{"id":"tetrahydrobiopterin","rwe":[],"tags":[],"phase":"discontinued","safety":{"boxedWarnings":[],"safetySignals":[],"drugInteractions":[],"commonSideEffects":[],"contraindications":["Neutropenic disorder"],"specialPopulations":{},"discontinuationRates":[],"seriousAdverseEvents":[]},"status":"discontinued","trials":["NCT00943579","NCT00964236","NCT00104260","NCT04800692","NCT00919295","NCT03493412","NCT00332189","NCT01425528","NCT06987773","NCT00827762","NCT00484991","NCT01398943","NCT06312748","NCT03841383","NCT01376908","NCT00728676","NCT00778206","NCT01772758","NCT01439555","NCT02012582","NCT01395394","NCT05847361","NCT00850070","NCT01617070","NCT02042196","NCT00445978","NCT01732471","NCT00027157","NCT00355264","NCT00104247","NCT00789568","NCT01274026","NCT00986973","NCT04227080","NCT05114226","NCT00532844","NCT03136029","NCT01356966","NCT02992236","NCT00325962","NCT05138887","NCT05434195","NCT00272792","NCT01016392","NCT01114737","NCT00225615","NCT01141595","NCT00935753","NCT03680573","NCT00432822"],"aliases":["Kuvan","Sapropterin"],"patents":[],"pricing":[],"offLabel":[],"timeline":[],"aiSummary":"Tetrahydrobiopterin (BH4) is a small molecule cofactor involved in the metabolism of amino acid phenylalanine and the biosynthesis of various neurotransmitters. 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Worcester","competitors":[],"dataSources":[{"url":"https://clinicaltrials.gov","name":"ClinicalTrials.gov","fields":["trialDetails","trials"],"retrievedDate":"2026-04-07"},{"url":"https://drugcentral.org","name":"DrugCentral","fields":["indications","contraindications","safety","target","drugInteractions"],"retrievedDate":"2026-04-07"}],"genericName":"Tetrahydrobiopterin","indications":{"approved":[{"name":"Classical phenylketonuria","diseaseId":"classical-phenylketonuria","approvalDate":"","lineOfTherapy":"","approvalCountry":"United States"},{"name":"Tetrahydrobiopterin deficiency","diseaseId":"tetrahydrobiopterin-deficiency","approvalDate":"","lineOfTherapy":"","approvalCountry":"United States"}],"offLabel":[],"pipeline":[]},"labelChanges":[],"relatedDrugs":[],"trialDetails":[{"nctId":"NCT00943579","phase":"Phase 2","title":"Kuvan® (Sapropterin) as a Treatment for Autistic Disorder: An Open Label Extension Protocol","status":"COMPLETED","sponsor":"The Children's Health 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California","isPivotal":false,"enrollment":10,"indication":"Phenylketonuria (PKU)","completionDate":"2014-12"},{"nctId":"NCT02042196","phase":"EARLY/Phase 1","title":"Biological Mechanisms of Vascular Dysfunction With Age and Estrogen Deficiency","status":"COMPLETED","sponsor":"University of Colorado, Denver","isPivotal":false,"enrollment":100,"indication":"Menopause, Aging","completionDate":"2016-05-02"},{"nctId":"NCT00445978","phase":"Phase 2","title":"A Phase 2a, Multicenter, Open-label, Dose-escalation Study to Evaluate the Safety, Tolerability, and Efficacy of 6R-BH4 in Subjects With Sickle Cell Disease","status":"COMPLETED","sponsor":"BioMarin Pharmaceutical","isPivotal":false,"enrollment":32,"indication":"Sickle Cell Disease","completionDate":"2009-06"},{"nctId":"NCT01732471","phase":"Phase 3","title":"A Phase III Non-comparative Open-label Clinical Study to Evaluate the Response to and Safety of Kuvan (Sapropterin Dihydrochloride) After 6 Weeks of Treatment in Patients of 4 to 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