MICROPARTICLES CONTAINING PHYSIOLOGICALLY ACTIVE PEPTIDE, METHOD FOR PREPARING THE SAME, AND PHARMACEUTICAL COMPOSITION COMPRISING THE SAME

1 . A microparticle comprising: an ionic complex of physiologically active peptide and water-soluble polymer; and a biodegradable, water-insoluble polymer.

2 . The microparticle according to claim 1 , wherein the physiologically active peptide is selected from LHRH agonists, somatostatin and analogs thereof, glucagon-like peptides (GLP), parathyroid hormone and analogs thereof, insulin-like growth factors, epidermal growth factors, platelet-derived growth factors, fibroblast growth factors, transforming growth factors, growth hormone releasing factors, amylin analogs, peptide YY (PYY), protein synthesis-stimulating peptides, gastrin inhibitory peptides, vasoactive intestinal peptides, and pharmaceutically acceptable salts thereof.

3 . The microparticle according to claim 1 , wherein the water-soluble polymer is polylactic acid having at least one terminal carboxyl group or a derivative thereof, and is one or more selected from the group consisting of polylactic acid, polylactide, polyglycolide, polymandelic acid, polycaprolactone, polyanhydride and copolymers thereof.

4 . The microparticle according to claim 1 , wherein the water-soluble polymer is selected from the group consisting of compounds represented by Formulae 1 to 6 below:

RO—CHZ-[A] n -[B] m —COOM  [Formula 1]

wherein A is —COO—CHZ—; B is —COO—CHY—, —COO—CH 2 CH 2 CH 2 CH 2 CH 2 — or —COOCH 2 CH 2 OCH 2 ; R is hydrogen atom, or acetyl group, benzoyl group, decanoyl group, palmitoyl group, methyl group or ethyl group; each of Z and Y independently is hydrogen atom, methyl group or phenyl group; M is H, Na, K, or Li; n is an integer of 1 to 30; and m is an integer of 0 to 20,

RO—CHZ—[COO—CHX] p —[COO—CHY′] q —COO—CHZ—COOM  [Formula 2]

wherein X is methyl group; Y′ is hydrogen atom or phenyl group; p is an integer of 0 to 25 and q is an integer of 0 to 25 provided that p+q is an integer of 5 to 25; R is hydrogen atom, or acetyl group, benzoyl group, decanoyl group, palmitoyl group, methyl group or ethyl group; M is H, Na, K, or Li; and Z is hydrogen atom, methyl group or phenyl group,

RO—PAD-COO—W-M′  [Formula 3]

wherein W-M′ is

PAD is selected from the group consisting of D,L-polylactic acid, D-polylactic acid, polymandelic acid, copolymer of D,L-lactic acid and glycolic acid, copolymer of D,L-lactic acid and mandelic acid, copolymer of D,L-lactic acid and caprolactone, and copolymer of D,L-lactic acid and 1,4-dioxan-2-one; R is hydrogen atom, acetyl group, benzoyl group, decanoyl group, palmitoyl group, methyl group or ethyl group; and M is independently H, Na, K, or Li,

S—O—PAD-COO-Q  [Formula 4]

wherein S is L is

—NR 1 — or -0- in which R 1 is hydrogen atom or C 1-10 alkyl; Q is CH 3 , CH 2 CH 3 , CH 2 CH 2 CH 3 , CH 2 CH 2 CH 2 CH 3 , or CH 2 C 6 H 5 ; a is an integer of 0 to 4; b is an integer of 1 to 10; M is H, Na, K, or Li; PAD is one or more selected from the group consisting of D,L-polylactic acid, D-polylactic acid, polymandelic acid, copolymer of D,L-lactic acid and glycolic acid, copolymer of D,L-lactic acid and mandelic acid, copolymer of D,L-lactic acid and caprolactone, and copolymer of D,L-lactic acid and 1,4-dioxan-2-one,

wherein R′ is —PAD-O—C(O)—CH 2 CH 2 —C(O)—OM, in which PAD is selected from the group consisting of D,L-polylactic acid, D-polylactic acid, polymandelic acid, copolymer of D,L-lactic acid and glycolic acid, copolymer of D,L-lactic acid and mandelic acid, copolymer of D,L-lactic acid and caprolactone, and copolymer of D,L-lactic acid and 1,4-dioxan-2-one, and M is H, Na, K, or Li; and a is an integer of 1 to 4,

YO—[—C(O)—(CHX) a —O—] m —C(O)—R—C(O)—[—(CHX′) b —C(O)—] n —OZ  [Formula 6]

wherein each of X and X′ is independently hydrogen, alkyl or aryl; each of Y and Z is independently H, Na, K, or Li; each of m and n is independently an integer of 0 to 95 provided that 5<m+n<100; each of a and b is each independently an integer of 1 to 6; and R is substituted or unsubstituted —(CH 2 ) k — in which k is an integer of 0 to 10, divalent alkenyl having 2 to 10 carbon atoms, divalent aryl having 6 to 20 carbon atoms, or a combination thereof.

5 . The microparticle according to claim 1 , wherein the biodegradable, water-insoluble polymer is one or more selected from the group consisting of polylactide, polyglycolide, poly(lactide-co-glycolide), polyorthoester, polycaprolactone, polydioxanone polyalkylcarbonate, polyanhydride and copolymers thereof.

6 . The microparticle according to claim 1 , wherein the physiologically active peptide is present in an amount of 1.0 to 10% by weight with respect to the total weight of the microparticle.

7 . The microparticle according to claim 1 , wherein the content of the ionic complex is 4% by weight to 40% by weight, based on the total weight of the microparticle.

8 . A method for preparing physiologically active peptide-containing polymer complex comprising:

1) mixing a physiologically active peptide with an ionic water-soluble polymer in an aqueous medium to form an ionic complex of the physiologically active peptide and the water-soluble polymer; and

2) drying the ionic complex of the physiologically active peptide and the water-soluble polymer obtained in step 1).

9 . The method according to claim 8 , wherein the physiologically active peptide and the ionic water-soluble polymer is mixed with a mixing ratio of 1:1 to 10 as a molar ratio.

10 . A method for preparing physiologically active peptide-containing microparticle comprising:

a) homogeneously mixing an ionic complex of a physiologically active peptide and a water-soluble polymer with a biodegradable, water-insoluble polymer in a non-aqueous solvent; and

b) removing the non-aqueous solvent from the resulting solution obtained in step a) to obtain microparticle.

11 . The method according to claim 10 , wherein the non-aqueous solvent is selected from the group consisting of methylene chloride, ethyl acetate, chloroform, acetone, N-methyl-2-pyrrolidone, N,N-dimethylformamide, tetrahydrofuran, dimethyl sulfoxide, hexafluoroisopropanol and mixtures thereof.

12 . The method according to claim 10 , wherein step b) comprises:

b-1) filling a plurality of microwells placed in a water-soluble microtemplate with the solution obtained in step (a);

b-2) removing the non-aqueous solvent from the solution filled in the microwells to solidify the biodegradable, water-insoluble polymer; and

b-3) collecting microparticles from the microtemplate.

13 . The method according to claim 12 , wherein the water-soluble microtemplate is produced from one or more water-soluble polymers selected from gelatin, polyvinyl alcohol, agarose, poly(N-isopropyl acrylamide), alginate and mixtures thereof.

14 . The method according to claim 12 , wherein, in step b-3), the collection of microparticles is carried out by dissolving the microtemplate in an aqueous medium.

15 . The method according to claim 10 , wherein step b) comprises:

b-i) adding the resulting solution obtained in step a) dropwise to an aqueous solution of the water-soluble polymer in the presence of a surfactant with stirring to remove the non-aqueous solvent and obtain microparticle.

16 . A pharmaceutical composition comprising the microparticle containing physiologically active peptide according to claim 1 , and a pharmaceutically acceptable carrier.