Multicomponent solid dispersion as a formulation strategy to improve drug permeation

Multicomponent solid dispersions (MSD)s are frequently proposed as efficient drug delivery systems to improve drug solubility and bioavailability. In this study, the effects of specific excipients, such as mannitol, inulin, poly(methyl methacrylate-co-methacrylic)acid (PMMA) and cellulose acetate phthalate (CAP) have been tested to potentially improve irinotecan (IRN) permeation in the intestinal tract with the intention to protect the drug from the gastric environment.

MSDs were formulated as microparticles by Spray-Drying technique. Raw materials and microparticles have been characterized by FTIR analysis to determine hydrogen bonding. SEM images were recorded to investigate morphology and particle size of drug-loaded microparticles, and thermal analysis was used to confirm that drug physical morphology was maintained during formulation.

Finally, in vitro dissolution studies and ex-vivo experiments across colon sections were carried out. The drug-loaded microparticles resulted to have an average particle size of below 6 μm and increased both drug dissolution rate and permeation through the intestine. The use of specific excipients improved properties such as drug dissolution performances and drug absorption through the intestinal barrier. The selected method and excipients increased IRN dissolution rate in all the formulations prepared. Finally, ex-vivo experiments across colon sections demonstrated an increase of drug permeation through MSDs respect pure IRN. More on multicomponent solid dispersions