CPC A61K 31/5513 (2013.01) [A61K 9/20 (2013.01); A61K 9/48 (2013.01)] | 8 Claims |
1. A stable extended release pharmaceutical composition of Clozapine with one or more pharmaceutically acceptable excipients, comprising: a) granules, pellets, beads or spheroids comprising Clozapine with pharmaceutically acceptable excipients, b) a first seal coat layer comprising a hydrophilic polymer, c) an acidic coating comprising an acidic substance, d) a second seal coat layer comprising a hydrophilic polymer, (e) an extended release coating with a water insoluble polymer and a water soluble polymer, and (f) a third seal coat layer comprising a hydrophilic polymer,
wherein, the amount of the seal coating in the composition is from 2-20%; the amount of the acidic coating in the composition is from 20-40%; the amount of extended release coating in the composition is from 2-20%;
wherein, the hydrophilic polymer comprises hydroxypropyl methylcellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxyethyl methylcellulose, carboxymethylcellulose, polyethylene glycol, polyethylene oxides, or polyalcohols; the water insoluble polymer comprises Chitosan, polyurethanes, ethyl cellulose, cellulose acetate or waxes; and the water soluble polymer comprises hydroxypropyl methylcellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxyethyl methylcellulose, carboxymethylcellulose, polyethylene glycol, polyethylene oxides, or polyalcohols;
wherein the total impurities in the said pharmaceutical composition is not more than 2% w/w of Clozapine and wherein an assay of the quantity of Clozapine in the said pharmaceutical composition is from 95% to 105% upon storage at 40±2° C. and 75±5% relative humidity (RH) for 6 months, relative to the quantity of Clozapine in the pharmaceutical composition prior to storage; and
wherein the said composition comprises Clozapine having an effective particle size (D90) of less than about 10 micron that provides solubility of Clozapine of at least 20 mg/ml in 0.1N hydrochloric acid.
|