Formulation and in vivo hypoglycemic effect of glipizide solid dispersion

Area of Science:

• Pharmaceutical Sciences
• Drug Delivery Systems
• Materials Science

Background:

• Glipizide (GZ), a BCS class II drug, exhibits poor water solubility, limiting its therapeutic efficacy.
• Enhancing the dissolution rate of poorly soluble drugs is crucial for improving bioavailability.
• Solid dispersion (SD) technology offers a promising approach to overcome solubility challenges.

Purpose of the Study:

• To enhance the dissolution rate and bioavailability of glipizide (GZ).
• To investigate the efficacy of polyethylene glycol (PEG) 6000, PEG 8000, and poloxamer (PXM) 188 as carriers for glipizide solid dispersions.
• To evaluate the in vivo hypoglycemic effect of the optimized glipizide solid dispersion.

Main Methods:

• Solid dispersions (SDs) were prepared using the melting method with varying glipizide-to-carrier ratios.
• Phase solubility studies were conducted to assess carrier impact on glipizide solubility.
• Optimization involved drug content estimation and in vitro dissolution studies.
• Characterization included SEM, FTIR, DSC, and XRD analyses.
• Preclinical efficacy was assessed via blood glucose level reduction in mice.

Main Results:

• Poloxamer 188 (PXM 188) at a 1:2 weight ratio demonstrated superior solubility and drug release.
• Optimized SD formulations showed significantly enhanced in vitro dissolution profiles.
• Characterization studies confirmed the successful formation of solid dispersions.
• In vivo studies revealed a significant (p < 0.05) reduction in blood glucose levels compared to pure glipizide.

Conclusions:

• Solid dispersion technology effectively enhances the dissolution rate of poorly water-soluble glipizide.
• Poloxamer 188 is a suitable carrier for developing glipizide solid dispersions with improved pharmacokinetic properties.
• The developed solid dispersion formulation holds potential for improved therapeutic outcomes in managing diabetes.