MULTIPARTICULATE SELECTIVE SEROTONIN AND NOREPINEPHRINE REUPTAKE INHIBITOR FORMULATION

1 . A multiparticulate oral pharmaceutical composition comprising a plurality of particles comprising:

(a) a core comprising: (i) a therapeutically effective amount of a selective serotonin and norepinephrine reuptake inhibitor and a pharmaceutically acceptable excipient;

(b) a seal coating that comprises only water soluble materials and wherein the seal coating is applied directly to the core; and

(c) a delayed release coating comprising an enteric material and at least one pharmaceutically acceptable processing aid and wherein the delayed release coating is applied directly to the seal coating.

2 . The pharmaceutical composition as defined in claim 1 wherein the selective serotonin and norepinephrine reuptake inhibitor is selected from the group consisting of venlafaxine, desvenlafaxine, sibutramine, nefazodone, milnacipran, desipramine, duloxetine, bicifadine or pharmaceutically acceptable salts thereof.

3 . The pharmaceutical composition as defined in claim 2 wherein the selective serotonin and norepinephrine reuptake inhibitor is duloxetine or pharmaceutically acceptable salts thereof.

4 . The pharmaceutical composition as defined in claim 1 wherein the particles are delayed release coated granules, microtablets, beads or pellets.

5 . The pharmaceutical composition as defined in claim 1 wherein the core comprises an inert starting seed coated with a drug layer comprising the selective serotonin and norepinephrine reuptake inhibitor and a binder.

6 . The pharmaceutical composition as defined in claim 1 wherein the seal coating is a mixture of two water soluble polymers selected from the group consisting of hydroxypropyl methylcellulose, hydroxypropyl cellulose, polyvinylpyrrolidone, polyvinyl alcohol and polyethylene glycol.

7 . The pharmaceutical composition as defined in claim 1 wherein the delayed release coating comprises the enteric material and a processing aid that is slightly soluble, very slightly soluble, insoluble or mixtures of the foregoing.

8 . The pharmaceutical composition as defined in claim 7 wherein the delayed release coating consists of the enteric material and very slightly soluble or insoluble processing aids.

9 . The pharmaceutical composition as defined in claim 8 wherein the processing aids are selected from the group consisting of plasticizers, lubricants, fillers, glidants, anti-adherents or mixtures of the foregoing.

10 . The pharmaceutical composition as defined in claim 1 wherein the delayed release coating comprises the enteric material and an acetylalkyl citrate plasticizer.

11 . The pharmaceutical composition as defined in claim 10 wherein the acetylalkyl citrate plasticizer is acetyltributyl citrate.

12 . The pharmaceutical composition as defined in claim 1 wherein the delayed release coating comprises at least two enteric materials wherein each enteric material dissolves at a different pH.

13 . The pharmaceutical composition as defined in claim 1 wherein the composition is a capsule.

14 . The pharmaceutical composition as defined in claim 1 wherein the composition is a tablet.

15 . A multiparticulate oral pharmaceutical composition comprising a plurality delayed release coated particles wherein the delayed release coated particle consists essentially of:

(a) a core comprising: (i) a therapeutically effective amount of duloxetine or a pharmaceutically acceptable salt thereof; (ii) a inert starting seed; and (iii) a water soluble binder;

(b) a seal coating that comprises only water soluble materials and wherein the seal coating is applied directly to the core; and

(c) a delayed release coating consisting essentially of an enteric material and slightly soluble, very slightly soluble or insoluble processing aids.

16 . The pharmaceutical composition as defined in claim 15 wherein the delayed release coating comprises at least two enteric materials wherein each enteric material dissolves at a different pH.

17 . The pharmaceutical composition as defined in claim 15 wherein the composition is a capsule.

18 . The pharmaceutical composition as defined in claim 15 wherein the composition is a tablet.

19 . The pharmaceutical composition as defined in claim 15 wherein the delayed release coating further consists of an acetylalkyl citrate plasticizer.

20 . The pharmaceutical composition as defined in claim 19 wherein the acetylalkyl citrate plasticizer is acetyltributyl citrate.