Details for Patent: 8,333,991

Title:	Gastric retained gabapentin dosage form
Abstract:	A method of treatment for epilepsy and other disease states is described, which comprises the delivery of gabapentin in a gastric retained dosage form.
Inventor(s):	Berner; Bret (Half Moon Bay, CA), Hou; Sui Yuen Eddie (Foster City, CA), Gusler; Gloria M. (Cupertino, CA)
Assignee:	Depomed, Inc. (Menlo Park, CA)
Filing Date:	Jul 19, 2012
Application Number:	13/553,622
Claims:	1. A method for administering a therapeutically effective amount of gabapentin to a human subject, comprising: administering a dosage form comprising gabapentin or a pharmaceutically acceptable salt thereof, wherein the dosage form comprises (a) at least one component that expands on contact with water, a gas-generating agent, and the gabapentin or pharmaceutically acceptable salt thereof; and (b) at least one hydrophilic membrane which encases at least the gas-generating agent; and whereby gabapentin is released from the dosage form into the upper gastrointestinal tract over about 5-12 hours at a rate sufficient to achieve a lower maximum plasma concentration than that provided by an immediate release dosage form comprising an equal amount of gabapentin, and bioavailability of gabapentin is at least 80% of that provided by the immediate release dosage form comprising an equal amount of gabapentin as measured by the area under the plasma concentration-time curve, AUC.sub.inf. 2. The method of claim 1, wherein the gas-generating agent releases carbon dioxide or nitrogen. 3. The method of claim 1, wherein the at least one component comprises a swellable polymer. 4. The method of claim 1, wherein the at least one hydrophilic membrane is in the form of a microporous membrane. 5. The method of claim 1, wherein the at least one hydrophilic membrane is in the form of a sachet. 6. The method of claim 1, wherein the dosage form further comprises a covering which encases the hydrophilic membrane. 7. The method of claim 1, wherein the dosage form is administered once-daily or twice-daily. 8. The method of claim 1, wherein the dosage form comprises between about 100 mg and about 4800 mg gabapentin. 9. The method of claim 1, wherein the dosage form comprises about 300 mg or about 600 mg gabapentin. 10. A method for treating a disorder, comprising: administering to a human subject a dosage form comprising gabapentin or a pharmaceutically acceptable salt thereof, wherein the dosage form comprises (a) at least one component that expands on contact with water, a gas-generating agent, and the gabapentin or pharmaceutically acceptable salt thereof; and (b) at least one hydrophilic membrane which encases at least the gas-generating agent; whereby gabapentin is released from the dosage form into the upper gastrointestinal tract over about 5-12 hours at a rate sufficient to achieve a lower maximum plasma concentration than that provided by an immediate release dosage form comprising an equal amount of gabapentin, and bioavailability of gabapentin is at least 80% of that provided by the immediate release dosage form comprising an equal amount of gabapentin as measured by the area under the plasma concentration-time curve, AUC.sub.inf. 11. The method of claim 10, wherein the gas-generating agent releases carbon dioxide or nitrogen. 12. The method of claim 10, wherein the disorder is a neuropathic pain, epilepsy, a movement disorder, or a psychiatric disorder. 13. A method for administering a therapeutically effective amount of gabapentin to a human subject, comprising: administering a dosage form comprising gabapentin or a pharmaceutically acceptable salt thereof, wherein the dosage form comprises a drug layer comprising gabapentin or pharmaceutically acceptable salt thereof; and a buoyant layer, whereby gabapentin is released from the dosage form into the upper gastrointestinal tract over about 5-12 hours at a rate sufficient to achieve a lower maximum plasma concentration than that provided by an immediate release dosage form comprising an equal amount of gabapentin, and bioavailability of gabapentin is at least 80% of that provided by the immediate release dosage form comprising an equal amount of gabapentin as measured by the area under the plasma concentration-time curve, AUC.sub.inf. 14. The method of claim 13, wherein the buoyant layer is a swelling layer. 15. A dosage form, comprising: gabapentin or a pharmaceutically acceptable salt thereof, wherein the dosage form comprises (a) at least one component that expands on contact with water, a gas-generating agent, and the gabapentin or pharmaceutically acceptable salt thereof; and (b) at least one hydrophilic membrane which encases at least the gas-generating, agent; and wherein upon ingestion of the dosage form by a human subject, gabapentin is released into the upper gastrointestinal tract over about 5-12 hours at a rate sufficient to achieve a lower maximum plasma concentration than that provided by an immediate release dosage form comprising an equal amount of gabapentin, and bioavailability of gabapentin is at least 80% of that provided by the immediate release dosage form comprising an equal amount of gabapentin as measured by the area under the plasma concentration-time curve, AUC.sub.inf. 16. The dosage form of claim 15, wherein the gas-generating agent releases carbon dioxide or nitrogen. 17. The dosage form of claim 15, further comprising a second therapeutic agent selected from the group consisting of a hydantoin, an iminostilbene, a valproate, a phenyltriazine, a barbiturate, a dexoybarbiturate, a benzodiazepine, a carbamate, an anticonvulsant other than gabapentin, a tricyclic antidepressant, levadopa, carbidopa, an opioid, lithium, carbamazepine, valproate, trifluoperazine, clonazepam, risperidone, lorazepam, venlafaxine, clozapine, olanzapine, a benzodiazepine, a neuroleptic, a serotonin reuptake inhibitor, buproprion, nefadone, venlaxatine, nefadone, diazepam, oxazepam, a dopaminergic agent, clonazepam, a triptine and ergotamine.