Improving Solubility of the Telmisartan that is Poorly Water Soluble by Wet Granulation and Vitrification Process

Telmisartan (TS) have developed for the treatment of hypertension as the angiotensin II receptor blocker. TS belongs to class II drug in BCS classification and it has good permeability. But, it is poorly water soluble. Biological half-life of TS is 24 hours because it has not good bioavailability (only 42 similar to 58%). The absorption of a drug is often limited by dissolution rate. Drug dissolution is important factor to the therapeutic efficacy of a medicine. Therefore, TS requires alternative methods of drug delivery system to improve solubilization. In this study, we have prepared solid dispersions (SD) of the TS, polyvinylpyrrolidone (PVP) K-30 using rotary evaporation to promote release rate. So, we made sustained release formulation to make that is continually released and reduced the number of administration to patients. We selected the methods which are wet granulation (WG) and vitrification (VT) for sustained release. WG is a common techinique in the pharmaceutical industry that is mixing the powder to make bonds between powder particles using water. VT is techinique that transforms the crystalline particle into amorphous state using cryomilling. We measured the characterization of SD that was performed using various methods to analyze the structure of powder sample. Characterizations of SD were performed to analyze the surface by scanning electron microscopy. The crystallinity and molecular structure are analyzed by Fourier transform infrared spectroscopy, powder X-ray diffractometer. Also, thermal porperties are analyzed by differential scanning calorimeter. In vitro dissolution test assessed by RP-HPLC to analyze dissolution rate of sustained release formulation and solid dispersion. In this results, these indicate that both methods improve solubility and dissolution rate. The drug solubility of processed VT almost greater than the pure drug and WG. And, in Bats, VT 3 has higher dissolution rates than others. So, this results are useful to improve TS in the pharmaceutical industry.