Patent ID: 7927628

Claim:
A sustained-release preparation, which is obtained by dissolving or dispersing a pharmacologically active substance in a molten mixture of a low-melting-point substance and a pH-independent water-insoluble polymer; spraying and cooling the resulting liquid to obtain particles; melt-coating the surface of the thus obtained particles with (1) a fine powder of ethylcellulose or (2) a fine powder of ethylcellulose and at least one member selected from the group consisting of talc, magnesium stearate and titanium oxide, the content of the ethylcellulose in the fine powder being not less than 60 wt %; and adhering a powder of at least one member selected from the group consisting of lactose, talc, magnesium stearate and titanium oxide to the melt-coated surface; the low-melting-point substance being at least one member selected from the group consisting of glycerol fatty acid esters, polyglycerol fatty acid esters, glycerol fatty acids and citric acid, stearic acid, palmitic acid, stearyl alcohol, and cetanol; and the pH-independent water-insoluble polymer being at least one member selected from the group consisting of ethylcellulose, aminoalkyl methacrylate copolymer RS, aminoalkyl methacrylate copolymer RL, cellulose acetate, cellulose acetate butyrate, and cellulose acetate propionate; and the content of the pH-independent water-insoluble polymer in the molten mixture being 0.5 to 60 wt. % relative to the low-melting-point substance.