Paediatric formulation: budesonide 0.1 mg/mL viscous oral solution for eosinophilic esophagitis using cyclodextrins

Abstract Background Viscous oral solutions of budesonide (dose range: 1 mg to 2 mg) have long been used to treat eosinophilic oesophagitis in children. The objective of the present study was to provide a convenient paediatric pharmaceutical formulation of a viscous budesonide solution at a dose level of 0.1 mg/mL, using cyclodextrin as a solubilizer. Methods Solubility studies were performed with γ-cyclodextrin and hydroxypropyl-β-cyclodextrin, and viscosity was tested with a Brookfield viscometer. The stability of the final formulation was tested in a climatic chamber. Levels of budesonide, budesonide impurities and degradation products were assayed using the HPLC–UV method described for the budesonide-related substance assay in the European Pharmacopoeia monograph. Results The solubility of budesonide increased linearly with both cyclodextrins. Gamma cyclodextrin (complexation efficiency: 0.147) was preferred to hydroxypropyl-β-cyclodextrin (complexation efficiency: 0.064) as a solubilizing agent. Hydroxypropylcellulose (1 % m/v) was added to increase viscosity, and sucralose was added to improve palatability. The sterilized, filtered, final formulation was stable for at least 3 months when packed aseptically in sterile 15 mL type 1 amber glass vials. Conclusions We have developed a convenient, stable, preservative-free, viscous formulation of a budesonide solution for the hospital- and home-based treatment of paediatric patients.