Administrable compositions

A composition suitable for administration to a subject, the composition comprising pharmacologically acceptable pre-formed solid particulate material dispersed throughout a pharmacologically acceptable liquid carrier, the particulate material having a largest dimension that is less than 0.5 microns and being maintained in the dispersed state by a steric stabilizer such that a dispersion is obtained which is stable over two weeks when diluted in a 0.15M NaCl solution,

• wherein the steric stabiliser is a polymeric material comprising a steric stabilising polymeric segment and an anchoring polymeric segment, one or both of which are derived from one or more ethylenically unsaturated monomers that have been polymerised by a living polymerisation technique,
• wherein the steric stabilising polymeric segment is different from the anchoring polymeric segment, and
• wherein the anchoring polymeric segment has an affinity toward the surface of the particulate material and secures the stabiliser to the particulate material, and
• wherein the steric stabiliser is a block copolymer having a number average molecular weight of less than 30,000.