OPTIMIZATION OF TELMISARTAN TABLET FORMULATION BY 23 FACTORIAL DESIGN EMPLOYING HPβCD, PRIMOJEL AND TWEEN 80

The objective of the present study is optimization of telmisartan tablet formulation employing HPβCD, Primojel, and Tween 80 by 23 factorial design to achieve NLT 85% dissolution in 10 min. Eight telmisartan tablet formulations were prepared using selected combinations of the three factors as per 23 factorial design. Telmisartan tablets were prepared by direct compression method and were evaluated. ANOVA of K1 values indicated that the individual and combined effects of HPβCD (Factor A) and Primojel (Factor B) in influencing the dissolution rate of telmisartan tablets are highly significant (P < 0.01). The effect of Tween 80 (Factor C) and the combined effects of AC, BC and ABC are not significant (P˃0.05).Telmisartan tablet formulations Fb, Fbc and Fabc disintegrated rapidly within 1 min and gave very rapid dissolution of telmisartan more than 90% in 10 min . The increasing order of dissolution rate (K1) observed with various formulations was Fc< F1< Fac< Fa< Fabc< Fab< Fb< Fbc. The polynomial equation describing the relationship between the response, percent drug dissolved in 10min (Y) and the levels of HPβCD (X1) , Primojel (X2) and Tween 80 (X3) based on the observed results was found to be Y = 56.097 + 3.663(X1) + 38.036(X2) – 9.146(X1X2) – 3.77(X3) – 3.38(X1X3) + 2.073(X2X3) + 1.767(X1X2X3).Based on the above equation, the formulation of optimized telmisartan tablets with NLT 85% dissolution in 10 min require HPβCD at 1:3.5 ratio of drug: HPβCD, Primojel at 26.626% of drug and HPβCD content , and Tween 80 at 1% of drug and HPβCD content. The optimized telmisartan tablet formulation gave 85.55% dissolution in 10 min fulfilling the target dissolution requirement. Formulation of telmisartan tablets with NLT 85% dissolution in 10 min could be optimized by 23 factorial design. Key words: Telmisartan tablets, Optimization, Hydroxy propyl β-cyclodextrin, Primojel, Tween 80, Factorial Design