Population pharmacokinetics of duloxetine in Japanese pediatric patients with major depressive disorder.

The objectives of this analysis were to characterize the pharmacokinetics of duloxetine in Japanese pediatric patients aged 9-17 years with major depressive disorder (MDD) and to explore potential intrinsic factors affecting its pharmacokinetics. A population pharmacokinetic (PK) model was developed with plasma steady-state duloxetine concentrations from Japanese pediatric patients with MDD in an open-label long-term extension trial in Japan (ClinicalTrials.gov Identifier: NCT03395353). Duloxetine pharmacokinetics in Japanese pediatric patients was well described by a one-compartment model with first-order absorption. The population mean estimates of CL/F and V/F of duloxetine were 81.4 L/h and 1170 L, respectively. Patient intrinsic factors were assessed for their potential influence on duloxetine apparent clearance (CL/F). Only sex was identified as a statistically significant covariate of duloxetine CL/F. Duloxetine pharmacokinetic parameters and model-predicted duloxetine concentrations at steady state in the Japanese pediatric population were compared with those in Japanese adults. The mean duloxetine CL/F in pediatrics is slightly higher than adults, it is, however, expected that comparable steady-state duloxetine exposure in pediatric patients can be achieved with the approved dose regimen for adults. The population PK model provides useful information to understand the pharmacokinetic characteristics of duloxetine for Japanese pediatric patients with MDD. CLINICALTRIALS.GOV IDENTIFIER: NCT03395353.

A non-randomized, open-label, single-arm, Phase 2 study of emibetuzumab in Asian patients with MET diagnostic positive, advanced gastric cancer.

PURPOSE: Mesenchymal-epithelial transition factor (MET) is expressed in gastric cancer and associated with poor clinical outcomes. We assessed activity, safety, and pharmacokinetics of emibetuzumab, a bivalent monoclonal anti-MET antibody that blocks ligand-dependent and ligand-independent MET signaling. METHODS: This non-randomized, single-arm, Phase 2 study enrolled Asian patients with MET diagnostic positive advanced gastric adenocarcinoma. Emibetuzumab (2000 mg, intravenous) was given on days 1 and 15 (28-day cycle). The primary endpoint was 8-week progression-free survival rate. Secondary objectives included safety, pharmacokinetics, overall survival, and change in tumor size. RESULTS: Tumors from 65 patients were immunohistochemically screened to enroll 15 MET diagnostic positive patients (23% positivity; 8 Japanese, 7 Korean; 10 male). Eight-week progression-free survival rate was 0.47 (70% CI, 0.33-0.59). Disease control rate was 40% (target lesion decreases, three patients; no complete/partial responses according to RECIST). Median overall survival was 17.1 weeks (95% CI, 6.3-not achievable). No serious emibetuzumab-related adverse events or new safety signals emerged. Grade ≥ 3 possibly drug-related adverse events were hyperkalemia, hyponatremia, and hyperuricemia (one each). Emibetuzumab's pharmacokinetics profile was similar to that observed previously. MET expression and clinical outcomes were not obviously associated. CONCLUSION: Emibetuzumab was well tolerated with limited single-agent activity in advanced gastric adenocarcinoma.

A phase I dose-escalation study of LY2875358, a bivalent MET antibody, given as monotherapy or in combination with erlotinib or gefitinib in Japanese patients with advanced malignancies.

Background MET is a tyrosine kinase receptor involved in the regulation of cell proliferation and migration. Reported here are the phase I dose-escalation results for LY2875358, a monoclonal antibody against MET, in Japanese patients with advanced malignancies. Methods The study comprised a 3 + 3 dose-escalation part for LY2875358 monotherapy in patients with advanced malignancies (Part A) followed by an assessment of LY2875358 in combination with erlotinib or gefitinib in patients with non-small cell lung cancer (Part B). LY2875358 was administered once every 2 weeks. The primary objective was to evaluate the safety and tolerability of LY2875358; secondary objectives included evaluation of pharmacokinetics, pharmacodynamics, and antitumor activity. Results Eleven patients received LY2875358 monotherapy at 3 dose levels (700 mg, N = 3; 1400 mg, N = 3; 2000 mg, N = 5) and 6 patients received LY2875358 2000 mg in combination with erlotinib (N = 3) or gefitinib (N = 3). No dose-limiting toxicities or serious adverse events related to LY2875358 were observed. The most frequently reported drug-related adverse events were hypoalbuminemia (2 patients) in Part A and dermatitis acneiform (4 patients) in Part B. LY2875358 area under the curve (AUC) and maximum concentration (Cmax) increased with dose over the dose range of 700 mg to 2000 mg. A best response of stable disease was achieved by 2/11 patients in Part A and 4/6 patients in Part B (disease control rate: 35 %). Conclusions LY2875358 at doses up to 2000 mg demonstrated a favorable safety and tolerability profile as monotherapy or in combination with erlotinib or gefitinib in Japanese patients with advanced malignancies.

Dose-escalation study of tabalumab with bortezomib and dexamethasone in Japanese patients with multiple myeloma.

B-cell activating factor (BAFF) promotes the survival and adhesion of multiple myeloma (MM) cells. Tabalumab (LY2127399) is an anti-BAFF monoclonal antibody. This phase 1, multicenter, open-label, nonrandomized, dose-escalation study evaluated the safety, tolerability, pharmacokinetics, pharmacodynamics and efficacy of tabalumab in combination with bortezomib and dexamethasone in Japanese patients with relapsed or refractory MM (RRMM). Sixteen patients received intravenous i.v. tabalumab 100 mg (Cohort 1, n = 4) or i.v. tabalumab 300 mg (Cohort 2, n = 12) in combination with oral dexamethasone 20 mg/day and i.v. or s.c. bortezomib 1.3 mg/m(2) . All patients had treatment-emergent adverse events (TEAE) possibly related to study treatment; the most common TEAE were thrombocytopenia (81.3%), lymphopenia (43.8%) and increased alanine aminotransferase (43.8%). Two (20.0%) dose-limiting toxicities were observed, both in Cohort 2 (tabalumab 300 mg), which was below the predefined cutoff for tolerability (<33%). The pharmacokinetics of tabalumab were similar when bortezomib was coadministered i.v. versus s.c. The overall response rate was 56.3%, suggesting that the combined treatment was effective. In conclusion, combined treatment with these three agents was well tolerated in this population of Japanese patients with RRMM. The study was registered at www.clinicaltrials.gov (NCT01556438).

Phase I study of LY2603618, a CHK1 inhibitor, in combination with gemcitabine in Japanese patients with solid tumors.

This phase I trial evaluated LY2603618, a selective inhibitor of the DNA damage checkpoint kinase 1, in combination with gemcitabine. Japanese patients with advanced solid tumors were enrolled. All patients received gemcitabine (1000 mg/m on days 1, 8, and 15 every 28 days) and either 170 mg (cohort 1) or 230 mg (cohort 2) of LY2603618. The primary objective was assessment of safety/tolerability. Pharmacokinetic/pharmacodynamic marker profiles were secondary objectives. Of the 17 patients enrolled, dose-limiting toxicities were observed in one patient in cohort 1 (n=7) and in two patients in cohort 2 (n=10). The most common grade 3 or more drug-related treatment-emergent adverse events were hematological. Three patients discontinued because of adverse events. Dose-dependent decreases in LY2603618 exposure were observed, but the LY2603618 pharmacokinetics at each dose were consistent within and between cycles and did not influence gemcitabine pharmacokinetics. Circulating plasma DNA decreased from baseline in all four patients who achieved a partial response. Administration of 170 or 230 mg of LY2603618 following a standard dose of gemcitabine showed acceptable safety and tolerability in Japanese patients with solid tumors.

Phase I study of oral gemcitabine prodrug (LY2334737) in Japanese patients with advanced solid tumors.

PURPOSE: LY2334737 is an oral gemcitabine prodrug. This Phase I study assessed the safety and tolerability of LY2334737 in Japanese patients with solid tumors and evaluated pharmacokinetics (PK), pharmacodynamics, and antitumor activity. METHODS: Patients with advanced/metastatic solid tumors received escalating doses of LY2334737 once daily for 14 days, followed by a 7-day drug-free period. Cycles were repeated until discontinuation criteria were met. RESULTS: Of 13 patients treated, 3 received 20 mg/day, 6 received 30 mg/day, 4 received 40 mg/day. On the 40 mg dose, 3 patients experienced dose-limiting toxicities (DLTs): hepatic toxicities (e.g., Grade [G]3/4 transaminase and G1-3 bilirubin elevation) and G4 thrombocytopenia; all 3 showed features of disseminated intravascular coagulation. One additional DLT occurred on the 30 mg dose (G3 transaminase elevation). Exploratory pharmacogenetic analyses identified a genetic variation in the CES2 gene potentially associated with these DLTs. PK data showed no clear relationship between the AUC of gemcitabine and its incorporation into leukocyte DNA; 2 of the 3 DLT patients had high incorporation. Two patients (30 mg/day) achieved stable disease with progression-free survival lasting 135 and 155 days. CONCLUSIONS: LY2334737 was tolerated by Japanese patients up to 30 mg/day. The toxicities observed at the 40 mg dose may require the development of alternative dosing schedules.

Effects of teriparatide in Japanese and non-Japanese populations: bridging findings on pharmacokinetics and efficacy.

Teriparatide is an anabolic therapy for osteoporosis approved in the United States since 2002 and European Union since 2003; however, approval in Japan lagged significantly. This report describes analyses based on International Conference on Harmonisation (ICH) E-5 guidelines that support bridging between Japanese studies and the large Fracture Prevention Trial (FPT). We analyzed data from single teriparatide doses in healthy Japanese and Caucasian postmenopausal women (J-PK) and from studies of 6 months [Phase 2, dose ranging (J-Ph2)] and 12 months [Phase 3, efficacy and safety (J-Ph3)] of randomized, placebo-controlled, once-daily treatment in Japanese subjects with osteoporosis. In J-PK, apparent teriparatide area-under-the-curve (AUC) and peak concentration (C (max)) were up to 40% higher in Japanese versus Caucasian women; however, body weight-adjusted values were comparable between populations; these findings were supported by population pharmacokinetic analyses. Between the FPT and Japanese studies, baseline demographic characteristics were similar but bone mineral density (BMD) at lumbar spine (L1-L4) and body weight were lower for Japanese subjects. With teriparatide 20 µg/day, significant increases in BMD were observed compared to placebo at 12 months in both the FPT and J-Ph3 study, and percent change and actual change in BMD were comparable between studies. Dose response at 6 months was also comparable across populations. No novel safety signals were identified in Japanese subjects. These analyses show that teriparatide clinical data met ICH E-5 criteria for bridging. Findings from foreign trials such as the FPT can thus be extrapolated to Japanese subjects treated with teriparatide 20 µg/day.

Comparison of pharmacokinetics, pharmacodynamics, safety, and tolerability of the amyloid ß monoclonal antibody solanezumab in Japanese and white patients with mild to moderate alzheimer disease.

OBJECTIVES: Solanezumab is a humanized anti-amyloid ß monoclonal antibody being developed as a passive immunization treatment to slow the progression of Alzheimer disease (AD). Pharmacokinetics (PK), pharmacodynamics, safety, and tolerability after a single dose of solanezumab were compared between Japanese and white patients with AD. METHODS: Japanese and white patients with mild to moderate AD were enrolled in 2 separate studies. In each study, single doses of solanezumab at 0.5, 1.5, 4.0, and 10.0 mg/kg were administered by intravenous infusion. Plasma concentrations of solanezumab and amyloid ß (Aß) were measured. A safety assessment was conducted up to 112 days after a single-dose administration of solanezumab. RESULTS: The PK profile was similar between the Japanese and the white patients with AD. In both the Japanese and the white patients, clearance and volume of distribution appeared similar across doses, suggesting that solanezumab exhibited dose-proportional PK within the studied dose range. A marked increase in plasma total Aß was observed; both the magnitude and time to reach maximum concentration tended to increase with increasing doses of solanezumab. Administration of solanezumab was generally well-tolerated in both Japanese and white patients with AD. CONCLUSIONS: When administered as a per-kilogram single dose of solanezumab, PK and pharmacodynamics (plasma total Aß1-40 concentration) in the Japanese patients with AD were comparable with those in the white patients with AD. In addition, solanezumab was generally well tolerated in both Japanese and white patients at all dose levels.

Pharmacokinetics, pharmacodynamics, tolerability, and safety of exenatide in Japanese patients with type 2 diabetes mellitus.

In this single-blind, parallel, placebo-controlled study, the pharmacokinetics, pharmacodynamics, tolerability, and safety of subcutaneous exenatide were evaluated in 40 Japanese patients with type 2 diabetes. Patients were allocated to 4 groups and randomized to receive exenatide (n = 8/group) or placebo (n = 2/group), with all receiving placebo on day 1. On day 2, patients received single-dose exenatide (2.5 microg [group A] or 5 microg [groups B, C, and D]) or placebo and then bid on days 3 to 5. On days 6 to 10, groups A and B continued on 2.5 and 5 microg bid; groups C and D received 10 and 15 microg bid, respectively. The last dose was given on the morning of day 10. All adverse events were mild or moderate in severity. Exenatide was generally well tolerated up to 10 microg. Exenatide was well absorbed with a median t(max) of 1.5 hours and mean t((1/2)) of 1.6 hours; exposure increased with dose. Up to 10 microg, exenatide reduced postprandial glucose concentrations in a dose-dependent fashion compared with placebo; decreases were similar for 10 and 15 microg. An E(max) model demonstrated that doses higher than 2.5 microg were necessary for adequate glycemic response. Based on tolerability and pharmacokinetic/pharmacodynamic relationships, 5 and 10 microg exenatide may be considered for further clinical development in Japanese patients with type 2 diabetes.

[Combined determination of urine uracil levels and plasma 5-FU clearance for a simple order-made treatment with anticancer agents of FU derivative].

Individual differences exist in the pharmacodynamics of fluorouracil-derived anticancer agents, with circadian variability even in the same patient probably due to individual differences in the distribution of dihydrophrimidine dehydrogenase (DPD), a decomposing enzyme. Though DPD activity is usually determined in the liver or blood, a more simplified estimation of DPD activity has been recently attempted using urine uracil levels. However, because urine uracil level has the drawback of being easily affected by food ingestion or kidney function, in this study it was determined simultaneously with the determination of plasma 5-FU clearance after sustained instillation of 250 mg 5-FU, in order to estimate DPD activity more accurately. A correlation was observed between urine uracil levels and 5-FU clearance. In cases showing a baseline urine uracil level below 25.1 mumol/g. Creatinine, the blood concentration decreased due to large 5-FU clearance, with a tendency for diminished efficacy of FU-derived anticancer agents. In cases showing a baseline urine uracil level above 99.9 mumol/g. Creatinine, on the other hand, adverse reactions due to FU anticancer agents tended to become more serious. Since urine uracil level can be determined easily, it could be the first choice in screening to detect abnormal metabolism of fluorouracil-derived anticancer agents under present circumstances. By combining determination of urine uracil level with 5-FU clearance, it seems possible to predict adverse effects and the effective rate of these agents more accurately. Under existing circumstances, where genetic analysis remains unavailable as a general practice, the combined determination of urine uracil levels and plasma 5-FU clearance may be beneficial in developing order-made treatments in cancer chemotherapy.