In a delayed release formulation comprising a core containing a drug and a delayed release coating for providing intestinal release, release of the drug in the colon is accelerated by including an isolation layer between the core and the delayed release coating. The delayed release coating comprises an inner layer and an outer layer. The outer layer comprises a pH dependently soluble polymeric material which has a pH threshold at about pH 5 or above. The inner layer comprises a soluble polymeric material which is soluble in intestinal fluid or gastrointestinal fluid, said soluble polymeric material being selected from the group consisting of a polycarboxylic acid polymer that is at least partially neutralised, and a non-ionic polymer, provided that, where said soluble polymeric material is a non-ionic polymer, said inner layer comprises at least one additive selected from a buffer agent and a base.