Patent ID: 7863316

Claim:
An extended release tablet of levetiracetam comprising a) from about 30% to about 85% w/w of the tablet of levetiracetam and about 1% to about 50% w/w of the tablet of a water dispersible rate controlling polymer selected from the group consisting of hydroxyethyl cellulose, hydroxypropyl cellulose, sodium alginate, carbomer, sodium carboxymethyl cellulose, xanthan gum, guar gum, locust bean gum, poly vinyl acetate, polyvinyl alcohol and hydroxypropyl methylcellulose b) a functional coating comprising: i) from about 40% to about 90% w/w of the functional coating of a hydrophobic rate controlling polymer selected from the group consisting of cellulose ethers, cellulose acetate, polyvinyl acetate, neutral polymers of methacrylic acid esters, polyvinyl alcohol-maleic anhydride copolymers and mixtures thereof; ii) from about 10% to about 60% w/w of the functional coating of a channeling agent selected from the group consisting of copolyvidone, polyvinyl pyrrolidone, polyethylene glycols, hydroxyethyl cellulose, hydroxypropyl methylcellulose and mixtures thereof; and iii) optionally, a plasticizer selected from, oligomers, copolymers, oils, low molecular weight polyols having aliphatic hydroxyls, glycol ethers, poly(propylene glycol), multi-block polymers, single block polymers, triacetin, propylene glycol, glycerin, ethylene glycol, 1,2-butylene glycol, 2,3-butylene glycol, styrene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, poly(ethylene glycol) compounds, monopropylene glycol monoisopropyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, diethylene glycol monoethyl, ether, sorbitol lactate, ethyl lactate, butyl lactate, ethyl glycolate, dibutylsebacate, acetyltributylcitrate, triethyl citrate, acetyl triethyl citrate, tributyl citrate, allyl glycolate and mixtures thereof; and c) optionally a polymer based nonfunctional coat.