Exposure to Multiwall Carbon Nanotubes Promotes Fibrous Proliferation by Production of Matrix Metalloproteinase-12 via NF-κB Activation in Chronic Peritonitis.

The toxicologic effects of nanomaterials, such as carbon nanotubes (CNTs), on the immune system are understood well. However, the precise relationship between long-term exposure to CNTs and chronic inflammation remains unclear. In this study, a mouse model of chronic peritonitis was established using i.p. injection of multiwalled CNTs treated by the Taquann method with high dispersion efficiency. Chronic peritonitis with fibrosis was observed in Taquann-treated multiwalled CNT (T-CNT)-injected mice, but not in Taquann-treated titanium dioxide-injected mice. In vivo and in vitro experiments showed that matrix metalloproteinase-12 (MMP-12) of macrophages was up-regulated by T-CNT to enhance fibroblast activation and profibrotic molecule expression in fibroblasts. In addition, T-CNT-induced peritonitis reduced MMP-12 expression in Nfκb1-/- mice, suggesting that MMP-12-producing macrophages play a key role in chronic inflammation due to T-CNT exposure through NF-κB activation. The results of this study could be helpful in understanding the molecular toxicity of nanomaterial and chronic inflammation.

Achaete-Scute Homologue 2-Regulated Follicular Helper T Cells Promote Autoimmunity in a Murine Model for Sjögren Syndrome.

Follicular helper T (Tfh) cells contribute to various immune responses as well as to the pathogenesis of several immune diseases. However, the precise mechanism underlying the onset or development of autoimmunity via Tfh cells remains unclear. Herein, the detailed relationship between autoimmune disease and Tfh cells was analyzed using a murine model for Sjögren syndrome (SS) wherein the mice underwent neonatal thymectomy. Germinal center (GC) development was promoted in this SS model along with an increase of Tfh cells and GC B cells. The severity of the autoimmune lesions was correlated with the number of Tfh cells detected in the spleen of the SS model mice. In addition, treatment with an anti-CD20 monoclonal antibody effectively suppressed the autoimmune lesions with a reduction of Tfh cells and GC B cells. Comprehensive gene analysis revealed that several genes associated with Tfh cell differentiation, including achaete-scute homologue 2 (Ascl2), were up-regulated in peripheral CD25- CD4+ T cells in SS model mice compared with those in control mice. Moreover, an experiment using CD4CreBcl6fl/fl mice that received neonatal thymectomy treatment demonstrated that Ascl2 contributes to the Tfh cell differentiation associated with autoimmunity during the early stages, independent of Bcl6. In conclusion, our results indicate that abnormal Tfh cell differentiation via Ascl2 regulation might contribute to the pathogenesis of autoimmunity.

Pharmacokinetic and pharmacodynamic modelling for renal function dependent urinary glucose excretion effect of ipragliflozin, a selective sodium-glucose cotransporter 2 inhibitor, both in healthy subjects and patients with type 2 diabetes mellitus.

AIMS: To provide a model-based prediction of individual urinary glucose excretion (UGE) effect of ipragliflozin, we constructed a pharmacokinetic/pharmacodynamic (PK/PD) model and a population PK model using pooled data of clinical studies. METHODS: A PK/PD model for the change from baseline in UGE for 24 hours (ΔUGE24h ) with area under the concentration-time curve from time of dosing to 24 h after administration (AUC24h ) of ipragliflozin was described by a maximum effect model. A population PK model was also constructed using rich PK sampling data obtained from 2 clinical pharmacology studies and sparse data from 4 late-phase studies by the NONMEM $PRIOR subroutine. Finally, we simulated how the PK/PD of ipragliflozin changes in response to dose regime as well as patients' renal function using the developed model. RESULTS: The estimated individual maximum effect were dependent on fasting plasma glucose and renal function, except in patients who had significant UGE before treatment. The PK of ipragliflozin in type 2 diabetes mellitus (T2DM) patients was accurately described by a 2-compartment model with first order absorption. The population mean oral clearance was 9.47 L/h and was increased in patients with higher glomerular filtration rates and body surface area. Simulation suggested that medians (95% prediction intervals) of AUC24h and ΔUGE24h were 5417 (3229-8775) ng·h/mL and 85 (51-145) g, respectively. The simulation also suggested a 1.17-fold increase in AUC24h of ipragliflozin and a 0.76-fold in ΔUGE24h in T2DM patients with moderate renal impairment compared to those with normal renal function. CONCLUSIONS: The developed models described the clinical data well, and the simulation suggested mechanism-based weaker antidiabetic effect in T2DM patients with renal impairment.

Efficacy and safety of 3-month dosing regimen of degarelix in Japanese subjects with prostate cancer: A phase III study.

Non-inferiority in the cumulative castration rate of the 3-month formulation of degarelix compared with the 3-month formulation of goserelin was evaluated in subjects with prostate cancer. A phase III, open-label, parallel-arm study was carried out. An initial dose of 240 mg degarelix or 3.6 mg goserelin was given s.c.; after day 28, a maintenance dose of 480 mg degarelix or 10.8 mg goserelin was given once every 84 days. Non-inferiority in castration rate and safety of degarelix to goserelin were evaluated. The primary end-point was the cumulative castration rate from day 28 to day 364 and the non-inferiority margin was set to be 10%. A total of 234 subjects with prostate cancer were randomized to the degarelix group (n = 117) and the goserelin group (n = 117). The cumulative castration rate was 95.1% in the degarelix group and 100.0% in the goserelin group. As there were no events in the goserelin group, an additional analysis was carried out using 95% confidence intervals of the difference in the proportion of subjects with castration. Analyses indicated the non-inferiority of the 3-month formulation of degarelix to goserelin. Degarelix showed more rapid decreases in testosterone, luteinizing hormone, follicle stimulating hormone, and prostate-specific antigen levels compared with goserelin. The most common adverse events in the degarelix group were injection site reactions. Non-inferiority of the 3-month formulation of degarelix to goserelin was shown for testosterone suppression. The 3-month formulation of degarelix was also found to be tolerated as an androgen deprivation therapy for patients with prostate cancer. This trial was registered with ClinicalTrials.gov (identifier NCT01964170).

A rare male patient with classic Rett syndrome caused by MeCP2_e1 mutation.

Rett syndrome (RTT) is a severe neurodevelopmental disorder typically affecting females. It is mainly caused by loss-of-function mutations that affect the coding sequence of exon 3 or 4 of methyl-CpG-binding protein 2 (MECP2). Severe neonatal encephalopathy resulting in death before the age of 2 years is the most common phenotype observed in males affected by a pathogenic MECP2 variant. Mutations in MECP2 exon 1 affecting the MeCP2_e1 isoform are relatively rare causes of RTT in females, and only one case of a male patient with MECP2-related severe neonatal encephalopathy caused by a mutation in MECP2 exon 1 has been reported. This is the first reported case of a male with classic RTT caused by a 5-bp duplication in the open-reading frame of MECP2 exon 1 (NM_001110792.1:c.23_27dup) that introduced a premature stop codon [p.(Ser10Argfs*36)] in the MeCP2_e1 isoform, which has been reported in one female patient with classic RTT. Therefore, both males and females displaying at least some type of MeCP2_e1 mutation may exhibit the classic RTT phenotype.

Acceleration of tumor growth due to dysfunction in M1 macrophages and enhanced angiogenesis in an animal model of autoimmune disease.

Both autoimmunity and tumor immunity are immune responses against self-tissues or cells. However, the precise similarity or difference between them remains unclear. In this study, to understand a novel mechanism of tumor immunity, we performed transplantation experiments with a murine autoimmune model, C57BL/6J (B6)/lpr mice. A melanoma cell line, B16F10 cells, or granulocyte macrophage colony-stimulating factor- overexpressing B16F10 (B16F10/mGM) cells were transplanted into B6 or B6/lpr mice. Tumor growth by transplanted B16F10/mGM cells was significantly accelerated in B6/lpr mice compared with that in B6 mice. The accumulation of M1 macrophages in the tumor tissues of B6/lpr recipient mice was significantly lower compared with that in the control mice. In vitro co-culture experiment showed that impaired differentiation into M1 macrophages was observed in B6/lpr mice. The number of tumor vessels and vascular endothelial growth factor (VEGF) expression were also significantly enhanced in the tumor tissues of B6/lpr mice compared with those in the B6 mice. Moreover, VEGF expression was correlated with the increased expression of hypoxia-inducible factor-1α in the tumor tissues of B6/lpr mice. These results suggest that dysfunctional tumor immunity and enhanced angiogenesis in autoimmunity influence tumor growth.

Identification of 2-[2-(4-tert-Butylphenyl)ethyl]-N-[4-(3-cyclopentylpropyl)-2-fluorophenyl]-1,2,3,4-tetrahydroisoquinoline-6-sulfonamide as an Orally Active MGAT2 Inhibitor.

We previously reported 2-[2-(4-tert-butylphenyl)ethyl]-N-(4-fluorophenyl)-1,2,3,4-tetrahydroisoquinoline-6-sulfonamide 2 as on orally available monoacylglycerol acyltransferase 2 (MGAT2) inhibitor which exhibited an in vivo efficacy at an oral dose of 100 mg/kg in a mouse oral lipid tolerance test. Further optimization of compound 2 to improve the intrinsic potency culminated in the identification of compound 11. Compound 11 showed a >50-fold lower IC50 against human MGAT2 enzyme than 2. Oral administration of 11 at a dose of 3 mg/kg in the oral lipid tolerance test resulted in significant suppression of triglyceride synthesis.

Molecular Mechanisms of Nickel Allergy.

Allergic contact hypersensitivity to metals is a delayed-type allergy. Although various metals are known to produce an allergic reaction, nickel is the most frequent cause of metal allergy. Researchers have attempted to elucidate the mechanisms of metal allergy using animal models and human patients. Here, the immunological and molecular mechanisms of metal allergy are described based on the findings of previous studies, including those that were recently published. In addition, the adsorption and excretion of various metals, in particular nickel, is discussed to further understand the pathogenesis of metal allergy.

Identification of 2-[2-(4-tert-butylphenyl)ethyl]-N-(4-fluorophenyl)-1,2,3,4-tetrahydroisoquinoline-6-sulfonamide (29) as an orally available MGAT2 inhibitor.

MGAT2 (monoacylglycerol acyltransferase 2) is expected to be an attractive target for the drug treatment of obesity, diabetes, and other disease. We describe our exploration and structure-activity relationship (SAR) study of 2,3-dihydro-1H-isoindole-5-sulfonamide derivatives. In this study, we identified 29 as an orally available inhibitor of MGAT2 through optimization especially in terms of solubility. This compound exhibited moderate potency in the enzyme inhibitory assay (IC50 = 1522 nM) and significant suppression of fat absorption (57% inhibition) in mice oral lipid tolerance test.

Population Pharmacokinetic Modeling and Simulation of Pudexacianinium (ASP5354) for Dose Setting of a Phase 2 First-in-Patient Study: A Novel Imaging Agent for Intraoperative Ureter Visualization during Abdominopelvic Surgery.

Pudexacianinium (ASP5354) chloride is an indocyanine green derivative designed to enable enhanced ureter visualization during surgery. The objective of the present analysis was to determine appropriate doses of pudexacianinium for a phase 2, dose-ranging study (NCT04238481). Real-time urine pudexacianinium concentration is considered a good pharmacodynamic surrogate marker, since ureter visualization likely depends on its concentration in the ureter. Using plasma and urine concentrations of pudexacianinium from a phase 1 single-ascending-dose (0.1-24.0 mg) study in healthy participants, a 3-compartment population pharmacokinetic model with a urine output compartment was developed and effectively described the concentration-time profiles. The individual estimated glomerular filtration rates had a significant impact on drug clearance. Simulations suggested that a 1.0 mg intravenous injection would achieve target urine concentrations over 1 µg/mL (determined from previous nonclinical studies) for 3 hours postdose, assuming a urine production rate of 1.0 mL/min. Based on this simulation, doses of 0.3, 1.0, and 3.0 mg were proposed for the phase 2 study. The observed plasma concentrations were generally consistent with model predictions. For urine, although only limited data could be obtained due to the difficulties of spot urine collection from surgical patients, intraoperative ureter visualization was successful at 1.0 and 3.0 mg.

Dominant-negative mutations in the DNA-binding domain of STAT3 cause hyper-IgE syndrome.

Hyper-immunoglobulin E syndrome (HIES) is a compound primary immunodeficiency characterized by a highly elevated serum IgE, recurrent staphylococcal skin abscesses and cyst-forming pneumonia, with disproportionately milder inflammatory responses, referred to as cold abscesses, and skeletal abnormalities. Although some cases of familial HIES with autosomal dominant or recessive inheritance have been reported, most cases of HIES are sporadic, and their pathogenesis has remained mysterious for a long time. Here we show that dominant-negative mutations in the human signal transducer and activator of transcription 3 (STAT3) gene result in the classical multisystem HIES. We found that eight out of fifteen unrelated non-familial HIES patients had heterozygous STAT3 mutations, but their parents and siblings did not have the mutant STAT3 alleles, suggesting that these were de novo mutations. Five different mutations were found, all of which were located in the STAT3 DNA-binding domain. The patients' peripheral blood cells showed defective responses to cytokines, including interleukin (IL)-6 and IL-10, and the DNA-binding ability of STAT3 in these cells was greatly diminished. All five mutants were non-functional by themselves and showed dominant-negative effects when co-expressed with wild-type STAT3. These results highlight the multiple roles played by STAT3 in humans, and underline the critical involvement of multiple cytokine pathways in the pathogenesis of HIES.

Effect of food on the pharmacokinetics of darexaban, an oral direct factor Xa inhibitor, in healthy Japanese subjects.

BACKGROUND: Darexaban is a potent direct factor Xa (FXa) inhibitor developed for prophylaxis of venous and arterial thromboembolic disease. This drug is rapidly and extensively metabolized to darexaban glucuronide (YM-222714), which is a pharmacologically active metabolite. The potential effects of food on the harmacokinetics of darexaban glucuronide after darexaban administration were assessed in two studies. METHODS: Both studies were conducted as open-label, two-way crossover studies. Healthy non-elderly Japanese male subjects received darexaban as a single 15 mg tablet (Study 1, n = 24) or a single 30 mg tablet (Study 2, n = 24). The geometric mean ratio (GMR) (fed/fasted) for AUClast and Cmax were evaluated as primary parameters. RESULTS: GMR(fed/fasted) for AUClast emonstrated slight decreases as 0.797 (90% CI: 0.758 - 0.838) in Study 1 and 0.821 (90% CI: 0.752 - 0.896) in Study 2. For Cmax, the GMR was 0.908 (90%CI: 0.835 - 0.988) in Study 1 and 1.039 (90% CI: 0.953 - 1.131) in Study 2. There were no serious adverse events during the two studies. None was considered to be drug-related. CONCLUSION: These studies demonstrated that there was no clinically significant effect of food on the pharmacokinetics after administration of darexaban. We therefore conclude that darexaban can be administered without regard to food intake.

Cutaneous manifestations of Hyper IgE syndrome.

Hyper-IgE syndrome (HIES) is a primary immunodeficiency disorder characterized by atopic manifestations and susceptibility to infections with extracellular bacteria and fungi. Atopic manifestations include atopic dermatitis-like skin lesion and extremely high serum IgE levels. Most of the extracellular bacterial infections are caused by Staphylococcus aureus, which is associated with milder inflammation compared to normal. Recent studies have revealed that the most cases of the HIES are caused by dominant negative mutations in STAT3 gene. Cutaneous manifestations of HIES includes newborn rash, eczematoid dermatitis, cold abscesses, mucocutaneous candidiasis, and coarse texture of the facial skin. Impaired Th17 cell development due to the defective IL-6 signaling in T cells and impaired induced regulatory T (iTreg) cell generation due to defective IL-10 signaling in dendritic cells may, at least in part, account for the cutaneous pathology of HIES.

Home visiting support for people with hikikomori (social withdrawal) provided by experienced and effective workers.

OBJECTIVES: Hikikomori - an almost complete withdrawal from social interaction first seen in Japan - is becoming an emerging psychological syndrome worldwide. The mental health community in Japan has focused on hikikomori since the 1990s. Hikikomori was initially considered a culture-bound trait, unique to Japan; however, it has become an international concern, and cases have been reported even outside of Japan. While home visiting support for people with hikikomori has gained popularity, an effective solution remains elusive. This paper describes the process involved in effective home visiting support provided by experienced workers to help people with hikikomori. METHOD: Semi-structured interviews were conducted with 21 home-visiting support workers in Japan. Collected data were analysed using a constant comparative method based on Grounded Theory. RESULTS: 'Supporting them in finding their own way to participate in society' was identified as the core category. This core category was substantiated by following three interrelated stages: preparing the involved surroundings for reaching out to a person, maintaining constant communication and expanding the range of activities and relationships. The process encouraged people with hikikomori to enhance their social connections and improved their motivation for social participation. People with hikikomori experiencing despair and isolation began to find pleasure in social participation through the three stages of support provided by home-visiting workers. CONCLUSION: Our study suggests that Home visiting support for people with hikikomori can be enhanced by these three interrelated methods which can help individuals integrate into society and connect with others.

Argan (Argania Spinosa) press cake extract enhances cell proliferation and prevents oxidative stress and inflammation of human dermal papilla cells.

BACKGROUND: Hair follicle undergoes a growth cycle under the regulation of dermal papilla cells. Due to their enormous roles, these fibroblast cells have been used in various in vitro studies as a screening model to evaluate the effect of hair growth regulating agents. OBJECTIVE: In the current study, we aim to check the hair growth potential effect of Argan press cake (APC) extracted using 50 or 80 % aqueous ethanol on human hair follicle dermal papilla cells (HFDPCs) and to determine the molecular mechanism. METHODS: APC were applied to HFDPCs, then cell proliferation assays, mitochondrial biogenesis assay, and oxidative stress assay were assessed. DNA microarray was performed from the cells treated with our samples and minoxidil. Validation of the results was done using Quantitative Real-Time PCR with primers for hair-growth related genes. GC/MS analysis was used to determine the compounds contained in APC 50 and 80 %. RESULTS: APC enhanced cell proliferation along with the stimulation of the ATP content. Additionally, APC had an anti-oxidant activity against H2O2 mediated oxidative stress preventing dermal papilla cell senescence. Consistent with this, global gene profiling analysis showed an activation of hair growth-related pathway, and a downregulation of inflammation- and oxidative stress-related genes by APC extracts. GC/MS analysis revealed that these extracts contained pure fatty acids, derived sugar chains, and pure compounds including tocopherols, squalene, and spinasterol. CONCLUSION: Taken together, here we showed that APC extracts had an effect on stimulating hair growth while inhibiting the inflammation and the oxidative stress of HFDPCs and thus can potentially contribute to an anti-hair loss drug development.

Functionally confirmed compound heterozygous ADAM17 missense loss-of-function variants cause neonatal inflammatory skin and bowel disease 1.

A disintegrin and metalloprotease 17 (ADAM17) is the major sheddase that processes more than 80 substrates, including tumour necrosis factor-α (TNFα). The homozygous genetic deficiency of ADAM17 causing a complete loss of ADAM17 expression was reported to be linked to neonatal inflammatory skin and bowel disease 1 (NISBD1). Here we report for the first time, a family with NISBD1 caused by functionally confirmed compound heterozygous missense variants of ADAM17, namely c.1699T>C (p.Cys567Arg) and c.1799G>A (p.Cys600Tyr). Both variants were detected in two siblings with clinical features of NISBD1, such as erythroderma with exudate in whole body, recurrent skin infection and sepsis and prolonged diarrhoea. In a cell-based assay using Adam10/17 double-knockout mouse embryonic fibroblasts (Adam10/17-/- mEFs) exogenously expressing each of these mutants, phorbol 12-myristate 13-acetate-stimulated shedding was strongly reduced compared with wild-type ADAM17. Thus, in vitro functional assays demonstrated that both missense variants cause the loss-of-function of ADAM17, resulting in the development of NISBD1. Our study further expands the spectrum of genetic pathology underlying ADAM17 in NISBD1 and establishes functional assay systems for its missense variants.

Fast decoloration of spironaphthooxazine bound to a poly(dimethylsiloxane) network.

Spironaphthooxazine (SNO) was attached to a three-dimensional network of polysiloxane through the allyloxy group on C-7 of the naphthalene ring of SNO, and the photochemical coloration and thermal decoloration behaviors of this material (Film-P) were examined by comparing their properties with those of model SNO having a 7-propyloxynaphthyl group in solution, in a doped polysiloxane film (Film-D), and in a doped PMMA film. For Film-P, the SNO units were connected to a part of the vinyl groups on the Si atoms of a linear polysiloxane by hydrosilylation, and the remaining vinyl groups were bridged by the bifunctional linear polysiloxane possessing two hydrosilyl groups at both ends of the chain. While Film-P containing 1.7 x 10(-3) mol dm(-3) of the SNO unit formed a transparent film, Film-D containing more than 1.2 x 10(-3) mol dm(-3) could not form a transparent film but segregation of SNO occurred. A transparent Film-D was prepared at 0.54 x 10(-3) mol dm(-3) SNO concentration. The decoloration reaction rate of Film-D was faster than those for Film-P, solutions, and PMMA. However, due to the low concentration, the coloration of Film-D was weak. When the concentration of SNO in Film-P was increased 5.7 times, the decoloration rate became 3.6 times faster. Its half-life time was 0.9 s, which is 3.1 times as fast as that of corresponding solution in hexamethyldisiloxane.

Population pharmacokinetics of R- and S-carvedilol in Japanese patients with chronic heart failure.

Carvedilol is a beta-adrenoceptor antagonist used for treating chronic heart failure (CHF). Two clinical studies were conducted to evaluate the population pharmacokinetics and pharmacodynamics of R- and S-carvedilol, and associated covariates, in patients with CHF. Fifty-eight patients (male=45, female=13) with New York Heart Association class I-IV CHF were enrolled in two clinical studies. R- and S-carvedilol concentrations were measured using HPLC at steady-state after oral administration of carvedilol at 1.25-20 mg o.d. or b.i.d. The data from both studies were used to estimate the population pharmacokinetic parameters and covariates using the nonlinear mixed effects model program. For 40 patients evaluated in one clinical study, the cytochrome P450 (CYP)2D6 *1, *10, and *5 genotypes were determined using allele-specific primer PCR, and individual patients' oral clearance (CL/F) of both enantiomers were estimated by the empirical Bayes method. A one-compartment model with a first-order absorption rate was established, in which body weight and alpha(1)-acid glycoprotein were significant covariates. Individual CL/F values for carvedilol were significantly lower in Japanese CHF patients with the CYP2D6 *1/*5, *5/*10 and *10/*10 genotypes. Estimation of the population pharmacokinetic parameters and their covariates for each enantiomer in Japanese patients with CHF showed that the CL/F values for R- and S-carvedilol were dependent on body weight, alpha(1)-acid glycoprotein, and CYP2D6 genotype. Prediction of exposure to free plasma carvedilol is important for dosage adjustment of beta-blocker therapy in patients with CHF.

Comparison of the Pharmacokinetic and Pharmacodynamic Relationship of Ipragliflozin Between Patients With Type 1 and Type 2 Diabetes Mellitus.

PURPOSE: To characterize the pharmacokinetic and pharmacodynamic (PK/PD) relationship of ipragliflozin in Japanese patients with type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) and to determine the appropriate dose regimen for a Phase III study of ipragliflozin in Japanese patients with T1DM. METHODS: The PK (AUC24h of plasma ipragliflozin) and PD (renal glucose clearance) properties in patients with T1DM and T2DM were assessed in 2 independent clinical pharmacologic studies of ipragliflozin. The same maximum efficacy (Emax) model described the PK/PD relationship in patients with T1DM and T2DM. Changes in fasting plasma glucose (FPG) in T1DM patients were simulated by applying a previously established FPG model for ipragliflozin in patients with T2DM. FINDINGS: Data from 42 patients with T1DM and 28 patients with T2DM were used. Comparable AUC24h of plasma ipragliflozin and similar dose dependency were observed on day 14 between patients with T1DM and those with T2DM. Decreases in renal glucose clearance were comparable regardless of the ipragliflozin dose in both groups of patients. The estimated mean Emax and AUC24h producing 50% of Emax (EX50) were 45.1 mL/min (95% CI, 37.0-53.2 mL/min) and 2160 ng·h/mL (95% CI, 929-3390 ng·h/mL), respectively, in all patients with T1DM and T2DM. Observed FPG in patients with T1DM was reproduced well by the simulation from the previously established FPG model. IMPLICATIONS: The PK/PD properties for ipragliflozin were comparable between patients with T1DM and T2DM, suggesting no substantial difference in PK/PD relationships in both patient populations. The dose regimen used for patients with T2DM was also recommended for a Phase III study in Japanese patients with T1DM. ClinicalTrials.gov identifiers: NCT01023945 and NCT02529449.

Pharmacokinetics, Pharmacodynamics, and Safety of Peficitinib (ASP015K) in Healthy Male Caucasian and Japanese Subjects.

BACKGROUND AND OBJECTIVE: Peficitinib pharmacokinetics and pharmacodynamics have been characterized mainly in Caucasian subjects. This study investigated the pharmacokinetics, pharmacodynamics, safety, and tolerability of peficitinib in healthy Japanese subjects compared with Caucasian subjects. METHODS: In this single-center, randomized, double-blind, placebo-controlled study, a cohort of healthy Japanese (n = 24) and Caucasian (n = 24) men received a single oral dose of peficitinib (20, 60, or 200 mg) or placebo. Another cohort of Japanese men (n = 24) received peficitinib (10, 30, or 100 mg) or placebo twice daily for 7 days. Pharmacokinetic and pharmacodynamic parameters were assessed, and adverse events (AEs) monitored throughout. RESULTS: Dose proportionality of maximum plasma drug concentration (Cmax) and area under the plasma concentration-time curve extrapolated to infinity (AUCinf) was demonstrated for both ethnicities. The geometric mean ratio for dose-normalized Cmax was 45.7-98.8% higher and AUCinf was 33.8-66.4% higher in Japanese versus Caucasian subjects. Mean peak inhibition of STAT5 phosphorylation was higher in Japanese than Caucasian subjects for a given peficitinib dose, but inhibition was comparable across ethnicities for a given plasma peficitinib concentration. In the multiple-dose study, plasma peficitinib concentrations were similar on day 1 and day 7. All AEs were mild, and none resulted in study discontinuation. CONCLUSIONS: Peficitinib was well tolerated at doses up to 200 mg daily for 7 days in healthy Japanese subjects. Dose-proportional exposure was demonstrated across the single-dose range of 20-200 mg, with greater peficitinib exposure in Japanese compared with Caucasian subjects. The pharmacokinetic/pharmacodynamic relationships were considered comparable between these populations. CLINICALTRIALS. GOV IDENTIFIER: NCT01225224.