 to 3.5 ms over 24 h, and the maximum QTc change occurred with a 3-h delay after the time to the maximum plasma concentration. Limitations We did not include genetic polymorphisms, such as CYP2C19, as potential covariates owing to limited information. Conclusions These results may provide useful information on when to monitor electrocardiogram in patients who require intensive care after drug administration.

Aims Rifampicin is a key drug for the treatment of tuberculosis (TB). Little is known for the relationship between the rifampicin pharmacokinetics and genetic polymorphisms in the Asian population. We aimed to investigate relationship between genetic polymorphism of SLCO1B1 and rifampicin exposure and its impact on clinical outcomes in Korean patients with active pulmonary TB. Methods From February 2016 to December 2019, patients with active pulmonary TB who were taking rifampicin for >1 week were prospectively enrolled. Serial or 1-time blood sampling was conducted to determine rifampicin concentrations. The genotype of 4 single nucleotide polymorphisms of SLCO1B1 was determined. To estimate the drug clearance and exposure, population pharmacokinetics analysis was conducted. Clinical outcomes such as time to acid-fast bacteria culture conversion, chest radiograph score changes from baseline, and all-cause mortality were also evaluated. The exposure among different SLCO1B1 genotype was compared and relationship between drug exposure and clinical outcomes were explored. Results A total of 105 patients (70 males and 35 females) were included in the final analysis. The mean age of patients was 55.4 years. The mean drug clearance and exposure were 13.6 L/h and 57.9 mg h/L, respectively. The genetic polymorphisms of SLCO1B1 were not related to rifampicin clearance or exposure. As the rifampicin exposure increased, the chest radiographs improved significantly, but the duration of acid-fast bacteria culture conversion was not related to the drug exposure. Conclusion SLCO1B1 gene polymorphisms did not influence rifampicin concentrations and clinical outcomes in Korean patients with active pulmonary TB.

Since the 2008 Global Financial Crisis, financialization and housing speculation have expanded in geography, generalized in the political economy, and ingrained into the regulatory system. This art...

Background Amoxicillin/clavulanate is a widely used oral formulation of penicillin combined with a β-lactamase inhibitor. When using amoxicillin/clavulanate in the elderly, the risk of adverse drug reaction may be greater. This study aimed to evaluate the pharmacokinetics (PKs) and safety of multiple-dose amoxicillin/clavulanate administration in healthy elderly subjects and to compare the observed PK profiles with those in healthy younger adults. An open-label, one-sequence, multiple administration study was conducted in 16 healthy elderly subjects. Materials and methods Subjects orally received amoxicillin and clavulanate 750/187.5 twice daily for 9 days. For PK analysis, serial blood samples were collected up to 12 hours after the last administration of amoxicillin/clavulanate. The demographic and PK data of this study were compared to those of healthy young adults from a separate study with a similar design. Safety assessments including clinical laboratory tests, physical examination, vital signs, and adverse event (AE) monitoring were performed throughout the study. Results All AEs were mild, and no serious AEs were reported in this study. The systemic exposure of amoxicillin and clavulanate was ~ 90% and 60% higher, respectively, in the elderly subjects than in the younger subjects. However, the time required to reach maximum concentration at steady state and the elimination half-life were similar in the two age groups. Conclusion Although multiple administration of amoxicillin/clavulanate 750/187.5 mg was safe and well-tolerated, the systemic exposure of amoxicillin and clavulanate was higher in elderly subjects than in younger subjects.

OBJECTIVE To investigate the symptom deterioration of patients with benign prostatic hyperplasia (BPH) according to the difference in daily temperature. PATIENTS AND METHODS From the National Health Insurance Service database, we collected and analyzed data on patients with BPH in 6 major metropolitan areas in Korea between January 2008 and December 2017. We investigated the rate of emergency room visits as well as the rate of urethral catheter insertion. RESULTS In total, 1,446,465 patients were enrolled in this study. When the daily temperature difference was below 4°C, 28.5 patients visited the emergency room daily, while 42.2 patients visited the emergency room daily when the daily temperature difference exceeded 14°C. When the daily temperature difference was more than 14°C, about 48.0% more patients visited the emergency room than when the daily temperature difference was below 4°C. After visiting the emergency room, there were 11.9 patients who had a catheter inserted daily at the daily temperature difference below 4°C. When the daily temperature difference was more than 14°C, the number of catheter insertion cases was 17.8 patients daily, which was 49.2% higher than that of below 4°C. By time, surgery was performed most frequently within 3 months after visiting the emergency room. CONCLUSION Day temperature difference appear to be related to the Lower urinary tract symptom of BPH patients.

Acid-reducing agents are commonly used for the prevention of aspirin-induced gastrointestinal complications such as peptic ulcers. As a novel potassium-competitive acid blocker, fexuprazan is expected to prevent aspirin-induced gastrointestinal complications. This randomized, open-label study aimed to evaluate the pharmacodynamic and pharmacokinetic interactions between aspirin and fexuprazan in healthy Koreans. Subjects randomized to the aspirin group received 500 mg aspirin in combination with 80 mg fexuprazan. For the fexuprazan group, fexuprazan 80 mg was administered alone and then in combination with aspirin 500 mg. Platelet aggregation inhibited by aspirin and the pharmacokinetic parameters of aspirin and fexuprazan were compared between monotherapy and combination therapy. A total of 22 subjects completed the study. The platelet aggregation-inhibitory activity and systemic exposure to aspirin were not significantly affected by fexuprazan coadministration. The systemic exposure of fexuprazan was decreased up to 20% by aspirin coadministration, which was not regarded as clinically meaningful considering the previously reported exposure–response relationship. In conclusion, there were no clinically relevant pharmacodynamic or pharmacokinetic interactions between aspirin and fexuprazan. This finding suggests the potential of fexuprazan for the prevention of aspirin-induced gastrointestinal complications, serving as a baseline for optimizing its therapeutic application with aspirin.

Purpose: This study was aimed at determining the intraocular pharmacokinetics based on molecular physicochemical properties in a rabbit model. Methods: The entire dataset was obtained from previous literature, and research articles regarding 70 molecular compounds were investigated. The intravitreal half-lives in rabbit eyeballs of 22 macromolecules and 48 micromolecules were analyzed. Multiple linear regression analysis was carried out with non-collinear independent variables (molecular weight [MW] and lipophilicity) influencing intravitreal half-lives. The best-fit equations were selected based on the correlation coefficients and goodness-of-fit statistics. Results: The best-fit models obtained from the entire dataset, macromolecules, and micromolecules suggest the correlation between molecular physicochemical properties (MW and lipophilicity) and intravitreal half-life. Exclusion of outlier molecules (amphotericin B and foscarnet) leads to a better-fit correlation. MW is the definite single factor affecting intravitreal half-lives of macromolecules (Log t1/2 = 0.148 + 0.370 Log MW, R2 = 0.769), while both MW and lipophilicity influence the intraocular pharmacokinetics of micromolecules (Log t1/2 = –1.213 + 0.762 Log MW – 0.115 Log p, R2 = 0.554). Conclusion: The present study indicates that intravitreal half-life could be predicted based on molecular physicochemical properties (MW and lipophilicity). Also, increasing MW while reducing lipophilicity would be a reliable method for prolonging the intravitreal half-life of small chemical drugs, while MW is the single major determinant for large biologic drugs.

Ursodeoxycholic acid (UDCA) is a secondary bile acid component used for treating primary biliary cirrhosis. This study evaluated and compared the pharmacokinetic (PK) profiles of UDCA and its conjugates glyco-UDCA (G-UDCA) and tauro-UDCA (T-UDCA) in healthy elderly subjects and younger adults. In this randomized, open-label, 2-treatment, 1-sequence, and parallel study, subjects received 400 or 800 mg UDCA on day 1, followed by 200 mg UDCA twice daily for 2 weeks. Blood samples were obtained up to 24 hours after the first UDCA dose. Changes in miRNA-122, γ-glutamyl transferase, aspartate aminotransferase, and alanine aminotransferase levels from baseline were assessed to determine the safety and pharmacological effects of UDCA. This study examined the outcomes of 16 elderly subjects and 16 younger adults. Dose-normalized peak concentration of and systemic exposure to UDCA were 2 to 4 times higher, and the corresponding values of G-UDCA and T-UDCA were 1.7 times higher in the elderly subjects than in the younger adults. The subjects in both groups showed multiple peak profiles of UDCA and its conjugates. The miRNA-122 levels and hepatic enzyme test results were within the normal range in the elderly subjects after multiple administration of UDCA. This study is the first to confirm that the PK measurements of UDCA were higher in elderly subjects than in younger adults, which may improve the clinical outcomes of elderly subjects.

Aims: The aim of this study was to evaluate the safety/tolerability, and pharmacokinetics (PKs) of rhEGF eyedrops after administration of a single and multiple doses in healthy subjects. Methods: A phase 1, randomized, double-blind, placebo-controlled, and single ascending dose (SAD) and multiple ascending dose (MAD) study were conducted in 3 dose groups (10, 50, and 100 μg/mL). The subjects randomly received rhEGF eyedrops or their placebo in a 3:1 ratio. Serial blood and tear samples for PK analysis were collected up to 36 h and 180 h post-dose in SAD and MAD study, respectively. In addition, the serum and tear EGF concentrations were measured. Immunogenicity evaluations were conducted using serum anti-EGF antibody level. Results: A total of 50 subjects were enrolled and 48 subjects completed the study. Adverse drug reactions were mild and transient. There were no serious adverse events in this study. The tear EGF concentrations rapidly increased and returned to baseline after 4 hours without serum EGF level change after the administration of rhEGF eyedrops. Conclusion: rhEGF eyedrops were safe and well-tolerated in healthy subjects in a dose range of 10-100 μg/mL, which indicated it was suitable for further studies for corneal injury patients.

Aims Although metformin has been reported to affect the gut microbiome, the mechanism has not been fully determined. We explained the potential underlying mechanisms of metformin through a multiomics approach. Methods An open-label and single-arm clinical trial involving 20 healthy Korean was conducted. Serum glucose and insulin concentrations were measured, and stool samples were collected to analyze the microbiome. Untargeted metabolomic profiling of plasma, urine, and stool samples was performed by GC-TOF-MS. Network analysis was applied to infer the mechanism of the hypoglycemic effect of metformin. Results The relative abundances of Escherichia, Romboutsia, Intestinibacter, and Clostridium were changed by metformin treatment. Additionally, the relative abundances of metabolites, including carbohydrates, amino acids, and fatty acids, were changed. These changes were correlated with energy metabolism, gluconeogenesis, and branched-chain amino acid metabolism, which are major metabolic pathways related to the hypoglycemic effect. Conclusions We observed that specific changes in metabolites may affect hypoglycemic effects through both pathways related to AMPK activation and microbial changes. Energy metabolism was mainly related to hypoglycemic effects. In particular, branched-chain amino acid metabolism and gluconeogenesis were related to microbial metabolites. Our results will help uncover the potential underlying mechanisms of metformin through AMPK and the microbiome.

Several classes of antibiotics have reduced the mortality caused by infectious diseases; however, orally administered antibiotics alter the composition of gut microbiota, leading to dysbiosis-related disease. Therefore, in this study, we used 16S rRNA gene sequencing- and metabolomics-based approaches to investigate the effects of oral vancomycin on gut bacterial microbiota and the metabolome in biospecimens collected from healthy men. Samples collected from 11 healthy men were analyzed using 16S rRNA gene sequencing and metabolomics. 16S rRNA gene sequencing was performed to analyze the gut bacterial microbiota, and GC-TOFMS-based untargeted metabolomics was performed to analyze fecal, urine, and plasma metabolomics. Spearman’s rank correlation was utilized to explore the associations between gut bacterial microbiota and metabolome. Fecal 16S rRNA gene sequencing analysis showed decreased relative abundance of genera belonging to the phyla Bacteroidetes and Firmicutes, and increased relative abundance of genera of the phyla Proteobacteria and Fusobacteria. Fecal metabolomics analysis showed that levels of uracil, L-aspartic acid, lithocholic acid, and deoxycholic acid were significantly higher at baseline, whereas that of dihydrouracil was significantly higher after vancomycin administration. No significant metabolic markers were selected from urine and plasma metabolomics analysis. This study demonstrates that oral vancomycin administration induces alterations in gut bacterial microbiota and metabolome. Correlation analysis between our two datasets shows that alteration of the gut bacterial microbiota, induced by oral vancomycin, potentially affected the systemic activity of dihydropyrimidine dehydrogenase. This correlation should be further examined in future studies to define the effects of gut bacterial microbiota on drug-metabolizing enzymes, thereby contributing to the development of personalized therapy.

Sorafenib, an oral multikinase inhibitor, exhibits a highly variable absorption profile due to enterohepatic reabsorption and poor solubility. SYO-1644 improved the solubility of sorafenib by nanoparticulation technology leading to enhanced bioavailability. To evaluate the pharmacokinetically equivalent dose of SYO-1644 to the reference Nexavar® 200 mg, a randomized, open-label, replicated two-period study was conducted in healthy volunteers. A total of 32 subjects orally received a single dose of the following assigned treatment under a fasted state in the first period and repeated once more in the second period with a two-week washout: SYO-1644 100, 150 and 200 mg and Nexavar® 200 mg. Pharmacokinetic (PK) samples were collected up to 168 h post-dose. The PK profile was evaluated by both non-compartmental analysis and population PK method. With the final model, 2 × 2 crossover trial scenarios with Nexavar® 200 mg and each dose of SYO-1644 ranging from 100 to 150 mg were repeated 500 times by Monte Carlo simulation, and the proportion of bioequivalence achievement was assessed. Transit absorption compartments, followed by a one-compartment model with first-order elimination and enterohepatic reabsorption components were selected as the final model. The simulation results demonstrated that the SYO-1644 dose between 120 and 125 mg could yielded the highest proportion of bioequivalence.

Background A vancomycin loading dose is recommended for the treatment of serious methicillin-resistant Staphylococcus aureus (MRSA) infections. However, clinicians often do not adhere to these recommendations, mainly due to nephrotoxicity risk, unfamiliarity with the guideline, or complexity of calculating an individual dose. Therefore, we introduced a computerised clinical decision support system (CDSS) for vancomycin loading (hereafter Vancomycin CDSS) to promote the use of vancomycin loading dose. Methods We describe a quasi-experimental study spanning 6 months before and 18 months after the deployment of a Vancomycin CDSS. The Vancomycin CDSS was integrated into the hospital’s electronic medical record system in the form of a vancomycin order set. Our primary endpoint was the incidence of nephrotoxicity; the secondary endpoint was mean initial vancomycin trough levels. We also conducted a survey to evaluate the reasons why clinicians opted not to utilise a vancomycin loading dose. Results After implementation of Vancomycin CDSS, 363 out of 746 patients (49 %) who were first administered vancomycin received a loading dose. We did not find significant differences in nephrotoxicity between the pre- and post-intervention groups, nor between the loading- and non-loading groups. In the pre-intervention group, the mean initial vancomycin trough level was 7.10 mg/L, which was significantly lower than that in the post-intervention group of 11.11 mg/L. In the vancomycin loading group, the mean initial trough level was 11.95 mg/L, compared to 7.55 mg/L in the non-loading group. The main reason stated for not prescribing a vancomycin loading dose was concern about nephrotoxicity. Conclusion Introduction of the Vancomycin CDSS did not increase nephrotoxicity and increased the mean initial dose and trough level of vancomycin.

Purpose To investigate the intraocular distribution and kinetics of antibodies and nanoparticles in the experimental model. Methods Antibodies (whole IgG 149kDa, antigen-binding fragments 48.39 kDa) and four kinds of nondegradable nanoparticles (25, 50, 200, and 250 nm) were intravitreally injected in the right eye of New Zealand white rabbits. The average optical density and concentration were used to measure intraocular distribution and kinetics. Results After intravitreal injection, antibodies were distributed throughout the vitreous humor and eliminated gradually into anterior and posterior routes. Fluorescence intensity decreased 1 day after injection and was not detected 25 days after injection. The nondegradable nanoparticles migrated posteriorly to the retina 7 days after injection onward and anteriorly to the aqueous humor from 1 hour to 1 day after injection. The fluorescence intensity of the nanoparticles was relatively stable in the vitreous humor, compared to antibodies. Nanoparticles accumulated on the internal limiting membrane of the retina with no penetration into deeper retinal tissue, whereas the smaller size 25 nm nanoparticles passed across the ciliary body and moved into choroid, retina, and suprachoroidal space. A gradual decrease of nanoparticles by their sizes in the vitreous after 30 days after injection was described as the percentage ratio: 61.1% (25 nm), 69.1% (50 nm), 78.6% (200nm), and 85.3% (250 nm). Conclusions Our study revealed the in vivo intraocular distribution and kinetics of antibodies and nanoparticles with diverse sizes and the result might help to develop newer intraocular drugs and drug delivery systems to treat retinal diseases. Translational relevance These experimental results can be valuable data for human research.

INTRODUCTION AND OBJECTIVE:To predict the prognosis of localized prostate cancer (PCa) patients and evaluate the actual contribution of tumor volume (TV) to the prognosis of PCa.METHODS:We prospect...

Organic cation transporter 3 (OCT3) is expressed in various organs in humans and plays an important role in the transport of organic cations and drugs including metformin. In this study, we identified genetic variations of the OCT3 promoter and functionally characterized each variant by in vitro assays. Next, the association between the functional haplotype of the OCT3 promoter and pharmacokinetics of metformin was evaluated. In our study population, 7 variations and 2 major haplotypes were identified, of which H2 haplotype yielded a significantly higher luciferase activity than did the wild type. Two variants of H2, c.-1603G > A and c.-1547T > G, yielded significantly lower luciferase activities, whereas the luciferase activity of another variant, c.-29G > A, was significantly higher. Two transcription factors, Sp1 and USF1, were involved in the regulation of OCT3 transcription. Analysis of clinical data revealed that 25 subjects, either homozygous or heterozygous for H2, showed increased AUCinf and Cmax by 17.2% and 15.9%, respectively [P = 0.016 and 0.031, GMR (90% CI) = 1.17 (1.06–1.29) and 1.17 (1.04–1.31), respectively], compared to the 20 subjects in the control group. Our study suggests that an OCT3 promoter haplotype affects the pharmacokinetics of metformin in Koreans as well as the OCT3 transcription rate.

Combination therapy of pregabalin and tramadol is used to treat chronic neuropathic pain; however, the pharmacokinetic (PK) interactions of these drugs has not been studied. This study aimed to evaluate PK interactions between pregabalin and tramadol and the safety of combination therapy. A randomized, open-label, multiple-dose, three-treatment, three-period, six-sequence cross-over study was conducted in healthy subjects. All subjects received the following three treatments for 4 days in each period: pregabalin 150 mg twice daily; tramadol extended-release (ER) 200 mg in the morning, and 100 mg in the evening; and co-administration of pregabalin 150 mg and tramadol ER 200 mg in the morning, and pregabalin 150 mg and tramadol ER 100 mg in the evening. A total of 21 subjects completed the study with no clinically significant safety issues. For pregabalin, the geometric mean ratio (GMR) (90% CI; confidence interval) of combination therapy to monotherapy for maximum concentration at steady state (Cmax,ss) and area under the concentration curve from 0 to dosing interval time at steady state (AUCτ,ss) were 0.8801 (0.8043–0.9632) and 1.0830 (1.0569–1.1098), respectively. The corresponding values for tramadol were 1.0177 (0.9839–1.0526) and 1.0152 (0.9896–1.0414), respectively. The GMR (90% CI) of combination therapy to monotherapy of O-desmethyl-tramadol for Cmax,ss and AUCτ,ss was 1.0465 (1.0095–1.0848) and 1.0361 (1.0001–1.0734), respectively. There were no significant drug interactions between pregabalin and tramadol, considering that all of the 90% CI of PK measures were within the conventional bioequivalence range. Both drugs were well tolerated when administered concomitantly.

Jung Sunwoo,1 Yu Kyong Kim,1 Yewon Choi,1 Kyung-Sang Yu,1 Heesook Nam,2 Young Lag Cho,2 Seonghae Yoon,3 Jae-Yong Chung3 1Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Hospital, Seoul, 2LegoChem Biosciences, Inc., Daejeon, 3Department of Clinical Pharmacology and Therapeutics, Seoul National University College of Medicine and Bundang Hospital, Seongnam, Republic of Korea Background: LCB01-0371 is a novel oxazolidinone antibiotic that blocks protein production by binding to bacterial 23S ribosomes. This antibiotic is active against Gram-positive bacteria. This study aimed to evaluate the effect of food on the pharmacokinetics (PKs) of LCB01-0371 and evaluate its safety profile.Subjects and methods: A randomized, open-label, two-way crossover study was performed in 18 healthy Korean male subjects. All subjects received a single oral 800mg dose of LCB01-0371 in each period under fed or fasting condition with a 7-day washout in between. The fed condition was defined as consumption of a meal of 800–1,000kcal containing ~50% of fat content. Serial blood samples were collected over 24h after dosing, and the PK parameters were calculated by noncompartment analysis. All available data of the subjects who received LCB01-0371 at least once were included in the safety data summaries.Results: In the fed condition, both the maximum plasma concentration (Cmax) and the total systemic exposure (area under the plasma concentration–time curve from time zero to the last observed time point [AUClast]) decreased by ~33% and 10%, respectively. The time to reach Cmax was delayed by ~1.25h in the fed condition, whereas the mean elimination half-life remained similar in both conditions. In the fed/fasting condition, the geometric mean ratios and 90% CI of the Cmax and AUClast were 0.666 (0.470–0.945) and 0.897 (0.761–1.057), respectively. There were no drug-related adverse events (AEs) or serious AEs.Conclusion: Although the Tmax after a single oral 800mg dose of LCB01-0371 was slightly delayed under the fed condition compared to the fasting condition, the total systemic exposure was similar under both conditions. Therefore, LCB01-0371 could be administered regardless of food intake. Keywords: antibiotic resistance, gram-positive bacteria, clinical trial

Metformin, an oral hypoglycemic agent belonging to biguanide class, is widely used to treat type 2 diabetes mellitus, and several drug transporters such as organic cation transporters (OCTs), multidrug and toxin extrusion transporter (MATE), and plasma membrane monoamine transporter (PMAT) are thought to affect its disposition. We evaluated the role of PMAT genetic variations on the pharmacokinetic characteristics of metformin in a Korean population. In this retrospective study, 91 healthy subjects from four different metformin pharmacokinetic studies were analyzed; in each study, the subjects were administered two oral doses of metformin at intervals of 12 hours and dose-normalized pharmacokinetic parameters were compared between the subjects' genotypes. Subjects who had more than one allele of c.883-144A>G single nucleotide polymorphism (SNP) in PMAT gene (rs3889348) showed increased renal clearance of metformin compared to wild-type subjects (814.79 ± 391.73 vs. 619.90 ± 195.43 mL/min, p=0.003), whereas no differences in metformin exposure were observed between the PMAT variant subjects and wild-type subjects. Similarly, subjects with variant rs316019 SNP in OCT2 showed decreased renal clearance of metformin compared to wild-type subjects (586.01 ± 160.54 vs. 699.13 ± 291.40 mL/min, p=0.048). Other SNPs in PMAT and MATE1/2-K genes did not significantly affect metformin pharmacokinetics. In conclusion, the genetic variation of c.883-144A>G SNP in PMAT significantly affects the renal clearance of metformin in healthy Korean male subjects.

We developed linearly linked spherical fillers in polymer composites with incorporating Al2O3-Fe3O4 hybrid particles under a magnetic field to form thermal networks for high thermal conductivity. The Al2O3-Fe3O4 hybrid particles were prepared by a simple precipitation method and their magnetic properties were characterized with magnetic hysteresis. The Al2O3-Fe3O4 hybrid particles were well aligned through direction of magnetic field as confirmed by microscopic observation. The polymer composites obtained with Al2O3-Fe3O4 hybrid particles possessed high thermal conductivity in a parallel magnetic alignment direction at low filler loading, which is more than 240% outperformed the composites with randomly dispersed fillers.

Background LCB01-0371 is a new oxazolidinone antibiotic, which targets most Gram-positive organisms. High rates of adverse reactions including myelosuppression have been reported for existing oxazolidinones, limiting their long-term use. Objectives The safety, tolerability and pharmacokinetics (PK) of 21 day multiple oral administrations of LCB01-0371 in healthy male subjects (clinicaltrials.gov: NCT02540460) were investigated. Methods In this randomized, double-blind, placebo-controlled study, subjects received 800 mg of LCB01-0371 once or twice daily or 1200 mg of LCB01-0371 twice-daily for 21 days in a fasting state. Safety and tolerability profiles including laboratory tests were evaluated during the study and on a post-study visit and the results were analysed using repeated-measures analysis of variance (RM-ANOVA). Serial blood samples for PK analysis were collected up to 12 h after dosing on day 21. Results A total of 40 subjects were enrolled and 34 subjects completed the study. Two subjects dropped out according to stopping rules. In the 1200 mg twice-daily dose group, the absolute value of red blood cell count, haematocrit and haemoglobin decreased by 500 × 106/L (6.5%), 4.5% (6.8%) and 1.6 g/dL (6.9%), respectively, after 21 day administrations of LCB01-0371. However, mean relative changes from baseline of all haematology values were not significantly different among doses, including placebo (all, P