In vitro and in vivo evaluation of a self-microemulsifying drug delivery system for the poorly soluble drug fenofibrate

Fenofibrate is indicated in hypercholesterolemia and hypertriglyceridemia alone or combined (types IIa, IIb, III, IV, and V dyslipidemias). However, due to its low solubility in water, it has low bioavailability after oral administration. In order to improve the dissolution rate, fenofibrate was formulated into a self-microemulsifying drug delivery system (SMEDDS). We used pseudoternary phase diagrams to evaluate the area of microemulsification, and an in vitro dissolution test was used to investigate the dissolution rate of fenofibrate. The optimized formulation for in vitro dissolution and bioavailability assessment consisted of propylene glycol laurate (Lauroglycol FCC) (60 %), macrogol-15-hydroxystearate (Solutol HS 15) (27 %), and diethylene glycol monoethyl ether (Transcutol-P) (13 %). The mean droplet size of the oil phase in the microemulsion formed by the SMEDDS was 131.1 nm. The dissolution rate of fenofibrate from SMEDDS was significantly higher than that of the reference tablet. In vivo pharmacokinetics study of fenofibrate in beagles administered SMEDDS-A form resulted in a 3.7-fold increase in bioavailability as compared with the reference drug. Our studies suggested that the fenofibrate containing SMEDDS composition can effectively increase the solubility and oral bioavailability of poorly water-soluble drugs.