Development of a novel intramuscular liposomal injection for advanced meloxicam delivery: Preparation, characterization, in vivo pharmacokinetics, pharmacodynamics, and pain assessment in an orthopedic pain model.

Pain produces several physiological, and degenerative complications. This study aimed to formulate meloxicam (MLX) in liposomes to increase solubility and deliver MLX in a controlled manner to overcome its poor aqueous solubility and relatively short t _1/2 problems. Liposomes were prepared by thin film hydration followed by ultrasonication. Tests for characterizing formulations included particle size, span, entrapment efficiency, drug loading, stability, differential scanning calorimetry (DSC), Fourier transformation infrared (FT-IR) spectroscopy, morphology, in vitro release, release kinetics mathematical modeling, and an in vivo pain model in dogs undergoing orthopedic surgeries, followed by in vivo pharmacokinetics, pharmacodynamics, and pain assessment studies in comparison to the reference standard, Mobitil®. Liposomal MLX had a particle size of around 100 nm, 82 % entrapment efficiency, and 4.62 % drug loading. Stability studies, DSC, and FT-IR spectroscopy indicated that liposomes were highly stable. The formulation showed an improved in vitro controlled release pattern and an enhanced in vivo pharmacokinetic behavior as manifested by higher t _1/2 and AUC _{0 - 24} and lower Cl/F in comparison to Mobitil®. The pharmacodynamics study and pain scales demonstrated liposomal MLX managed postoperative pain better than Mobitil®. In conclusion, the incorporation of MLX in liposomes increased its solubility and stability, as well as its pain management properties.
Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(© 2024 The Authors. Published by Elsevier B.V.)