Orodispersible tablets of telmisartan through cyclodextrin-surfactant complexation: A quality by design approach

Telmisartan is a poorly water-soluble drug with dissolution limited bioavailability. In this work, solubility and dissolution rate were aimed to improve through the development of cyclodextrin (CD) complexes containing surfactant; followed by developing them into orodispersible tablets (ODTs). Quality by design approach was adopted in the optimization of CD-surfactant complex as well as in the optimization of ODTs. Type of cyclodextrins, the concentration of the cyclodextrins, and concentration of poloxamer 188 were taken as the factors in the preparation of inclusion complexes by solvent evaporation method. Solubility was taken as the response variable. The optimized formulation of the complex was taken for ODTs preparation. Concentration of povidone, concentration of super-disintegrant and type of super-disintegrant were taken as the independent factors, and disintegration time (DT) and time for 90% dissolution (T90%) were taken as the responses. The tablets were prepared by direct compression technique. The results of both the responses were analyzed by response surface quadratic model for the influence of the factors on them. All three factors were found to have significant influence on both the responses (at p < 0.05). Graphical optimization was performed by desirability functions approach in order to have low DT and low T90%. The optimized telmisartan CD-surfactant complex was found to have a solubility of 2.86 mg/mL. The optimized ODTs were found to have 20.4 sec. DT and 7.3 min. T90%. These results indicated that enhancement of solubility of telmisartan as well as dissolution of the ODTs was successfully improved through quality by design approach.