Composition for Administering an NMDA Receptor Antagonist to a Subject

Abstract

The invention provides extended release amantadine compositions for once daily administration of amantadine to a subject.

What is claimed is: 
     
         1 . An extended release pharmaceutical composition in tablet or capsule form for oral administration to a human subject in need of amantadine therapy consisting of:
 a. amantadine, or a pharmaceutically acceptable salt thereof;   b. one or more excipients, wherein at least one of said excipients modifies the release of the amantadine from the composition; and   c. if the composition is in capsule form, a capsule;   wherein the composition has an in vitro dissolution profile in water that is less than 5% in 15 minutes, less than 10% in 30 minutes, 40% to 80% in 6 hours, and greater than or equal to 90% in 12 hours as measured using a USP type II (paddle) dissolution system at 50 rpm, at a temperature of 37±0.5° C.;   and wherein the composition is designed for once daily administration of a therapeutically effective amount of amantadine, or a pharmaceutically acceptable salt thereof.   
     
     
         2 . The composition of  claim 1 , wherein the rate of release of the amantadine from said composition is less than 10% of the rate for an IR formulation of amantadine over the first hour. 
     
     
         3 . The composition of  claim 1  or  2 , wherein the therapeutically effective amount of the amantadine, or the pharmaceutically acceptable salt thereof, is 25 mg to 500 mg. 
     
     
         4 . The composition of  claim 1  or  2 , wherein the therapeutically effective amount of the amantadine, or the pharmaceutically acceptable salt thereof, is 200 mg to 500 mg. 
     
     
         5 . The composition of  claim 1  or  2 , wherein the therapeutically effective amount of the amantadine, or the pharmaceutically acceptable salt thereof, is 300 mg to 500 mg. 
     
     
         6 . The composition of  claim 1  or  2 , wherein said composition has an in vitro dissolution of at least 70% at 10 hours in a dissolution media having a pH of 1.2 as measured using a USP type II (paddle) dissolution system at 50 rpm, at a temperature of 37±0.5° C. 
     
     
         7 . The composition of  claim 1  or  2 , wherein said composition has an in vitro dissolution of at least 80% at 10 hours in a dissolution media having a pH of 1.2 as measured using a USP type II (paddle) dissolution system at 50 rpm, at a temperature of 37±0.5° C.