New sickle cell treatment ready for testing

时间 : 2009-12-03 02:33:59 来源：www.scidev.net

[摘要]

L-glutamineplumpsupsickle-shapedbloodcellsandpreventsbloodvesselblockage,saytheresearchers

USNationalHumanGenomeResearchInstitute

AtreatmentthatreducesthenumberofbloodcellsdeformedbysicklecellanaemiahaspassedearlytestsinpeopleandwillsoonbeginphaseIIIclinicaltrials.

Thetrials,whichwilllookatsafetyandefficacyinalargenumberofpeople,wereapprovedinAprilbytheUSFoodandDrugAdministration（FDA）andshouldbegininSeptember.

Sicklecellanaemiaisahereditaryblooddisorderforwhichthereisnoknowncure.Theexperimentaltreatmentisapillformofthenaturally-occurringaminoacidL-glutamine,whichplumpsupredbloodcellsdeformedbythediseasemakingthemlesslikelytoblocksmallbloodvesselsandcausedebilitatingpain,saysYutakaNiihara,principalinvestigatorattheLosAngelesBiomedicalResearchInstitute（LABioMed）,wherethetreatmentisbeingdeveloped.

"InourphaseIIclinicaltrialweobservedanexcellentsafetyprofileandpositivetrendsinreducingthenumberofcrisesandhospitalisationsinsicklecelldiseasepatients,"saidNiiharainapressrelease.

FewothertreatmentsforthisdisorderhaveprogressedtoPhaseIII.

Butthepriceofthedrugislikelytobeanissueindevelopingcountrieswheremedicationismostneeded.ThecostofusingL-glutaminetotreatanotherdisease—shortbowelsyndrome—isaroundUS$600permonthperpatientandNiiharaexpectsinitialcoststobesimilarforsicklecellanaemia.

ButheiskeenforL-glutaminetobemadeaffordableindevelopingcountries—particularlyinAfricawherethediseaseismostprevalent.

"ForAfricawewouldliketoplansomethingviaanon-profitorganisationsoitwillbemoreeasilyavailabletopeoplewithoutresources,"NiiharatoldSciDev.Net.L-glutamineisalreadysoldcommerciallyinmanypharmaciesinthedevelopedworldanditisoftensoldasasportssupplement.IntheLABioMedtrials,however,patientsarebeinggivenamoreconcentrated,pharmaceutical–leveldoseoftheaminoacid.

JosephOjobi,aconsultantattheJosUniversityTeachingHospitalinNigeria,saystheresearchsuggeststhatsicklecellpatientswhoswitchtoaprotein-richdietmightalsobeabletoalleviatesomeoftheirsymptomsasproteinisagoodsourceofL-glutamine.

Buthewarnsthatdietarychangescannotalterthemutatedgenethatcausessicklecellanaemiaandmightnotalleviateallthesymptoms.