A pharmaceutical composition for administration to a subject in need thereof comprising a dose of an aminosalicylate active agent chosen from 4-amino salicylic acid, 5-amino salicylic acid, a 4-amino salicylic acid pro-drug being a compound that yields 4-amino salicylic acid at some point following administration, and a 5-amino salicylic acid pro-drug being a compound that yields 5-amino salicylic acid at some point following administration, wherein the 4-amino salicylic acid pro-drug or the 5-amino salicylic acid pro-drug is chosen from sulfasalazine, olsalazine (5,5' azo-bis salicylic acid), 4,5'-azo-bis salicylic acid, 4,4'-azo-bis salicylic acid, 5,4' azo-bis salicylic acid, and balsalazide, and pharmaceutically acceptable salts and esters thereof; at least one water-soluble polymer chosen from polyvinyl alcohol, polyvinylpyrrolidone, methylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, or polyethylene glycol, and mixtures thereof or at least one water-insoluble polymer chosen from ethylcellulose, cellulose acetate, cellulose propionate, cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate phthalate, cellulose triacetate, poly (methyl methacrylate), poly (ethyl methacrylate), poly (butyl methacrylate), poly (isobutyl methacrylate), and poly (hexyl methacrylate), poly (isodecyl methacrylate), poly (lauryl methacrylate), poly (phenyl methacrylate), poly (methyl acrylate), poly (isopropyl acrylate), poly (isobutyl acrylate), poly (octadecyl acrylate), poly (ethylene), poly (ethylene) low density, poly (ethylene) high density, poly (ethylene oxide), poly (ethylene terephthalate), poly (vinyl isobutyl ether), poly (vinyl acetate), poly (vinyl chloride) or polyurethane, and mixtures thereof; and at least one pharmaceutically acceptable excipient chosen from carriers, fillers, extenders, binders, absorbents, lubricant and stabilizers; wherein the composition exhibits: (a) a drug-release profile that is independent of surrounding pH and (b) a dissolution profile, when tested in a U.S.P. Type II apparatus (paddles) at 37°C and 50 rpm, in pH 6.8 buffer for the test: 1 hour: less than or equal to 20% drug released; 2 hours: less than or equal to 35% drug released; 3 hours: less than or equal to 50% drug released; 4 hours: less than or equal to 60% drug released; 6 hours: less than or equal to 75% drug released; and 12 hours: from 25% to 100% drug released; and wherein upon administration, the composition exhibits: (c) at least one ratio chosen from a total urine recovery or total plasma ratio of N-acetylated metabolite of the active agent to the active agent greater than or equal to 10:1, and a Cmax ratio of N-acetylated metabolite of the active agent to the active agent greater than or equal to 5:1; and (d) from greater than 30% to 100% of the dose of the active agent excreted in the urine as N-acetylated metabolite of the active agent and the active agent. (a) a drug-release profile that is independent of surrounding pH and (b) a dissolution profile, when tested in a U.S.P. Type II apparatus (paddles) at 37°C and 50 rpm, in pH 6.8 buffer for the test: 1 hour: less than or equal to 20% drug released; 2 hours: less than or equal to 35% drug released; 3 hours: less than or equal to 50% drug released; 4 hours: less than or equal to 60% drug released; 6 hours: less than or equal to 75% drug released; and 12 hours: from 25% to 100% drug released; and 1 hour: less than or equal to 20% drug released; 2 hours: less than or equal to 35% drug released; 3 hours: less than or equal to 50% drug released; 4 hours: less than or equal to 60% drug released; 6 hours: less than or equal to 75% drug released; and 12 hours: from 25% to 100% drug released; and (c) at least one ratio chosen from a total urine recovery or total plasma ratio of N-acetylated metabolite of the active agent to the active agent greater than or equal to 10:1, and a Cmax ratio of N-acetylated metabolite of the active agent to the active agent greater than or equal to 5:1; and (d) from greater than 30% to 100% of the dose of the active agent excreted in the urine as N-acetylated metabolite of the active agent and the active agent.