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 dry granulation method of producing granules comprising:
mixing a first powder comprising at least one active ingredient 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 a 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 granules.
2. The method of claim 1 , wherein the twin-screw extruder comprises two screws that are fully intermeshing, co-rotating screws.
3. The method of claim 1 , wherein a barrel temperature at one location along a length of the screw barrel is different from a barrel temperature at another location along the length of the screw barrel.
4. The method of claim 1 , wherein a first zone closest to an outlet of the screw barrel has a lower barrel temperature than a second zone at a center portion along the length of the screw barrel.
5. The method of claim 1 , wherein all temperatures along the length of the screw barrel are between about 50-100° C.
6. The method of claim 1 , wherein the twin-screw extruder does not have a die block for extruding the granules.
7. The method of claim 1 , wherein the powder mixture further comprises a lubricant.
8. The method of claim 7 , wherein the lubricant is added to the powder mixture before kneading the powder mixture.
9. The method of claim 7 , wherein the lubricant comprises about 0.01-1 wt % the powder mixture.
10. The method of claim 7 , wherein the lubricant is selected from the group consisting of magnesium stearate, zinc stearate, lithium stearate, calcium stearate, aluminum stearate, sodium stearyl fumarate, talc, glyceryl behenate, and colloidal silicon dioxide.
11. The method of claim 1 , 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.
12. The method of claim 1 , wherein all temperatures along the length of the screw barrel are below a melting point or a glass transition temperature of all components in the powder mixture.
13. The method of claim 1 , wherein the melting point or the glass transition temperature of the at least one carrier is lower than the melting point of the at least one active ingredient.
14. The method of claim 1 , wherein the powder mixture comprises two or more polymeric carriers.
15. The method of claim 1 , wherein the at least one carrier is selected from the group consisting of polysaccharides, povidones, acrylates, celluloses and polyols.
16. The method of claim 1 , 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.
17. The method of claim 1 , 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.
18. The method of claim 1 , 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.
19. The method of claim 1 , wherein the powder mixture further comprises at least one of a plasticizer, binder, filler, disintegrant, or organic acid.
20. The method of claim 1 , wherein the powder mixture further comprises an organic acid.
21. The method of claim 1 , wherein a screw speed of the twin-screw extruder is less than about 200 rpm.
22. The method of claim 1 , wherein a feed rate into the twin-screw extruder is less than about 400 g/hr.
23. The method of claim 1 , wherein the granules have an angle of repose of less than or equal to about 30.
24. The method of claim 1 , wherein the granules have a compressibility index of about 10-30.
25. The method of claim 1 , wherein the granules have a Hausner ratio of less than about 1.25.
26. The method of claim 1 , wherein the granules have a true density of about 1.15-1.35.
27. The method of claim 1 , wherein the granules have a surface area of about 0.05-0.45.
28. The method of claim 1 , further comprising pressing the granules into a tablet.
29. The method of claim 28 , wherein the tablet has a hardness of about 5-20 kp.
30. The method of claim 28 , wherein the tablet has a friability of less than about 0.5%.