Studies On Pharmacokinetics Of Pantoprazole Enantiomers And Drug To Drug Interaction Of Drug Combination

Pantoprazole is the third proton pump inhibitor（PPI）after omeprazole and lansoprazole.It is for the treatment of gastroesophageal reflux disease associated with a history of erosive esophagitis as well as pathological hypersecretion conditions in clinical.Pantoprazole metabolism is mediated by CYP450 in vivo.The major metabolite of pantoprazole is demethylation sulphate pantoprazole.Most excreted by kidneys and others excreted by feces.Same as omeprazole and lansoprzzole,the pharmacokinetic of pantoprazole enantiomers was difference in vivo.So,it’s necessary to study the pharmacokinetics of pantoprazole enantiomers in human.Pantoprazole was the major objective in the study,using the overlapping injection model firstly,established a high throughput LC-MS/MS method to separation the enantiomeric of pantoprazole in 5 mins.Using Panpure IV as reference and the domestic pantoprazole as test,the pharmacokinetics in Chinese volunteer was studied for the first time.Since the high incidence and long treatment cycle of gastrointestinal and hyperlipidemia disease,these two drugs always needs to combinated used in clinical.And it is reported that pantoprazole may interference the metabolism of statins.Atorvastatin is the major durg of statins.Therefore,the study establish an LC-MS/MS method firstly to determination the pantoprazole and atorvastatin in rat plasma,to support a pharmacokinetic study about the combination of pantoprazole and atorvastatin in rat.The results would provide reference for clinical drug usage.The detailed research of the paper was presented as follows:1.LC-MS/MS method validation for determination of pantoprazole enantiomers in human plasmaA sensitive and high-throughput chiral liquid chromatography-tandem mass spectrometry method was developed and validated for the quantification of R-pantoprazole and S-pantoprazole in human plasma.Sample extraction was carried out by 96-well plate format using ethyl acetate liquid–liquid extraction in 96-well plate formatusing ethyl acetate.The separation of pantoprazole enantiomers was performed on a CHIRALCEL OJ-RH column and an overlapping injection mode was used to achieve run time of 5.0 min/sample.The mobile phase consisted of（A）10 mM ammonium acetate in methanol:acetonitrile（1:1,v/v）and（B）20 mM ammonium acetate in water.Isocratic elution was used with flow rate at 500μL/min.The enantiomers were quantified on a triple-quadrupole mass spectrometer under multiple reactions monitoring（MRM）mode with m/z 382.1→230.0 for pantoprazole and m/z 388.4→230.1 for pantoprazole-d7.Linearity from 20.0 to 5000 ng/mL was established for each enantiomer（r²>0.99）.Extraction recovery were large than 90%.The method was demonstrated with acceptable accuracy,precision within 15%.By using an overlapping injection mode,the run time was reduced to be 5.0 min per sample.It is the most rapid method at present.2.Pharmacokinetics of pantoprazole enantiomers in humanA single center,single armed,multidoses study was performed to investigate the pharmacokinetics of S-pantoprazole in 12 health Chinese volunteer（half male and half female）.The test drug form domestic and the reference durg is Pantoloc.The major pharmacokinetic parameters were calculated with non compartment model.The major parameters of 10 mg group is AUC_0-12 1816.12±636.69 h·ng/mL,C_max 1240±299.52ng/mL,T_max 0.25±0.00 h,t_1/2 1.37±0.46 h,MRT 1.63±0.48 h,20 mg group AUC_0-12-12 is3758.93±1624.20 h·ng/mL,C_maxax 2500±389.84 ng/mL,T_max 0.25±0.00 h,t_1/2 1.52±0.50 h,MRT 1.69±0.57 h,40 mg group AUC_0-12 6315.40±2664.39 h·ng/mL,C_maxax 4330±1357.70ng/mL,T_max 0.25±0.00 h,t_1/2 1.67±0.60 h,MRT 1.76±0.56 h,80 mg group AUC_0-1214608.20±5172.57 h·ng/mL,C_maxax 10000±2908.56 ng/mL,T_maxax 0.25±0.00 h,t_1/2 1.94±0.61h,MRT 1.93±0.52 h,the pharmacokinetic result shows that,in range of 10-80 mg dose,there is a obvious linear relationship between dose and AUC_0-12-12 and C_max,and no significant difference between male and female volunteer,variation of dose has no impact on the pharmacokinetic parameters of T_max,t1/2 and MRT.3.Simultaneous determination of pantoprazole and atorvastatin in rat plasma using LC-MS/MSA liquid chromatography-tandem mass spectrometry method was developed and validated for the quantification of pantoprazole and atorvastatin in rat plasma.Sample extraction was carried out by 96-well plate format using protein precipitation extraction in 96-well plate.The separation of pantoprazole and atorvastatin was performed on a CAPCELL PAK MG C18（2.0 mm×50 mm,5μm）column.The mobile phase consisted of（A）0.1%of acetic acid in water and（B）0.1%of acetic acid in methanol.Gradient elution was used with flow rate at 300μL/min.The compounds were quantified on a triple-quadrupole mass spectrometer under multiple reactions monitoring（MRM）mode with m/z 384→200 for pantoprazole,m/z 559.4→440.2 for atorvastatin and m/z346.2→198.2 for omeprazole（IS）,m/z 564.3→445.1 for atorvastatin-d5（IS）.Linearity from 20.0 to 5000 ng/mL was established for pantoprazole and 1.00²50 ng/mL for atorvastatin.Extraction recovery were large than 90%.The method was demonstrated with acceptable accuracy,precision within 15%.4.Studies on pharmacokinetic interaction between pantoprazole and atorvastatinTo investigate the durg to drug interaction when combination of pantoprazole and atorvastatin,18 wistar rars were divided into 3 groups randomly,six in each group.The first group was given an oral of 5 mg/kg pantoprazole,the second group was given an oral of 10 mg/kg atorvastatin,and the third group were given a combination of pantoprazole and atorvastatin.The validated LC-MS/MS method was used to determine the concentration of pantoprazole and atorvastatin.The interaction of drug combination was evaluated by pharmacokinetic parameters.The C_max and AUC_0-t values of single drug group and combined drugs group for pantoprazole were 2583±650 ng/mL,2853±971 h·ng/mL and 3942±623 ng/mL,4483±951h·ng/mL,the C_max and AUC_0-t values of single drug group and combined drugs group for atorvastatin were 57.0±10.5 ng/mL,100±21.9 h·ng/mL and 63.7±23.4 ng/mL,115±35.8h·ng/mL.The results herein showed the significant difference appears in the C_max and AUC_0-tof pantoprazole between two groups.There is no significant difference in atorvastatin.5.Studies on pharmacokinetic interaction between pantoprazole and mosaprideA liquid chromatography-tandem mass spectrometry method was developed and validated for the quantification of mosapride in rat plasma.Sample extraction was carried out by 96-well plate format using protein precipitation extraction in 96-well plate.The separation of mosapride was performed on a CAPCELL PAK MG C18（2.0 mm×50 mm,5μm）column.The mobile phase consisted of（A）0.1%of acetic acid in water and（B）0.1%of acetic acid in methanol.Gradient elution was used with flow rate at 300μL/min.The compounds were quantified on a triple-quadrupole mass spectrometer under multiple reaction monitoring（MRM）mode with m/z 422.7→198.3 for mosapride and m/z428.1→203.3 for mosapride-d5.Linearity from 0.200 to 100 ng/mL was established.Extraction recovery were large than 98%the method was demonstrated with acceptable accuracy,precision within 15%.To investigate the durg to drug interaction when combination of pantoprazole and mosapride,18 wistar rars were divided into 3 groups randomly,six in each group.The first group was given an oral of 5 mg/kg pantoprazole,the second group was given an oral of 10 mg/kg mosapride,and the third group were given a combination of pantoprazole and mosapride.The validated LC-MS/MS method was used to determine the concentration of pantoprazole and mosapride.The interaction of drug combination was evaluated by pharmacokinetic parameters.The C_max and AUC_0-t values of single drug group and combined drugs group for pantoprazole were 3015±752 ng/mL,2758±846 h·ng/mL and 4450±2157 ng/mL,5007±2434 h·ng/mL,the C_max and AUC_0-t-t values of single drug group and combined drugs group for mosapride were 218±156ng/mL,355±171 h·ng/mL and 99.8±69.6 ng/mL,243±124 h·ng/mL.The results herein showed there is no significant difference appears between two groups.