PAH activator
Phenylalanine hydroxylase (PAH) activator
- Supplies tetrahydrobiopterin (BH4), the cofactor phenylalanine hydroxylase requires
- Restores residual PAH activity in responsive phenylketonuria → ↓ blood phenylalanine
- Response depends on residual enzyme — null PAH variants do not respond
Drugs with this mechanism (2)
- Sepiapterin — BH4 precursor for phenylketonuria; restores cofactor needed by phenylalanine hydroxylase.
- Tetrahydrobiopterin — Cofactor for phenylalanine hydroxylase; sapropterin and sepiapterin restore it.
Self-check
- Why do null PAH variants fail to respond to PAH activation?
Response requires residual enzyme activity. - Which cofactor is supplied to activate PAH?
Tetrahydrobiopterin (BH4).
All mechanisms · Open PAH activator in the interactive console ↗