The present application discloses a sustained release composition in pellet form, wherein the core of the pellet comprises:(a) a therapeutically effective amount of a medicament；(b) 0.5 to 50% by weight of a water-soluble polymer； and(c) 1 to 25% by weight of a water-insoluble polymer applied as an aqueous latex dispersion and subsequently the water is removed, wherein the sum of the percentages of the medicament, the water-insoluble polymer and the water-soluble polymer is equal to or less than 100%. It also discloses methods of making this composition.
