Introduction: Ursodeoxycholic acid (UDCA) is used to treat liver and biliary disorders, including neonatal jaundice. In neonatal practice, UDCA administered orally (10–30 mg/kg/day, divided doses) shortens phototherapy duration and reduces serum total bilirubin. A suspension dosage form may mask bitter taste, improve dissolution and bioavailability, and is not currently registered in Mongolia. To develop and evaluate suspension formulations of UDCA and to identify an optimal composition and manufacturing technology. Methods: UDCA drug substance was characterized according to the European Pharmacopoeia (EP 11.0). Five suspension formulations (A1–A5) were prepared using wet-milling (size-reduction) technology and appropriate excipients. Physical, chemical and microbiological quality attributes of the suspensions were assessed per the United States Pharmacopeia (USP 2021) and microbiological methods of the Pharmacopoeia of the Russian Federation (GOST 2018). Assays were performed by validated chromatographic methods; measurements were performed in triplicate (n=3).
The UDCA raw material met pharmacopeial specifications and was suitable for use. All five formulations were uniform and free of agglomerates by visual inspection. Formulation A5 met USP acceptance criteria for pH (4.5 ± 0.02), sedimentation volume (0.91 ± 0.20 mL), density (1.14 ± 0.005 g/cm3), viscosity (1583.5 ± 0.38 mPa·s), fill volume (150 ± 0 mL) and active substance content (96.6 ± 0.05%), and complied with microbiological limits. Other formulations failed one or more quality attributes (notably pH, assay or sedimentation). Conclusion The UDCA raw material complied with pharmacopeial quality standards. Among tested variants, formulation A5 satisfied critical quality attributes for a stable suspension and was identified as the optimal formulation with respect to composition and manufacturing process.