| Description | Apixabanisahighlyselective,reversibleinhibitorofFactorXawithKiof0.08nMand0.17nMinhumanandrabbit,respectively. |
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| IC50&Target | IC50:0.08nM(HumanFactorXa),0.17nM(RabbitFactorXa) |
| InVitro | Apixabanexhibitsahighdegreeofpotency,selectivity,andefficacyonFactorXawithKiof0.08nMand0.17nMforHumanFactorXaandRabbitFactorXa,respectively[1].Invitro,Apixabanprolongstheclottingtimesofnormalhumanplasmawiththeconcentrations(EC2x)of3.6μM,0.37μM,7.4μM,and0.4μM,whicharerequiredrespectivelytodoubletheprothrombintime(PT),modifiedprothrombintime(mPT),activatedpartialthromboplastintime(APTT)andHepTest.Besides,Apixabanshowsthehighestpotencyinhumanandrabbitplasma,butlesspotencyinratanddogplasmainboththePTandAPTTassays[2]. |
| InVivo | Apixabanshowstheexcellentpharmacokineticswithverylowclearance(Cl:0.02L/kg/h),andlowvolumeofdistribution(Vdss:0.2L/kg)inthedogs.Besides,Apixabanalsoexhibitsamoderatehalf-life(T1/2:5.8hours)andgoodoralbioavailABIlity(F:58%)[1].Inthearteriovenous-shuntthrombosis(AVST),venousthrombosis(VT)andelectricallymediatedcarotidarterialthrombosis(ECAT)rabbitmodels,Apixabanproducesdose-dependentantithromboticeffectswithEC50of270nM,110nMand70nM,respectively[2].ApixabansignificantlyinhibitsfactorXaactivitywithIC50of0.22μMinrabbitexvivo[3].Inchimpanzee,Apixabanalsoshowssmallvolumeofdistribution(Vdss:0.17L/kg),lowsystemicclearance(Cl:0.018L/kg/h),andgoodoralbioavailability(F:59%)[4]. |
| ClinicalTrial | ViewMoreCollapse |
| References |
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| PreparingStockSolutions |
Pleaserefertothesolubilityinformationtoselecttheappropriatesolvent. | ||||||||||||||||
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| KinaseAssay [2] | PurifiedFXaisobtainedafteractivationwithRussell’svipervenomfollowedbyaffinitychromatography.TheresultingFXais>95%pureasjudgedbysodiumdodecylsulfatepolyacrylamidegelelectrophoresis.ThesubstrateaffinityvaluesforFXa,expressedastheMichaelis-Menten-Henriconstant(Km),forhuman,rabbit,ratanddogFXaaredeterminedusingthechromogenicsubstrateS-2765,andare36,60,240and70μM,respectively.Thesubstratehydrolysisismonitoredbymeasuringabsorbanceat405nmat25°Cforupto30minusingaSpectraMax384PlusplatereaderandSoftMax.FXaactivityforeachsubstrateandinhibitorconcentrationpairisdeterminedinduplicate.TheKivaluesarecalculatedbynon-linearleast-squaresfittingofthesteady-statesubstratehydrolysisratestotheequationforcompetitiveinhibition(Equation1)usingGRAFIT,wherevequalsreactionsvelocityinODmin−1,Vmaxequalsmaxiumumreactionvelocity,Sequalssubstrateconcentration,andIequalsinhibitorconcentration.MCEhasnotindependentlyconfirmedtheaccuracyofthesemethods.Theyareforreferenceonly. | ||||||||||||||||
| AnimalAdmiNISTration [2] | Apixabanisformulatedinvehicle(10%N,N-dimethylacetamide;30%1,2-propanediol;60%water). Briefly,maleNewZealandWhiterabbitsareanesthetizedwithketamine(50mg/kgi.m.)andxylazine(10mg/kgi.m.),andtheirfemoralartery,jugularveinandfemoralveinarecatheterized.Theseanestheticsaresupplementedasneeded.Thrombosisisinducedbyanarteriovenous(AV)-shuntdevicecontainingasilkthread.BloodflowedfromthefemoralarteryviatheAVshuntintotheoppositefemoralveinfor40min.Theshuntisthendisconnectedandthesilkthreadcoveredwiththrombusisweighed.Asapixabanhasanoralbioavailabilityof<5%=""in=""rabbits=""(unpublished=""result),=""it=""is=""administered=""intravenously=""for=""in=""vivo=""studies.=""to=""achieve=""a=""stable=""plasma=""level=""with=""minimum=""experimental=""variability,=""apixaban,=""fondaparinux=""or=""vehicle=""is=""given=""by=""a=""continuous=""intravenous=""infusion=""1=""h=""prior=""to=""shunt=""placement.=""the=""infusion=""is=""continued=""throughout=""the=""experiment.=""warfarin=""or=""vehicle=""is=""dosed=""orally=""once=""daily=""for=""4=""days.=""on=""the=""fourth=""day=""after=""the=""last=""oral=""dose=""of=""warfarin=""or=""vehicle,=""rabbits=""are=""anesthetized=""1.5=""h=""later,=""and=""the=""treatment=""effect=""is=""evaluated=""about=""2=""h=""postdose.=""arterial=""blood=""samples=""for=""the=""determination=""of=""clotting=""times=""or=""plasma=""levels=""are=""collected=""20=""min=""after=""shunt=""placement.=""plasma=""levels=""of=""apixaban=""are=""measured=""by=""a=""specific=""and=""sensitive=""liquid=""chromatographic=""mass=""spectrometry=""method=""(lc/ms/ms).=""in=""rabbits=""treated=""with=""apixaban,=""fondaparinux=""or=""warfarin,=""the=""antithrombotic=""effects=""of=""these=""agents=""are=""expressed=""as=""percentage=""inhibition=""of=""thrombus=""formation=""based=""on=""the=""treated=""vs.=""the=""corresponding=""mean=""vehicle.=""the="">50value(dosethatproduced50%inhibitionofthrombusformation)isdeterminedasdescribedbelow.Theapixabangrouptreatmentconsistsofvehicle(10%N,N-dimethylacetamide;30%1,2-propanediol;60%water)(n=4),andapixaban(mg/kg/h)at0.03(n=7),0.1(n=7),0.3(n=7),1(n=7),and3(n=3).Thefondaparinuxgrouptreatmentconsistsofvehicle(saline)(n=6),andfondaparinux(mg/kg/h1)at0.01(n=5),0.03(n=5),0.1(n=5),0.3(n=5),and1(n=5).Thewarfaringrouptreatmentconsistsofvehicle(water)(n=6),andwarfarin(mg/kg/day)at0.1(n=6),0.3(n=6),1(n=6),and3(n=6).MCEhasnotindependentlyconfirmedtheaccuracyofthesemethods.Theyareforreferenceonly. | ||||||||||||||||
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| MolecularWeight | 459.5 | ||||||||||||
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| Formula | C₂₅H₂₅N₅O₄ | ||||||||||||
| CASNo. | 503612-47-3 | ||||||||||||
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| Shipping | RoomtemperatureincontinentalUS;mayvaryelsewhere | ||||||||||||
| Solvent&Solubility | DMSO:14.25mg/mL;H2O：<0.1=""> *"<1 mg/ml"="" means="" slightly="" soluble="" or="" insoluble.="" "≥"="" means="" soluble,="" but="" saturation=""> Purity:99.97% |
