Patent ID: 7964215

Claim:
A delayed release pharmaceutical composition in solid dosage form for oral administration comprising a core comprising a therapeutically effective amount of mesalamine and a pH-sensitive coating comprising a mixture of two different pH sensitive polymers: a first pH sensitive polymer that dissolves at a pH of about 7 or greater and a second pH sensitive polymer that dissolves at a pH of about 6 or greater, wherein the weight ratio of the first pH sensitive polymer to the second pH sensitive polymer ranges from about 2:1 to about 4:1 and the percent weight gain resulting from the addition of said pH sensitive coating ranges from about 10% up to and including 15%, wherein the average percentage amount of mesalamine released from the composition in an USP apparatus II, 900 mL at 37° C., at the conclusion of a three stage dissolution test consisting of a first stage wherein said pharmaceutical composition is stirred for 2 hours at 100 rpm in 0.1N HCl solution, a second stage wherein said composition is stirred for 1 hour at 100 rpm in solution buffered to a pH of 6.0 and a third stage wherein said composition is stirred for 2 hours at 50 rpm, is less than about 20% (w/w) when the third stage is a solution buffered to a pH of 6.5; is about 10% to about 60% (w/w) when the third stage is a solution buffered to a pH of 6.8; and at least about 80% (w/w) when the third stage is a solution buffered to a pH of 7.2.