Pharmacokinetics and safety of sirukumab following a single subcutaneous administration to healthy Japanese and Caucasian subjects.

OBJECTIVE: Sirukumab (CNTO 136) is a human mAb with high affinity and specificity for binding to interleukin-6. This Phase 1 study evaluated the pharmacokinetics, immunogenicity, safety, and tolerability of sirukumab following a single subcutaneous (s.c.) administration in healthy male Japanese and Caucasian subjects. METHODS: Japanese and Caucasian subjects were randomized to placebo or 25, 50, or 100 mg sirukumab. Blood samples were collected to measure serum sirukumab concentration and antibodies to sirukumab. Noncompartmental analysis and population pharmacokinetic modeling were conducted to characterize sirukumab pharmacokinetics. Adverse events were monitored at each visit. RESULTS: 25 Japanese and 24 Caucasian subjects received sirukumab and were included in the pharmacokinetic evaluation. Mean Cmax and AUC0-∞of sirukumab increased in an approximately dose-proportional manner in both Japanese and Caucasian subjects. Median tmax was 3 -5 days after s.c. administration of sirukumab. Mean t1/2 was 15 -16 days in Japanese and 15 -18 days in Caucasian subjects. A one-compartment population pharmacokinetic model adequately described sirukumab pharmacokinetics following s.c. administration. The estimated population means for CL/F, V/F, and Ka were 0.54 ±0.03 l/day, 12.2 ±0.55 l, and 0.77 ±0.07 day-1, respectively. Race was not a significant covariate on CL/F or V/F. No subject was positive for antibodies to sirukumab. Adverse events were generally mild and did not appear to be dose-related or lead to study discontinuation. CONCLUSIONS: Sirukumab pharmacokinetics following subcutaneous administration was linear at doses ranging 25 -100 mg and was comparable between Japanese and Caucasian subjects. A single subcutaneous administration of 25, 50, or 100 mg sirukumab appeared to be well tolerated by both Japanese and Caucasian healthy male subjects.

Cabozantinib in Japanese patients with advanced hepatocellular carcinoma: a phase 2 multicenter study.

BACKGROUND: To evaluate the efficacy and safety of cabozantinib in Japanese patients with advanced hepatocellular carcinoma (HCC) who had progressed following one or two lines of systemic therapy including sorafenib. An exploratory evaluation in sorafenib-naïve patients was performed. METHODS: In this open-label, single-arm, phase 2 trial, patients received oral cabozantinib 60 mg once daily. The primary endpoint was progression-free survival (PFS) rate at Week 24. Secondary endpoints included PFS, overall survival (OS), objective response rate (ORR, best response of complete/partial response), disease control rate (DCR, objective response or stable disease) and safety. RESULTS: Thirty-four patients received cabozantinib across 17 centers (prior sorafenib cohort, n = 20; sorafenib-naïve cohort, n = 14). PFS rate at 24 weeks was 59.8% [90% confidence interval (CI) 36.1-77.2%] in the prior sorafenib cohort, 16.7% (90% CI 4.0-36.8%) in the sorafenib-naïve cohort and 40.1% (90% CI 24.8-55.0%) overall. Median PFS was 7.4 months for the prior sorafenib cohort, 3.6 months for the sorafenib-naïve cohort, and 5.6 months overall. OS rate at 6 months was 100.0%, 78.6% and 91.1%, respectively; DCR was 85.0%, 64.3% and 76.5%, respectively. The ORR was 0.0% for both cohorts. All patients required dose modifications due to adverse events, the most common of these were palmar-plantar erythrodysesthesia syndrome and diarrhea. Three patients (8.8%) discontinued due to adverse events other than disease progression. CONCLUSIONS: Cabozantinib 60 mg/day has a favorable benefit/risk profile for Japanese patients with advanced HCC who have previously received one or two lines of systemic anticancer therapy including sorafenib. (Clinical trial registration: NCT03586973).

Efficacy and safety of trelagliptin in Japanese patients with type 2 diabetes with severe renal impairment or end-stage renal disease: Results from a randomized, phase 3 study.

INTRODUCTION: To investigate the efficacy and safety of trelagliptin 25 mg in patients with type 2 diabetes mellitus with severe renal impairment or end-stage renal disease. MATERIALS AND METHODS: This multicenter, randomized, phase 3 study comprised a 12-week double-blind phase followed by a 40-week open-label phase. Patients had type 2 diabetes mellitus with severe renal impairment (creatinine clearance <30 mL/min) or end-stage renal disease (undergoing hemodialysis), and were receiving diet and/or exercise therapy with/without one antidiabetic drug. RESULTS: Patients were randomized to trelagliptin (A/A, n = 55) or placebo (P/A, n = 52; double-blind phase). Both groups received trelagliptin in the open-label phase. The least square mean change (95% confidence interval [CI]) from baseline in hemoglobin A1c at the end of the double-blind phase was -0.71% (95% CI -0.885, -0.542) and 0.01% (95% CI -0.170, 0.183) in the A/A and P/A groups, respectively (intergroup least square means difference -0.72%, 95% CI -0.966, -0.473; P < 0.0001). Mean hemoglobin A1c decreased after trelagliptin treatment in the P/A group to similar levels observed in the A/A group and remained comparable in both groups versus baseline up to week 52. In the double-blind phase, the incidence of treatment-emergent adverse events (TEAEs) was 72.7% and 61.5% in the A/A and P/A group, respectively; most TEAEs were mild-to-moderate, except in one patient (P/A group), who experienced two severe TEAEs. The incidence of serious TEAEs was 7.3% and 3.8% in the A/A and P/A group, respectively. CONCLUSIONS: Once-weekly trelagliptin 25 mg was efficacious, with no major safety concerns, and represents a meaningful treatment option in this patient population.

Science-based Ethnic Bridging in Drug Development; Review of Recent Precedence and Suggested Steps Forward.

BACKGROUND: Exposure, safety and/or efficacy of drugs are subject to potential differences between human races or ethnicities, as acknowledged by regulatory guidance and by label texts of various, but not all approved drugs. OBJECTIVE: The objective of the present review was to assess recent regulatory precedence on drug use and race or ethnicity, with the goal of identifying opportunities for increasing the informative value of clinical ethnic or racial bridging in drug development. METHODS: Recently, (January 2014-July 2018) FDA approved drug product label texts and approval packages were reviewed for claims, comments and underlying data on use of the product in specific ethnic or racial groups. RESULTS: Among the 266 FDA-approved products, no product with unambiguous race- or ethnicity specific dosing instructions was retrieved. A small majority (55%) was approved with a claim or comment on race or ethnicity, and of these, a large majority (87%) was based on population pharmacokinetic data analysis. Statements were often related to incidence of a genotype for drug metabolizing enzyme or for other risk factors, or were related to body weight. Absence of clinically relevant exposure differences were often justified in terms of exposure ratios that notably exceeded the typical 0.80-1.25 no-effect boundary. CONCLUSIONS: Recent precedence reflected a pragmatic, descriptive approach of racial or ethnic bridging, apparently meeting current regulatory expectations, whilst not resulting in strict guidance to prescribers. We recommend further work on defining the objectives of bridging studies, as well as criteria for their design and data analysis. Regarding the latter, we recommend investigating the value of prospectively defined tests for similarity with appropriate follow-up analysis in the case where the test has failed.

Phase 1 study in Japan of siltuximab, an anti-IL-6 monoclonal antibody, in relapsed/refractory multiple myeloma.

Siltuximab, a chimeric monoclonal antibody with high affinity and specificity for interleukin-6, has been shown to enhance anti-multiple myeloma activity of bortezomib and corticosteroid in vitro. We evaluated the safety, pharmacokinetics, immunogenicity, and antitumor effect of siltuximab in combination with bortezomib and dexamethasone in Japanese patients with relapsed or refractory multiple myeloma. This open-label, phase 1, dose-escalating study used two doses of siltuximab: 5.5 and 11.0 mg/kg (administered on day 1 of each 21-day cycle). In total, nine patients were treated. The most common grade 3/4 adverse events, lymphopenia (89 %) and thrombocytopenia (44 %), occurred in patients receiving both doses of siltuximab; however, no dose-limiting toxicities (DLTs) were observed. Following intravenous administration of siltuximab at 5.5 and 11.0 mg/kg, the maximum serum concentration and the area under the curve from 0 to 21 days and from 0 to infinity increased in an approximately dose-proportional manner. Mean half-life, total systemic clearance, and volume of distribution were similar at doses of 5.5 and 11.0 mg/kg. Across both doses, six of the nine patients had complete or partial response (22 and 44 %, respectively). In conclusion, as no DLT was observed, the recommended dose for this combination is 11.0 mg/kg once every 3 weeks. The study is registered at http://www.clinicaltrials.gov as NCT01309412.

Functional characterization of single nucleotide polymorphisms with amino acid substitution in CYP1A2, CYP2A6, and CYP2B6 found in the Japanese population.

As a part of the studies conducted by the Pharma SNPs Consortium (PSC), the enzyme activities of CYP1A2, CYP2A6 and CYP2B6 variants with altered amino acids as a result of single nucleotide polymorphisms (SNPs) found among the Japanese population were analyzed under a unified protocol using the same lots of reagents by the laboratories participating in the PSC. Mutations in CYP1A2, CYP2A6 and CYP2B6 were introduced by site-directed mutagenesis and the wild type and mutated CYP molecules were expressed in Escherichia coli. The expressed cytochrome P450s were purified and the enzyme activities were measured in reconstitution systems. CYP1A2 and CYP1A2Gln478His did not show any differences in 7-ethoxyresorufin O-deethylase activity. CYP2A6 and CYP2A6Glu419Asp metabolized coumarin to form 7-hydroxycoumarin in a similar manner, whereas CYP2A6Ile471Thr showed low activity compared to the wild-type CYP2A6. CYP2B6, CYP2B6Pro167Ala and CYP2B6Arg487Cys showed the same activity for 7-ethoxy-4-triflouromethyl-coumarin O-deethylation. However, CYP2B6Gln172His was roughly twice as active as CYP2B6 and the other CYP2B6 variants for 7-ethoxy-4-triflouromethylcoumarin O-deethylation activity. Although higher inter- and intra-laboratory variations were observed for the calculated Km and V(max) values because the studies were conducted in several different laboratories, the degree of variations was reduced by the increased number of analyses and the adoption of a simple analysis system.

Tissue-specific regulation of expression and activity of P-glycoprotein in adjuvant arthritis rats.

Cyclosporine A and steroids are effective against rheumatoid arthritis and also known as substrates of P-glycoprotein (P-gp). We investigated the effect of arthritis on the hepatic and intestinal P-gp activity in rats, and substantiated the expression level of the hepatic P-gp. Doxorubicin was used as a P-gp substrate. Cumulative biliary excretion and intestinal exsorption of doxorubicin following intravenous administration were compared between adjuvant arthritis (AA) and normal rats. Intestinal P-gp activity was also investigated by intestinal everted sac method, and hepatic P-gp was detected by FITC-labeled antibody and visualized using a confocal laser microscope system. Biliary clearance of doxorubicin in AA rats was significantly decreased from that in normal rats. The expression level of the hepatic P-gp in AA rats was very low compared to normal rats, indicating down-regulation. Intestinal exsorption clearance was not different between AA and normal rats. Permeability of doxorubicin across intestinal everted sac was comparable between AA and normal rats, corresponding to in vivo study. In AA rats, hepatic P-gp activity was decreased due to the reduction of expression level, but intestinal P-gp activity was not changed. Different regulation systems may be involved in liver and intestine.

Lack of racial differences in the pharmacokinetics of subcutaneous golimumab in healthy Japanese and Caucasian male subjects.

This phase 1 study evaluated the single-dose pharmacokinetics and safety of subcutaneous golimumab, a human anti-tumor necrosis factor-alpha monoclonal antibody, in healthy Japanese and Caucasian subjects. Eligible subjects were males, aged 20 to 45 years, weighing 50 to 90 kg with a body mass index of 19 to 30 kg/m(2). Japanese and Caucasian subjects were matched by body weight and dose group. Blood samples were collected through day 50 following a single subcutaneous injection of golimumab 50 or 100 mg. The pharmacokinetic parameters were determined using a noncompartmental method. All 51 subjects (24 Japanese, 27 Caucasian) were included in the safety analysis; 47 completed the study and were included in the pharmacokinetic analysis. The pharmacokinetics of golimumab were comparable in both race groups. Peak concentrations were observed approximately 4 to 6 days after administration. No significant differences in exposure or mean half-life (range, 11-13 days) were observed between Japanese and Caucasian subjects at the same dose level. Regardless of race, serum golimumab exposure increased with increasing dose. Mean apparent clearance ranged from 12 to 19 mL/kg/d. Mean apparent volume of distribution (224-262 mL/kg) remained constant with an increase in dose. No antibodies to golimumab were detected. Single subcutaneous injections of golimumab 50 mg or 100 mg were generally well tolerated in these healthy male Japanese and Caucasian subjects.