CsA Delivery via Nanoparticles

Different micelle formulations based upon the amphiphilic polymer poly(ethylenimine), PEI, loaded with cyclosporine A and formed into tablets were tested for comparative drug absorption against CsA-in-water and CsA-microemulsion in a rat model by Le and colleagues [34]. Various PEI-CsA nanoparticles were examined, which differed based on linear or branched formations of the polymer. They determined that polymer hydrophobicity was the primary determinant to enhance CsA encapsulation and oral CsA absorption (bioavailabihty), and not polymer molecular weight or polymer branching. Polymers need at least 10% of their monomers to exhibit hydrophobicity in order to encapsulate sufficient drug and enable oral absorption enhancement. In this study, only the most hydrophobic PEI-CsA nanoparticles produced significantly enhanced CsA absorption compared to CsA-in-water, but none were superior to CsA-ME. 

In conclusion, multiple platforms are now available for targeted deUvery of immunosuppressive drugs for either activation of a specific subset of immime cells or for other pharmaceutical reasons. The use of polymers to achieve these disparate goals is by now quite extensive. 

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