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 oral dosage form containing between 1 mg and 100 mg of memantine, wherein said dosage form does not contain 10 mg of memantine, and wherein said dosage form is not prepared by the patient or a person administering the drug to the patient who divides the dosage form containing a larger dose of memantine.  
     
     
         2 . The oral dosage form of  claim 1  which contains 5 mg or 15 mg of memantine.  
     
     
         3 . The oral dosage form of  claim 2  which is a solid dosage form.  
     
     
         4 . The oral dosage form of  claim 3  which is a tablet.  
     
     
         5 . The oral dosage form of  claim 3  which contains 5 mg of memantine.  
     
     
         6 . The oral dosage form of  claim 3  which contains 15 mg of memantine.  
     
     
         7 . The oral dosage form of  claim 3  which contains 20 mg of memantine.  
     
     
         8 . A method of administering memantine to a patient in amount that is not about 10 mg, comprising administering to the patient an oral dosage form of memantine, wherein said dosage form is not prepared by the patient or a person administering the drug to the patient who divides the dosage form containing a larger dose of memantine.  
     
     
         9 . The method of  claim 8  wherein said dosage form contains 5 mg or 15 mg of memantine.  
     
     
         10 . The method of  claim 9  wherein said dosage form is a solid dosage form,  
     
     
         11 . The method of  claim 10  wherein said dosage form is a tablet.  
     
     
         12 . The method of  claim 10  wherein said tablet contains 5 mg of memantine.  
     
     
         13 . The method of  claim 10  wherein said tablet contains 15 mg of memantine.  
     
     
         14 . A packaged pharmaceutical product comprising individual oral dosage forms of memantine which contain 5 mg, 15 mg, or 20 mg of memantine.  
     
     
         15 . The packaged pharmaceutical product of  claim 14  which comprises individual oral dosage forms containing 5 mg of memantine, 10 mg of memantine, 15 mg of memantine, and 20 mg of memantine.  
     
     
         16 . The packaged pharmaceutical product of  claim 14  which comprises individual oral dosage forms containing 5 mg of memantine and 10 mg of memantine.  
     
     
         17 . A method of treating a patient with memantine, comprising a. administering a gradually increasing dose of memantine to said patient until the maintenance dose is reached, and b. continuing to administer said maintenance dose on a regular basis as long as memantine is needed, wherein the maintenance dose is reached in a sufficiently long period of time to significantly reduce adverse events, wherein the increment in which the dose of memantine is increased in successive dosages is less than 5 mg of memantine.  
     
     
         18 . The method of  claim 17  wherein the dose of memantine is increased by an increment of about 0.25 to about 0.5 mg each day until the maintenance dose is reached.