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saproterin dihydrochloride

University Hospitals Cleveland Medical Center · FDA-approved active Small molecule

Saproterin dihydrochloride is a synthetic form of tetrahydrofolate that acts as a cofactor to enhance phenylalanine ammonia-lyase (PAL) enzyme activity, reducing blood phenylalanine levels in phenylketonuria.

Saproterin dihydrochloride is a synthetic form of tetrahydrofolate that acts as a cofactor to enhance phenylalanine ammonia-lyase (PAL) enzyme activity, reducing blood phenylalanine levels in phenylketonuria. Used for Phenylketonuria (PKU) in patients with residual phenylalanine ammonia-lyase activity.

At a glance

Generic namesaproterin dihydrochloride
Also known asKuvan treatment
SponsorUniversity Hospitals Cleveland Medical Center
Drug classCofactor replacement therapy
TargetPhenylalanine ammonia-lyase (PAL) cofactor
ModalitySmall molecule
Therapeutic areaMetabolic/Genetic Disorder
PhaseFDA-approved

Mechanism of action

Saproterin (also known as BH4 or tetrahydrobiopterin) is an essential cofactor for the enzyme phenylalanine ammonia-lyase, which catalyzes the conversion of phenylalanine to tyrosine. In phenylketonuria (PKU), patients have deficient or dysfunctional PAL enzyme; saproterin supplementation can restore or enhance residual enzyme activity, thereby lowering toxic phenylalanine accumulation. This mechanism is distinct from dietary phenylalanine restriction and allows some PKU patients to achieve better metabolic control and dietary flexibility.

Approved indications

Common side effects

Key clinical trials

Primary sources

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

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