Therapeutic composition and methods

An oral drug delivery system comprising:

• a) a core comprising:
• a therapeutically effective amount of at least one active agent present in an amount of from about 50% to about 64% w/w of the core, wherein the at least one active agent is selected from the group consisting of colesevelam, pharmaceutically acceptable salts thereof, and combinations thereof, and
• a drug release controlling component capable of providing release of the at least one active agent primarily in a region of a patient selected from the group consisting of a lower gastrointestinal tract, a large intestine, a jejunum, a ileum, a cecum, a colon, a rectum, and combinations thereof,
• wherein the drug release controlling component comprises low viscosity hydroxypropyl methyl cellulose (HPMC) and high viscosity HPMC, and
• comprises at least one erodible matrix material selected from the group consisting of hydroxypropyl methylcellulose phthalate (HPMCP), hydroxypropylmethylcellulose acetate succinate (HPMCAS), hydroxypropyl methyl cellulose acetate trimellitate (HPMCAT), ethylhydroxy ethylcellulose (EHEC), and combinations thereof, wherein said at least one erodible matrix material is present in a concentration of about 5% to about 15% w/w of the core;
• b) a barrier coating encasing the core, wherein said barrier coating comprises HPMC, and
• c) an enteric coating on the barrier coating comprising hypromellose acetate succinate, and further comprising a plasticizer,
• wherein after ingestion by the patient the at least one active agent is released primarily in the region selected from the group consisting of the lower gastrointestinal tract, the large intestine, the jejunum, the ileum, the cecum, the colon, the rectum, and combinations thereof.