Polymeric Precipitation Inhibitor Assisted Supersaturable SMEDDS of Efavirenz Based on Experimental Observations and Molecular Mechanics.

Abstract

Supersaturable SMEDDS, a versatile dosage form, was investigated for improving the biopharmaceutical attributes and eradicating the food effect of poorly water soluble drug efavirenz. The present research pursues the development of efavirenz loaded Supersaturable Self- Microemulsifying Drug Delivery System (SS SMEDDS) for improving biopharmaceutical performance. Preformulation studies were carried out to determine the optimized range of lipid excipients to develop stable supersaturated SMEDDS (ST SMEDDS). The SS SMEDD formulation was prepared by adding hydroxypropyl methylcellulose as a polymeric precipitation inhibitor. The developed SS SMEDDS were evaluated for supersaturation behavior by performing in vitro supersaturation studies and molecular simulations by in silico docking. Dissolution was performed in biorelevant media to simulate fed/fasted conditions in gastrointestinal regions. Absorption behavior was determined through in vivo pharmacokinetics approach. The optimized ST SMEDDS formulation containing Maisine® CC, Tween 80 and Transcutol-P exhibited thermodynamic stability with quick rate of emulsification. The optimized SS SMEDDS containing suitable polymeric precipitation inhibitor exhibited enhanced efavirenz concentration in in vitro supersaturation test. The theoretical simulations by molecular docking revealed strong intermolecular interactions with a docking score of -3.004 KJ/mol. The dissolution performance of marketed product in biorelevant dissolution media inferred the existence of food effect in the dissolution of efavirenz. However, in SS SMEDDS, no significant differences in drug release behavior under different fasted/fed conditions signify that the food effect was neutralized. In vivo pharmacokinetics revealed a significant increase in the absorption profile of efavirenz from SS SMEDDS than that of ST SMEDDS and marketed product. The designed delivery system indicated promising results in developing an effectual EFV formulation for HIV treatment.