Delayed release of drug to a colon is achieved from delayed release formulation comprising a core and its coating. The core comprises thge drug, and coating comprises outer layer and at least one layer between the core and outer layer selected from the group consisting of isolation and inner layers. Outer layer comprises a mixture of first polymeric material which is susceptible to attack by colonic bacteria, and second polymeric material having pH threshold at about pH 5 or above. Inner layer comprises third polymeric material soluble in intestinal fluid or gastrointestinal fluid, said third polymeric material being selected from at least partially neutralised polycarboxylic acid and non-ionic polymer. In embodiments in which the third polymeric material is non-ionic polymer, inner layer comprises at least one buffer agent and a base. Isolation layer comprises non-ionic polymer soluble in intestinal fluid or gastrointestinal fluid. Outer layer is applied directly to inner or isolation layer using coating preparation formed by combining first polymeric material in aqueous medium with second polymeric material in organic medium.
