CA2634059C — Method of producing drug-containing wax matrix particles, extruder to be used in the method and sustained-release preparation containing cilostazol

USPTO Abstract

The present invention aims to provide a method for producing, by a simple method, drug-containing wax matrix granules, particularly drug-containing wax matrix granules having an average particle diameter of 1 mm or lower, while avoiding liquid blockage due to the recrystallization of a molten drug during the period from a melting step to a spray step. Drug-containing wax matrix granules having at least one wax and at least one drug are produced by the following steps (i) and (ii): (i) supplying the at least one drug and the at least one wax to an extruder in which the temperature of a barrel and the temperature of a die are adjusted to be higher than the melting point of the at least one wax; and (ii) while melting and kneading the at least one drug and the at least one wax in the extruder to give a molten kneaded drug and wax, spraying the molten kneaded drug and wax into an atmosphere having a temperature lower than the melting point of the wax from a spray nozzle directly mounted onto a die provided at a top end of the barrel of the extruder, thereby forming the mixture into granules.