Continuous release formulations

Claim 2

A pharmaceutical composition comprising a pharmacologically useful polypeptide and a pharmaceutically or veterinarily acceptable, amphipathic, non-cross-linked linear, branched or graft block copolymer, which has a minimum weight average molecular weight of 5,000, in which the hydrophobic component is biodegradable or hydrolytically unstable under normal physiological conditions, and the hydrophilic component may or may not be biodegradable, the composition being capable of absorbing water to form a hydrogel when placed in water or an aqueous physiological-type environment in an.animal body.

Claim 3

A composition as claimed in claim 1 wherein the pharmacologically useful polypeptide is selected from oxytocin, vasopressin, adrenocorticotrophic hormone, epidermal growth factor, prolactin, luliberin or luteinising hormone releasing hormone, growth hormone, growth hormone releasing factor, insulin, somatostatin, glucagon, interferon, gastrin, tetragastrin, pentagastrin, urogastrone, secretin, calcitonin, enkephalins, endorphins, angiotensins, renin, bradykinin, bacitracins,. polymyxins, colistins, tyrocidin, gramicidines, and synthetic analogues, modifications and pharmacologically active fragments thereof, monoclonal antibodies and soluble vaccines.

Claim 4

A composition as claimed in claim 1 wherein the poly-peptide is □Glu-His-Trp-Ser-Tyr-D-Ser(O-tBu)-Leu-Arg-Pro-Azgly-NH 2'

Claim 5

A composition as claimed in claim 1, 2 or 3 wherein the pharmaceutically or veterinarily acceptable amphipathic copolymer is a linear block copolymer of the formula A m (BA) n or B m (AB) n wherein m is 0 or 1, n is an integer, A is a pharmaceutically or veterinarily acceptable hydrophobic polymer and B is a pharmaceutically or veterinarily acceptable hydrophilic polymer, or the amphipathic copolymer is a graft or branched block copolymer of the formula AB n or BA n wherein A, B and n have the meanings stated above and wherein respectively either A or B is a backbone polymer with n units of a monomer or polymer B or A respectively grafted onto it.

Claim 6

A composition as claimed in claim 4 wherein the pharmaceutically or veterinarily acceptable hydrophobic polymer A is selected from poly(D-, L- and DL-lactic acids), poly(D-, L- and DL-lactides), polyglycolic acid, polyglycolide, poly-∈-caprolactone, poly(3-hydroxybutyric acid), non-therapeutic hydrophobic polypeptides, polyacetals of the formula:- wherein R is a hydrocarbon radical and n has the meaning stated above, polycarbonates or polyorthoesters of the formula:- wherein R and n have the meaning stated above, and copolymers of the formula:- wherein R and n have the meanings stated above, and copolymers derived from two or more monomers from which the above polymers are derived; and the pharmaceutically or veterinarily acceptable hydrophilic polymer B is selected from polyvinyl alcohol, polyvinylpyrrolidone, polyethylene oxide, polyethylene glycol, polyacrylamide, polymethacrylamide, dextran, alginic acid, sodium alginate, and gelatine, copolymers of two or more of the monomers from which the above polymers are derived, and polyoxyethylene/polyoxypropylene block copolymers.

Claim 7

A pharmaceutically or veterinarily acceptable amphipathic, non-cross-linked linear, branched or graft block copolymer, which has a minimum weight average molecular weight of 5,000, in which the hydrophobic component is biodegradable or hydrolytically unstable under normal physiological conditions, and the hydrophilic component may or may not be biodegradable, the copolymer being capable of absorbing water to form a hydrogel when placed in water or an aqueous physiological-type environment in an animal body.

Claim 8

A pharmaceutically or veterinarily acceptable amphipathic, non-cross-linked linear, branched or graft block copolymer, which has a minimum weight average molecular weight of 5,000, in which the hydrophobic component is biodegradable or hydrolytically unstable under normal physiological conditions, and the hydrophilic component may or may not be biodegradable, the copolymer being capable of absorbing water to form a hydrogel when placed in water or an aqueous physiological-type environment in an animal body.

Claim 9

A copolymer as claimed in claim 6 wherein the pharmaceutically or veterinarily acceptable amphipathic copolymer is a linear block copolymer of the formula A m (BA) n or B m (AB) n wherein m is 0 or 1, n is an integer, A is a pharmaceutically or veterinarily acceptable hydrophobic polymer and B is a pharmaceutically or veterinarily acceptable hydrophilic polymer, or the amphipathic copolymer is a graft or branched block copolymer of the formula AB n or BA n wherein A, B and n have the meanings stated above and wherein respectively either A or B is a backbone polymer with n units of a monomer or polymer B or A respectivey grafted onto it.

Claim 10

A copolymer as claimed in claim 7 wherein the pharmaceutically or veterinarily acceptable hydrophobic polymer A is selected from poly (D-, L- and DL-lactic acids), poly(D-, L- and DL-lactides), polyglycolic acid, polyglycolide, poly-E-caprolactone, poly(3-hydroxybutyric acid), non-therapeutic hydrophobic polypeptides, polyacetals of the formula:- wherein R is a hydrocarbon radical, and n has the meaning stated above, polycarbonates or polyorthoesters of the formula:- wherein R and n have the meanings stated above, and copolymers of the formula:- wherein R and n have the meanings stated above, and copolymers derived from two or more monomers from which the above polymers are derived; and the pharmaceutically or veterinarily acceptable hydrophilic polymer B is selected from polyvinyl alcohol, polyvinylpyrrolidone, polyethylene oxide, polyethylene glycol, polyacrylamide, polymethacryalamide, dextran, alginic acid, sodium alginate, and gelatine, and copolymers of two or more of the monomers from which the above polymers are derived, and polyoxyethylene/polyoxypropylene block copolymers.

Claim 11

A process for the manufacture of a copolymer as claimed in claim 7 which comprises copolymerising monomer or polymer A and monomer or polymer B by graft copolymerisation, polycondensation or polyaddition.

Claim 12

A pharmaceutical or veterinary composition comprising a non-peptide, pharmacologically active compound and a copolymer as claimed in claim 6.