A double-blind, randomized phase II study of dicycloplatin plus paclitaxel versus carboplatin plus paclitaxel as first-line therapy for patients with advanced non-small-cell lung cancers.

INTRODUCTION: The aim of this study was to compare the efficacy and toxicity of dicycloplatin plus paclitaxel with those of carboplatin plus paclitaxel as first-line treatment for patients with advanced non-small-cell lung cancer (NSCLC). MATERIAL AND METHODS: In this study, 240 NSCLC patients with stage IIIB (with pleural effusion) and stage IV disease were randomly assigned (1: 1) to receive dicycloplatin 450 mg/m(2) or carboplatin AUC = 5, in combination with paclitaxel 175 mg/m(2) (D + P or C + P) every 3 weeks for up to 4 to 6 cycles. The primary endpoint was response rate. Secondary endpoints included progression-free survival (PFS), overall survival (OS) and adverse events. RESULTS: The response rates for the D + P and C + P arm were 36.44% and 30.51%, respectively (p = 0.33). The median PFS was 5.6 months in the D + P arm and 4.7 months in the C + P arm (p = 0.31). The median OS was 14.9 months for D + P and 12.9 months for C + P (p = 0.37). Adverse events in the two arms were well balanced. The most common grade 3/4 adverse event was hematologic toxicity. CONCLUSIONS: Patients treated with D + P had similar response and survival rates to those treated with C + P, and toxicities of both treatments were generally tolerable.

Pharmacokinetics, pharmacodynamics, safety, and tolerability of hyzetimibe (HS-25) in healthy Chinese subjects.

Hyzetimibe (HS-25) is a new cholesterol absorption inhibitor. We performed the first-in-human study to assess the safety, tolerability, and pharmacokinetics (including the effect of food) and pharmacodynamics (effect on blood lipid level) following single (1, 3, 5, 10, 20, and 30 mg) and multiple (5, 10, and 20 mg) ascending-dose of hyzetimibe in healthy subjects. An increase of exposure (area under the plasma concentration-time curve and maximum plasma concentration) to hyzetimibe and hyzetimibe-glucuronide (HS-25M1) was observed in an approximately dose-proportional manner. A terminal half-life of approximately 21 hours was observed with doses ranging between 5 and 30 mg. Steady state was achieved by day 8 of once-daily dosing with 1.6- and 1.2-fold accumulation for hyzetimibe and hyzetimibe-glucuronide, respectively. Food did not have any effect on hyzetimibe and hyzetimibe-glucuronide exposure. Administration of hyzetimibe once daily for 10 days reduced the levels of low-density lipoprotein cholesterol levels in healthy subjects and these recovered after discontinuation of this drug. All of the adverse events were mild or moderate in severity, and the majority of them were unrelated to hyzetimibe, with no dose-dependent trends. These findings suggest that hyzetimibe could be a potential treatment for hypercholesterolemia.

Quantitative structure-activity relationship and quantitative structure-pharmacokinetics relationship of 1,4-dihydropyridines and pyridines as multidrug resistance modulators.

PURPOSE: The aim of this study was to develop quantitative structure-activity/pharmacokinetic relationships (QSAR/QSPKR) for a series of synthesized 1,4-dihydropyridines (DHPs) and pyridines as P-glycoprotein (P-gp) inhibitors. METHODS: Molecular descriptors of test compounds were generated by 3D molecular modeling using SYBYL and KowWin programs. Forward inclusion coupled with multiple linear regression (MLR) was used to derive a QSAR equation for Ca2+ channel binding. A multivariate statistical technique, partial least square (PLS) regression, was applied to derive a QSAR model for P-gp inhibition and QSPKR models. Cross-validation using the "leave-one-out" method was performed to evaluate the predictive performance of models. RESULTS: For Ca2+ channel binding, the MLR equation indicated a good correlation between observed and predicted values (R2 = 0.90), and cross-validation confirmed the predictive ability of the model (Q2 = 0.67). For P-gp reversal, the model obtained by PLS could account for most of the variation in P-gp inhibition (R2 = 0.76) with fair predictive performance (Q2 = 0.62). Nine structurally related 1,4-DHP drugs were used for QSPKR analysis. The models could explain the majority of the variation in clearance (R2 = 0.90), and cross-validation confirmed the prediction ability (Q2 = 0.69). CONCLUSION: QSAR/QSPKR models were developed, and the QSAR models were capable of identifying synthesized 1,4-DHPs and pyridines with potent P-gp inhibition and reduced Ca2+ channel binding. The QSPKR models provide insight into the contribution of electronic, steric, and lipophilic factors to the clearance of DHPs.

Liquid chromatography/tandem mass spectrometry for the determination of fluoxetine and its main active metabolite norfluoxetine in human plasma with deuterated fluoxetine as internal standard.

Fluoxetine (F) and its N-demehylated metabolite norfluoxetine (NF) are selective inhibitors of serotonin reuptake in humans. A new sensitive rapid method for the simultaneous determination of F and NF in plasma was established and validated, and was further applied to assess the bioequivalence of two oral formulations of F in 22 healthy Chinese male volunteers who received a single oral dose of each formulation (containing 20 mg of fluoxetine hydrochloride). The new method involves using liquid chromatography/tandem mass spectrometry (LC/MS/MS) in multiple reaction monitoring mode with deuterated fluoxetine (DF) as internal standard. High levels of analytical sensitivity and specificity of MS/MS detection enabled use of a simple liquid-liquid extraction procedure. The combination of a simple sample clean-up procedure and short chromatographic run-time (5 min) considerably increased the productivity of the analytical method. The method was validated for the plasma concentration range 0.27-22 ng/mL for both of the test compounds, and the calibration curves were linear with coefficients of correlation >0.999. The limit of detection was 0.1 ng/mL for plasma F and NF. Taking the plasma sample size (200 micro L) into account the new method for determination of F and NF is more sensitive than those described previously.