Medchemexpress/Avibactam sodium(Synonyms: NXL-104)/HY-14879A/5mg

Avibactamsodiumisacovalent,reversibleβ-lactamaseinhibitor,inhibitsβ-lactamaseTEM-1andCTX-M-15withIC₅₀of8nMand5nM,respectively.

IC50:8nM(TEM-1),5nM(CTX-M-15)^[1]

Avibactam(NXL104)sodiumisamoleculewithlittleantibacterialactivity,thatinhibitsclassAandCβ-lactamases.Avibactaminactivatesmostimportantβ-lactamasesexceptmetallotypesandAcinetobacterOXAcarbapenemases^[2].

Avibactamsodiumdisplaysaslowreturnofactivitywithanoff-rateof0.045±0.022min^-1,whichconvertstoaresidencetimehalf-life(t_t1/2)of16±8min.Themeasuredoff-rateforAvibactamsuggeststhatslowdeacylationthroughhydrolysisorreversibilityisoccurring,anditisincontrasttopreviouslyreportedextremelylongt_1/2valuesof>1or>7dforAvibactaminhibitionofTEM-1^[1].Avibactamisanewpromisingβ-lactamaseinhibitor,toovercomeresistancecausedbyβ-lactamases.Miceareinfectedwithca.10⁶CFUofPseudomonasaeruginosaintramuscularlyintothethighorintranasallytocausepneumoniaandaregiven8different(single)subcutaneousdosesofCeftazidimeandAvibactaminvariouscombinedconcentrations,rangingfrom1to128mg/kgofbodyweightin2-foldincreases.Themeanestimatedhalf-lifeinplasmaofCeftazidimeintheterminalphaseis0.28h(SD,0.02h),andthatofAvibactamis0.24h(SD,0.04h).Volumesofdistributionare0.80liters/kg(SD,0.14liters/kg)and1.18liters/kg(SD,0.34liters/kg),respectively^[3].

• [1].EhmannDE,etal.Avibactamisacovalent,reversible,non-β-lactamβ-lactamaseinhibitor.ProcNatlAcadSciUSA.2012Jul17;109(29):11663-8.

  [2].LivermoreDM,etal.Characterizationofβ-lactamaseandporinmutantsofEnterobacteriaceaeselectedwithceftaroline+avibactam(NXL104).JAntimicrobChemother.2012Jun;67(6):1354-8.

  [3].BerkhoutJ,etal.Pharmacokineticsandpenetrationofceftazidimeandavibactamintoepithelialliningfluidinthigh-andlung-infectedmice.AntimicrobAgentsChemother.2015Apr;59(4):2299-304.

Ina200μLreactionvolume,1μMTEM-1isincubatedwithandwithout5μMAvibactamfor5minat37°Candsubjectedtotwoultrafiltrationcartridge(UFC)stepstoremoveexcessinhibitor(Ultrafree-0.5withBiomaxmembrane,5-kDacutoff).Centrifugationat10,600×gfor8minisperformedat4°C.Aftereachultrafiltrationstep,20μLretentatearedilutedwith180μLassaybuffertorestoretheoriginalenzymeconcentration.AftertwoUFCtreatments,theamountoffreeAvibactamisquantifiedbyliquidchromotography/MS/MSandfoundtobe<5% of="" the="" original="" concentration.="" loss="" of="" protein="" during="" ufc="" is="" assessed="" by="" measuring="" tem-1="" activity="" (on="" 4,000-fold="" dilution)="" in="" the="" acyl-enzyme="" sample="" compare="" with="" non-ufc-treated="" enzyme,="" and="" loss="" is="" found="" to="" be=""><>^[1].MCEhasnotindependentlyconfirmedtheaccuracyofthesemethods.Theyareforreferenceonly.

Avibactamispreparedinsterilewater^[2].

Cells(~10⁹cfu)fromovernightbrothculturearespreadonMueller-Hintonagarsupplementedwitheither(i)CeftarolineplusAvibactam(1or4mg/L)at1-16×theMICsor(ii)Ceftarolineat1or4mg/LplusAvibactamat1-8×theconcentrationneededtoreducetheCeftarolineMICto1or4mg/L.Coloniesarecountedafterovernightincubationandrepresentativesareretained^[2].MCEhasnotindependentlyconfirmedtheaccuracyofthesemethods.Theyareforreferenceonly.

Avibactamisreconstitutedinsterilewatertoastocksolutionof5120mg/LandfurthersolutionispreparedinMueller-Hintonbroth(Mice)^[3].

Mice^[3]
Avibactamisreconstitutedinsterilewatertoastocksolutionof5,120mg/LandfurthersolutionispreparedinMueller-Hintonbroth.OutbredfemaleCD-1mice,7to8weeksoldandweighing20to25g,areusedintheexperiments.Eightdosecombinationsareused.Forthethigh-infectedanimals,thecombinationsofCeftazidimeandAvibactamare16/4,8/1,64/32,and2/128mg/kg.Forthelung-infectedmice,combinationsof32/16,4/2,128/8,and1/64mg/kgoftherespectiveconstituentsareused.Thesecombinationsarechoseninordertodetectpossiblepharmacokineticinteractionsbetweenthetwocompounds(CeftazidimeandAvibactam)andtocoverawiderangeofdosesofeachcompound.MCEhasnotindependentlyconfirmedtheaccuracyofthesemethods.Theyareforreferenceonly.

• [1].EhmannDE,etal.Avibactamisacovalent,reversible,non-β-lactamβ-lactamaseinhibitor.ProcNatlAcadSciUSA.2012Jul17;109(29):11663-8.

  [2].LivermoreDM,etal.Characterizationofβ-lactamaseandporinmutantsofEnterobacteriaceaeselectedwithceftaroline+avibactam(NXL104).JAntimicrobChemother.2012Jun;67(6):1354-8.

  [3].BerkhoutJ,etal.Pharmacokineticsandpenetrationofceftazidimeandavibactamintoepithelialliningfluidinthigh-andlung-infectedmice.AntimicrobAgentsChemother.2015Apr;59(4):2299-304.

287.23

C₇H₁₀N₃NaO₆S

1192491-61-4

RoomtemperatureincontinentalUS;mayvaryelsewhere

DMSO:≥30mg/mL

*"<1 mg/ml"="" means="" slightly="" soluble="" or="" insoluble.="" "≥"="" means="" soluble,="" but="" saturation="">