| OBJECTIVE1. To establish a HPLC-MS/MS method to determinate imrecoxib MO, its hydroxyl metabolites M1and its carboxylic acid metabolite M2concentrations in human plasma;2. To evaluate the pharmacokinetic (PK) parameters of imrecoxib and its two metabolites in subjects with normal function and severe renal impairment, and to provide reference for clinical medication when renal dysfunction is present.METHODS1. Development of HPLC-MS/MS:our study used liquid phase extraction for the pretreatment, and diazepam was used as the internal standard. Chromatographic separation was performed on a EcLipse XDB-C18(1502.1mm,3.0μm).The mobile phase was0.1%formic acid aqueous/0.1%formic acid methanol solution with a volume ratio of3:7and the flow rate of the mobile phase was0.3mL·min-1. The analytes were monitored by a API4000tandem-mass spectrometry with positive electro spray ionization. The multiple reaction monitoring (MRM) transitions were preformed at m/z390.2'236.1for M0, m/z386.1'236.1for M1, m/z400.1'236.1for M2and m/z368.4'294.0for IS.2. Pharmacokinetic study:this was a parallel, open-label, single period, match group study.12patients with sever renal impairment were enrolled according to the include/exclude standard. The12healthy controls to be selected to ensure that they were comparable with subjects with sever renal impairment for age (±5, years), sex, weight (±15%, Kg). A series of blood samples were collected from all subjects at different time after a postprandial single dose oral of100-mg imrecoxib.A verified LC-MS/MS method was established to quantitative analysis for MO, M1and M2in human plasma. WinNonlin software was used to calculate the PK parameters of imrecoxib, M1and M2, t test and Wilcoxon test were used for the variance analysis of the two group’s noncompartment parameters. Correlation analysis was conducted between renal function index creatinine clearance (Ccr) and the main PK parameters of M0, M1and M2.RESULTS1. Methodological evaluation results:The typical chromatographic retention time of M0, M1, M2and IS were2.36min,1.49min,1.53min and3.62min, respectively. The method was validated by accuracy, precision, recovery, matrix effects and stable tests. Plasma MO, Ml and M2concentration was found to be linear over the range of0.1-100,0.2-200and2-2000ng·mL-1, respectively. LLOQ was0.1,0.2and2ng·mL-1.2. Pharmacokinetics results:(1) In renal impairment, the main PK parameter Cmax of M0、M1and M2were (22.63±16.89),(71.69±16.79) and (1671.66±576.41) ng·h·mL-1; Tmax were (3.50±1.45),(3.50±1.45) and (4.00±1.65) h; t1/2were (11.89±7.79),(25.95±23.68) and (13.41±8.11) h; AUC(0't) were (183.38±125.50),(647.46±213.74) and (18465.38±8602.21) ng·h·mL-1; AUC(0'∞)were (195.33±135.41),(665.27±220.48) and (18581.15±8579.05) ng·h·mL-1; CL/F were (1056.38±180.75),(169.24±69.68) and (6.62±3.47) L·h-1; V/F were (15850.91±18444.30),(5586.51±4548.44) and (135.36±110.86) L; MRT(0't) were (10.14±2.71),(18.12±7.63) and (13.31±4.78) h.(2) In healthy volunteers, the main PK parameter Cmax of M0、M1and M2were (59.94±50.55),(71.96±15.07) and (585.18±190.01) ng·h·mL-1; Tmax were (2.63±1.07),(2.75±0.87) and (2.67±0.78) h; t1/2were (8.02±2.97),(8.16±4.76) and (8.00±3.66) h; AUC(0't) were (477.01±395.73),(518.58±145.16) and (3855.25±995.14) ng·h·mL-1; AUC(0'∞)were (479.39±395.62),(523.37±144.75) and (3930.04±1018.54) ng·h·mL-1; CL/F were (1056.38±180.75),(169.24±69.68) and (6.62±3.47) L·h-1; V/F were (463.67±463.06),(205.57±59.68) and (306.58±138.86) L; MRT(0't) were (9.31±2.75),(8.46±2.12) and (8.83±2.76) h. When compared with healthy volunteers, the AUC and Cmax of M0in renal impairment was significant declined (P<0.05); the AUC and Cmax of M1in renal impairment was increased, but the difference were not significant (P>0.05), t1/2, Tmax, V/F and MRT(0-t) were significant increased (P<0.05); the t1/2, Tmax, MRT(0-t), AUC and Cmax, V/F, CL/F of M2were both dramatically increased (P<0.05). Correlation analysis indicated that M2CL/F was highly negative correlated with Ccr (r=0.8665,P<0.05).CONCLUSION1. The developed HPLC-MS/MS method in our study to determinate the M0, M1and M2concentations in human plasma showed well accurate, specific and sensitive, and the method was successfully applied for our pharmacokinetic study;2. The systemic exposure and elimination half-life of MO’s two active metabolites were significantly lager, and the clearance was significantly lower compared with the healthy subjects. Dose adjustment may be necessaty for the patients with sever renal impairment. |
PDF Full Text Request