Beta – cyclodextrin

Telmisartan is an angiotensin II (AT1) receptor antagonist used in the treatment of hypertension. The drug is practically insoluble in water and insoluble in the pH range 3-9. The principal aim of this work is to improve the dissolution profile of telmisartan by solid dispersion and to find out the effect of sodium starch glycolate and β – cyclodextrin on the dissolution profile of telmisartan tablets. The study also includes optimization of the amount of sodium starch glycolate and β – cyclodextrin by a 32 full factorial design. Other excipients used in the study are microcrystalline cellulose (Avicel PH-101), D- mannitol, magnesium stearate and talc. Both sodium starch glycolate and β – cyclodextrin had contribution towards the enhanced release profile of telmisartan (about 80 % drug is released in 40 minutes) but the effect of β – cyclodextrin is more pronounced as revealed from response surface plots as well as from their corresponding contour plots. The optimized amount of β – cyclodextrin and sodium starch glycolate was found to be 2.0 gm and 1.6 gm respectively. The predicted and observed responses for the optimized solid dispersions shown no significant difference (paired t-test, p – value = 0.2834 and 0.3403 for percentage drug released at 20 and 40 minutes respectively).