Sustained Release Pharmaceutical Compositions for Highly Water Soluble Drugs

Abstract

The present invention provides pharmaceutical compositions for controlled release of pharmaceutically active agents, especially those with a high water solubility, high dose, and/or short half-life. In addition, the present application provides methods for preparing and using such pharmaceutical compositions.

What is claimed is: 
     
         1 . A sustained release pharmaceutical tablet, said tablet comprising:
 tramadol micronized at a dose selected from the group consisting of 90 mg, 180 mg, 300 mg and 600 mg;   a matrix comprising hydroxypropylmethyl cellulose (HMPC) and the micronized tramadol dispersed in the matrix;   microcrystalline cellulose; and   a tablet lubricant.   
     
     
         2 . The pharmaceutical tablet of  claim 1 , wherein the pharmaceutically active agent contributes greater than 15% of the total weight of the pharmaceutical composition. 
     
     
         3 . The pharmaceutical tablet of  claim 1 , wherein the pharmaceutically active agent contributes greater than 50% of the total weight of the pharmaceutical composition. 
     
     
         4 . The pharmaceutical tablet of  claim 1 , wherein the pharmaceutically active agent is present in an amount of about 50% to about 80% by weight. 
     
     
         5 . The pharmaceutical tablet of  claim 1 , wherein the hydrophilic polymer is present in an amount of about 15% to about 50% by weight. 
     
     
         6 . The pharmaceutical tablet of  claim 1 , wherein the HPMC is a high molecular weight HPMC in an amount of about 20% to about 30% by weight of the tablet. 
     
     
         7 . The pharmaceutical tablet of  claim 1 , wherein the tableting lubricant is present in an amount of about 1% to about 3% by weight of the tablet. 
     
     
         8 . The pharmaceutical tablet of  claim 7 , wherein the tablet lubricant is magnesium stearate. 
     
     
         9 . The pharmaceutical tablet of  claim 1 , further comprising a coating on the tablet. 
     
     
         10 . The pharmaceutical tablet of  claim 9 , wherein said coating is a release-controlling layer. 
     
     
         11 . The pharmaceutical tablet of  claim 9 , wherein said coating constitutes about 1% to about 5% by weight of the tablet. 
     
     
         12 . The pharmaceutical tablet of  claim 9 , wherein said tablet is coated with a layer of film containing ethyl cellulose. 
     
     
         13 . The pharmaceutical tablet of  claim 9 , wherein the tramadol dose is 90 mg. 
     
     
         14 . The pharmaceutical tablet of  claim 9 , wherein the tramadol dose is 180 mg. 
     
     
         15 . The pharmaceutical tablet of  claim 9 , wherein the tramadol dose is 300 mg. 
     
     
         16 . The pharmaceutical tablet of  claim 9 , wherein the tramadol dose is 600 mg. 
     
     
         17 . A method for reducing pain in an animal, said method comprising:
 administering a tramadol micronized tablet at a dose selected from the group consisting of 90 mg, 180 mg, 300 mg and 600 mg or a fragment thereof, said tablet comprising a matrix comprising hydroxypropylmethyl cellulose (HMPC) and the micronized tramadol dispersed in the matrix;   microcrystalline cellulose; and   a tablet lubricant, to reduce pain in the animal.   
     
     
         18 . The method of  claim 17 , wherein the tramadol dose is 180 mg. 
     
     
         19 . The method of  claim 17 , wherein the tramadol dose is 300 mg. 
     
     
         20 . The method of  claim 17 , wherein the tramadol dose is 600 mg.