Nanoparticulate Drug Delivery: Ezetimibe and Enteric-coated Atorvastatin in Hard Gelatin Capsules

Abstract

Aims: Atorvastatin (ATV) and ezetimibe (EZT), being BCS class II drugs, are used to treat dyslipidemia. In this
study, the formulation of hard gelatin capsule containing a fixed dose combination of EZT and enteric-coated ATV
enhances the rate of dissolution through solubility using nanoprecipitation method. Materials and Methods: ATV
nanoparticles (NPs) and EZT NPs were prepared using polyvinyl pyrrolidine k-30 as an amorphous carrier in
various drug to polymer ratios. The formulated NPs of both drugs were characterized for their particle size, zeta
potential, and polydispersity index, and for optimized formulation entrapment efficiency and scanning electron
microscopy (SEM) which were determined. AT VNPs were coated using ethyl cellulose and were characterized.
Flow characteristics of enteric-coated ATV and EZT NPs were assessed and filled into empty hard gelatin
capsules. The hard gelatin capsule containing powders of EZT and enteric-coated ATV NPs was also evaluated
for weight variation, disintegration time, in vitro drug release, and drug content. Results and Discussion: The
particle size for the formulation of ATV NP and EZT NP was found to be 470.5 nm and 469.2 nm, respectively.
The morphology of the best formulation for both NPs, determined using SEM, indicates that they are spherical in
shape. The in vitro release studies of enteric-coated ATV NPs show 5% release in an acidic pH for 2 h followed
by 92.89% release in a basic pH at the end of 3 h before loading into hard gelatin capsules to prove that there was
no release of ATV NPs in acidic medium. Hard gelatin capsules containing enteric-coated ATV NPs and EZT NPs
showed drug release of 98% and 99% within 45 min. Conclusion: The hard gelatin capsule of enteric-coated ATV
NPs and EZT NPs showed better drug release when compared to the marketed formulation.