FORM 2
THE PATENT ACT 1970
(39 of 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10 and rule13)
1. TITLE OF THE INVENTION:
SOLID DOSAGE FORM OF LEVETIRACETAM
2. APPLICANT (S)
(a) NAME: WOCKHARDT LTD.
(b) NATIONALITY: INDIAN
(c) ADDRESS: Wockhardt Towers, Bandra-Kurla Complex, Bandra
(East), Mumbai - 400 051.
3. PREAMBLE TO THE DESCRIPTION
The present invention relates to pharmaceutical compositions of levetiracetam or salt thereof.
The following specification particularly describes the invention and the manner in which it is to be performed.
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4. Description
The present invention relates to pharmaceutical compositions of levetiracetam or salt thereof.
Levetiracetam, a single enantiomer, is (-)-(S)-a-ethyl-2-oxo-1-pyrrolidine acetamide, its molecular formula is C8H14N2O2 and its molecular weight is 170.21. Levetiracetam is chemically unrelated to existing antiepileptic drugs (AEDs). Levetiracetam is indicated as adjunctive therapy in the treatment of partial onset seizures in adults and children 4 years of age and older with epilepsy.

US Patent No 4,837,223 & US Patent No 4,837,224 disclose pharmaceutical composition comprising levetiracetam and a pharmaceutically acceptable solid or liquid diluent or carrier, substantially free from its S enantiomer.
US Application 20050143445 discloses crystalline forms I, II and III of Levetiracetam, process for making the same and pharmaceutical composition comprising crystalline form of levetiracetam.
It was noticed by the present inventors that as the percentage of levetiracetam exceeds 86% w/w in a unit dose composition, say tablet, the compression characteristics, content uniformity and bulk density of the granular mass to be compacted are severely affected. It is now surprisingly found that when however,
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the unit dose contains less than 86% of levetiracetam, and it is easily formulated and offers several advantages in handling.
One of the aspects of the present invention provides a unit dose pharmaceutical composition containing comprising 1gm levetiracetam or salt thereof wherein the composition comprises of not more than 86% by weight of levetiracetam along with pharmaceutically acceptable excipients.
The unit dose pharmaceutical composition includes one or more of tablet, capsule, granule, powder, sachet or pellet.
The pharmaceutical composition comprises of pharmaceutically acceptable excipients comprises of diluent, filler, binder, lubricant, sweetener, coloring and flavoring agent and glidant.
The suitable filler may be selected from a group Comprising one or more of lactose, corn starch, microcrystalline cellulose, mannitol, calcium phosphate, calcium sulfate, kaolin, sorbitol, powdered sugar and the like.
The suitable disintegrant may be one or more of microcrystalline cellulose, croscarmellose sodium, crosspovidone, sodium starch glycolate and the like.
The suitable binder may be one or more of sugars, gums, low molecular weight hydroxypropyl methylcellulose, polyvinyl pyrrolidone and hydroxypropyl cellulose.
The suitable lubricants may be selected from a group comprising one or more of mineral oils, vegetable oils and glyceryl esters of fatty acids wherein mineral oils, vegetable oils and glyceryl esters of fatty acids comprises hydrogenated vegetable oil, hydrogenated castor oil, light mineral oil, glycerol monostearate, glycerol monobehenate, glyceryl behenate, glyceryl palmitostearate and the like.
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The suitable glidant may be one or more of colloidal silicon dioxide, talc or the like.
The suitable coloring or flavoring agents include those approved for use by the United States Food and Drug Administration (FDA) and are well known to those skilled in the art.
The compressed tablets may optionally be coated with functional coat that rapidly disintegrates or dissolves in water or the environment of use. The coat may be a conventional sugar or polymeric film coating, which is applied in a coating pan or by conventional spraying techniques. Preferred materials for the coat are commercially available under the OPADRY tradename. Generally, the coat surrounding the core will comprise from about 1 to 5% based on the total weight of the tablet.
While the present invention has been described in terms of its specific embodiments, certain modifications and equivalents will be apparent to those skilled in the art and are intended to be included within the scope of the present invention.
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EXAMPLE 1
Table 1: Composition of Levetiracetam tablets.
No Ingredients Qty/Tablet
(ma)
1 Levetiracetam 1000.000
2 Corn Starch (Pure-dent B890) 178.000
3 Croscarmellose sodium (Ac-di-sol) 50.000
4 Povidone (PVP K-30) 4.000
5 Purified water qj>.
6 Croscarmellose sodium (Ac-di-sol) 50.000
7 Colloidal silicon dioxide (Aerosil 200) 5.000
8 Talc 4.000
9 Magnesium Stearate 9.000
Core Tablet weight 1300
10 Opadry 03F28415 White 30
I Coated Tablet weight 11330.000
Procedure: The Intragranular material comprising Levetiracetam, corn starch and Croscarmellose sodium were sifted individually and then mixed using a suitable blender. The blend was granulated with Povidone binder solution, dried in fluidised bed and obtained granules were mixed with presifted extragranular material comprising Croscarmellose sodium,Colloidal silicon dioxide, talc and Magnesium Stearate. The obtained blend was compressed using a suitable tooling to form a tablet that is optionally coated with dispersion of opadry.
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WE CLAIM:
1. A unit dose pharmaceutical composition containing comprising 1gm levetiracetam or salt thereof wherein the composition comprises of not more than 86% by weight of levetiracetam along with pharmaceutically acceptable excipients.
2. A pharmaceutical composition of claims 1 wherein pharmaceutically acceptable excipients comprises of diluent, filler, binder, lubricant, sweetener, coloring and flavoring agent and glidant.
3. A pharmaceutical composition of claim 1 wherein the dosages form is tablet, capsule, granule, powder, sachet or pellet.
4. A pharmaceutical composition of claim 1 wherein the dosages form has 1 gm of levetiracetam.
5. A pharmaceutical composition of claim 1 having between 80-86% by weight of levetiracetam.