Chewing gum containing repaglinide solid dispersion using mesoporous silica nanoparticles for management of diabetes mellitus: In-vitro evaluation and clinical appraisal

The current study aimed to formulate repaglinide solid dispersion via mesoporous silica nanoparticles (R-MSNs) as a carrier in an attempt to enhance drug solubility. Then incorporation of it in a medicated chewing gum (MCG); to enhance the drug bioavailability, for the treatment of diabetes mellitus. R-MSNs solid dispersion formulations (R-MSNs-SD) were prepared using the solvent evaporation method. The chosen formula was investigated in terms of FTIR, DSC, and XRD in addition to morphology that was studied by SEM. The results demonstrated that repaglinide was successfully loaded into the pores of MSNs. The cytotoxicity of the chosen formula was evaluated by SRB assay using a Vero cell line and the cytotoxic effect of repaglinide was found to be diminished when incorporated within MSNs. Subsequently, MCGs were formulated using the chosen R-MSNs-SD as well as pure repaglinide and tested for physical properties, content uniformity, and drug release. The results exhibited a notable improvement in the release of repaglinide from the MCG containing pure repaglinide and R-MSNs-SD. A clinical investigation was further conducted on diabetic patients for MCGs containing R-MSNs-SD or pure repaglinide and compared to the marketed product where the blood glucose level was measured. MCG formulations specially the one loaded with R-MSNs-SD showed enhanced antidiabetic activity than the marketed product suggesting a promising oral antidiabetic delivery system for repaglinide.