Physicochemical characteristics and in vitro release from oil-based vehicles of peptidomimetics: parenteral depots for intra-articular administration

Abstract

Results: Basic physicochemical properties including their apparent solubility in aqueous buffer and vegetable oils of a series of 11 peptidomimetics varying with respect to chain length and degree of N-methylation were estimated. It was observed that the compounds in contact with water transformed into sticky, slowly dissolving semisolid materials. Based on these observations, the in vitro release behavior of selected peptide derivatives from oil solutions and in situ formed precipitates was investigated using a validated in vitro release model. Conclusion: The results of this investigation suggest that both types of oil-based drug delivery systems might constitute alternative sustained release formulation principles of such amorphous peptide derivatives for the intra-articular route of administration.

• Depot formulation
• in situ forming DDS
• intra-articular drug delivery
• oil solution
• semisolid precipitates

Acknowledgments

The present study was supported by Novo Nordisk A/S via the Drug Research Academy, Faculty of Pharmaceutical Sciences, University of Copenhagen, Denmark, The Danish Medical Research Council, and the Danish Rheumatism Association. The technical assistance of Peter Andersen (Novo Nordisk A/S) during synthesis of the peptidomimetics is highly valued.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this paper.