Novel valsartan-loaded solid dispersion with enhanced bioavailability and no crystalline changes.

Area of Science:

• Pharmaceutical Sciences
• Drug Delivery Systems
• Materials Science

Background:

• Valsartan is a poorly water-soluble drug, limiting its oral bioavailability.
• Developing effective drug delivery systems is crucial for improving the therapeutic efficacy of hydrophobic drugs like valsartan.

Purpose of the Study:

• To formulate and characterize a novel valsartan-loaded solid dispersion with enhanced bioavailability.
• To investigate the impact of hydroxypropyl methylcellulose (HPMC) and sodium lauryl sulphate (SLS) ratios on valsartan solubility and release.
• To evaluate the in vivo pharmacokinetic performance of the developed solid dispersion.

Main Methods:

• Preparation of valsartan-loaded solid dispersions using HPMC and SLS.
• Physicochemical characterization via scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and X-ray diffraction (XRD).
• In vivo bioavailability studies in rats comparing the solid dispersion to valsartan powder and a commercial product (Diovan).

Main Results:

• The optimized valsartan/HPMC/SLS solid dispersion (3/1.5/0.75 ratio) exhibited a 43-fold increase in aqueous solubility.
• SEM, DSC, and XRD confirmed the formation of solid dispersions with no crystalline changes in valsartan.
• In vivo studies showed a 2.2-fold and 1.7-fold increase in bioavailability compared to valsartan powder and Diovan, respectively, with improved pharmacokinetic parameters (AUC, Cmax, Tmax).

Conclusions:

• The developed valsartan-loaded solid dispersion effectively enhances drug solubility and bioavailability.
• The formulation strategy avoids crystalline changes, ensuring drug stability.
• This novel solid dispersion presents a promising approach for delivering poorly water-soluble valsartan.