Twin-screw dry granulation for producing solid formulations
A dry granulation process using a twin-screw extruder for granulating a powder mixture which includes at least one active ingredient and at least one carrier. The process includes steps of kneading the powder mixture in the screw barrel of the twin-screw extruder at a barrel temperature below a melting point of the at least one active ingredient and a melting point or a glass transition temperature of the at least one carrier to provide a kneaded powder mixture, and extruding the kneaded powder mixture to form granules. Granules and tablets produced using the dry granulation process in the twin-screw extruder are also provided.
1. A granule produced by the method comprising:
mixing a first powder comprising at least one active ingredient having a crystal structure and a second powder comprising at least one carrier to form a powder mixture;
feeding the powder mixture to a twin-screw extruder without a solvent, liquid binder, or meltable binder;
kneading the powder mixture in a heated screw barrel of the twin-screw extruder, wherein all temperatures along the length of the screw barrel are below a melting point of the at least one active ingredient and below a melting point or a glass transition temperature of the at least one carrier to form a kneaded powder mixture; and
extruding the kneaded powder mixture to form the granule, wherein the granule is free of solvents, liquid binders, and meltable binders, has a surface area of about 0.05-0.45, has an angle of repose of less than or equal to about 30, and the crystal structure of the at least one active ingredient is preserved in the granule.
2. A granule comprising:
at least one active ingredient having a crystal structure and at least one carrier having a melting point or a glass transition temperature lower than a melting point of the at least one active ingredient,
wherein the granule is free of solvents, liquid binders, and meltable binders, has a compressibility index of about 10-30, a Hausner ratio of less than about 1.25, a surface area of about 0.05-0.45, and an angle of repose of less than or equal to about 30, and the crystal structure of the at least one active ingredient is preserved in the granule.
3. The granule of claim 2 , wherein the granule has a true density of about 1.15-1.35.
4. The granule of claim 2 , wherein the at least one active ingredient is selected from the group consisting of heat-sensitive active pharmaceutical ingredients, dehydration-sensitive active pharmaceutical ingredients, poorly-compressible active pharmaceutical ingredients, and high-dosage active pharmaceutical ingredients.
5. The granule of claim 2 , wherein the at least one carrier is selected from the group consisting of polysaccharides, povidones, acrylates, celluloses and polyols.
6. The granule of claim 2 , wherein the at least one carrier is selected from the group consisting of homopolymers and copolymers of N-vinyl pyrrolidone, copolymers of N-vinyl pyrrolidone and vinyl acetate or vinyl propionate; cellulose esters and cellulose ethers, hydroxyalkylcelluloses, hydroxyalkylalkylcelluloses, cellulose phthalates, cellulose succinates; polyethylene oxide, polypropylene oxide, copolymers of ethylene oxide and propylene oxide; polyacrylates, polymethacrylates, polyacrylamides; vinyl acetate polymers, polyvinyl alcohol, oligo- and polysaccharidesand mixtures of one or more thereof.
7. The granule of claim 2 , wherein the at least one carrier is selected from the group consisting of hydroxylpropylcellulose, ethylcellulose, carboxymethylcellulose, hydroxyethylcellulose, methylcellulose, ethylhydroxyethylcellulose, hydroxyethylmethylcellulose, hydrophobically modified hydroxyethylcellulose, hydrophobically modified ethylhydroxyethylcellulose, carboxymethylhydroxyethylcellulose, and carboxymethyl hydrophobically modified hydroxyethylcellulose.
8. The granule of claim 2 , wherein the at least one carrier is a polymeric carrier having a molecular weight in a range of about 2,000-2,000,000 Daltons.
9. An oral dosage formulation comprising the granule of claim 2 , wherein the oral dosage formulation is a capsule, pellet, sachet, powder, or tablet.