Claims
- 1. A sustained-release microcapsule comprising a bioactive substance obtained by encapsulating said bioactive substance in a homopolymer or copolymer of lactic acid/glycolic acid having a lactic acid/glycolic acid ratio of 100/0 to 50/50 mol %, and thermally drying the obtained microcapsule at a temperature ranging from the glass transition point of said homopolymer or copolymer of lactic acid/glycolic acid to a temperature up to 5° C. higher than the glass transition point of the homopolymer or copolymer of lactic acid/glycolic acid for about 24 to about 120 hours to produce a sustained-release microcapsule comprising relative to the weight of the sustained-release microcapsule, not less than 60% by weight of the homopolymer or copolymer of lactic acid/glycolic acid based on the weight of the microcapsule.
- 2. Microcapsules of claim 1 which is for injection.
- 3. An agent for treatment or prevention of sex hormone-dependent diseases or a contraceptive which comprises the sustained-release microcapsules of claim 1.
- 4. An agent of claim 3, wherein said sex hormone-dependent disease is prostatic hypertrophy, prostatic cancer, hysteromyoma, endometriosis, dysmenorrhea, precocious puberty or breast cancer.
- 5. A method for treatment or prevention of sex hormone-dependent diseases in a subject which comprises administering to said subject in need an effective amount of the microcapsules of claim 1.
- 6. The sustained-release microcapsule of claim 1, wherein said temperature of the thermal drying is up to 3° C. higher than the glass transition point of the homopolymer or copolymer of lactic acid/glycolic acid.
- 7. The sustained-release microcapsule of claim 1, comprising a copolymer of lactic acid/glycolic acid.
- 8. The sustained-release microcapsule of claim 6, comprising a copolymer of lactic acid/glycolic acid.
- 9. A composition for the treatment or prevention of sex hormone-dependent disease or a contraceptive, made from a microcapsule as claimed in claim 1.
Parent Case Info
This application is a divisional of application Ser. No. 08/704,991, filed Aug. 29, 1996 now U.S. Pat. No. 6,045,830.
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