Pharmacokinetic and pharmacodynamic evaluation study of etomidate: a randomized, open-label, 2-period crossover study in healthy Chinese subjects.

Etomidate is a sedative and hypnotic drug through intravenous administration that act on the central nervous system through GABA (Gamma-Amino Butyric Acid) receptors, which is widely used in anesthesia induction and maintenance and long-term sedation in severe patients. The study aimed to evaluate the pharmacokinetic and pharmacodynamic properties of two etomidate fat emulsions after administration through the intravenous infusion pump in healthy Chinese subjects. A randomized, open-label, 2-period crossover study was performed in 52 healthy subjects. The wash-out period was 7 days. Blood samples and pharmacodynamic index values were collected at the specified time points. Etomidate concentrations were measured using validated liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters were analyzed using a non-compartment model method. Pharmacodynamic parameters were calculated using pharmacodynamic index values. The study also evaluated the safety of the etomidate. Both the pharmacokinetic parameters and pharmacodynamic parameters result of the test and reference formulation were very similar. The 90% confidence intervals (CI) of the geometric least-squares mean (GLSM) ratios of the test to reference formulation were 91.33-104.96% for the maximum plasma concentration (Cmax), 97.21-102.03% for the area under the plasma concentration time curve from time 0 to the time of the last measurable concentration (AUC0-t), and 97.22-102.33% for the area under the plasma concentration time curve from time 0 to infinity (AUC0-∞). Meanwhile, the 90% CI of the GLSM ratios of the test to reference formulation were 102.28-110.69% for the minimal BIS value (BISmin), 99.23-101.17% for the area under the BIS time curve from time 0-60 min after administration (BISAUC0-60 min), respectively. The 90% CI of these pharmacokinetic and pharmacodynamic parameters all fall in the accepted bioequivalence range of 80.00-125.00%. No serious adverse events occurred during the study. This study has shown that the etomidate fat emulsion test and reference formulation had similar pharmacokinetic and pharmacodynamic characteristics in vivo. The two formulations exhibited good safety and well-tolerance.Clinical trials registration number: http://www.chinadrugtrials.org.cn/index.html . # CTR20191836.

Safety, Tolerability, and Pharmacokinetic Study of 101BHG-D01 Nasal Spray, a Novel Long-Acting and Selective Cholinergic M Receptor Antagonist, in Healthy Chinese Volunteers: A Randomized, Double-Blind, Placebo-Controlled, Single-Dose Escalation, First-In-Human Study.

BACKGROUND AND OBJECTIVE: 101BHG-D01 nasal spray is the first novel long-acting cholinergic M receptor antagonist under development to treat rhinorrhea in rhinitis. This first-in-human study aimed to evaluate the safety, tolerability, and pharmacokinetics of 101BHG-D01 nasal spray following single intranasal doses in healthy Chinese subjects. METHODS: A randomized, double-blind, placebo-controlled, single-dose escalation study was conducted in healthy Chinese volunteers after intranasal doses of 101BHG-D01 nasal spray or placebo ranging from 40 µg to 960 µg (total of six doses). Blood samples were collected at scheduled time points, and plasma concentrations were determined using a validated high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method. A non-compartmental method was used to calculate the main pharmacokinetic parameters, including the area under the plasma concentration-time curve from time zero to the time of the last measurable concentration (AUC0-t), the area under the plasma concentration-time curve from time zero to infinity (AUC0-∞), the maximum plasma concentration (Cmax), the time to maximum plasma concentration (Tmax), and the elimination half-life (t1/2). Safety was evaluated by monitoring adverse events, laboratory assays, vital signs, physical examinations, 12-lead electrocardiograms (ECGs), anterior rhinoscopy, ophthalmic examination, and ambulatory ECG monitoring. RESULTS: Following single intranasal dosing, 101BHG-D01 was rapidly absorbed with a median Tmax of 0.34-0.50 h and eliminated slowly with a mean t1/2 ranging from 4.29 to 46.76 h for different dose groups. The Cmax and AUC of 101BHG-D01 increased linearly across the examined dose range of 40-960 µg. 101BHG-D01 nasal spray was well tolerated, all AEs were mild, and no serious adverse events occurred during the study. CONCLUSIONS: 101BHG-D01 nasal spray was safe and well tolerated in healthy Chinese subjects when administered intranasally in single escalating doses. The mean Cmax and AUC increased proportionally to the studied dose. The pharmacokinetic, safety, and tolerability profiles of 101BHG-D01 nasal spray indicate that it is a good candidate for further development as a treatment for rhinorrhea in rhinitis.

Bioequivalence Study of Palbociclib Capsules in Healthy Chinese Subjects Under Fasting and Fed Conditions.

BACKGROUND AND OBJECTIVE: Palbociclib is an oral small-molecule inhibitor of cyclin-dependent kinase 4/6 used for the treatment of advanced breast cancer. This study compared the pharmacokinetic and safety profiles between a new generic and a branded reference formulation of palbociclib capsules in healthy Chinese subjects under fasting and fed conditions and evaluated the bioequivalence of two palbociclib products to obtain sufficient evidence for the marketing approval of the new generic drug. METHODS: A randomized, open-label, two-period crossover study was conducted in healthy Chinese volunteers under both fasting and fed conditions (30 subjects/condition). Eligible healthy subjects received a single 125-mg dose of the palbociclib test or reference formulation followed by a 14-day washout period. Serial blood samples were collected at scheduled timepoints, and plasma concentrations were determined by a validated high-performance liquid chromatography-tandem mass spectrometry method. A non-compartment method was used to calculate the main pharmacokinetic parameters, including the area under the plasma concentration-time curve (AUC) from time 0 to the time of the last measurable concentration (AUC0-t), the AUC from time 0 to infinity (AUC0-∞), the maximum plasma concentration (Cmax), the time to maximum plasma concentration, and the elimination half-life. The geometric mean ratios and the corresponding 90% confidence intervals of palbociclib were acquired for the bioequivalence analysis. Safety and tolerability were assessed by monitoring adverse events, laboratory assessments, vital signs, physical examinations, and 12-lead electrocardiograms. RESULTS: Under the fasting condition, the pharmacokinetic parameter values of the test formulation were similar to those of the reference formulation. The 90% confidence intervals of geometric mean ratios of the test to reference formulations were 94.35-103.82% for Cmax, 94.79-103.26% for AUC0-t, and 94.82-103.38% for AUC0-∞, which are all within the accepted bioequivalence range of 80.00-125.00%. Meanwhile, under the fed condition, the pharmacokinetic parameter values of the test formulation were also similar to those of the reference formulation. The 90% confidence intervals of geometric mean ratios of the test to reference formulations were 96.65-103.56% for Cmax, 98.06-103.61% for AUC0-t, and 97.88-103.46% for AUC0-∞, which are all within the accepted bioequivalence range of 80.00-125.00%. The test and reference products were well tolerated, and no serious adverse events occurred during the study. CONCLUSIONS: Pharmacokinetic bioequivalence of palbociclib in healthy subjects was established between the palbociclib test formulation and the reference formulation under fasting and fed conditions according to predetermined regulatory criteria. The two formulations were safe and well tolerated.

Pharmacokinetics and safety of ezetimibe/simvastatin combination tablet: an open-label, single-dose study in healthy Chinese subjects.

BACKGROUND AND OBJECTIVES: Ezetimibe/simvastatin combination tablet has been approved for the treatment of high low-density lipoprotein cholesterol (LDL-C) levels in patients with primary hypercholesterolaemia or mixed hypercholesterolaemia as adjunctive therapy to diet, when diet alone is insufficient in lowering cholesterol. The aims of this study were to assess the pharmacokinetics and safety of an ezetimibe/simvastatin combination tablet after oral single-dose administration in healthy Chinese subjects including sex-related differences in pharmacokinetics. METHODS: This was an open-label, single-dose study. Twelve healthy subjects (six males and six females) received a single dose of an ezetimibe/simvastatin combination tablet (ezetimibe 10 mg and simvastatin 40 mg). The pharmacokinetic parameters for ezetimibe and simvastatin were assessed by determining total ezetimibe, free ezetimibe, simvastatin and simvastatin acid concentrations using a validated liquid chromatography-tandem mass spectrometry method. Safety was evaluated by monitoring adverse events, laboratory assays, vital signs, physical examinations and 12-lead electrocardiograms. RESULTS: The pharmacokinetic parameters (mean ± SD) for total ezetimibe and free ezetimibe following a single dose were: maximum plasma drug concentration (C(max)) 81.56 ± 26.62 and 9.40 ± 6.17 ng/mL; time to reach C(max) (t(max)) 0.93 ± 0.30 and 1.25 ± 1.27 h; elimination half-life (t(½)) 24.32 ± 13.27 and 18.90 ± 9.66 h, and mean area under the plasma concentration-time curve from time zero to the time of the last measurable concentration (AUC(last)) 579.06 ± 241.45 and 126.01 ± 69.01 ng·h/mL, respectively. The pharmacokinetic parameters (mean ± SD) for simvastatin and simvastatin acid following a single dose were: C(max) 11.92 ± 5.50 and 3.37 ± 1.78 ng/mL, t(max) 0.98 ± 0.28 and 3.73 ± 1.68 h, t(½) 4.19 ± 1.81 and 7.65 ± 7.96 h, and mean AUC(last) 33.63 ± 20.41 and 32.50 ± 18.79 ng·h/mL. Higher AUC(last) and AUC from time zero to infinity (AUC(∞)), and lower apparent total body clearance of drug from plasma after oral administration (CL/F) for total ezetimibe and free ezetimibe were observed in female subjects compared with those in male subjects. There were no differences between the pharmacokinetic parameters of simvastatin and simvastatin acid for female and male subjects in the study. CONCLUSION: Ezetimibe/simvastatin combination tablet has a generally favourable safety and tolerability profile in healthy Chinese subjects. A statistically significant difference with regard to sex in the pharmacokinetics of ezetimibe was observed. Sex had no effect on the pharmacokinetics of simvastatin and simvastatin acid.

The effect of CYP2C19 activity on pharmacokinetics of lansoprazole and its active metabolites in healthy subjects.

CONTEXT: Lansoprazole is a gastric proton-pump inhibitor and has been demonstrated to be effective in the treatment of various peptic diseases. The effects of CYP2C19 activity on the pharmacokinetics of lansoprazole and its active metabolites in Chinese subjects have not previously been evaluated. OBJECTIVE: The study aimed to evaluate the effects of CYP2C19 activity in healthy Chinese volunteers. MATERIALS AND METHODS: Twenty-two healthy volunteers were recruited for an open trial and received a single dose of 30 mg lansoprazole. Using a validated LC-MS/MS method, we measured the plasma concentrations of lansoprazole, 5-hydroxylansoprazole, and lansoprazole sulfone. The genotype of CYP2C19 was identified by polymerase chain reaction (PCR) analysis of single nucleotide polymorphisms (SNPs). Subjects were genotypically classified into the following three groups on the basis of PCR-SNP analysis for CYP2C19: homozygous EM (hmEM) group, heterozygous EM (htEM) group, and PM group. To test differences in pharmacokinetic parameters among the three groups, analysis of variance (ANOVA) after log-transformation of data was used. RESULTS AND CONCLUSION: Our results indicated that there were significant differences (p < 0.001) between the hmEM and PM groups, between the htEM and PM groups, and between the hmEM and htEM groups in C(max), AUC(0-t), and AUC(0-inf) of lansoprazole and lansoprazole sulfone. There were also significant differences (p < 0.001) between the hmEM and PM groups, and between the htEM and PM groups in C(max) of 5-hydroxylansoprazole.

Pharmacokinetics of rosuvastatin in healthy Chinese volunteers living in China: a randomized, open-label, ascending single- and multiple-dose study.

BACKGROUND: Cross-study comparisons suggest that systemic exposure (AUC) to rosuvastatin calcium, a 3-hydroxy-3-methylglutaryl coenzyme A-reductase inhibitor, may be approximately 2-fold higher in Asian subjects living in Asian countries than in white subjects living in Western countries. OBJECTIVE: This study was conducted to determine the pharmacokinetic characteristics of rosuvastatin and its metabolites after single and multiple doses of rosuvastatin in healthy Chinese subjects living in China. METHODS: This was an open-label, ascending single- and multiple-dose study. Subjects were randomly assigned to receive rosuvastatin 5, 10, or 20 mg. Each subject received 1 tablet of the assigned treatment on day 1 and days 4 through 10. Plasma concentrations of rosuvastatin, N-desmethyl rosuvastatin, and rosuvastatin lactone were measured through 72 hours after administration of single doses and through 96 hours after administration of multiple doses. Blood samples were obtained within 30 minutes before dosing on days 7, 8, and 9 for the assessment of pharmacokinetic parameters at steady state. Noncompartmental pharmacokinetic analysis was performed to determine the C(max) and AUC(0-t) for rosuvastatin, N-desmethyl rosuvastatin, and rosuvastatin lactone after single and multiple doses of rosuvastatin. Tolerability assessments were conducted throughout the study. RESULTS: Of the 36 enrolled subjects, only 1 was female. The mean age of subjects in the rosuvastatin 5-, 10-, and 20-mg groups was 22.4, 21.3, and 22.4 years, respectively. Weight and height ranged from 54 to 85 kg and from 161 to 189 cm, respectively. Geometric mean C(max) values for rosuvastatin after administration of single doses of rosuvastatin 5, 10, and 20 mg were 8.33, 10.76, and 19.17 ng/mL, respectively; the corresponding geometric mean AUC(0-t) values were 57.63, 88.89, and 163.87 ng . h/mL. At steady state, values for C(max) were 8.31, 8.41, and 20.73 ng/mL; the corresponding geometric mean AUC values were 64.87, 77.29, and 178.64 ng . h/mL. After administration of multiple doses of rosuvastatin 5, 10, and 20 mg, the accumulation ratios were 1.23, 0.95, and 1.23, respectively, indicating minimal accumulation of rosuvastatin. Circulating concentrations of N-desmethyl rosuvastatin and rosuvastatin lactone were well below those of rosuvastatin after administration of single and multiple doses of rosuvastatin. CONCLUSIONS: Increases in C(max), AUC(0-t), C(max,ss), and AUC(ss) were observed with increasing single and multiple doses of rosuvastatin 5, 10, and 20 mg. The increase in exposure with increasing doses was lower than would be expected under conditions of strict proportionality. Rosuvastatin exhibited little accumulation on repeated administration. All rosuvastatin doses were well tolerated in these Chinese subjects.

Matrine determination and pharmacokinetics in human plasma using LC/MS/MS.

A liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was developed for the determination of matrine in human plasma extracted by isopropanol:ethyl acetate (v/v, 5:95). Rapid chromatographic separation was achieved in the mobile phase composition of 5-mM aqueous ammonium acetate and acetonitrile (v/v, 70:30) with a flow rate of 0.20ml/min. Detection was carried out using positive-ion electrospray tandem mass spectrometry on a Sciex API3000. The method was accurate, specific and sensitive for the analysis of matrine in human plasma in the concentration range of 5-2000ng/ml, when huperzine A was used as internal standard. The method facilitated a clinical pharmacokinetic study after oral administration of a single dose of matrine soft gelatin capsules (100, 200 and 400mg) in a three-period crossover design. Dose-related linear trends were observed for the AUC(0-t) and the C(max) of matrine. The t(1/2) and the T(max) of matrine were independent of the administered doses.

Pharmacokinetics of orally administered single- and multiple-dose olopatadine in healthy Chinese subjects: an open-label study.

BACKGROUND AND OBJECTIVES: Olopatadine is a new selective histamine H(1) receptor antagonist with anti-inflammatory and anti-allergic effects. Its pharmacokinetics and safety have not previously been evaluated in Chinese subjects. The aims of this study were to assess the pharmacokinetics and safety of olopatadine after single- and multiple-dose oral administration in healthy Chinese subjects and to identify any differences in pharmacokinetics between males and females. METHODS: The pharmacokinetic parameters for olopatadine in 12 healthy Chinese subjects (six males and six females) were assessed by determining olopatadine concentrations with a validated liquid chromatography-tandem mass spectrometry method. Safety and tolerability were evaluated by monitoring adverse events, laboratory assay results, vital signs, physical examination findings and 12-lead ECG results. RESULTS: The pharmacokinetic parameters (mean +/- SD) for olopatadine following a single dose were: maximum plasma concentration (C(max)) 69.98 +/-20.87 ng/mL, time to reach C(max) (t(max)) 1.02 +/- 0.34 h, elimination half-life (t1/2) 5.87 +/- 4.24 h, area under the plasma-concentration curve (AUC) from time zero to the time of last quantifiable concentration (AUC(last)) 266.00 +/- 143.95 ng.h/mL, AUC from time zero extrapolated to infinity (AUC(infinity)) 283.46 +/- 152.96 ng.h/mL, apparent oral clearance (CL/F) 23.45 +/- 12.59 L/h and apparent volume of distribution after oral administration (V(d)/F) 133.83 +/- 43.07 L. The pharmacokinetic parameters of olopatadine after multiple doses were similar to those after a single dose. In both studies, significantly higher AUC(last), AUC(infinity) and C(max), longer t1/2 (single-dose only) and lower CL/F were observed in female subjects compared with male subjects after both single and multiple dosing. No serious adverse events occurred. CONCLUSION: Olopatadine was shown to be safe and well tolerated in healthy Chinese subjects. There were no changes in absorption and elimination of olopatadine following multiple doses and no accumulation was found. Possible sex-related differences in absorption and elimination of olopatadine were observed.

Simultaneous determination of desloratadine and its active metabolite 3-hydroxydesloratadine in human plasma by LC/MS/MS and its application to pharmacokinetics and bioequivalence.

A rapid and simple liquid chromatographic-tandem mass spectrometric (LC/MS/MS) method was developed and validated for the simultaneous determination of desloratadine and its active metabolite 3-hydroxydesloratadine concentrations in human plasma. After liquid-liquid extraction with ethyl ether for sample preparation, the chromatographic separation was achieved on a CAPCELL PAK C18 column (50 mm x 2.0mm, 5 microm, Shiseido). [(2)H(4)]desloratadine and [(2)H(4)]3-OH desloratadine were used as internal standards. A mobile phase consisted of 5mM ammonium formate in water, methanol and acetonitrile (50:30:20). Detection was by positive ion electrospray tandem mass spectrometry on a Sciex API3000. A quadratic regression (weighted 1/concentration) gave the best fit for calibration curves over the concentration range 0.05-10 ng/mL for both desloratadine and 3-OH desloratadine. The method was shown to be accurate, rapid and sufficiently sensitive to be successfully applied to a pharmacokinetic and bioequivalent study.

Determination of eprosartan in human plasma and urine by LC/MS/MS.

A protein precipitation, liquid chromatography/tandem mass spectrometry (LC/MS/MS) method has been developed and validated for the determination of eprosartan in human plasma and urine. The solvent system also served as a protein precipitation reagent. The chromatographic separation was achieved on a CAPCELL PAK C18 column (50 mmx2.0 mm, 5 microm, Shiseido). A mobile phase was consisted of 0.5% formic acid in water and 0.5% formic acid in acetonitrile (72:28). Detection was by positive ion electrospray tandem mass spectrometry on a Sciex API3000. The standard curves, which ranged from 5 to 2000 ng/mL in human plasma and from 0.25 to 50 microg/mL in urine, were fitted to a 1/x weighted quadratic regression model. The method proved to be accurate, specific and sensitive enough to be successfully applied to a pharmacokinetic study.

A sensitive assay for simultaneous determination of plasma concentrations of valganciclovir and its active metabolite ganciclovir by LC/MS/MS.

A protein precipitation, liquid chromatography/tandem mass spectrometry (LC/MS/MS) method has been developed and validated for the simultaneous determination of valganciclovir and its active metabolite ganciclovir in human plasma. The solvent system also served as a protein precipitation reagent. The chromatographic separation was achieved on an Aquasil C18 column (50 mm x 2.1mm, 5 microm). A linear gradient mobile phase between 0.02% formic acid and methanol was used. Detection was by positive ion electrospray tandem mass spectrometry on a Sciex API3000. The standard curves, which ranged from 4 to 512 ng/mL for valganciclovir and from 0.1 to 12.8 microg/mL for ganciclovir, were fitted to a 1/x weighted quadratic regression model. The method was proved to be accurate, specific and sensitive enough and was successfully applied to a pharmacokinetic study.