JP2003252751A - New microsphere and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a microsphere having excellent dispersibility. <P>SOLUTION: The method for producing the microsphere having the improved dispersibility involves adding an osmotic pressure regulator to the outer water phase when producing the microsphere by drying method in water. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to microspheres having improved dispersibility, a method for producing the same, and a sustained-release composition containing the microspheres.

[0002]

2. Description of the Related Art A method for producing sustained-release microspheres from a W / O type emulsion using a biodegradable polymer is as follows.
For example, it is described in Patent Documents 1 to 3 and the like. Further, the biodegradable polymer having a sustained release property is useful as a base material for microspheres for encapsulating a physiologically active substance, for example. As such a biodegradable polymer,
It is known that polylactic acid, those containing a copolymer of lactic acid and glycolic acid, and the like (Patent Document 4, etc.) are useful.
As these biodegradable polymers, those produced by the conventional synthesis method were used as they were, but the synthesized ones as they were had little usefulness as a sustained-release base material due to the small amount of terminal carboxyl groups. I understand. Therefore, it was studied to use the biodegradable polymer having a high molecular weight as described above by hydrolysis to adjust the weight average molecular weight to an appropriate value, and then to use the biodegradable polymer as a base material for sustained-release preparations. However, the product obtained by hydrolysis treatment and water washing is not suitable as a sustained-release base material, even if it has an appropriate weight average molecular weight and terminal carboxyl group content, because it tends to cause initial burst. there were. Therefore, there is a current demand for improvement. Patent Document 5
Discloses a sustained-release preparation comprising a bioactive peptide or a salt thereof and a biodegradable polymer having a free carboxyl group at the end, and a method for producing the same. However, these documents do not describe a method for improving the dispersibility of microspheres.

[0003]

[Patent Document 1] JP-A-57-118512

[Patent Document 2] JP-A-57-150609

[Patent Document 3] Japanese Patent Laid-Open No. 6-145046

[Patent Document 4] Japanese Patent Laid-Open No. 11-269094

[Patent Document 5] Japanese Unexamined Patent Publication No. 7-97334

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide microspheres having improved dispersibility, a method for producing the same, and the like.

[0005]

Means for Solving the Problems As a result of intensive studies in view of the above problems, the present inventors have found that an osmotic pressure adjusting agent is present in an external water phase in a method for producing microspheres by an underwater drying method. Unexpectedly improved the dispersibility of the produced microspheres. The present inventors have completed the present invention as a result of further research based on these findings. That is, the present invention provides (1) when manufacturing microspheres by an underwater drying method,
A method for producing microspheres having improved dispersibility, which comprises adding an osmotic pressure adjusting agent to the external water phase; (2) 1.5 mL of microspheres having improved dispersibility of about 400 to about 700 mg. The production method according to (1) above, which can be dispersed in the dispersion medium for injection in less than 2 minutes;
(4) The production method according to (3) above, wherein the inner aqueous phase further contains a drug-retaining substance; (5) The production according to (1) above, wherein the O / W emulsion is used in the in-water drying method. Method; (6) Use of S / O / W type emulsion in water drying method (1)
(7) A W / O type emulsion in which a liquid containing a physiologically active substance or a salt thereof is used as an inner aqueous phase, and a solution containing a lactic acid polymer having a weight average molecular weight of 15,000 to 50,000 or a salt thereof is used as an oil phase. Is dispersed in an external water phase containing an osmotic pressure adjusting agent and subjected to an in-water drying method; (8) Weight average molecular weight of lactic acid polymer or salt thereof
The production method according to (7) above, wherein the polymer content of 5000 or less is about 10% by weight or less; (9) Weight average molecular weight of lactic acid polymer or salt thereof.
The production method according to (7) above, wherein the polymer content of 5000 or less is about 5% by weight or less; (10) The content of the polymer having a weight average molecular weight of 3000 or less in the lactic acid polymer or its salt is about 1.5% by weight. (11) The production method according to (7), wherein the content of the polymer having a weight average molecular weight of 1000 or less in the lactic acid polymer or a salt thereof is about 0.1% by weight or less. (12) The weight average molecular weight of the lactic acid polymer or its salt is 15
The production method according to (7) above, wherein the weight average molecular weight of the lactic acid polymer or its salt is 17
The production method according to (7) above, wherein the osmotic pressure adjusting agent is alcohols, sugars, amino acids, peptides, proteins, salts of water-soluble amino acids, or derivatives thereof, Is a mixture of these,
(15) The production method according to (1) or (7); (15) The production method according to (1) or (7), wherein the osmotic pressure adjusting agent is mannitol; (16) In the outer aqueous phase of the osmotic pressure adjusting agent. (17) The physiologically active substance according to the above (1) or (7), wherein the osmotic pressure of the external water phase is about 1/50 to about 5 times the osmotic pressure of physiological saline; The method according to (7) above, wherein is a water-soluble physiologically active substance; (18) The method according to (7), wherein the physiologically active substance is a physiologically active peptide; (19) The physiologically active substance is an LH-RH derivative. The above (7)
(20) The LH-RH derivative has the formula 5-oxo-Pro-His-Trp-Ser-Tyr-Y-Leu-Arg-Pro-Z [wherein Y is DLeu, DAla, DTrp, DSer. (tBu), D2Nal or
DHis (ImBzl) is shown, and Z is NH-C ₂ H ₅ or Gly-NH ₂ . ] The production method according to (7) above, which is a peptide or a salt thereof; (21) Microspheres obtained by the production method according to (1) or (7); (22) above (21) (23) Prostate cancer, prostatic hypertrophy, endometriosis, uterine fibroids, uterine fibroids, precocious puberty, dysmenorrhea or breast cancer. Alternatively, (22) The sustained-release composition for contraception; (24) The sustained-release composition according to (22), which is for injection; (25) The sustained-release composition according to (22), which further contains mannitol. (26) The sustained-release composition according to (22) above, which contains the microspheres in an amount of about 70% by weight or more based on the entire composition; Administering an effective amount of a sustained release composition Prostate cancer butterflies,
Prostatic hypertrophy, endometriosis, uterine fibroids, uterine fibroids, precocious puberty, dysmenorrhea or breast cancer prevention / treatment methods or contraceptive methods; (28) To produce microspheres with improved dispersibility In addition, when an emulsion containing a physiologically active substance or a salt thereof and a high molecular polymer is dried in water, an osmotic pressure adjusting agent is present in the outer aqueous phase, and (29) the dispersibility is improved. The present invention also provides the use of an osmotic pressure adjusting agent in the outer aqueous phase when an emulsion containing a physiologically active substance or a salt thereof and a high molecular polymer is dried in water for the production of microspheres. Further, the present invention provides (30) a physiologically active substance or a salt thereof and a weight average molecular weight of 5
Microspheres with improved dispersibility, characterized by containing a lactic acid polymer having a weight average molecular weight of 15,000 to 50,000 or a salt thereof having a polymer content of 000 or less of about 5% by weight or less; (31) About 400 to about 700 mg of the sustained release composition containing the microsphere according to (30) above is added to 1.5 m.
The microsphere according to (30) above, which is dispersed in a dispersion medium of L for less than 2 minutes; (32) The microsphere can be produced by allowing an osmotic pressure adjusting agent to be present in the outer aqueous phase during the production of the microsphere by an in-water drying method. (30) The microsphere according to (30); (33) The above-mentioned (32), wherein the underwater drying method is the W / O / W type.
(34) The sustained-release composition according to (32) above, wherein the underwater drying method is an O / W type; (35) the above-mentioned (32) wherein the underwater drying is an S / O / W type. (36) A liquid containing a physiologically active substance or a salt thereof is used as an inner aqueous phase, and the content of the polymer having a weight average molecular weight of 5000 or less is about 5;
Weight average molecular weight of 15,000 to 500, which is less than or equal to weight%.
The W / O type emulsion having a solution containing a lactic acid polymer of No. 00 or a salt thereof as an oil phase is dispersed in an aqueous phase containing an osmotic pressure adjusting agent and subjected to an in-water drying method to produce the above (30). (37) The microsphere according to (30), wherein the lactic acid polymer has a polymer content of a weight average molecular weight of 3000 or less of about 1.5% by weight or less; The microspheres according to (30) above, wherein the polymer content of the polymer having a weight average molecular weight of 1,000 or less is about 0.1% by weight or less; (39) The lactic acid polymer has a weight average molecular weight of 15,000 to 1,500.
The microsphere according to the above (30), which has a weight average molecular weight of 17,000 to 40,000.
The microsphere according to (30) above, which is 26000; (41) The microsphere according to (30), wherein the physiologically active substance is a water-soluble physiologically active substance; (42) The physiologically active substance is a physiologically active peptide. (43) The microsphere according to (41); (43) The physiologically active substance is an LH-RH derivative.
(44) The LH-RH derivative has the formula 5-oxo-Pro-His-Trp-Ser-Tyr-Y-Leu-Arg-Pro-Z (wherein Y is DLeu, DAla, DTrp). , DSer (tBu), D2Nal or
DHis (ImBzl) is shown, and Z is NH-C ₂ H ₅ or Gly-NH ₂ . ] The microsphere according to (43) above, which is a peptide represented by the following: (45) The concentration of the osmotic pressure adjusting agent in the outer phase is such that the osmotic pressure of the outer aqueous phase is about 1/50 of the osmotic pressure of physiological saline. The microspheres according to (32) to (36), wherein the osmotic pressure adjusting agent is alcohols, saccharides, amino acids, peptides, proteins, water-soluble amino acid salts, which is about 5 times as large as that of the above.
(32) to (36) above, which is a derivative thereof or a mixture thereof; (47) the microsphere according to (43), wherein the alcohol is a polyhydric alcohol or a monohydric alcohol; ) The microsphere according to the above (47), wherein the polyhydric alcohol is glycerin, arabitol, xylitol, adonitol, mannitol, sorbitol, dulcitol, or a mixture thereof; (49) The monohydric alcohol is methanol, ethanol,
(47) The microsphere according to (47) above, which is isopropyl alcohol or a mixture thereof. (50) The microsphere according to (46) above, wherein the saccharide is a monosaccharide, a disaccharide, an oligosaccharide or a derivative thereof, or a mixture thereof. ) The microsphere according to the above (50), wherein the monosaccharide is arabinose, xylose, ribose, 2-deoxyribose, glucose, fructose, galactose, mannose, sorbose, rhamnose or fucose; (52) The disaccharide is maltose, cellobiose, α (50) The microsphere according to (50) above, which is α-trehalose, lactose or sucrose; (53) The microsphere according to (50) above, wherein the oligosaccharide is maltotriose, raffinose sugar or stachyose; Induction of disaccharides or oligosaccharides Body glucosamine, galactosamine, above (50) is a glucuronic acid or galacturonic acid microspheres according; (55) amino acids are glycine, alanine, valine, leucine, isoleucine, phenylalanine, tyrosine,
(46) The microsphere according to the above (46), which is tryptophan, serine, threonine, proline, hydroxyproline, cysteine, methionine, aspartic acid, glutamic acid, lysine, arginine or histidine; (56) The water-soluble amino acid salt is glycine, alanine or valine , Leucine, isoleucine, phenylalanine, tyrosine, tryptophan, serine, threonine, proline, hydroxyproline, cysteine, methionine, aspartic acid, glutamic acid, lysine, arginine or histidine as a salt with an acid or an alkali metal, according to the above (46). Microspheres; (57) The above-mentioned (3), wherein the osmotic pressure adjusting agent is mannitol.
(58) The microsphere according to (30) above, which further contains a drug-holding substance; (59) The drug-holding substance is albumin, gelatin, salicylic acid, citric acid or sodium ethylenediaminetetraacetate. (60) The microsphere according to (58) above, wherein (60) the dispersion medium is a dispersant, a preservative, a tonicity agent or a vegetable oil. (61) Improving the dispersibility of the microsphere A method for producing microspheres with improved dispersibility, which comprises allowing an osmotic pressure adjusting agent to be present in the external water phase during the production of microspheres by the in-water drying method; (62) Physiological activity by the in-water drying method The weight average molecular weight of the substance or salt thereof and the polymer content of the weight average molecular weight of 5000 or less is about 5% by weight or less. 5,000 to 50,000
(63) A method for producing the microcapsules, characterized in that an osmotic pressure adjusting agent is present in the outer aqueous phase during the production of the microspheres containing the lactic acid polymer or a salt thereof; Above W type (62)
(64) The production method according to (62) above, wherein the underwater drying method is an O / W type; (65) The above-mentioned (62) production method, wherein the underwater drying is an S / O / W type; (66) A liquid containing a physiologically active substance or a salt thereof is used as an inner aqueous phase, and the content of a polymer having a weight average molecular weight of 5000 or less is about 5
Weight average molecular weight of 15,000 to 500, which is less than or equal to weight%.
No. 00 lactic acid polymer or a salt thereof is used as an oil phase to disperse a W / O type emulsion in an aqueous phase containing an osmotic pressure-adjusting agent, followed by an in-water drying method. The substance or a salt thereof and the weight average molecular weight of the polymer having a weight average molecular weight of 5,000 or less are about 5% by weight or less, and the weight average molecular weight is 150.
A method for producing microspheres containing from 0 to 50000 lactic acid polymer or a salt thereof; (67) The concentration of the osmotic pressure adjusting agent in the outer phase is such that the osmotic pressure of the outer aqueous phase is about 1 of the osmotic pressure of physiological saline. / 50 to about 5 times, the production method according to (66) above; (68) the production method according to (66) above, wherein the inner aqueous phase further contains a drug-retaining substance; (69) above (30) (70) Prostate cancer, prostatic hypertrophy, endometriosis, uterine fibroids, uterine fibroids, which comprises the microspheres according to (43) above. Sustained-release composition for prevention or treatment of precocious puberty, dysmenorrhea or breast cancer or sustained-release composition for contraception; (71) Sustained-release composition according to (69) or (70), which is for injection. (72) The above (() which further contains mannitol. 9) to
(71) The sustained-release composition according to (71); (73) About 70 microspheres based on the entire composition.
(69) to (72) The sustained release composition described in (69) to (72), which is contained in an amount of at least 50% by weight; (74) The microsphere described in (43) above, or a sustained release composition containing the same, to a mammal. Prostate cancer, prostatic hypertrophy, endometriosis, uterine fibroids, uterine fibroids, precocious puberty, dysmenorrhea or breast cancer, characterized by administering an effective amount of 75) A microsphere containing a physiologically active substance or a salt thereof and a high molecular polymer or a salt thereof, wherein about 400 to about 700 mg of the sustained-release composition containing the microsphere is dispersed in 1.5 mL of a dispersion medium. Long-term sustained-release microspheres that disperse in less than 2 minutes at room temperature; (76) The polymer or salt thereof has a weight average molecular weight of 1
Microspheres according to (75) above, which is a lactic acid polymer of 0000 to 50,000 or a salt thereof; (77) Sustained release composition containing the microspheres according to (75) or (76); (78) Drying in water In the method for producing microspheres containing a physiologically active substance or a salt thereof and a high molecular weight polymer by the method, a method for improving dispersibility of the microspheres, characterized in that an osmotic pressure adjusting agent is present in the outer aqueous phase. (79) Production of microcapsules by an in-water drying method for the purpose of improving the dispersibility of the microcapsules in an injectable composition containing microspheres containing a physiologically active substance or a salt thereof and a polymer. In the method, a microsphere in the injectable composition is characterized in that an osmotic pressure adjusting agent is present in the external aqueous phase. (80) A method for improving dispersibility; (80) For producing a microsphere having improved dispersibility in an injectable composition containing a microsphere containing a physiologically active substance or a salt thereof and a polymer, (81) A composition for injection containing microspheres containing a physiologically active substance or a salt thereof and a high molecular weight polymer, wherein an osmotic pressure adjusting agent is used in the outer aqueous phase in the method for producing the microcapsules by a drying method. The use of an osmotic pressure adjusting agent in the external aqueous phase in the method for producing the microcapsules by an in-water drying method, and (82) containing the osmotic adjusting agent for producing the microspheres having improved dispersibility in Disclosed is a microcapsule dispersibility-improving agent for use in the outer aqueous phase in an underwater drying method.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION As the physiologically active substance used in the present invention, those having a strong hydrophilicity and a small oil-water partition ratio between water and n-octanol are used. As the one having a small oil-water distribution ratio, for example, those having a ratio of n-octanol / water solubility of 1 or less are preferable, and those having a ratio of 0.1 or less are more preferable. The oil-water distribution ratio may be measured according to the method described in "Physical Chemistry Experimental Method" by Shinsaburo Samejima, published by Shokabo, 1936. That is, first, in the test tube, n-
Add octanol and pH 5.5 buffer (1: 1 equal mixture). Examples of the buffer solution include Sφerensen buffer solution [Ergeb. Physiol. 12, 3
93 (1912)], Clark-Lubs buffer [J. Bact. 2, (1), 109, 191 (191).
7)], Macllvaine buffer [J. Biol.
Chem. 49, 183 (1921)], Michaelis (Mic
haelis) buffer solution (Die Wasser-stoffionenkonzentratio
n, p.186 (1914)], Kolthoff buffer [Biochem. Z, 179, 410 (1926)] and the like. An appropriate amount of a drug is added to this, and the container is further capped and immersed in a constant temperature bath (25 ° C.), and often shaken vigorously.
Then, when it seems that the drug was dissolved between the two liquid layers and reached equilibrium, the liquid was allowed to stand or centrifuged, and a fixed amount of liquid was removed from each of the upper and lower layers with a pipette and analyzed to analyze each layer. If the concentration of the drug in the medium is determined and the ratio of the concentration of the drug in the n-octanol layer / the concentration of the drug in the water layer is taken,
It becomes the oil-water distribution rate.

The physiologically active substance is not particularly limited, but physiologically active substances, antitumor agents, antibiotics, antipyretics, analgesics, antiphlogistics, antitussive expectorants, sedatives, muscle relaxants, antiepileptic agents, antiulcers. Agents, antidepressants, antiallergic agents, cardiotonics,
Examples thereof include antiarrhythmic agents, vasodilators, antihypertensive diuretics, antidiabetic agents, anticoagulants, hemostatic agents, antituberculous agents, hormonal agents, opiate antagonists, bone resorption inhibitors, angiogenesis inhibitors, and the like. The physiologically active substance used in the present invention is not particularly limited as long as it is pharmacologically useful, but may be a non-peptide compound or a peptide compound. Examples of non-peptide compounds include agonists, antagonists, compounds having an enzyme inhibiting action, and the like. As the peptide compound, for example, a physiologically active peptide is preferable, and the molecular weight is about 300 to about 40,000, preferably about 400 to about 30,000, and more preferably about 500 to about 20,0.
Examples of the physiologically active peptide of which No. 00 is suitable include, for example, luteinizing hormone-releasing hormone (LH-RH), insulin, somatostatin, growth hormone, growth hormone-releasing hormone (GH-RH), prolactin, erythro. Poietin, adrenocortical hormone,
Melanocyte stimulating hormone, thyroid hormone releasing hormone (TRH), thyroid stimulating hormone, luteinizing hormone, follicle stimulating hormone, vasopressin, oxytocin,
Calcitonin, gastrin, secretin, pancreosymine, cholecystokinin, angiotensin, human placental lactogen, human chorionic gonadotropin, enkephalin, endorphin, kyotorphin, tuftsin, thymopoietin, thymosin, thymotimulin,
Thymic humoral factor, blood thymic factor, tumor necrosis factor, colony-inducing factor, motilin, deinorphin, bombesin, neurotensin, cerulein, bradykinin, atrial natriuretic factor, nerve growth factor, cell growth factor,
Examples thereof include neurotrophic factors, peptides having endothelin antagonism and derivatives thereof, and fragments or derivatives of these fragments.

A preferred example of the physiologically active peptide is a LH-RH derivative, which is a hormone-dependent disease,
Especially sex hormone-dependent cancer (eg, prostate cancer, uterine cancer, breast cancer, pituitary tumor, etc.), benign prostatic hyperplasia, endometriosis, uterine fibroids, precocious puberty, dysmenorrhea, amenorrhea, premenstrual LH-RH derivative or its salt effective in sex hormone-dependent diseases such as syndrome, multilocular ovary syndrome and contraception (or infertility when the rebound effect after withdrawal thereof is used) . Furthermore, LH-RH derivatives or salts thereof that are effective for benign or malignant tumors that are sex hormone independent but LH-RH sensitive are also included. Specific examples of the LH-RH derivative or a salt thereof include:
For example, Treatment With GnRH Analog:
Contravers and Perspective (Treatm
ent with GnRH analogs: Controversies and perspecti
ves) [Parthenon Publishing Group Co., Ltd.
(The Parthenon Publishing Group Ltd.) Published 1996
Year], Japanese Patent Laid-Open No. 3-503165, Japanese Patent Laid-Open No. 3-10
No. 1695, No. 7-97334 and No. 8-2594.
Examples thereof include peptides described in JP-A-60.

Examples of the LH-RH derivative include LH-RH agonists and LH-RH antagonists. Examples of the LH-RH antagonists include, for example, the general formula [I] X-D2Nal-D4ClPhe-D3Pal-Ser-AB- Leu-C-Pro-DAlaNH ₂ [wherein X is N (4H ₂ -furoyl) Gly or NAc and A is NMeTy
r, Tyr, Aph (Atz), the residue selected from NMeAph (Atz),
B is DLys (Nic), DCit, DLys (AzaglyNic), DLys (AzaglyF
ur), DhArg (Et ₂ ), DAph (Atz) and DhCi, and C is Lys (Nisp), Arg or hArg (Et ₂ ), respectively. Is used. Examples of the LH-RH agonist include, for example, the general formula [II] 5-oxo-Pro-His-Trp-Ser-Tyr-Y-Leu-Arg-Pro-Z [wherein Y is DLeu, DAla, DTrp, DSer. (tBu), D2Nal and DHis (ImBzl), a Z is NH—C ₂ H ₅ or
Gly-NH ₂ respectively] or a physiologically active peptide represented by the formula] is used. In particular, Y is DLeu,
Peptides where Z is NH-C ₂ H ₅ (ie 5-oxo-Pro-His-Trp
-Ser-Tyr-DLeu-Leu-Arg-Pro-NH-C ₂ H ₅ Peptide A; Leuprorelin) or salts thereof (eg acetate)
Is preferred. These peptides can be produced by the methods described in the above-mentioned documents or gazettes or by methods similar thereto.

The abbreviations used in the present specification have the following meanings. Abbreviation Name N (4H ₂ -furoyl) Gly: N-tetrahydrofuroylglycine residue NAc: N-acetyl group D2Nal: D-3- (2-naphthyl) alanine residue D4ClPhe: D-3- (4-chloro) Phenylalanine residue D3Pal: D-3- (3-pyridyl) alanine residue NMeTyr: N-methyltyrosine residue Aph (Atz): N- [5 '-(3'-amino-1'H-1', 2 ', 4'-Triazolyl)] phenyl alanine residue NMeAph (Atz): N-methyl- [5'-(3'-amino-1'H-1 ', 2', 4'-triazolyl)] phenylalanine residue DLys (Nic): D- (eN-nicotinoyl) lysine residue Dcit: D-citrulline residue DLys (AzaglyNic): D- (azaglycylnicotinoyl) lysine residue DLys (AzaglyFur): D- (azaglycylfura) Nyl) lysine residue DhArg (Et ₂ ): D- (N, N'-diethyl) homoarginine residue DAph (Atz): DN- [5 '-(3'-amino-1'H-1', 2 ', 4'-Triazolyl)] Phenylalanine residue DhCi: D-homocitrulline residue Lys (Nisp): (eN-isopropyl) lysine residue hArg (Et ₂ ): (N, N'-diethyl) homoarginine residue and other amino acids, IUPAC-IU
B Commission of Biochemical Nomenclature
(European Journal of Biochemistry, Vol. 138, 9
~ 37 (1984)) or conventional abbreviations in the relevant field, and where amino acids may have optical isomers, L form is shown unless otherwise specified.

As a peptide having physiological activity,
Are LH-RH antagonists (US Pat. No. 4,086,219).
Issue No. 4,124,577, No. 4,253,997
No., No. 4,317,815). Well
Moreover, as a peptide having further physiological activity,
For example, insulin, somatostatin, somatostatin derivative
(U.S. Patent Nos. 4,087,390 and 4,093,57
No. 4, No. 4,100, 117, No. 4,253, 998
Issue), growth hormone, prolactin, adrenocortical stimulation
Hormone (ACTH), melanocyte-stimulating hormone (M
SH), thyroid hormone releasing hormone [(Pyr) Glu-His-P
roNH ₂ It is represented by the structural formula of and is abbreviated as TRH below.
There is also a salt and a derivative thereof (JP-A-50-121).
No. 273, Japanese Patent Application Laid-Open No. 52-116465), A
Gonadotropin (TSH), luteinizing hormone (L
H), follicle stimulating hormone (FSH), vasopressin, ba
Sopressin derivative {desmopressin [Japan Society of Endocrinology
Magazine, Vol. 54, No. 5, pp. 676-691 (1978)]
}}, Oxytocin, Calcitonin, Parathyroid formo
, Glucagon, gastrin, secretin, pancreo
Zymin, Cholecystokinin, Angiotensin, Human
Placental lactogen, human chorionic gonadotropin (HC
G), enkephalin, enkephalin derivatives [US special
Xu 4,277,394, European Patent Publication No. 3
No. 1567], Endorphin, Kyotoruf
In, interferons (eg, α type, β type, γ type
Etc.), interleukins (eg, I, II, III, etc.),
Futsin, thymopoietin, thymosin, thymosti
Murin, thymic humoral factor (THF), blood thymic factor (FT)
S) and its derivatives (US Pat. No. 4,229,438)
), And other thymic factors [medical history, 1st
25, No. 10, pp. 835-843 (1983)],
Tumor necrosis factor (TNF), colony inducing factor (CS
F), motilin, dynorphin, bombesin, new
Rotensin, cerulein, bradykinin, urokiner
Ze, asparaginase, kallikrein, substance
P, nerve growth factor, cell growth factor, neurotrophic factor, blood
Coagulation factors VIII, IX, lysozyme chloride, po
Limixin B, colistin, gramicidin, bacitraci
And erythropoietin (EPO), endothelin antagonism
Peptides having action (European Patent Publication No. 436
No. 189, No. 457195, No. 4964452,
See Japanese Patent Application Laid-Open Nos. 3-94692 and 3-130299.
Teru) and the like.

The above antitumor agents include bleomycin,
Methotrexate, actinomycin D, mitomycin C, vinblastine sulfate, vincristine sulfate, daunorubicin, adriamycin, neocarzinostatin, cytosine arabinoside, fluorouracil, tetrahydrofuryl-5-fluorouracil, crestin, picibanil, lentinan, levamisole, bestatin,
Azimexone, Glycyrrhizin, Poly I: C, Poly A:
U, poly ICLC and the like. Examples of the above-mentioned antibiotics include gentamicin, dibekacin, canendomycin, ribidomycin, tobramycin, amikacin, fradiomycin, sisomycin, tetracycline hydrochloride, oxytetracycline hydrochloride, loritetracycline, doxycycline hydrochloride, ampicillin, piperacillin, ticarcillin, cephalothin, cephaloridine. , Cefotiam, cefthrozine, cefmenoxime, cefmetazole, cefazoline, cefotaxime, cefoperazone, ceftizoxime, moxalactam, thienamycin, sulfazecin, aztreonam, etc. Examples of the above antipyretic, analgesic and anti-inflammatory agents include salicylic acid, sulpirine, flufenamic acid, diclofenac,
Examples include indomethacin, morphine, pethidine hydrochloride, levorphanol tartrate, and oxymorphone. Antitussive expectorants include ephedrine hydrochloride, methylephedrine hydrochloride, noscapine hydrochloride, codeine phosphate, dihydrocodeine phosphate, alloclamide hydrochloride, clofedanol hydrochloride, picoperidamine hydrochloride, cloperastine, protoxylol hydrochloride, isoproterenol hydrochloride, salbutamol sulfate, Examples thereof include terbutaline sulfate. Examples of the sedatives include chlorpromazine, prochlorperazine, trifluoperazine, atropine sulfate, and methylscopolamine bromide. Examples of the muscle relaxant include pridinol methanesulfonate, tubocurarine chloride, pancuronium bromide and the like. Antiepileptic agents include phenytoin, ethosuximide, sodium acetazolamide,
Examples include chlordiazepoxide. Examples of anti-ulcer agents include metoclopromide, histidine hydrochloride and the like. Examples of the antidepressant include imipramine, clomipramine, noxiptiline, phenelzine sulfate and the like. Examples of antiallergic agents include diphenhydramine hydrochloride, chlorpheniramine maleate, tripelenamine hydrochloride, metzirazine hydrochloride, clemizole hydrochloride, diphenylpyraline hydrochloride and methoxyphenamine hydrochloride.

Examples of the cardiotonic agent include transpyoxocamphor, theophyllol, aminophylline, etilefrine hydrochloride and the like. Examples of antiarrhythmic agents include propranol, alprenolol, bufetrol, oxyprenolol and the like. Examples of the vasodilator include oxyfedrine hydrochloride, diltiazem, tolazoline hydrochloride, hexobendine, bamethane sulfate and the like. As antihypertensive diuretics, hexamethonium bromide,
Examples include pentolinium, mecamylamine hydrochloride, ecarazine hydrochloride, and clonidine. Examples of the antidiabetic agent include glymidine sodium, glipizide, phenformin hydrochloride, buformin hydrochloride, metformin and the like. As anticoagulants, heparin sodium,
Examples include sodium citrate. Examples of the hemostatic include thromboplastin, thrombin, menadione sodium bisulfite, acetomenaphthone, ε-aminocaproic acid, tranexamic acid, sodium carbazochrome sulfonate, and adrenochrome monoaminoguanidine methanesulfonate. Examples of antituberculous agents include isoniazid, ethambutol, para-aminosalicylic acid and the like. Examples of the hormonal agents include prednisolone, sodium prednisolone phosphate, dexamethasone sodium sulfate, betamethasone sodium phosphate, hexestrol phosphate phosphate, hexestrol acetate acetate, and methimazole. Examples of narcotic antagonists include levallorphan tartrate, nalorphine hydrochloride, naloxone hydrochloride and the like. Examples of the bone resorption inhibitor include (sulfur-containing alkyl) aminomethylenebisphosphonic acid. Examples of angiogenesis inhibitors include angiogenesis inhibitor steroids [Science, Vol. 221, p. 719 (19
1983)], Fumagillin (European Patent Publication No. 3
25199), fumagillol derivatives (European Patent Publication Nos. 357061 and 359036,
Nos. 386667 and 415294).

The physiologically active substance itself used in the present invention may be a pharmacologically acceptable salt.
Examples of such salts include inorganic acids (also called inorganic free acids) (eg, carbonic acid, bicarbonate, hydrochloric acid, sulfuric acid, nitric acid, boric acid, etc.) when the physiologically active substance has a basic group such as an amino group. ), An organic acid (also referred to as an organic free acid) (eg, succinic acid, acetic acid, propionic acid, trifluoroacetic acid, etc.) and the like. When the physiologically active substance has an acidic group such as a carboxyl group, an inorganic base (also referred to as an inorganic free base) (eg, an alkali metal such as sodium or potassium,
Alkaline earth metals such as calcium and magnesium)
And salts with organic bases (also referred to as organic free bases) (eg, organic amines such as triethylamine, basic amino acids such as arginine). In addition, physiologically active peptides are metal complex compounds (eg, copper complex, zinc complex, etc.)
May be formed.

The high molecular weight polymer used in the present invention is a high molecular weight polymer which is hardly soluble or insoluble in water and is biocompatible (biodegradable). Poorly soluble in water means that the polymer has a solubility in water of more than 0 and about 3% or less, and more preferably a solubility of water of more than 0 and about 1% (W / W) or less. . These biodegradable polymers have a weight average molecular weight of about 10,000 to 50,000, preferably about 15,000 to 5,000.
0, more preferably about 15,000 to 40,000, and particularly preferably about 17,000 to 26,000 is used. The biodegradable polymer has a dispersity of about 1.
2 to 4.0, especially about 1.5 to 3.5 are preferred.
The weight average molecular weight and polydispersity used in this specification are determined by gel permeation chromatography (GPC: Gel Perm).
eation Chromatography). The amount of these high molecular weight polymers used depends on the strength of the pharmacological activity of the physiologically active substance or its salt, and the rate and period of release of the physiologically active substance or its salt. It is prepared in an amount of 0.5 to 10,000 times (weight ratio), preferably about 1 to 10
It is preferable to use 0 times (weight ratio) of the polymer as the microsphere base. As such a high molecular weight polymer, for example, a biodegradable high molecular weight polymer is preferable, and for example, an aliphatic polyester [for example, α-hydroxy acid (eg,
Glycolic acid, lactic acid, 2-hydroxybutyric acid, 2-hydroxyvaleric acid, 2-hydroxy-3-methylbutyric acid, 2-hydroxycaproic acid, 2-hydroxyisocaproic acid,
2-hydroxycaprylic acid, etc.), α-hydroxy acid cyclic dimers (eg, glycolide, lactide, etc.), hydroxydicarboxylic acids (eg, malic acid), hydroxytricarboxylic acid (eg, citric acid), etc. Polymers (eg, lactic acid polymers, etc.) or copolymers of two or more types (eg, lactic acid / glycolic acid copolymers, 2-hydroxybutyric acid / glycolic acid copolymers, etc.), or homopolymers and / or copolymers thereof. Polymer mixture (eg, mixture of lactic acid polymer and 2-hydroxybutyric acid / glycolic acid copolymer)], poly-α-cyanoacrylic acid ester, polyamino acid (eg,
Poly-γ-benzyl-L-glutamic acid, poly-L-alanine, poly-γ-methyl-L-glutamic acid, etc.), maleic anhydride copolymers (eg, styrene / maleic acid copolymers, etc.) and the like. To be Of these, aliphatic polyester and poly-α-cyanoacrylic acid ester are preferable. Furthermore, aliphatic polyesters are particularly preferred.

Among the aliphatic polyesters, homopolymers of α-hydroxy acids and α-hydroxy acid cyclic dimers,
Alternatively, two or more kinds of copolymers, or a mixture of these homopolymers and / or copolymers are preferable. further,
Homo- or copolymers of α-hydroxy acids, or mixtures of these homo- and / or copolymers are particularly preferred. When the α-hydroxy acid, the cyclic dimer of α-hydroxy acid, the hydroxydicarboxylic acid, and the hydroxytricarboxylic acid have an optically active center in the molecule, any of the D-, L-, and DL-forms may be used. it can. The aliphatic polyester can be produced without problems by a known production method (see, for example, JP-A-61-28521). In addition, the type of polymerization is random, block,
Either graft may be used. The weight average molecular weight of the aliphatic polyester is about 10,000 to 50,000, preferably about 15,000 to 50,000, and more preferably about 15.
000 to 40,000, particularly preferably about 17,000 to 26,000. The dispersity of the aliphatic polyester is preferably about 1.2 to 4.0, particularly preferably about 1.5 to 3.5.

When a lactic acid / glycolic acid copolymer is used as the aliphatic polyester, the composition ratio is about 10
0/0 to about 50/50 (weight ratio) is preferable, and when a 2-hydroxybutyric acid / glycolic acid copolymer is used, its composition ratio is preferably about 100/0 to about 25/75 (weight ratio). Lactic acid polymer, lactic acid / glycolic acid copolymer, 2-
The weight average molecular weight of the hydroxybutyric acid / glycolic acid copolymer is preferably about 15,000 to 50,000, more preferably about 15,000 to 40,000. When a mixture of lactic acid polymer (A) and glycolic acid / 2-hydroxybutyric acid copolymer (B) is used as the aliphatic polyester, the mixing ratio represented by (A) / (B) is about 10 /. 90 to about 90/10 (weight ratio)
Used in the range of. Preferably about 25/75 to about 7
It is in the range of 5/25 (weight ratio). The weight average molecular weight of the lactic acid polymer is preferably about 15,000 to 50,000, and more preferably about 15,000 to 40,000. The glycolic acid / 2-hydroxybutyric acid copolymer has a composition of about 40 to 70 mol of glycolic acid,
Those in which the balance is 2-hydroxybutyric acid are preferred. The weight average molecular weight of the glycolic acid / 2-hydroxybutyric acid copolymer is preferably about 15,000 to 50,000, more preferably about 15,000 to 40,000.

Among them, the high molecular weight polymer used in the present invention is preferably a lactic acid polymer (hereinafter sometimes abbreviated as the lactic acid polymer of the present invention). For example, a polymer composed of lactic acid alone or lactic acid And a copolymer of other monomer (eg, glycolic acid), the content of the polymer having a weight average molecular weight of 5000 or less is usually about 10% by weight or less, preferably the polymer content of a weight average molecular weight of 5000 or less is usually contained. Up to about 5% by weight, more preferably a weight average molecular weight of 3
000 or less polymer content about 1.5 wt% or less, more preferably weight average molecular weight 1000 or less polymer content about 0.1 wt% or less, even more preferably polymer with weight average molecular weight 5000 or less. A content of about 5% by weight or less and a weight average molecular weight of 3,000 or less is about 1.5% by weight or less, and most preferably a weight average molecular weight of 5,000 or less is about 5% by weight or less. Polymer content of weight average molecular weight 3,000 or less is about 1.5% by weight
The following is used and the content of the polymer having a weight average molecular weight of 1,000 or less is about 0.1% by weight or less. Also,
The weight average molecular weight of the lactic acid polymer of the present invention is usually 15,000.
-50000, preferably 15000-400000, more preferably 17000-26000, particularly preferably 17500-25500.

The high-molecular-weight lactic acid polymer used as a raw material for the lactic acid polymer of the present invention may be a commercially available product or a polymerized by a known method, and its weight average molecular weight is usually 15,000 to 50.
It is 0000, preferably 20,000 to 100,000. Known polymerization methods include, for example, a method of condensation-polymerizing lactic acid and optionally glycolic acid, such as lactide, optionally together with glycolide, for example, diethyl zinc, triethylaluminum, a Lewis acid such as tin octylate or a metal salt. A method of ring-opening polymerization using a catalyst such as
A method of ring-opening polymerization of lactide in the presence of a hydroxycarboxylic acid derivative in which a carboxyl group is protected (for example, Patent International Publication WO00 / 35990 etc.), or ring-opening polymerization by adding a catalyst to lactide under heating. (For example, J. Med. Chem, 16, 897 (1973)), for example, a method of copolymerizing lactide and glycolide, and the like. Examples of the polymerization form include bulk polymerization in which lactide or the like is melted and subjected to the polymerization reaction, and solution polymerization in which lactide or the like is dissolved in a suitable solvent and subjected to the polymerization reaction. From the viewpoint of industrial production, it is preferable to use it as a raw material for the lactic acid polymer. Examples of the solvent that dissolves lactide in solution polymerization include aromatic hydrocarbons such as benzene, toluene, xylene, decalin, dimethylformamide, and the like.

To hydrolyze the high-molecular-weight lactic acid polymer obtained as described above, a hydrolysis method known per se is used. For example, after dissolving the high-molecular-weight lactic acid polymer in a suitable solvent, , Water and, if necessary, an acid may be added and reacted. The solvent that dissolves the high-molecular-weight lactic acid polymer may be any solvent that can dissolve the lactic acid polymer in an amount of 10 times or less the weight of the lactic acid polymer. Specifically, for example, chloroform,
Examples thereof include halogenated hydrocarbons such as dichloromethane, aromatic hydrocarbons such as toluene, o-xylene, m-xylene and p-xylene, cyclic ethers such as tetrahydrofuran, acetone and N, N-dimethylformamide. Incidentally, at the time of polymerizing the high-molecular-weight lactic acid polymer, when a solvent that can be used for hydrolysis of the high-molecular-weight lactic acid polymer is used, the polymerized high-molecular-weight lactic acid polymer is not isolated,
The operations of polymerization and hydrolysis can be carried out continuously.
The amount of the solvent that dissolves the high molecular weight lactic acid polymer is usually 0.1 to 100 times, preferably 1 to 10 times the lactic acid polymer as a solute. The amount of water to be added is usually 0.001 to 1 times, preferably 0.01 to 0.1 times the weight of the high molecular weight lactic acid polymer. Examples of the acid to be added as necessary include inorganic acids such as hydrochloric acid, sulfuric acid and nitric acid, and organic acids such as lactic acid, acetic acid and trifluoroacetic acid, and preferably lactic acid. The amount of acid added is usually 0 to 10 times the weight of the high molecular weight lactic acid polymer,
The hydrolysis reaction temperature, which is preferably 0.1 to 1 times the weight, is generally 0 to 150 ° C, preferably 20 to 80 ° C. The hydrolysis reaction time varies depending on the weight average molecular weight of the high molecular weight lactic acid polymer and the reaction temperature, and is usually 10 minutes to 100 hours, preferably 1 to 20 hours. The end time of the hydrolysis treatment is judged based on the weight average molecular weight of the hydrolysis product. That is, sampling is appropriately performed during the hydrolysis treatment, and the weight average molecular weight of the hydrolysis product in the sample is measured by gel permeation chromatography (GPC).
When it is confirmed that it is 50,000, preferably about 15,000 to 30,000, more preferably about 17,000 to 26,000, and particularly preferably 17500 to 25500, the hydrolysis treatment is stopped.

As a method for precipitating the desired lactic acid polymer contained therein from the solution containing the hydrolysis product obtained by subjecting the high-molecular-weight lactic acid polymer to hydrolysis , A method of bringing the solution containing the hydrolysis product into contact with a solvent capable of precipitating the desired lactic acid polymer contained therein, and the like. As a preferred embodiment of the solution containing the hydrolysis product, halogenated hydrocarbons such as chloroform and dichloromethane, aromatic hydrocarbons such as toluene, o-xylene, m-xylene and p-xylene, cyclic ethers such as tetrahydrofuran. , Acetone, N, N-dimethylformamide, etc., in a solvent in which a high molecular weight lactic acid polymer such as dichloromethane or xylene is dissolved, in a solvent having a weight average molecular weight of 15000-5000.
0, preferably 15000 to 30000, more preferably 17000 to 26000, particularly preferably 17500.
-25500 lactic acid polymer is dissolved in about 10 to 50 wt%. Examples of the solvent capable of precipitating the desired lactic acid polymer contained in the hydrolysis product-containing solution include alcohols such as methanol and ethanol, chain ethers such as isopropyl ether, and the like.
Examples thereof include aliphatic hydrocarbons such as hexane, water and the like.

The amount of the solvent capable of precipitating the desired lactic acid polymer is usually 0.1 to 100 times, preferably 1 to 10 times the weight of the solvent of the hydrolysis product-containing solution. As a preferred specific example of such a combination of the type and the amount of each solvent used, for example, in a hydrolysis product-containing solution in which 1 to 5 times by weight of dichloromethane is used as a solvent, a solvent for decreasing the solubility is used. Examples include a mode in which isopropyl ether is used in an amount of 2 to 10 times by weight with respect to the dichloromethane. When the solvent capable of precipitating the target lactic acid polymer solute is brought into contact with the hydrolysis product-containing solution, the temperature of the solvent is usually −20 to 60 ° C., preferably 0 to 40 ° C. The temperature of the solution is usually 0 to 40 ° C, preferably 10 to 30 ° C.
As a method of contacting the solvent and the hydrolysis product-containing solution, a method of adding the hydrolysis product-containing solution to the solvent at once, a method of dropping the hydrolysis product-containing solution into the solvent, and a method of hydrolyzing the solvent And a method of adding a solvent dropwise to the hydrolysis product-containing solution. The lactic acid polymer of the present invention obtained as described above is preferable as a base material for sustained-release preparations because the amount of terminal carboxyl groups is within the range preferable for the base material for sustained-release preparations. Further, as the biocompatible high molecular weight polymer, for example, polystyrene, polymethacrylic acid, a copolymer of acrylic acid and methacrylic acid,
Polyamino acid, dextrans tearate, ethyl cellulose, acetyl cellulose, nitrocellulose, maleic anhydride copolymer, ethylene vinyl acetate copolymer, polyvinyl acetate, polyacrylamide and the like are used. These high molecular polymers may be one kind, two or more kinds of copolymers or a simple mixture, or a salt thereof. The concentration of the high molecular weight polymer in the oil phase is about 0.5 to about 90% (W / W), more preferably about 2 to about 60% (W / W).

Examples of the drug holding substance used in the present invention include albumin, gelatin, citric acid, salicylic acid, sodium ethylenediaminetetraacetate, dextrin, sodium bisulfite, polyol compounds such as polyethylene glycol, agar, alginic acid, polyvinyl alcohol, and the like. Basic amino acids and the like are used.

The microspheres of the present invention are produced by an underwater drying method, preferably a (W / O) / W type underwater drying method, an O / W type underwater drying method or an S / O / W type underwater drying method. be able to. In the case of the (W / O) / W type underwater drying method, a liquid containing a physiologically active substance or a salt thereof is used as an inner aqueous phase,
A solution containing a high-molecular polymer is used as an oil phase to prepare a W / O type emulsion, and the emulsion is dispersed in an aqueous phase containing an osmotic pressure adjusting agent to form a (W / O) / W type emulsion, By subjecting to a drying method and removing the solvent in the oil phase, microspheres containing a physiologically active substance or a salt thereof and a high molecular polymer can be produced. In the case of the O / W type in-water drying method, an oil phase composed of a physiologically active substance or a salt thereof and a high molecular weight polymer is dispersed in an aqueous phase containing an osmotic pressure adjusting agent so that
A microsphere containing a physiologically active substance or a salt thereof and a high molecular weight polymer is produced by preparing a / W type emulsion and subjecting it to an underwater drying method to remove the solvent in the oil phase.
In the case of the S / O / W type in-water drying method, a physiologically active substance or a salt thereof is dispersed in an oil phase which is a solution containing a high molecular weight polymer, and this is dispersed in an aqueous phase containing an osmotic pressure adjusting agent. / O /
A W-type emulsion is prepared and subjected to an in-water drying method, and the solvent in the oil phase is removed to produce microspheres containing a physiologically active substance or a salt thereof and a polymer.

The osmotic pressure adjusting agent used in the present invention may be any substance as long as it exhibits an osmotic pressure when made into an aqueous solution. Examples of the osmotic pressure regulator include alcohols such as polyhydric alcohols and monohydric alcohols; saccharides such as monosaccharides, disaccharides and oligosaccharides; water-soluble amino acids, peptides, proteins; A salt; or a derivative thereof or the like is used. Examples of the above polyhydric alcohols include trihydric alcohols such as glycerin, pentahydric alcohols such as arabitol, xylitol and adonitol, and hexahydric alcohols such as mannitol, sorbitol and dulcitol. Of these, hexahydric alcohols are preferable, and mannitol is particularly preferable. Examples of the above-mentioned monohydric alcohols include methanol, ethanol, isopropyl alcohol and the like, among which ethanol is preferable. Examples of the above-mentioned monosaccharides include pentacarbon sugars such as arabinose, xylose, ribose and 2-deoxyribose, and hexacarbon sugars such as glucose, fructose, galactose, mannose, sorbose, rhamnose and fucose. Carbohydrates are preferred. As the above disaccharide, maltose, cellobiose, α, α-trehalose, lactose, sucrose and the like are used. Of these, lactose and sucrose are preferable. Examples of the above oligosaccharides include trisaccharides such as maltotriose and raffinose sugar, and tetrasaccharides such as stachyose. Of these, trisaccharides are preferable. As the above-mentioned monosaccharide, disaccharide and oligosaccharide derivatives, for example, glucosamine, galactosamine, glucuronic acid, galacturonic acid and the like are used.

As the above-mentioned amino acids, any of L-forms can be used, and for example, glycine, alanine, valine, leucine, isoleucine, phenylalanine, tyrosine, tryptophan, serine, threonine, proline, hydroxy. Neutral amino acids such as proline, cysteine and methionine; acidic amino acids such as aspartic acid and glutamic acid; basic amino acids such as lysine, arginine and histidine are used. Among them, glycine, leucine, arginine and the like are preferably used, and L-arginine is particularly preferable. In addition, salts of these water-soluble amino acids, for example, salts of water-soluble amino acids with acids (eg, hydrochloric acid, sulfuric acid, phosphoric acid, etc.) or alkalis (eg, alkali metals such as sodium, potassium, etc.) may be used. Examples of water-soluble peptides, proteins or their derivatives include casein, globulin, prolamin, albumin, gelatin and the like. These osmotic pressure regulators may be used alone or in a mixture.

The amount of the physiologically active substance or its salt used varies depending on the type of drug, desired pharmacological effect and duration of effect, but the concentration in the inner aqueous phase is about 0.001.
% To about 90% (W / W), more preferably about 0.01%
To about 80% (W / W), particularly preferably about 0.0
1% to about 70% (W / W). The osmotic pressure adjusting agent has an osmotic pressure of the outer aqueous phase of about 1/50 to about 5 of the osmotic pressure of physiological saline.
The concentration is doubled, preferably about 1/25 to about 3 times, more preferably about 1/12 to about 2 times. Specifically, the concentration of the osmotic pressure adjusting agent in the outer aqueous phase is about 0.01% to about 60% (W / W) when the osmotic pressure adjusting agent is a nonionic substance.
W), preferably about 0.01 to about 40% (W / W), more preferably about 0.05 to about 30% (W / W), and particularly preferably about 0.5 to about 1.5% ( W / W). When the osmotic pressure adjusting agent is an ionic substance, a concentration obtained by dividing the above concentration by the total ionic value is used. The added concentration of the osmotic pressure adjusting agent does not have to be the solubility or less, and a part thereof may be in a dispersed state. In the present invention, by adding an osmotic pressure adjusting agent to the external water phase, it is possible to improve the dispersibility of the produced microspheres, the degree is not particularly limited, for example, about 400 to 700 mg of microspheres. Is preferably dispersed in 1.5 mL of the dispersion medium for injection in less than 2 minutes.

The method for producing microspheres by the (W / O) / W type underwater drying method of the present invention will be described below. During the following production steps, the following may be added to the inner aqueous phase, if necessary. (1) Drug retaining agent Albumin, gelatin, citric acid, salicylic acid, sodium ethylenediaminetetraacetate, dextrin, sodium bisulfite, polyol compounds such as polyethylene glycol, agar, alginic acid, polyvinyl alcohol,
Basic amino acids, etc. (2) pH adjuster for maintaining stability and solubility of physiologically active substance or salt thereof Carbonic acid, acetic acid, oxalic acid, citric acid, phosphoric acid, hydrochloric acid, sodium hydroxide, arginine, lysine and salts thereof. (3) Stabilizers for physiologically active substances or salts thereof Polyol compounds such as albumin, gelatin, citric acid, sodium ethylenediaminetetraacetate, dextrin, sodium bisulfite and polyethylene glycol. (4) Preservatives Paraoxybenzoic acid esters (methylparaben, propylparaben, etc.), benzyl alcohol, chlorobutanol, thimerosal, etc.

(I) O / W Method In this method, first, an organic solvent solution of a polymer is prepared. The organic solvent used in the production of the microspheres of the present invention preferably has a boiling point of 120 ° C or lower. Examples of the organic solvent include halogenated hydrocarbons (eg, dichloromethane, chloroform, dichloroethane, trichloroethane, carbon tetrachloride, etc.), ethers (eg, ethyl ether, isopropyl ether, etc.), fatty acid esters (eg, ethyl acetate, Butyl acetate, etc.), aromatic hydrocarbons (eg, benzene, toluene, xylene, etc.),
Alcohols (eg ethanol, methanol, etc.),
Acetonitrile or the like is used. Of these, halogenated hydrocarbons are preferable, and dichloromethane is particularly preferable. Further, these may be mixed and used at an appropriate ratio. In that case, a mixed liquid of a halogenated hydrocarbon and alcohols is preferable, and a mixed liquid of dichloromethane and ethanol is particularly preferable. The concentration of the high molecular weight polymer in the organic solvent solution varies depending on the molecular weight of the high molecular weight polymer and the type of the organic solvent. For example, when dichloromethane is used as the organic solvent, it is generally about 0.5 to about 70. % By weight, more preferably from about 1 to about 60% by weight, particularly preferably from about 2
It is selected from about 50% by weight. When ethanol is used as a mixed organic solvent with dichloromethane, the ratio of both is generally about 0.01 to about 50% (v / v), more preferably about 0.05 to about 40% ( v / v), particularly preferably about 0.
It is selected from 1 to about 30% (v / v). A physiologically active substance or a salt thereof is added to an organic solvent solution of the high molecular weight polymer thus obtained, and dissolved or dispersed. At this time, the upper limit of the weight ratio of the physiologically active substance or its salt: high molecular polymer is about 1: 1.
It should be up to 1, preferably up to about 1: 2.

Then, an organic solvent solution containing the composition comprising the obtained physiologically active substance or a salt thereof and a polymer is added to the aqueous phase to form an O (oil phase) / W (aqueous phase) emulsion. After that, the solvent in the oil phase is evaporated to prepare microspheres. In this case, the volume of the aqueous phase is generally about 1 to about 10,000 times, more preferably about 5 to about 50,000 times, and particularly preferably about 10 times the volume of the oil phase.
It is selected from about 2,000 times. An emulsifier may be added to the external water phase in addition to the osmotic pressure adjusting agent described above. The emulsifier may be any one as long as it can generally form a stable O / W emulsion. Specifically, for example,
Anionic surfactants (sodium oleate, sodium stearate, sodium lauryl sulfate, etc.), nonionic surfactants (polyoxyethylene sorbitan fatty acid ester [Tween 80, Tween 6
0, Atlas Powder Co., Ltd., polyoxyethylene castor oil derivatives [HCO-60, HCO-50, Nikko Chemicals], etc.),
Polyvinylpyrrolidone, polyvinyl alcohol, carboxymethyl cellulose, lecithin, gelatin, hyaluronic acid and the like are used. One of these may be used, or some of them may be used in combination. When using, the concentration is
It is preferably used in the range of about 0.01 to 10% by weight, more preferably in the range of about 0.05 to about 5% by weight.

As a method for removing the organic solvent, a method known per se or a method analogous thereto is used. For example, a method of evaporating the organic solvent by stirring at a propeller stirrer or a magnetic stirrer at atmospheric pressure or gradually reducing the pressure, a method of evaporating the organic solvent while adjusting the degree of vacuum using a rotary evaporator, etc. And so on. The microspheres thus obtained are separated by centrifugation or filtration, and then the free bioactive substance attached to the surface of the microsphere,
The emulsifier and the like are repeatedly washed several times with distilled water, dispersed again in distilled water, and freeze-dried. During the manufacturing process, an anti-agglomeration agent may be added to prevent the particles from aggregating. Examples of the aggregation inhibitor include water-soluble polysaccharides such as mannitol, lactose, glucose, starches (eg, corn starch etc.), amino acids such as glycine, proteins such as fibrin, collagen and the like. Above all,
Mannitol is preferred. The amount of anti-aggregating agent such as mannitol added is usually 0 with respect to the entire microsphere.
Is about 24% by weight.

After freeze-drying, if necessary, the microspheres may be heated under reduced pressure under conditions where the microspheres are not fused to each other to remove water and organic solvent. Preferably, the heating is performed at a temperature near the midpoint glass transition temperature of the high molecular weight polymer determined by a differential scanning calorimeter at a temperature rising rate of 10 to 20 ° C. per minute or at a temperature slightly higher than that. More preferably, the polymer is heated near the midpoint glass transition temperature of the polymer or in a temperature range higher by about 30 ° C. than that. In particular, when a lactic acid-glycolic acid polymer is used as the high molecular weight polymer, it is preferably near the midpoint glass transition temperature or at a temperature range higher by 10 ° C., more preferably near the midpoint glass transition temperature or higher. Is also heated in a temperature range higher by 5 ° C. Although the heating time depends on the amount of microspheres,
Generally, it is about 12 hours to about 168 hours, preferably about 24 hours to about 120 hours, particularly preferably about 48 hours to about 96 hours after the microsphere itself reaches a predetermined temperature. The heating method is not particularly limited as long as it is a method capable of uniformly heating the microsphere assembly. As the heating / drying method, for example, a method of heating / drying in a constant temperature tank, a fluidized tank, a moving tank or a kiln, a method of heating / drying with a microwave and the like are used. Among them, the method of heating and drying in a constant temperature bath is preferable.

(II) W / O / W Method First, an organic solvent solution of a polymer is prepared. Examples of the organic solvent include halogenated hydrocarbons (eg, dichloromethane, chloroform, dichloroethane, trichloroethane, carbon tetrachloride, etc.), ethers (eg, ethyl ether, isopropyl ether, etc.), fatty acid esters (eg,
Ethyl acetate, butyl acetate etc.), aromatic hydrocarbons (eg benzene, toluene, xylene etc.), alcohols (eg ethanol, methanol etc.), acetonitrile etc. are used. Of these, halogenated hydrocarbons are preferable, and dichloromethane is particularly preferable. You may mix and use these at an appropriate ratio. In that case, a mixed liquid of a halogenated hydrocarbon and alcohols is preferable, and a mixed liquid of dichloromethane and ethanol is particularly preferable. The concentration of the high molecular weight polymer in the organic solvent solution varies depending on its molecular weight and the type of the organic solvent. For example, when dichloromethane is used as the organic solvent, it is generally about 0.5 to about 70% by weight, more preferably Is selected from about 1 to about 60% by weight, particularly preferably about 2 to about 50% by weight.

Next, a solution of a physiologically active substance or a salt thereof or a salt thereof is added to an organic solvent solution (oil phase) of a high molecular weight polymer [as the solvent, water, water and alcohols (eg, methanol, ethanol, etc.) Mixed solution] is added. This mixture is emulsified by a known method such as a homogenizer or ultrasonic waves to form a W / O emulsion. Then, a W / O emulsion consisting of the obtained physiologically active substance or its salt and a high molecular weight polymer is added to the aqueous phase, and W (internal aqueous phase) /
After forming an O (oil phase) / W (outer water phase) emulsion, the solvent in the oil phase is evaporated to prepare microspheres. The volume of the outer water phase at this time is generally about 1 of the oil phase volume.
Times to about 10,000 times, more preferably about 5 times to about 5 times
10,000 times, particularly preferably about 10 times to about 2,000 times
Selected from double. The emulsifiers and osmotic pressure regulators that may be added to the outer aqueous phase, and the subsequent preparation method are the same as those described in the above item (I). An emulsifier may be added to the above external water phase. The emulsifier may be any one as long as it can generally form a stable O / W emulsion. Specifically, for example, anionic surfactants (sodium oleate, sodium stearate, sodium lauryl sulfate, etc.), nonionic surfactants (polyoxyethylene sorbitan fatty acid ester [Tween 80, Tween (Tween) ) 60, Atlas Powder Co., Ltd., polyoxyethylene castor oil derivatives [HCO-60, HCO-50, Nikko Chemicals], etc.), polyvinylpyrrolidone, polyvinyl alcohol, carboxymethylcellulose, lecithin, gelatin, hyaluronic acid and the like are used. One of these may be used, or some of them may be used in combination. When used, the concentration is preferably in the range of about 0.01 to 10% by weight, more preferably in the range of about 0.05 to about 5% by weight.

As a method for removing the organic solvent, a method known per se or a method analogous thereto is used. For example, a method of evaporating the organic solvent by applying atmospheric pressure or gradually reducing the pressure while stirring with a propeller-type stirrer, a magnetic stirrer, an ultrasonic generator, or the like, or an organic solvent while adjusting the degree of vacuum using a rotary evaporator or the like. Examples thereof include a method of evaporating the solvent and a method of gradually removing the organic solvent by using a dialysis membrane. The microspheres thus obtained are separated by centrifugation or filtration, and then the free bioactive substance or its salt or its salt, drug-holding substance, emulsifier, etc. adhering to the surface of the microsphere is distilled. It is repeatedly washed with water several times, dispersed again in distilled water, and freeze-dried. During the manufacturing process, an anti-agglomeration agent may be added to prevent the particles from aggregating. Examples of the aggregation inhibitor include water-soluble polysaccharides such as mannitol, lactose, glucose, starches (eg, corn starch etc.), amino acids such as glycine, proteins such as fibrin, collagen and the like. Of these, mannitol is preferred. The amount of the anticoagulant such as mannitol added is usually 0 to the total amount of the microspheres.
It is about 24% by weight.

After freeze-drying, if necessary, the microspheres may be heated under reduced pressure under conditions where the microspheres are not fused to each other to remove water and organic solvent from the microspheres. Preferably, the heating is carried out at a temperature slightly higher than the midpoint glass transition temperature of the high molecular weight polymer determined by a differential scanning calorimeter under the condition of a heating rate of 10 to 20 ° C. per minute. More preferably, the heating is carried out within a temperature range which is about 30 ° C. higher than the midpoint glass transition temperature of the polymer. In particular, when a lactic acid-glycolic acid polymer is used as the lactic acid polymer, it is preferably in the temperature range above the midpoint glass transition temperature and 10 ° C. higher than the midpoint glass transition temperature, more preferably above the midpoint glass transition temperature and above the midpoint. Heating is performed in a temperature range that is 5 ° C higher than the glass transition temperature. Although the heating time varies depending on the amount of microspheres and the like, it is generally about 12 hours to about 168 hours, preferably about 24 hours to about 120 hours, particularly preferably after the microsphere itself reaches a predetermined temperature. It is about 48 hours to about 96 hours. The heating method is not particularly limited as long as it is a method capable of uniformly heating the microsphere assembly. As the heating / drying method, for example, a method of heating / drying in a constant temperature tank, a fluidized tank, a moving tank or a kiln, a method of heating / drying with a microwave and the like are used. Among them, the method of heating and drying in a constant temperature bath is preferable.

The microspheres of the present invention obtained by the production method of the present invention are injectable spherical fine particles which can be dispersed in a solution. The form can be confirmed, for example, by observation with a scanning electron microscope.
As the microspheres, microcapsules and microparticles are used, and microcapsules are preferable. The weight ratio of the physiologically active substance or its salt in the microspheres of the present invention varies depending on the type of the physiologically active substance or its salt, the desired pharmacological effect and the duration of the effect. Alternatively, in the case of a salt thereof, about 0.001 to about 50% by weight, preferably about 0.02 to about 40% by weight, more preferably about 0.1 to about 30% by weight, further preferably about 0.1 to about 10% by weight. 24% by weight, most preferably about 3 to about 2
It is 4% by weight, and in the case of a non-peptide bioactive substance or a salt thereof, it is about 0.01 to about 80% by weight, preferably about 0.1 to about 50% by weight. The weight ratio of the high molecular weight polymer in the microspheres of the present invention is about 50 to about 100% by weight, preferably about 70 to about 100% by weight, and more preferably about 85 to about 95, based on the whole microspheres.
% By weight. The weight ratio of the drug-retaining substance in the microspheres of the present invention is
About 0.01 to about 50% by weight, preferably about 0.1 to about 3
It is 0% by weight, more preferably about 5 to about 15% by weight.
The microsphere of the present invention has few surface small pores and is excellent in dispersibility in a suspension for injections and the like. As described above, since the microspheres of the present invention have excellent dispersibility, a large amount of microspheres can be suspended in a suspension for injections or the like. Therefore, even if a drug holding substance such as hydroxynaphthoic acid is not contained in the microspheres, as a result, a large amount of the physiologically active substance or a salt thereof can be contained in the suspension for injection.

The microspheres of the present invention may be formulated into various dosage forms as they are or using these as raw materials, and injections or implants for intramuscular, subcutaneous, organ, etc., transmucosal administration to nasal cavity, rectum, uterus, etc. Agents, oral agents (eg, capsules (eg, hard capsules, soft capsules, etc.), granules,
Solid preparations such as powders, syrups, emulsions, liquids such as suspensions, etc.) and the like. For example, in order to use the microspheres of the present invention as injections, these are used as dispersants (eg, Tween 80, surfactants such as HCO-60, polysaccharides such as sodium hyaluronate, carboxymethylcellulose, sodium alginate). Etc.), preservatives (eg, methylparaben, propylparaben, etc.), isotonic agents (eg, sodium chloride, mannitol, sorbitol, glucose, proline, etc.), etc. as an aqueous suspension together with a dispersion medium, or sesame oil, corn A sustained-release injection that can be actually used as an oily suspension can be prepared by dispersing it together with a dispersion medium such as vegetable oil such as oil. The particle size of the microspheres of the present invention, when used as a suspension injection,
It may be in a range that satisfies the degree of dispersion and needle penetration, and for example, the average particle size is in the range of about 0.1 to 300 μm, preferably about 0.5 to 150 μm, and more preferably about 1
To 100 μm. Examples of aseptic preparations of the microspheres of the present invention include, but are not limited to, a method of sterilizing all manufacturing steps, a method of sterilizing with gamma rays, and a method of adding a preservative. Furthermore, the sustained-release injection of microspheres described above is a suspension, in addition to the above composition, an excipient (eg, mannitol, sorbitol, lactose, glucose, etc.) is added, redispersed, and then frozen. When dried or spray-dried to be solidified, distilled water for injection or a suitable dispersion medium is added at the time of use,
A more stable sustained-release injection can be obtained. When an excipient such as mannitol is added to the sustained-release injection of microspheres, the content of the excipient is about 0 to 5 relative to the whole injection.
It is 0% by weight, preferably about 1 to 20% by weight. When a sustained-release injection of microspheres is used and dispersed in distilled water for injection or an appropriate dispersion medium, the content of the microspheres is about 1 to 80% by weight based on the total amount of the dispersion medium and the microspheres. It is preferably about 10 to 60% by weight.

To prepare the microspheres of the present invention for oral administration, the microspheres of the present invention can be prepared by, for example, an excipient (eg, lactose, sucrose, starch, etc.), a disintegrating agent (eg, starch) according to a method known per se. , Calcium carbonate, etc.),
Binder (eg, starch, gum arabic, carboxymethyl cellulose, polyvinylpyrrolidone, hydroxypropyl cellulose, etc.) or lubricant (eg, talc, magnesium stearate, polyethylene glycol 600)
0 or the like) and the like, followed by compression molding, and if necessary, coating by a method known per se for the purpose of taste masking, enteric property or sustainability, to give an oral administration preparation. Examples of the coating agent include hydroxypropylmethylcellulose, ethylcellulose, hydroxymethylcellulose, hydroxypropylcellulose, polyoxyethylene glycol, Tween 80, Bluronic F68, cellulose acetate phthalate, hydroxypropylmethylcellulose phthalate, hydroxymethylcellulose acetate succinate, Eudragit (Rohm Corporation). Made in West Germany, methacrylic acid / acrylic acid copolymerization) and pigments such as titanium oxide and red iron oxide are used.

In order to make the microspheres of the present invention into nasal preparations, the microspheres produced by the method of the present invention are made into solid, semisolid or liquid nasal preparations according to a method known per se. You can For example, as the solid, the microspheres may be used as they are, or may be used as an excipient (eg, glucose, mannitol, starch, microcrystalline cellulose, etc.), a thickener (eg, natural gums, cellulose derivative, acrylic acid). Polymer, etc.) are added and mixed to obtain a powdery composition. The above-mentioned liquid form is almost the same as the case of the injection, and is an oily or aqueous suspension. In the case of semi-solid form, an aqueous or oily gel or ointment form is preferable. In addition, all of these are pH adjusting agents (eg, carbonic acid, phosphoric acid, citric acid,
Hydrochloric acid, sodium hydroxide, etc.), preservatives (eg, paraoxybenzoic acid esters, chlorobutanol, benzalkonium chloride, etc.) and the like may be added.

In order to make the microspheres of the present invention into suppositories, the microspheres produced by the method of the present invention are made into oily or aqueous solid, semisolid or liquid suppositories according to a method known per se. You can The oily base used in the above composition may be one that does not dissolve microspheres, for example, glycerides of higher fatty acids [eg, cacao butter, Witepsols (Dynamite Nobel), etc.], intermediate fatty acids [eg, migliols] (Dynamite Nobel) and the like], or vegetable oil (eg, sesame oil, soybean oil, cottonseed oil, etc.) and the like. Also,
Examples of the aqueous base include polyethylene glycols and propylene glycol, and examples of the aqueous gel base include natural gums, cellulose derivatives, vinyl polymers and acrylic acid polymers. The microspheres of the present invention are preferably used as an injection.
The content of the microspheres of the present invention in the sustained release composition of the present invention is not particularly limited, but is about 70% by weight of the sustained release composition.
It is preferable to contain the above.

Since the microspheres of the present invention have low toxicity, they can be used as a safe drug for mammals (eg, humans, cows, pigs, dogs, cats, mice, rats, rabbits, etc.). . The dose of the microsphere of the present invention or the sustained-release composition thereof may be determined according to the type and content of the physiologically active substance or its salt as the main drug, the dosage form, the duration of the release of the physiologically active substance or its salt, the target disease, and the target animal. The amount of the physiologically active substance or a salt thereof may be an effective amount, although it varies depending on the factors. 1 of the physiologically active substance or its salt which is the main drug
The dose per administration is, for example, 6 for the sustained release composition.
In the case of a monthly preparation, it can be suitably selected from the range of about 0.01 mg to 10 mg / kg body weight, more preferably about 0.05 mg to 5 mg / kg body weight per adult. The dose of microspheres per administration is preferably about 0.05 mg per adult.
~ 50 mg / kg body weight, more preferably about 0.
It can be appropriately selected from the range of 1 mg to 30 mg / kg body weight. The frequency of administration is once every few weeks, once every month, or once every few months (eg, 3 months, 4 months, 6 months, etc.), etc. The type of physiologically active substance or its salt that is the main drug And content, dosage form, duration of bioactive substance or its salt release,
It can be appropriately selected depending on the target disease, the target animal, and the like.

The microsphere of the present invention or a sustained release composition thereof can be used as a prophylactic / therapeutic agent for various diseases depending on the kind of the physiologically active substance or its salt contained therein. When the active substance or a salt thereof is a LH-RH derivative, a hormone-dependent disease, particularly sex hormone-dependent cancer (eg, prostate cancer, uterine cancer,
Breast cancer, pituitary tumor, etc.), benign prostatic hyperplasia, endometriosis,
Prevention and treatment of sex hormone-dependent diseases such as uterine fibroids, precocious puberty, dysmenorrhea, amenorrhea, premenstrual syndrome, multilocular ovary syndrome, and prevention of diseases such as Alzheimer's disease and immunodeficiency When using the therapeutic agent and contraception (or the rebound effect after withdrawal of the drug)
It can be used as a therapeutic agent. Furthermore, it can be used as a prophylactic / therapeutic agent for benign or malignant tumors that are LH-RH-sensitive but not sex hormone-dependent. Further, in order to produce the microspheres having improved dispersibility of the present invention, an osmotic pressure adjusting agent is used in the outer aqueous phase when an emulsion containing a physiologically active substance or a salt thereof and a polymer is dried in water. can do.

Hereinafter, the present invention will be described in detail with reference to Reference Examples and Examples, but the present invention is not limited thereto.

[0045]

EXAMPLES The weight average molecular weight and the content of each polymer in the following Reference Examples and Examples are polystyrene-equivalent weight average molecular weights measured by gel permeation chromatography (GPC) using monodisperse polystyrene as a reference substance and It is the calculated content of each polymer. In addition, all measurements are high-speed GPC equipment (manufactured by Tosoh Corporation; HLC
-8120 GPC), using SuperH4000 × 2 and SuperH2000 (both manufactured by Tosoh Corporation) as columns, and using tetrahydrofuran as a mobile phase at a flow rate of 0.6 mL / min.
The detection method is based on the differential refractive index.

Reference Example 1 Synthesis of high-molecular-weight lactic acid polymer In 230 mL of dehydrated xylene, 4.1 mL of 1.0 mol / L diethyl zinc hexane solution, tert-butyl lactate 1.35
g and 230 g of DL-lactide, 120-130
A polymerization reaction was carried out at a temperature of about 2 hours. After the completion of the reaction, 120 mL of dichloromethane was poured into the reaction solution, and trifluoroacetic acid 2
30 mL was added to carry out a deprotection reaction. After completion of the reaction, 300 mL of dichloromethane was added to the reaction solution, the reaction solution was poured into 2800 mL of isopropyl ether to precipitate the target substance, and then reprecipitation operation was repeated with dichloromethane / isopropyl ether to give a weight average molecular weight of about 40,000.
A lactic acid polymer of

Reference Example 2 The polymer obtained in Reference Example 1 was treated with 600 mL of dichloromethane.
And washed with water until the liquid property of the solution becomes neutral,
70 g of 90% lactic acid aqueous solution was added and reacted at 40 ° C. When the weight average molecular weight of the polymer dissolved in the reaction solution reached about 20,000, it was cooled to room temperature and 600 mL of dichloromethane was injected to stop the reaction until the reaction solution became neutral. Washed with water. After washing with water, the reaction solution was concentrated and dried to obtain a lactic acid polymer. The terminal carboxyl group of the obtained lactic acid polymer is about 80 μm per 1 g of the polymer.
The content of the polymer having a weight average molecular weight of 5000 or less was 7.29% by weight.

Reference Example 3 (1) 600 mL of dichloromethane was added to the polymer obtained in Reference Example 1.
And washed with water until the liquid property of the solution becomes neutral,
70 g of 90% lactic acid aqueous solution was added and reacted at 40 ° C. When the weight average molecular weight of the polymer dissolved in the reaction solution reached about 20,000, it was cooled to room temperature, 600 mL of dichloromethane was added to stop the reaction, and the reaction solution became neutral. After washing with water, the reaction solution was dropped into 2800 mL of isopropyl ether to precipitate the target lactic acid polymer. The precipitate obtained by decantation was dissolved in 600 mL of dichloromethane, then the solution was concentrated and dried to obtain 160 g of a lactic acid polymer. The amount of terminal carboxyl groups of the obtained lactic acid polymer was about 70 μmol per 1 g of the polymer. Table 1 shows the weight average molecular weight of the high molecular weight lactic acid polymer used, the weight average molecular weight of the lactic acid polymer after the hydrolysis treatment, the weight average molecular weight of the target lactic acid polymer obtained and its molecular weight fraction.

Reference Examples 3 (2) to (6) The same operation as in Reference Example 3 (1) was performed to obtain a lactic acid polymer of the present invention. Table 1 also shows the weight average molecular weight of the high molecular weight lactic acid polymer used, the weight average molecular weight of the lactic acid polymer after the hydrolysis treatment, the weight average molecular weight of the target lactic acid polymer obtained and its molecular weight fraction.

[0050]

[Table 1] As is clear from Table 1, the lactic acid polymer of the present invention obtained by the method of the present invention has a polymer content of a weight average molecular weight of 5000 or less of about 5% by weight or less and a weight average molecular weight of 3000 or less. It can be seen that the content is about 1.5% by weight or less and the content of the polymer having a weight average molecular weight of 1000 or less is about 0.1% by weight or less.

Comparative Example 1 DL-lactic acid polymer obtained by the same method as in Reference Example 3 (1) (weight average molecular weight 21,400, carboxyl group amount by labeling quantitative method 76.1 μmol / g) 205.5
A solution of 35 g of dichloromethane in 354.3 g was added to a solution of 0.
2μm filter (EMFLOW, DFA4201F
It was filtered under pressure with RP) and adjusted to 28.8 ° C. 380.4 g of this organic solvent solution was weighed, 16.11 g of the peptide A acetate salt was dissolved in 16.22 g of distilled water, and 55.
The mixture was mixed with an aqueous solution heated to 4 ° C., stirred for 1 minute to coarsely emulsify, and then emulsified using a minimixer at 10,150 rpm for 2 minutes to form a W / O emulsion. Then, this W / O emulsion was cooled to 18 ° C. and then added to 25 liters of a 0.1% (w / w) polyvinyl alcohol (EG-40, manufactured by Nippon Synthetic Chemical Industry) aqueous solution which had been adjusted to 18.7 ° C. in advance. Injection in 3 minutes 10 seconds, HOMOMI
7, 0 using C LINE FLOW
The mixture was stirred at 01 rpm to give a W / O / W emulsion. The temperature of this W / O / W emulsion was adjusted at about 18.5 ° C. for 30 minutes, and then the mixture was stirred for 2 hours and 30 minutes without adjusting the temperature to volatilize or diffuse dichloromethane and ethanol into the external water phase to solidify the oil phase. After that, the mixture was sieved using a 75 μm mesh sieve and then a centrifuge (H-600
S, manufactured by a domestic centrifuge) was used to continuously sediment the microspheres at 2,000 rpm for collection. The collected microspheres are redispersed in a small amount of distilled water and
Mannitol 1 after sieving using a sieve with an opening of m
After adding and dissolving 8.85g, it was freeze-dried and obtained as powder. The mass recovery of microsphere powder is 11
At 7.6 g, the recovery was 68.54% and the peptide A content was 7.76%. An electron micrograph of the obtained microspheres is shown in FIG.

Example 1 DL-lactic acid polymer obtained by the same method as in Reference Example 3 (1) (weight average molecular weight 21,400, amount of carboxyl group by labeling quantitative method 76.1 μmol / g) 205.4
g of dichloromethane in 354.4 g was dissolved in about 3
The temperature was adjusted to 0 ° C. 380.5 g of this solution was weighed out, 16.1 g of leuprorelin acetate was dissolved in 16.2 g of distilled water and mixed with an aqueous solution heated to about 55 ° C., and a mini mixer (made by Tokushu Kiki) was used. The emulsion was emulsified to form a W / O emulsion (rotation speed: about 10,000 rpm). Then this W /
After cooling the O emulsion to about 18 ° C, 0.1% (w / w) polyvinyl alcohol (EG
-40, manufactured by Nippon Synthetic Chemical Industry) + 1% mannitol aqueous solution 2
Inject into 5 liters and use HOMOMIC LINE
Secondary emulsification using FLOW (manufactured by Tokushu Kika) W / O / W
The emulsion was used (turbine rotation speed: about 7,000 rpm, circulation pump rotation speed: about 2000 rpm). This W / O / W emulsion is dried in water for about 3 hours, sieved using a standard sieve of 75 μm, and then the microspheres are continuously settled using a centrifuge (H-600S, domestic centrifuge). And collected (rotation speed about 2,000 rpm, flow rate about 600 ml
/ Min). The collected microspheres were re-dispersed in a small amount of distilled water and sieved using a 90 μm standard sieve.
Mannitol 18.9g was added and freeze dryer (TRI
It was freeze-dried with OMASTER, manufactured by Kyowa Vacuum Co., Ltd. to obtain powder (microsphere powder). An electron micrograph of the obtained microspheres is shown in FIG.

Experimental Example 1 About 660 mg of microsphere powder produced in Comparative Example 1 and Example 1 was weighed into a coated 9P vial, capped with a rubber stopper, and tightened with a cap. 1.5mL of dispersion medium for leuprorelin acetate (5% mannitol + 1% sodium carmellose + 0.1% polysorbate 80)
Was added and the time for uniform dispersion was measured. Dispersion operation is in accordance with the method described in the instruction manual for the preparation of leuprorelin acetate for vials, with an amplitude of about 7 cm and an amplitude speed of about 30 times / 1.
It went in 0 seconds. The results are shown in Table 2.

Experimental Example 2 Approximately 660 mg of the microsphere C powder prepared in Comparative Example 1 and Example 1 was filled with a dispersion medium for leuprorelin acetate (dispersion amount: 1.5 mL) and a 14φ type DPS (dual chamber prefilled syringe). ), Was suspended, and the time for uniform dispersion was measured. The dispersion operation is in accordance with the method described in the instruction manual for the DPS preparation of leuprorelin acetate, and tapped on the palm to have an amplitude of about 3 cm,
The amplitude speed was about 50 times / 10 seconds. The results are shown in Table 3.

[0055]

Since the microspheres of the present invention have excellent dispersibility, they can be dispersed at a high concentration in a dispersion medium such as distilled water for injection.

[0056]

[Brief description of drawings]

FIG. 1 shows an electron micrograph of a microsphere of Comparative Example 1.

FIG. 2 shows an electron micrograph of the microspheres of Example 1.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) A61K 47/34 A61K 47/42 47/42 A61P 13/08 A61P 13/08 15/00 15/00 15 / 18 15/18 35/00 35/00 A61K 37/24 (72) Inventor Tsuguichi Arai F-Term (reference) 4C076 AA67 AA94 BB11 CC30 DD37 DD51 No. 9-45-210 Motoyama Minamimachi 8-chome, Higashinada-ku, Kobe City, Hyogo Prefecture DD67 EE24 EE41 FF31 GG28 GG29 4C084 AA01 AA03 BA01 BA09 BA17 CA59 DB09 DB71 MA05 NA14 ZA812 ZA862 ZB262

Claims (29)

[Claims] 1. A method for producing microspheres having improved dispersibility, which comprises adding an osmotic pressure adjusting agent to an outer aqueous phase during the production of microspheres by an in-water drying method. 2. The process according to claim 1, wherein the improved dispersibility is such that about 400 to about 700 mg of microspheres can be dispersed in 1.5 mL of injectable dispersion medium in less than 2 minutes. 3. The method according to claim 1, wherein a W / O / W type emulsion is used in the in-water drying method. 4. The method according to claim 3, wherein the inner aqueous phase further contains a drug holding substance. 5. The method according to claim 1, wherein an O / W type emulsion is used in the underwater drying method. 6. The method according to claim 1, wherein an S / O / W type emulsion is used in the in-water drying method. 7. A W / O emulsion in which a liquid containing a physiologically active substance or a salt thereof is used as an inner aqueous phase and a solution containing a lactic acid polymer having a weight average molecular weight of 15,000 to 50,000 or a salt thereof is used as an oil phase is permeated. A method for producing microspheres, which comprises dispersing in an external water phase containing a pressure regulator and subjecting it to an in-water drying method. 8. The method according to claim 7, wherein the content of the polymer having a weight average molecular weight of 5000 or less in the lactic acid polymer or a salt thereof is about 10% by weight or less. 9. The content of the polymer having a weight average molecular weight of 5000 or less in the lactic acid polymer or a salt thereof is about 5% by weight or less,
The manufacturing method according to claim 7. 10. The method according to claim 7, wherein the content of the polymer having a weight average molecular weight of 3000 or less in the lactic acid polymer or a salt thereof is about 1.5% by weight or less. 11. The method according to claim 7, wherein the content of the polymer having a weight average molecular weight of 1000 or less in the lactic acid polymer or a salt thereof is about 0.1% by weight or less. 12. The method according to claim 7, wherein the lactic acid polymer or a salt thereof has a weight average molecular weight of 15,000 to 40,000. 13. The method according to claim 7, wherein the lactic acid polymer or its salt has a weight average molecular weight of 17,000 to 26,000. 14. The osmotic pressure adjusting agent is alcohols, sugars,
The production method according to claim 1 or 7, which is an amino acid, a peptide, a protein, a salt of a water-soluble amino acid, a derivative thereof, or a mixture thereof. 15. The method according to claim 1, wherein the osmotic pressure adjusting agent is mannitol. 16. The concentration of the osmotic pressure adjusting agent in the outer aqueous phase is such that the osmotic pressure of the outer aqueous phase is about 1/50 to about 5 times the osmotic pressure of physiological saline. The manufacturing method described. 17. The method according to claim 7, wherein the physiologically active substance is a water-soluble physiologically active substance. 18. The method according to claim 7, wherein the physiologically active substance is a physiologically active peptide. 19. The method according to claim 7, wherein the physiologically active substance is an LH-RH derivative. 20. The LH-RH derivative has the formula 5-oxo-Pro-His-Trp-Ser-Tyr-Y-Leu-Arg-Pro-Z [wherein Y is DLeu, DAla, DTrp, DSer (tBu). , D2Nal or
DHis (ImBzl) is shown, and Z is NH-C ₂ H ₅ or Gly-NH ₂ . ] It is a peptide represented by these, or its salt.
The manufacturing method described. 21. A microsphere obtained by the method according to claim 1 or 7. 22. A sustained-release composition containing the microsphere according to claim 21. 23. Prostate cancer, benign prostatic hyperplasia, endometriosis,
23. Use for the prevention, treatment or contraception of uterine fibroids, uterine fibroids, precocious puberty, dysmenorrhea or breast cancer.
The sustained-release composition of. 24. The sustained-release composition according to claim 22, which is for injection. 25. The method according to claim 2, further comprising mannitol.
The sustained-release composition according to 2. 26. The sustained-release composition according to claim 22, which contains the microsphere in an amount of about 70% by weight or more based on the entire composition. 27. Prostate cancer, benign prostatic hyperplasia, endometriosis, uterine fibroids, uterine fibroids, which comprises administering an effective amount of the sustained release composition according to claim 22 to a mammal. , Precocious puberty, dysmenorrhea or breast cancer prevention / treatment or contraception. 28. An osmotic pressure adjusting agent is added to an outer aqueous phase when an emulsion containing a physiologically active substance or a salt thereof and a high molecular polymer is dried in water to produce microspheres having improved dispersibility. A method characterized by being present. 29. In an external water phase when an emulsion containing a physiologically active substance or a salt thereof and a high molecular weight polymer is dried in water to produce a microsphere having improved dispersibility,
Use of osmotic pressure regulators.