Abstract: 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.

Abstract: 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.

Abstract: Delayed release of a drug to the colon is achieved from a delayed release formulation comprising a core and a coating for the core. The core comprises a drug and the coating comprises an outer layer and at least one layer between the core and the outer layer selected from the group consisting of an isolation layer and an inner layer. The outer layer comprises a mixture of a first polymeric material which is susceptible to attack by colonic bacteria, and a second polymeric material which has a pH threshold at about pH 5 or above. The inner layer comprises a third polymeric material which is soluble in intestinal fluid or gastrointestinal fluid, said third polymeric material being selected from an at least partially neutralised polycarboxylic acid and a non-ionic polymer. In embodiments in which the third polymeric material is a non-ionic polymer, the inner layer comprises at least one of a buffer agent and a base.

Abstract: Apparatus for testing the solubility of a medical dosage form includes a chamber (12) for holding a solvent medium (18), in the preferred embodiment a bicarbonate based buffer system. The apparatus also includes a pH probe (66) which is connectable to a supply of carbon dioxide (32, 34),as well as to a supply of helium (40), the supplies being controlled by a control unit (50). The control unit (50) monitors changes in pH of the solvent medium (18) and, as appropriate, feeds pH increasing and/or pH reducing gas from the supplies(32, 34, 40) into the chamber (12). The control unit (50) is able to maintain a uniform pH during testing or to provide a dynamically adjustable pH during testing, for example to three or more different pH levels in order to test the performance of a drug carrier at different levels of acidity or alkalinity for example, mimicking the conditions of the gastrointestinal tract.

Abstract: Delayed release of a drug to the colon is achieved from a delayed release formulation comprising a core and a coating for the core. The core comprises a drug and the coating comprises an outer layer and at least one layer between the core and the outer layer selected from the group consisting of an isolation layer and an inner layer. The outer layer comprises a mixture of a first polymeric material which is susceptible to attack by colonic bacteria, and a second polymeric material which has a pH threshold at about pH 5 or above. The inner layer comprises a third polymeric material which is soluble in intestinal fluid or gastrointestinal fluid, said third polymeric material being selected from an at least partially neutralised polycarboxylic acid and a non-ionic polymer. In embodiments in which the third polymeric material is a non-ionic polymer, the inner layer comprises at least one of a buffer agent and a base.

Abstract: Delayed release of a drug to the colon is achieved from a delayed release formulation comprising a core and a coating for the core. The core comprises a drug and the coating comprises an inner layer and an outer layer. The outer layer comprises a mixture of a first polymeric material which is susceptible to attack by colonic bacteria, and a second polymeric material which has a pH threshold at about pH 5 or above. The inner layer comprises a third polymeric material which is soluble in intestinal fluid or gastrointestinal fluid, said third polymeric material being selected from an at least partially neutralised polycarboxylic acid and a non-ionic polymer. In embodiments in which the third polymeric material is a non-ionic polymer, the inner layer comprises at least one of a buffer agent and a base.

Abstract: A delayed release coating comprising a mixture of a first material selected from starch; amylose; amylopectin; chitosan; chondroitin sulfate; cyclodextrin; dextran; pullulan; carrageenan; scleroglucan; chitin; curdulan and levan, and a second material which has a pH threshold at about pH 5 or above, is used to target release of a drug from a core to the intestine, particularly the colon.

Abstract: A method of producing microparticles having a median diameter up to 100 ?m and the microparticles so produced are described. The method includes the steps of providing a solvent having a bioactive dispersed or dissolved therein and a vehicle dissolved therein, carrying out an emulsification in a non-solvent phase to produce an emulsion containing the bioactive and the vehicle in a solvent phase, and evaporating the solvent to leave the microparticles, wherein a mixture of at least two surfactants is employed to stabilize the emulsion and wherein the mixture has a hydrophilic-lipophilic balance (HLB) of up to 8.

Abstract: A method of producing microparticles having a median diameter up to 100 ?m and the microparticles so produced are described. The method includes the steps of providing a solvent having a bioactive dispersed or dissolved therein and a vehicle dissolved therein, carrying out an emulsification in a non-solvent phase to produce an emulsion containing the bioactive and the vehicle in a solvent phase, and evaporating the solvent to leave the microparticles, wherein a mixture of at least two surfactants is employed to stabilize the emulsion and wherein the mixture has a hydrophilic-lipophilic balance (HLB) of up to 8.