Urea cycle disorders are a group of inherited orphan diseases leading to hyperammonemia. Current therapeutic strategy includes high doses of sodium benzoate leading to three or four oral intakes per day. As this drug is currently available in capsules or in solution, children are either unable to swallow the capsule or reluctant to take the drug due to its strong bitter taste. The objective of the present study was to develop solid, multiparticulate formulations of sodium benzoate, which are suitable for pediatric patients (i.e. flavor-masked, easy to swallow and with a dosing system). Drug layering and coating in a fluidized bed were applied for preparing sustained-release granules. Two types of inert cores (GalenIQ® and Suglets®) and three different polymers (Kollicoat®, Aquacoat® and Eudragit®) were tested in order to select the most appropriate polymer and starter core for our purpose. Physical characteristics and drug release profiles of the pellets were evaluated. A Suglets® core associated with a Kollicoat® coating seems to be the best combination for an extended release of sodium benzoate. A curing period of 8 h was necessary to complete film formation and the resulting drug release pattern was found to be dependent of the acidity of the release medium.
Keywords: Coated pellets; drug layering; pediatric dosage form; sodium benzoate; sustained release.