Patent ID: 7790200

Claim:
A controlled release pellet consisting of: a) a water soluble non-pareil core; wherein the diameter of the non-pareil core is between 60 and 80 mesh; b) a drug layer applied to the non-pareil core wherein the drug layer consists of: (i) 70-99 weight percent based upon the total weight of the drug layer of metoprolol succinate; and (ii) 1-25 weight percent based upon the total weight of the drug layer of a water soluble binder which is polyvinyl pyrrolidone or hydroxypropyl methylcellulose; and (iii) optionally a surfactant; c) a controlled release coating surrounding the drug layer wherein the controlled release coating consists of: (i) 75-90 weight percent based upon the total weight of the controlled release coating of a water insoluble polymer; (ii) 2-10 weight percent based upon the total weight of the controlled release coating of an enteric material selected from the group consisting of hydroxypropyl methylcellulose phthalate, cellulose acetate phthalate, methacrylic acid copolymers, zein and mixtures thereof; and (iii) 5-15 weight percent based upon the total weight of the controlled release coating of an emulsifier; and d) optionally an immediate release form of metoprolol; wherein, the controlled release pellet exhibits the following dissolution profile when tested in a USP Type 2 apparatus at 75 rpm and 37° C. in a phosphate buffer with a pH of 7.5: 0-40% of the metoprolol is released after 2 hours; 5-50% of the metoprolol is released after 4 hours; 25-80% of the metoprolol is released after 8 hours; and not less than 50% of the metoprolol is released after 16 hours.