Gastroretentive dosage system and process of preparation thereof

1. A gastroretentive capsule dosage system consisting of:

(a) a shell filled with a powder consisting of an active ingredient, wherein the active ingredient is selected from the group consisting of acyclovir, gabapentin, pregabalin, trimetazidine, feropenem, carbidopa, levodopa, methyldopa, verapamil, propranolol, carvedilol, atenolol, albuterol, pirbuterol, nifedipine, nimodipine, nicardipine, amlodipine, prazosin, guanabenz, allopurinol, metoprolol, oxprenolol, baclofen, sumatriptan, benazepril, enalapril, lisinopril, captopril, quinapril, moxipril, indolapril, olindapril, retinapril, spirapril, cilazapril, perindopril, ramipril, zofenopril, fosinopril, nitrofurantoin, valacyclovir, azithromycin, inosine, didanosine, pranobex, tribavirin, vidarabine, simvastatin, pravastatin, atorvastatin, lovastatin, selegiline, midazolam, lithium carbonate, cimetidine, ranitidine, famotidine, nizatidine, bifentidine, nifentidine, roxatidine, omeprazole, lansoprazole, pantoprazole, antacids selected from magnesium carbonate, aluminum carbonate, aluminum hydroxide, magnesium oxide and sucralfate, carbenoloxalone, misoprostol, pirenzepine, telenzepine, bismuth salts, metronidazole, ciprofloxacin, clarithromycin, amoxicillin, cephalexin, ascorbic acid, folic acid, vitamin E, furosemide, topiramide, hydrochlorothiazide, orlistat and pharmaceutically acceptable salts, esters or prodrugs thereof; and

(b) an extended-release coating over the shell, wherein the extended-release coating is applied in an amount of 3% to 15% w/w based on the total weight of the dosage system and comprises one or more extended release polymer(s) selected from group consisting of cellulose acetate, ethylcellulose and copolymers of methacrylate/trimethyl aminoethyl methacrylate, and the extended-release coating optionally comprises one or more coating additive(s), said additives being selected from the group consisting of fillers, plasticizers, opacifiers, coloring agents, lubricants/glidants and mixtures thereof.

2. A gastroretentive dosage system consisting of:

(a) a shell filled with a powder consisting of an active ingredient, wherein the active ingredient is selected from the group consisting of acyclovir, gabapentin, pregabalin, trimetazidine, feropenem, carbidopa, levodopa, methyldopa, verapamil, propranolol, carvedilol, atenolol, albuterol, pirbuterol, nifedipine, nimodipine, nicardipine, amlodipine, prazosin, guanabenz, allopurinol, metoprolol, oxprenolol, baclofen, sumatriptan, benazepril, enalapril, lisinopril, captopril, quinapril, moxipril, indolapril, olindapril, retinapril, spirapril, cilazapril, perindopril, ramipril, zofenopril, fosinopril, nitrofurantoin, valacyclovir, azithromyc in, inosine, didanosine, pranobex, tribavirin, vidarabine, simvastatin, pravastatin, atorvastatin, lovastatin, selegiline, midazolam, lithium carbonate, cimetidine, ranitidine, famotidine, nizatidine, bifentidine, nifentidine, roxatidine, omeprazole, lansoprazole, pantoprazole, antacids selected from magnesium carbonate, aluminum carbonate, aluminum hydroxide, magnesium oxide and sucralfate, carbenoloxalone, misoprostol, pirenzepine, telenzepine, bismuth salts, metronidazole, ciprofloxacin, clarithromycin, amoxicillin, cephalexin, ascorbic acid, folic acid, vitamin E, furosemide, topiramide, hydrochlorothiazide, orlistat and pharmaceutically acceptable salts, esters or prodrugs thereof;

(b) an extended-release layer over the shell, wherein the extended-release layer is applied in an amount of 3% to 15% w/w based on the total weight of the dosage system and comprises one or more extended release polymer(s) selected from group consisting of cellulose acetate, ethylcellulose and copolymers of methacrylate/trimethyl aminoethyl methacrylate, and the extended-release layer optionally comprises one or more coating additive(s), said additives being selected from the group consisting of fillers, plasticizers, opacifiers, coloring agents, lubricants/glidants and mixtures thereof; and

(c) an immediate-release layer comprising an active ingredient over the extended-release layer.

3. The gastroretentive dosage system of claim 2 , wherein the active ingredient present in the shell and the active ingredient present in the immediate-release layer are the same or different.

4. A process for the preparation of a gastroretentive dosage system, wherein the process comprises the steps of:

(a) filling an empty shell, wherein filling the empty shell consists of filling the empty shell with an active ingredient in powder form, wherein the active ingredient is selected from the group consisting of acyclovir, gabapentin, pregabalin, trimetazidine, feropenem, carbidopa, levodopa, methyldopa, verapamil, propranolol, carvedilol, atenolol, albuterol, pirbuterol, nifedipine, nimodipine, nicardipine, amlodipine, prazosin, guanabenz, allopurinol, metoprolol, oxprenolol, baclofen, sumatriptan, benazepril, enalapril, lisinopril, captopril, quinapril, moxipril, indolapril, olindapril, retinapril, spirapril, cilazapril, perindopril, ramipril, zofenopril, fosinopril, nitrofurantoin, valacyclovir, azithromycin, inosine, didanosine, pranobex, tribavirin, vidarabine, simvastatin, pravastatin, atorvastatin, lovastatin, selegiline, midazolam, lithium carbonate, cimetidine, ranitidine, famotidine, nizatidine, bifentidine, nifentidine, roxatidine, omeprazole, lansoprazole, pantoprazole, antacids selected from magnesium carbonate, aluminum carbonate, aluminum hydroxide, magnesium oxide and sucralfate, carbenoloxalone, misoprostol, pirenzepine, telenzepine, bismuth salts, metronidazole, ciprofloxacin, clarithromycin, amoxicillin, cephalexin, ascorbic acid, folic acid, vitamin E, furosemide, topiramide, hydrochlorothiazide, orlistat and pharmaceutically acceptable salts, esters or prodrugs thereof; and

(b) coating the shell consisting of the active ingredient with a solution or dispersion of one or more extended-release polymer(s) and one or more coating additive(s), wherein the extended-release polymer(s) is applied in an amount of 3% to 15% w/w based on the total weight of the dosage system and comprises one or more extended release polymer(s) selected from the group consisting of cellulose acetate, ethylcellulose and copolymers of methacrylate/trimethyl aminoethyl methacrylate, and the one or more coating additive(s) are selected from the group consisting of fillers, plasticizers, opacifiers, coloring agents, lubricants/glidants and mixtures thereof.

5. A process for the preparation of a gastroretentive dosage system, wherein the process comprises the steps of:

(a) filling an empty shell, wherein filling the empty shell consists of filling the empty shell with an active ingredient in powder form, wherein the active ingredient is selected from the group consisting of acyclovir, gabapentin, pregabalin, trimetazidine, feropenem, carbidopa, levodopa, methyldopa, verapamil, propranolol, carvedilol, atenolol, albuterol, pirbuterol, nifedipine, nimodipine, nicardipine, amlodipine, prazosin, guanabenz, allopurinol, metoprolol, oxprenolol, baclofen, sumatriptan, benazepril, enalapril, lisinopril, captopril, quinapril, moxipril, indolapril, olindapril, retinapril, spirapril, cilazapril, perindopril, ramipril, zofenopril, fosinopril, nitrofurantoin, valacyclovir, azithromycin, inosine, didanosine, pranobex, tribavirin, vidarabine, simvastatin, pravastatin, atorvastatin, lovastatin, selegiline, midazolam, lithium carbonate, cimetidine, ranitidine, famotidine, nizatidine, bifentidine, nifentidine, roxatidine, omeprazole, lansoprazole, pantoprazole, antacids selected from magnesium carbonate, aluminum carbonate, aluminum hydroxide, magnesium oxide and sucralfate, carbenoloxalone, misoprostol, pirenzepine, telenzepine, bismuth salts, metronidazole, ciprofloxacin, clarithromycin, amoxicillin, cephalexin, ascorbic acid, folic acid, vitamin E, furosemide, topiramide, hydrochlorothiazide, orlistat and pharmaceutically acceptable salts, esters or prodrugs thereof;

(b) coating the shell consisting of the active ingredient with a solution or dispersion of one or more extended-release polymer(s) and one or more optional coating additive(s), wherein the extended-release polymer(s) is applied in an amount of 3% to 15% w/w based on the total weight of the dosage system and comprises one or more extended release polymer(s) selected from the group consisting of cellulose acetate, ethylcellulose and copolymers of methacrylate/trimethyl aminoethyl methacrylate, and the one or more optional coating additive(s) are selected from the group consisting of fillers, plasticizers, opacifiers, coloring agents, lubricants/glidants and mixtures thereof; and

(c) coating the above coated shells with a solution or dispersion of the active ingredient, one or more binder(s) and one or more coating additive(s).

6. The gastroretentive capsule dosage system of claim 1 , wherein the extended-release coating further comprises one or more water soluble polymers selected from the group consisting of hydroxypropylmethylcellulose, hydroxypropylcellulose, hydroxyethyl cellulose, methylcellulose and polyvinylpyrrolidone.