U.S.researchershaveidentifiedanewwaytotreatpeopleinfectedwithtuberculosisbeforetheygetsick.Thecombinationdrugregimen,endorsedbytheU.S.CentersforDiseaseControlandPrevention(CDC),wouldsimplifytreatment,cuttingitfrom9monthsto3months.Tuberculosisisoneoftheworldmostpersistenthealththreat.Now,U.S.researchershaveidentifiedanewwaytotreatinfectedpeoplebeforetheygetsick.TheWorldHealthOrganizationsaystuberculosiskillsnearlytwomillionpeopleeachyear.Anothertwobillionareatrisk:theyareinfected,butdon'thavesymptomsofthedisease.Thoseathighestriskcantakemedicine,butVanderbiltUniversityresearcherTimothyStirlingsaysnoteveryonefollowsthroughwiththetreatment,whichisadailydoseofisoniazidforninemonths."Soalthoughthemedicationishighlyefficaciousifpeopletakealloftheirmedication,manypeopledonottakealltheirmedicationandthereforetheeffectivenessoftheregimenisdecreased."Asanalternative,Sterlingandhiscolleaguescombinedisoniazidwithanotherdrug,rifapentine.Thecombinationwastakenweeklyforjustthreemonths."Andtheresultsofthisstudyshowedthatthenewregimen-thethreemonthsofisoniazidandrifapentine-wasaseffectiveasthenine-monthisoniazidregimen,"Sterlingsays."Andinfact,theshort-course,three-monthregimenhadhighertreatmentcompletionratesandwasalsowelltolerated."Therewasoneotherdifference.Thetwo-drug,combinationtreatmentwasadministeredas"directlyobservedtherapy."Thatmeansthepatientstooktheirmedicineinthepresenceofahealthcareworker,toensurethattheyfollowedthetreatmentprotocol.Thiswasalargestudy,involvingsome7,500participantsinNorthAmerica,Spain,andBrazil.SterlingcautionsthatmostofthepeopleinthisstudywereHIV-negative.TheresultsmightbedifferentforHIV-positivepeople.ArecentstudyinSouthAfricaindicatedthatthecombinationtherapyworkswellinpeopleinfectedwithHIVaswellastuberculosis,butthestudywastoosmalltobedefinitive.TimothySterling'sresearch,in"TheNewEnglandJournalofMedicine,"hasbeenendorsedbytheU.S.CentersforDiseaseControlandPrevention,theCDC.Thegovernmenthealthagencyrecommendsthe12-doseweeklycombinationtreatmentasanequalalternativetothe270-dosedailyregimenthathasbeenthestandardtherapy.Butbecauseofpossiblesafetyissues,theCDCstillrecommendsthedailyregimenforHIV-positivepatientswhoaretakingantiretroviraldrugsorwomenwhoarepregnant.Also,becauseofalackofdata,theCDCsayschildrenunderage12shouldstaywiththenine-monthdailytreatment.
