Stability study of a thalidomide suspension

Background: Thalidomide is being used increasingly for its immunomodulatory, anti-inflammatory and anti-angiogenic properties. Data on the stability of an oral liquid thalidomide formulation for use in patients with swallowing difficulties and enteral feeding tubes are lacking. Aim: To determine the stability of a thalidomide 100 mg/10 mL suspension. Method: Thalidomide 100 mg/10 mL suspension was formulated (in triplicate) using Thalomid capsules and stored at room temperature (22 ± 1 °C) for 31 days. Stability was assessed via high-performance liquid chromatography (HPLC) on Days 7, 14, 21 and 31. Assay suitability was analysed via forced degradation products of thalidomide samples under acidic, basic and oxidative conditions. Results: A validated thalidomide HPLC assay indicated that the original thalidomide content of the suspension remained within 5% throughout the 31-day study period. After shaking, no visible changes in suspension consistency, colour or sedimentation were observed. Conclusion: The formulated thalidomide 100 mg/10 mL suspension when protected from light and stored at room temperature was stable for up to 31 days.