Title:  Microcrystalline cellulose particles having active core

United States Patent:  6,149,943

Assignee:  McNeil-PPC, Inc. (Skillman, NJ)

Filed:  November 2, 1999

The present invention provides a core of predominately microcrystalline cellulose, on which an active drug is layered onto the core via solution coating. The coated particles have a narrower particle size distribution than coated granules provided by other processes. An optional final coating of a pharmaceutically acceptable polymeric coating is provided to provide tastemaking or controlled release, and protection of the drug-layered particles.

SUMMARY OF THE INVENTION

The present invention is directed to a particle which comprises a seed core comprised predominately of microcrystalline cellulose, having an average particle size of about 180 microns, to which a pharmaceutically active ingredient in solution is layered onto the microcrystalline cellulose by spray coating. The seed core and the pharmaceutically active material is then overcoated with a suitable polymer. The mean particle diameter of the final coated particle containing the pharmaceutically active ingredient and polymer is less than about 325 microns, which makes it smaller than traditional particles.

More specifically the present invention comprises a particle comprising a center core of predominately microcrystalline cellulose having an average particle size of about 160 to about 220 microns with a particle size standard deviation of from about 75 to about 200;

pharmaceutically active material coating the center core of microcrystalline cellulose;

wherein the coated particle is from about 40 to about 75 weight percent microcrystalline cellulose;

pharmaceutically active ingredient is from about 25 to about 60 weight percent; and a particle size of from about 200 to about 325 microns and a particle size standard deviation of from about 30 to about 175 microns.

The present invention also includes a method for making a pharmaceutically active particle comprising

providing a center core of predominately microcrystalline cellulose having an average particle size of about 160 to about 220 microns with a particle size standard deviation of from about 75 to about 200;

coating said microcrystalline cellulose with a pharmaceutically active ingredient;

wherein the coated particle is from about 40 to about 75 weight percent microcrystalline cellulose; the pharmaceutically active ingredient is from about 25 to about 60 weight percent; and has a particle size of from about 200 to about 325 microns and a particle size standard deviation of from about 30 to about 175 microns; wherein the coating of the microcrystalline cellulose is performed in the absence of a granulation step.

Claim 1 of 9 Claims

I claim:

1. A particle comprising:

a center core of greater than about 90 weight percent microcrystalline cellulose having an average particle size of about 160 to about 220 microns with a particle size standard deviation of from about 75 to about 200 microns;

pharmaceutically active material coating the center core of microcrystalline cellulose and a tapped bulk density of from about 0.40 to about 0.45 grams per cubic centimeters;

wherein the coated particle is from about 40 to about 75 weight percent microcrystalline cellulose; pharmaceutically active ingredient is from about 25 to about 60 weight percent; and a particle size of from about 200 to about 325 microns and a particle size standard deviation of from about 30 to about 175 microns.

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