First-in-Human, Single-Ascending Dose and Food Effect Studies to Assess the Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of Cetagliptin, a Dipeptidyl Peptidase-4 Inhibitor for the Treatment of Type 2 Diabetes Mellitus.

BACKGROUND AND OBJECTIVES: Cetagliptin is a highly selective dipeptidyl peptidase-4 inhibitor under development to treat type 2 diabetes mellitus. This first-in-human study was conducted to characterise the pharmacokinetics, pharmacodynamics and tolerability of single-ascending oral doses of cetagliptin in healthy subjects. In addition, the effect of food on pharmacokinetics was evaluated. METHODS: Study 1 enrolled 66 healthy subjects in a double-blind, randomised, placebo-controlled, single-dose escalation study; sitagliptin was employed as a positive open-label control. Forty-four subjects were assigned to seven cohorts (cetagliptin 12.5, 25, 50, 100, 200, 300 or 400 mg); 12 subjects were assigned to the placebo group. The remaining ten subjects received sitagliptin 100 mg as the positive control. Blood, urine and faeces were collected for the pharmacokinetic analysis and determination of plasma dipeptidyl peptidase-4 inhibition, active glucagon-like peptide-1, glucose and insulin levels. In Study 2, 14 healthy subjects were assigned to a randomised, open-label, two-period crossover study, and received a single oral dose of cetagliptin 100 mg in the fasted state or after a high-fat meal, with a 14-day washout period between treatments. Blood samples were collected to evaluate the effects of food on the pharmacokinetics of cetagliptin. RESULTS: Following administration of a single oral dose, cetagliptin was rapidly absorbed, presenting a median time to maximum concentration of 1.0-3.25 h. The terminal half-life ranged between 25.8 and 41.3 h, which was considerably longer than that of sitagliptin. The area under the plasma concentration-time curve was approximately dose proportional between 25 mg and 400 mg, and the increase in maximum concentration was greater than dose proportional. The unchanged drug was mainly excreted in the urine (27.2-46.2% of dose) and minimally via the faeces (1.4% of dose). Dipeptidyl peptidase-4 inhibition, an increase in active glucagon-like peptide-1 and a slight decrease in blood glucose were observed, whereas insulin was not significantly altered when compared with placebo. The weighted average dipeptidyl peptidase-4 inhibition by cetagliptin 100 mg was higher than that mediated by sitagliptin 100 mg. Cetagliptin was well tolerated up to a single oral dose of 400 mg. No food effects were noted. CONCLUSIONS: Cetagliptin inhibited plasma dipeptidyl peptidase-4 activity, increased levels of active glucagon-like peptide-1 and was well tolerated at single doses up to 400 mg, eliciting no dose-limiting toxicity in healthy volunteers. Food did not affect the pharmacokinetics of cetagliptin. CLINICAL TRIAL REGISTRATION: The studies were registered at http://www.chinadrugtrials.org.cn (Nos. CTR20180167 and CTR20181331).

Association analysis of SNPs present in plasma with adverse events and population pharmacokinetics in Chinese sunitinib treated patients with renal cell carcinoma.

BACKGROUND: Sunitinib is a tyrosine kinase inhibitor with effective therapeutic outcomes in patients with renal-cell carcinoma. The study were to analyze the association of single-nucleotide polymorphisms present in cell-free DNA and pharmacokinetics with sunitinib treatment-emergent adverse events in Chinese patients with renal-cell carcinoma. MATERIALS AND METHODS: We genotyped 8 keys SNPs in 6 candidate genes. The plasma concentrations of sunitinib and N-desethyl sunitinib were measured using a high performance liquid chromatography-tandam mass spectrometry method. Correlations between the single-nucleotide polymorphisms and adverse events were investigated by univariate and multivariate logistic regression and we quantitatively evaluated the effect of single-nucleotide polymorphisms on the pharmacokinetics of sunitinib by using a population PK model. RESULTS: Necessary dose reductions of sunitinib were significantly correlated with SNP rs1933437 in FLT3. A higher severity of AEs were collected with SNP rs2032582 in ABCB1 and rs1800812 in PDGFRα. Thrombocytopenia was collected with rs1800812 in PDGFRα. Our study provides a population PK model of sunitinib with the ABCB1 genotype as a predictive covariate for apparent oral clearance. CONCLUSIONS: Our study preliminarily confirmed the hypothesis that the pharmacokinetics of sunitinib is affected by the SNPs of enzyme in Chinese renal-cell carcinoma patients, and this affects the different distribution and severity of adverse events of sunitinib.

Pharmacokinetics of oxycodone hydrochloride and three of its metabolites after intravenous administration in Chinese patients with pain.

OBJECTIVES: The aim of this study is to evaluate the pharmacokinetic profile of oxycodone and three of its metabolites, noroxycodone, oxymorphone and noroxymorphone after intravenous administration in Chinese patients with pain. METHODS: Forty-two subjects were assigned to receive intravenous administration of oxycodone hydrochloride of 2.5, 5 or 10 mg. Plasma and urine samples were collected for up to 24 h after intravenous administration of oxycodone hydrochloride. RESULTS: Pharmacokinetic parameters showed that mean values of C(max), AUC(0-t) and AUC(0-∞) of oxycodone were dose dependent, whereas Tmax and t(1/2) were not. The mean AUC(0-t) ratio of noroxycodone to oxycodone ranged from 0.35 to 0.42 over three doses, and those of noroxymorphone, or oxymorphone, to oxycodone were ranging of 0.06-0.08 and 0.007-0.008, respectively. Oxycodone and its three metabolites were excreted from urine. Approximately 10% of unchanged oxycodone was recovered in 24 h. Most adverse events (AEs) reported were mild to moderate. The frequently occurred AEs were dizziness, nausea, vomiting, drowsiness and fatigue. No dose-related AEs were found. CONCLUSION: Our pharmacokinetics of oxycodone injection in Chinese patients with pain strongly support continued development of oxycodone as an effective analgesic drug in China.

Development and validation of a HPLC-MS/MS method with electrospray ionization for quantitation of potassium oxonate in human plasma: Application to a pharmacokinetic study.

A rapid, sensitive and specific HPLC-MS/MS method was developed and validated for the quantification of potassium oxonate (Oxo) in human plasma using [(13)C(2),(15)N(3)]-Oxo as an internal standard (IS). The target substance was separated from human plasma using the solid-phase extraction method. Chromatography separation was performed on a Waters:Atlantis dC(18) column (150×4.6 mm, 5.0 µm) with a mobile phase consisting of H(2)O with 0.1% formic acid in acetonitrile (90:10, v/v). The mass spectrometer works with electrospray ionization and multiple reaction monitoring in its negative ion mode, using target ions at [M-H](-) m/z 111.9 for Oxo and [M-H](-) m/z 117.0 for the IS. The mean standard curve was linear (r=0.9991) over the concentration range of 2.0-200.0 ng/ml and had good back-calculated accuracy and precision. The intra- and inter-day precision were <6.33% and the accuracy was >99.38%. The extraction recovery was >60.26%. The lower limit of quantification achieved with this method was 2.0 ng/ml. This assay method was demonstrated to be accurate, sensitive and simple and was successfully applied to a pharmacokinetic study following single oral administration of a 40-mg S-1 capsule in 12 tumor patients.

Pharmacokinetics and safety of a new bioengineered thrombolytic agent, human tissue urokinase type plasminogen activator in Chinese healthy volunteers.

The aim of our study was to investigate the pharmacokinetics and safety of human tissue urokinase type plasminogen activator (HTUPA) in healthy Chinese subjects after intravenous administration. Thirty-two subjects were given intravenous injection doses of 5-35 mg of HTUPA for safety evaluation. Twenty-four subjects were given 10, 20 or 30 mg HTUPA for pharmacokinetic assessment. Safety and tolerance were evaluated by monitoring adverse events, laboratory parameters, electrocardiography and vital signs. HTUPA concentration in human serum samples was determined by an enzyme-linked immunosorbent assay (ELISA) method. The main pharmacokinetic parameters were calculated by DAS software. HTUPA was generally well tolerated and in the whole study course no serious adverse events occurred. The main pharmacokinetic parameters were as follows: geometric mean [95% confidence interval, CI] for t1/2 were 1.5 (1.4, 1.6), 1.3 (1.2, 1.4), and 1.2 (1.2, 1.3) h, AUC0-t were 1.0 (0.7, 1.3), 2.1 (1.5, 2.7), and 5.6 (4.7, 6.6) mg h L(-1), AUC0-∞ were 1.1 (0.8, 1.3), 2.1 (1.5, 2.7), and 5.8 (4.7, 6.7) mg h L(-1) for 10, 20, and 30 mg group, respectively. The main pharmacokinetic parameters were not significantly different between males and females (P>0.05). No serious adverse events were reported by the subjects or revealed by clinical or laboratory examinations, suggesting the given doses were safe and well tolerated.

Simple, sensitive and rapid HPLC-MS/MS method for the determination of cepharanthine in human plasma.

A rapid, sensitive and specific method for the determination of cepharanthine in human plasma using high performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) was described. Cepharanthine and the internal standard (I.S.), telmisartan, were extracted from human plasma by methanol to precipitate the protein. A centrifuged upper layer was then evaporated and reconstituted with 100µL methanol. Chromatographic separation was performed on an AGILENT XDB-C(8) column (150mm×2.1mm, 5.0µm, Agilent, USA) using a gradient mobile phase with 1mmol/L ammonium acetate in water with 0.05% formic acid and methanol. Detection and quantitation was performed by MS/MS using electrospray ionization (ESI) and multiple reaction monitoring (MRM) in the positive ion mode. The most intense [M+H](+) MRM transition of cepharanthine at m/z 607.3→365.3 was used for quantitation and the transition at m/z 515.5→276.4 was used to monitor telmisartan. The calibration curve was linear within the concentration range of 0.5-200.0ng/mL (r=0.9994). The limit of quantification (LOQ) was 0.5ng/mL. The extraction recovery was above 81.1%. The accuracy was higher than 92.3%. The intra- and inter-day precisions were less than 9.66%. The method was accurate, sensitive and simple and was successfully applied to a pharmacokinetic study after single intravenous administration of 50mg cepharanthine in 12 healthy Chinese volunteers.