Valiloxybate

Valiloxybate is an extended-release prodrug of γ-hydroxybutyrate which is under development for the treatment of narcolepsy. It is also being investigated for treatment of excessive daytime sleepiness in people with Parkinson's disease. The drug is taken orally once per night.

Pharmacology

It is an amino acid ester prodrug of GHB, which itself acts as a GABA_B and GHB receptor agonist. Relative to administration of GHB itself, valiloxybate showed a delayed time to peak levels and an extended duration of GHB exposure in humans. It is said to maintain desired GHB levels for 6 to 7hours. This profile is compatible with once-nightly dosing, in contrast to GHB itself which is typically administered twice per night due to its very short elimination half-life. In addition, unlike sodium oxybate, valiloxybate contains no sodium or cation, and hence avoids excessive sodium intake.

History

Valiloxybate is under development by XW labs or XWPharma. As of September 2025, no recent development has been reported, but valiloxybate has reached phase 1 clinical trials for treatment of narcolepsy and phase 2 trials for treatment of sleeping problems in Parkinson's disease.