Expert: Small-molecule pharmacological chaperone that binds and stabilizes mutant phenylalanine hydroxylase (PAH) enzyme, restoring catalytic activity for phenylalanine-to-tyrosine conversion. Mechanism distinct from BH4 cofactor supplementation (sapropterin).

Everyday: Stabilizes the misfolded enzyme (PAH) that PKU patients are born with. Like straightening out a bent key so it can fit the lock again — the enzyme works better, breaking down phenylalanine so it does not build up to toxic levels.

Targets: []

Repinatrabit - PKU - Ph3 - Topline (NCT06971731) Early 2027

Phase 3 initiated Dec 2025. Developed by Jnana Therapeutics (Otsuka subsidiary). Orphan drug + rare pediatric disease designation.