Pharmacokinetics, Pharmacodynamics and Population Pharmacokinetic/Pharmacodynamic Modelling of Bilastine, a Second-Generation Antihistamine, in Healthy Japanese Subjects.

BACKGROUND AND OBJECTIVES: Bilastine is a novel second-generation antihistamine for the symptomatic treatment of allergic rhinitis and urticaria. The objective of this study was to evaluate the pharmacokinetics, pharmacodynamics, and tolerability of bilastine following single and multiple oral doses in healthy Japanese subjects. The pharmacokinetic and pharmacodynamic profiles were compared with those reported in Caucasian subjects. METHODS: In a single-blind, randomized, placebo-controlled, parallel-group, single- and multiple-ascending dose study, bilastine tablets were administered at single doses of 10, 20, and 50 mg (Part I), and once daily for 14 days at 20 and 50 mg (Part II). RESULTS: After single oral doses, maximum plasma concentrations (C max) were reached at 1.0-1.5 h postdose. Plasma exposure [C max and area under the plasma concentration-time curve (AUC)] increased dose-proportionally at single doses of 10-50 mg. In repeated-dose administration, no remarkable differences were observed between Day 1 and Day 14 for C max or AUC. For inhibitory effects on wheal and flare response, bilastine 20 and 50 mg showed significant inhibition from 1.5 h after administration as compared with placebo, and the significant effect persisted for 24 h after administration. The rates of adverse events (AEs) were comparable between bilastine and placebo in both Part I and Part II. In addition, no dose- or administration period-dependent tendency of increase in rate of AEs or worsening of severity was observed. CONCLUSION: Bilastine exhibits similar single- and multiple-dose pharmacokinetic and pharmacodynamic characteristics in healthy Japanese subjects compared with those observed in Caucasian subjects in previous studies.

Safety and pharmacokinetic study of nab-paclitaxel plus carboplatin in chemotherapy-naïve patients with advanced non-small cell lung cancer.

BACKGROUND: Nanoparticle albumin-bound paclitaxel (nab-paclitaxel) is a Cremophor EL-free formulation of paclitaxel newly designed to avoid solvent-related toxicities. We have evaluated the safety, tolerability, pharmacokinetics, and tumor response profile of weekly nab-paclitaxel (100 mg/m(2)) infusion together with administration of carboplatin at an area under the curve (AUC) of 6 every 3 weeks in Japanese patients with advanced non-small cell lung cancer (NSCLC). METHODS: Nab-paclitaxel (100 mg/m(2)) was administered without steroid or antihistamine premedication as a 30-min intravenous infusion once a week in combination with carboplatin at an AUC of 6 on day 1 of repeated 21-day cycles. The pharmacokinetics of both drugs were analyzed, and both adverse events and treatment response were monitored. RESULTS: Eighteen patients were enrolled in the study. The most frequent treatment-related toxicities of grade 3 or 4 were neutropenia (67%), leukopenia (50%), and anemia (22%). No severe hypersensitivity reactions were observed despite the lack of premedication, and no unexpected or new toxicities were detected. Pharmacokinetics analysis did not reveal any substantial drug-drug interactions. Seven partial responses were observed among the 18 evaluable patients, yielding a treatment response rate of 38.9%. CONCLUSIONS: The combination of nab-paclitaxel (100 mg/m(2)) administered weekly and carboplatin at an AUC of 6 every 3 weeks was well tolerated in Japanese patients with advanced NSCLC. This combination therapy also showed promising antitumor activity and was not associated with relevant pharmacokinetic interactions.

Safety, tolerability and pharmacokinetics of TAS-108, a novel anti-oestrogen, in healthy post-menopausal Japanese women: a phase I single oral dose study.

TAS-108 is a novel steroidal anti-oestrogen, expected to be useful for the treatment of breast cancer. The present study was conducted to investigate the safety, tolerability and pharmacokinetics of TAS-108 following the administration at a single oral dose of 40 mg to up to 120 mg in 12 post-menopausal women and the effect of food on the pharmacokinetics of the drug. All adverse events were mild and involved transient symptoms that resolved without therapeutic intervention. TAS-108 was readily absorbed and plasma levels of TAS-108 steadily declined, apparently in a multi-exponential manner. C(max) and AUC(0-12) were proportionally increased with increasing dose of TAS-108. The C(max) and AUC(0-t) of TAS-108 and its metabolite, deEt-TAS-108, were significantly increased to approximately 150% when TAS-108 was administered after a meal. Food did not affect the elimination half-life of TAS-108 or its metabolites. In this escalating dose-study of TAS-108, the drug was well tolerated by healthy post-menopausal Japanese women. The pharmacokinetics of TAS-108 indicated dose proportionality, and its bioavailability was significantly increased by food intake.

Distribution of (7alpha)-21-[4-[(diethylamino) methyl]-2-methoxyphenoxy]-7-methyl-19-norpregna-1,3,5(10)-trien-3-ol-20-[14C]2-hydroxy-1,2,3-propanetricarboxylate ([14C]TAS-108) and its metabolites after single oral administration to rats bearing 7,12-dimethylbenz(alpha)anthracene-induced mammary tumor.

(7Alpha)-21-[4-[(diethylamino)methyl]-2-methoxyphenoxy]-7-methyl-19-norpregna-1,3,5(10)-trien-3-ol 2-hydroxy-1,2,3-propanetricarboxylate (TAS-108) is a novel steroidal antiestrogen, modulating the differential recruitment of transcriptional cofactors by liganded estrogen receptors and representing a promising agent for the treatment of breast cancer. To understand better the relationships between the drug exposure and the efficacy or toxicity of TAS-108, we investigated the metabolism and distribution of TAS-108 after oral administration of [14C]TAS-108 to rats bearing a 7,12-dimethylbenz(alpha)anthracene-induced mammary carcinoma. The metabolites (7alpha)-21-[4-[(ethylamino)methyl]-2-methoxyphenoxy]-7-methyl-19-norpregna-1,3,5(10)-trien-3-ol (deEt-TAS-108), (7alpha)-21-[4-[(diethylamino)methyl]-2-methoxyphenoxy]-7-methyl-19-norpregna-1,3,5(10)-trien-3-ol-N-oxide (TAS-108-N-oxide), and 3-methoxy-4-[(7alpha)-7-methyl-19-norpregna-1,3,5(10)-trien-3-ol-21-yl]oxybenzoic acid (TAS-108-COOH) were identified as the major metabolites in the plasma, and in addition, (7alpha)-21-[4-[(ethylamino)methyl]-2-methoxyphenoxy]-3-methoxy-7-methyl-19-norpregna-1,3,5(10)-triene (O-Me-deEt-TAS-108) was identified as a novel metabolite in this study. The time-concentration profiles of TAS-108 and its metabolites in the plasma were compared with those in the tumor and uterus of the rats. Radioactivity was found at a high level in various organs including lung, liver, spleen, ovary, and many glands at 12 h and was relatively higher in tumor tissue than in plasma. On the other hand, the levels of radioactivity in the brain and eyeball were very low or not detectable. TAS-108, deEt-TAS-108, and O-Me-deEt-TAS-108 were extensively distributed in the rat tissues and the tumor, with corresponding tissue/plasma ratios for Cmax and area under the curve in the range of 7 to 100. In contrast, TAS-108-COOH and TAS-108-N-oxide were hardly distributed to the tissues and thus may not contribute to the efficacy or toxicity of TAS-108. Thus, TAS-108, deEt-TAS-108, and O-Me-deEt-TAS-108, being distributed highly in tumor tissue, may be more important for the efficacy and toxicity of TAS-108 in vivo than TAS-108-COOH and TAS-108-N-oxide.