Anti-influenza sustained-release pellet and preparation method thereof

The invention discloses an anti-influenza sustained-release pellet and a preparation method thereof. The pellet comprises a pellet core, an isolation layer coating and a controlled-release layer coating. The pellet core consists of anti-influenza spray-dried powder, polylactic acid-glycolic acid copolymer and an excipient; the isolation layer coating consists of Opadry; and the controlled-releaselayer coating consists of ethyl cellulose and controlled-release layer coating auxiliary materials. The controlled-release layer coating auxiliary materials consist of glycerol triacetate, tween-80, stearic acid, 5 parts of talcum powder and PVPK30. The anti-influenza spray-dried powder, the polylactic acid-glycolic acid copolymer, microcrystalline cellulose and starch are taken as raw materials,the pellet core is prepared by an extrusion and rounding method, and ethanol is taken as a wetting agent; the Opadry is taken as the isolation layer coating; and the ethyl cellulose are performed to and the controlled-release