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Kuvan®

Merck KGaA, Darmstadt, Germany · FDA-approved active Small molecule

Kuvan is a synthetic form of tetrahydrofolate (BH4) that acts as a cofactor to restore phenylalanine ammonia-lyase (PAL) enzyme activity, enabling the metabolism of phenylalanine in patients with phenylketonuria.

Kuvan is a synthetic form of tetrahydrofolate (BH4) that acts as a cofactor to restore phenylalanine ammonia-lyase (PAL) enzyme activity, enabling the metabolism of phenylalanine in patients with phenylketonuria. Used for Phenylketonuria (PKU) in patients with BH4-responsive mutations.

At a glance

Generic nameKuvan®
Also known asSapropterin dihydrochloride, sapropterin, tetrahydrobiopterin, Diagnostic Tests, sapropterin dihydrochloride
SponsorMerck KGaA, Darmstadt, Germany
Drug classCofactor replacement therapy
TargetPhenylalanine ammonia-lyase (PAL) enzyme cofactor
ModalitySmall molecule
Therapeutic areaMetabolic/Genetic Disorders
PhaseFDA-approved

Mechanism of action

Kuvan (sapropterin dihydrochloride) is a pteridine compound that serves as a cofactor for the enzyme phenylalanine ammonia-lyase (PAL), which catalyzes the conversion of phenylalanine to tyrosine. In phenylketonuria (PKU), mutations in the PAH gene reduce PAL enzyme activity, leading to toxic accumulation of phenylalanine. By supplementing with synthetic BH4, Kuvan restores sufficient enzyme cofactor levels in responsive patients, allowing phenylalanine metabolism and reducing blood phenylalanine concentrations.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results