POLY AMPHIPHILIC COMPLEXES FOR THE DELIVERY OF A HYDROPHOBIC ACTIVE AGENT, COMPOSITIONS AND METHODS

The invention provides a complex comprising at least one hydrophobic active agent, an ionic polymer comprising a repetitive unit of formula (I): 5 I wherein R1 represents a hydrogen atom or a straight or branched chain alkyl group, preferably a straight or branched chain alkyl group comprising from 1 to 6 carbon atoms, for example a methyl group; R2 represents a straight or branched chain alkyl group which is substituted by a group which may have a positive charge at a physiological pH wherein the ionic polymer is a homopolymer or a random copolymer, wherein the repetitive unit of formula (I) in a random copolymer comprises (dimethylamino)ethyl 10 methacrylate, wherein the molar proportion of (dimethylamino)ethyl methacrylate repetitive units to the total number of repetitive units in a random copolymer is greater than 50%, and wherein the at least one hydrophobic active agent has a molecular weight of from 100 to 1500 g/mol; a complex for use in a method of medical treatment; a pharmaceutical composition; and a method of preparing a complex or pharmaceutical composition according to the invention which method comprises the steps of: 15 (a) dissolving the hydrophobic active agent and the ionic polymer in one or more non‐aqueous solvents to form the complex wherein the one or more non‐aqueous solvents are miscible with water; and (b) progressively replacing the one or more non‐aqueous solvents with water.