Patent ID: 6534090
Filing Date: 2003-03-18
Classification: A61K

Abstract:
An oral osmotic controlled drug delivery system for a sparingly soluble drug comprising:a. a wall made of acylated cellulose, b. a core surrounded by the wall, the core comprising (i) finely particulate anhydrous carbamazepine, (ii) a mixture of xanthan gum and croscarmellose sodium as a polymeric swelling agent which exhibits controlled swelling and the wall does not rupture or burst, (iii) a crystal habit modifier in whose presence, upon contact with an aqueous medium, the anhydrous carbamazepine is transformed into cuboidal or rod-shaped crystals of the dihydrate of carbarnazepine, or mixtures thereof, and (iv) a water-soluble compound for inducing osmosis, the wall being impermeable to the components of the drug-containing core, but permeable to water, and c. a passageway through the wall for releasing the components present in the core to the surrounding environment.