Patent ID: 8298576

Claim:
A sustained release formulation of topiramate for oral administration to a mammalian subject comprising an immediate release bead population (IR), a first extended release bead population (XR 1 ), and a second extended release bead population (XR 2 ), wherein: (a) the IR bead population comprises topiramate up to 10% by wt of the total amount of topiramate in the formulation and 0.1-10% by wt of a binder, wherein the topiramate and binder form a coating on inert carrier particles, wherein the coated inert carrier particles are not coated with a release controlling coating, and wherein the IR bead population releases greater than or equal to 80% of its topiramate in a continuous manner over less than or equal to 1 hour; (b) the XR 1 bead population comprises topiramate up to 20% by wt of the total amount of topiramate in the formulation, wherein the topiramate is a coating on inert carrier particles, wherein the topiramate coated inert carrier particles are further coated with a release controlling coating material, wherein the coating material comprises 2-15% by weight of the topiramate coated inert carrier particles, and wherein the XR 1 bead population releases 80% of its topiramate in a continuous manner over less than or equal to 4 hours; and, (c) the XR 2 bead population comprises topiramate at least 80% by weight of the total amount of topiramate in the formulation, wherein the topiramate is a coating on inert carrier particles, wherein the topiramate coated inert carrier particles are coated with a release controlling coating material, wherein the coating material comprises 2-15% by weight of the topiramate coated inert carrier particles, and wherein the XR 2 bead population releases 80% of its topiramate in a continuous manner over less than 8 hours; wherein the release controlling coating materials comprise methylcellulose, ethylcellulose, hydroxypropyl cellulose, hydroxypropylmethyl cellulose, cellulose acetate, cellulose acetate phthalate, polyvinyl alcohol, polyacrylates, polymethacrylates or copolymers thereof, and wherein the XR 1 and XR 2 bead populations have their own specific rates of release.