Drug delivery compositions and methods

Claim 1

A method of preparing a composition useful as a system to introduce and transport medically useful compositions in the body of mammals by oral, tissue absorptive, inhalation, or parenteral administration; the method being characterised in that it comprises forming a core material comprising core particles of a material having a desired particle size; forming a mixture of one or more surface active agents, water and one or more physiologically-active compounds and emulsifying the mixture to produce a two phase coacervate composition comprising a coacervate phase and an equilibrium water phase, the physiologically-active compound being contained in one or both of said phases; forming the core material particles with one or both of the coacervate phases or contacting the core material with one or both of the coacervate phases to embed the physiologically-active compound within a coacervate-based core material matrix or to encapsulate the core material particles within an encapsulating coacervate-based film containing the physiologically-active compound.

Claim 2

A method of preparing a composition useful as a system to introduce and transport medically useful compositions in the body of mammals by oral, tissue absorptive, inhalation, or parenteral administration; the method being characterised in that it comprises forming a core material comprising core particles of a material having a desired particle size; forming a mixture of one or more surface active agents, water and one or more physiologically-active compounds and emulsifying the mixture to produce a two phase coacervate composition comprising a coacervate phase and an equilibrium water phase, the physiologically-active compound being contained in one or both of said phases; forming the core material particles with one or both of the coacervate phases or contacting the core material with one or both of the coacervate phases to embed the physiologically-active compound within a coacervate-based core material matrix or to encapsulate the core material particles within an encapsulating coacervate-based film containing the physiologically-active compound.

Claim 5

A method as claimed in any one of the preceding claims, characterised in that the coacervate mixture includes two surface active agents, at least one of which is a polymer having a weight average molecular weight of 300,000 or less, the two surface active agents being preferably a phospholid and a surface active protein, for example lecithin and polymerized albumin.

Claim 6

A method as claimed in any one of the preceding claims, further characterised by drying the composition to form a powder capable of being reconstituted by the addition of a physiologically acceptable liquid.

Claim 7

A method as claimed in any one of the preceding claims, characterised in that the or each surface active agent is added in monomeric form and a polymerization initiator is added to said composition, said polymerization initiator being capable of and present in an amount sufficient to polymerize the surface active agent during processing of said coacervate mixture.

Claim 8

A method as claimed in any one of the preceding claims, characterised in that the core material is formed from a coacervate-based matrix and the matrix is encapsulated with a coacervate-based film.

Claim 9

A method as claimed in any one of the preceding claims, characterised in that the physiologically-active compound comprises insulin, an atrial peptide, or a perhalogenated compound, for example a perfluorinated hydrocarbon, perfluoroiodinated hydrocarbon, perfluorinated amine, perfluoroiodinated amine, perfluorinated ether, perfluoroiodinated ether, perfluorinated hydrocarbon-iodine complex, or mixtures thereof, preferably perfluorodecalin, perfluoroiododecalin, perfluorotributylamine, perfluorotripropylamine, perfluoro-N,N-dimethylcyclo­hexylmethylamine, perfluorotrimethyl-bicyclo[3.3.1]nonane, iodinated perfluorodecalin or perfluoroiodide.

Claim 10

A method as claimed in any one of the preceding claims, characterised in that the physiologically active compound in one or both of the two coacervate phases is bound as particles in a coacervate matrix and within a coacervate-based aqueous film; and further including the steps of separating the particles; and adding a hydrocolloid to the particles in an amount of 2-20% w/v based on the weight of the coacervate mixture to form a gel-like surface film surrounding the physiologically active compound.

Claim 11

A method as claimed in any one of the preceding claims, characterised by adding an anti-oxidant to the coacervate mixture during preparation.

Claim 12

A method as claimed in any one of the preceding claims, characterised in that it includes the step of adding a physiologically acceptable alcohol to the coacervate mixture to form a three layer liquid comprising a lower polar layer, a middle layer, and an upper non-polar layer; separating the middle layer from the other two layers; adding a second surface active agent to the separated middle layer to form a second two-phase liquid comprising a lower polar layer and an upper non-polar layer; and adding a physiologically-active compound to one or both of said layers formed from said second two-phase liquid.

Claim 15

A method as claimed in any one of the preceding claims, characterised in that the core particles are encapsulated by a coacervate-based film; and in that the encapsulated particles are contacted with a second coacervate composition to form an additional coacervate-­derived film on the particles.

Claim 34

A method of administering a physiologically-­active compound to a mammal comprising topical application of a coacervate composition according to any one of claims 16 to 23 on the skin of a mammal; and applying sound waves to the topically applied coacervate composition to drive the physiologically-active compound into the skin.