Abstract
Abstract
Azilsartan medoxomil is a prodrug of the active metabolite, Azilsartan, which is angiotensin II receptor blocker that is used to treat hypertension. Azisartan medoxomil is classified as class II according to biopharmaceutical classification, so the drug has a problem in low solubility and dissolution rate and therefore low bioavailability and therapeutics effect. Solid dispersion is one of the most effective techniques that enhance dissolution rate of the drug by entrapping and dispersing it inside a hydrophilic carrier. The aim of this present study was to improve dissolution rate of the Azilsartan medoxomil by preparing it as solid dispersion using PEG 6000 as a polymer carrier in different ratio of drug to polymer (1:2, 1:3, 1:4, 1:5) using solvent evaporation method . The formulation then were evaluated as their production yield ,in vitro drug release, and % of crystallinity was measured for pure drug and the best formula using differential scanning calorimetry (DSC) analysis. The formulas prepared by solid dispersion techniques have good production yield and higher dissolution rate in addition to very reduction in the % of crystallinity for the selected formula in comparing with pure drug. The finding results of the best formula which is F4 that prepared by solvent evaporation method and PEG 6000 carrier at 1:5 drug to polymer ratio reveal the conversion of Azilsartan medoxomil from crystal to more soluble amorphous form which is confirmed by the DSC data and by measuring the % of crystallinity. We conclude from this study, the solvent evaporation method is an efficient method to prepare Azilsartan medoxomil solid dispersion and it is cost effective, easy to formulate with highly improvement in the drug solubility and dissolution rate, also we can calculate % of crystallinity by using DSC results.
Keywords: Azilsartan medoxomil, solid dispersion, % crystallinity, DSC.
