INVESTIGATION OF SOLID DISPERSION APPROACH FOR THE IMPROVEMENT OF PHARMACEUTICAL CHARACTERISTICS OF TELMISARTAN USING A CENTRAL COMPOSITE DESIGN

Abstract

Objective: The goal of this study was to use a solid dispersion approach to improve the aqueous solubility and dissolution rate of Telmisartan. Methods: Design of experiment trials was conducted following a central composite design with different combinations of polymers and stirrer rpm and the selected responses (drug release, entrapment efficiency) were determined. The selected optimized formulation was characterized by Fourier-transform infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy, and X-ray diffraction, which reflected the changes that occurred in API and excipients after conversion in to the formulation. Results: In the design of experiments, central composite design was implemented and it was observed that polymers concentration (polyvinyl pyrrolidine K25, polyethylene glycol 4000) and stirrer rpm were having a significant impact on the responses (drug release, entrapment efficiency), and variables were having p-value<0.05 which reflected the significant impact. The results of stability study showed a significant no decrease in drug assay values, which reflected the stability behavior of the formulation. The results of comparative dissolution studies revealed that the optimized formulation have improved the drug solubility and dissolution rate. Conclusion: It can be concluded that optimized telmisartan-loaded solid dispersion improved the solubility and dissolution rate of Telmisartan. The optimized formulation was having release>85% release within 30 min. Further, the stability of the formulation was also assessed under the accelerated condition as per ICH which reflected their stability. So, this approach can be employed for improving dissolution rate of other BCS II class drugs.