Immediate release formulations of 1-aminocyclohexane compounds, memantine and neramexane

Abstract

The present invention relates to an immediate release solid oral dosage form containing 1-aminocyclohexanes, preferably memantine or neramexane, and optionally a pharmaceutically acceptable coating, wherein the active ingredient exhibits dose proportionality and is released at a dissolution rate of more than about 80% within about the first 60 minutes following entry of said form into a use environment. The dosage form is direct compressed and has a hardness within the range of between about 3 and about 40 Kp, exhibits an average T max within the range of about 2 to about 8 hours with an active ingredient load within the range of about 2.5 to about 150 mg. The formulation allows for dose-proportional compositions for once daily or b.i.d. dosing, while maintaining a steady average range of T max .

1 . An immediate release solid oral dosage form comprising (i) an active ingredient selected from the group consisting of neramexane, optical isomers, diastereomers, enantiomers, hydrates, and pharmaceutically acceptable salts thereof, (ii) a pharmaceutically acceptable filler selected from microcrystalline cellulose, wherein the microcrystalline cellulose is present in a range from 20% w/w to 95% w/w, and (iii) a disintegrant, said dosage form exhibiting dose-proportionality and releasing said active ingredient at a rate of more than about 80% within about the first 60 minutes following entry of said form into a use environment, wherein said dosage form exhibits an average T max  within the range of about 2 to about 8 hours with an active ingredient load within the range of about 2.5 to about 150 mg, and wherein said dosage form is free of lactose. 
     
     
         2 . The immediate release solid oral dosage form according to  claim 1  wherein said oral dosage form releases said active ingredient at a rate of more than about 80% within the first 30 minutes following entry of said form into a use environment. 
     
     
         3 . The immediate release solid oral dosage form according to  claim 2  wherein said oral dosage form releases said active ingredient at a rate of more than about 80% within the first 15 minutes following entry of said form into a use environment. 
     
     
         4 . The immediate release solid oral dosage form according to  claim 1 , wherein said active ingredient is neramexane mesylate. 
     
     
         5 . The immediate release solid oral dosage form according to  claim 4 , wherein the active ingredient is present in an amount within the range from about 2% w/w to about 20% w/w. 
     
     
         6 . The immediate release solid oral dosage form according to  claim 1 , further comprising one or more pharmaceutically acceptable carriers, excipients, anti-adherents, fillers, stabilizing agents, binders, colorants, disintegrants, glidants, and lubricants. 
     
     
         7 . The immediate release solid oral dosage form according to  claim 1  wherein said solid oral dosage form is a tablet. 
     
     
         8 . The immediate release solid oral dosage form of  claim 1 , wherein the solid oral dosage form further comprises a pharmaceutically acceptable coating.