Method for producing microcapsule
AssigneeTakeda Chemical Industries, Ltd.
InventorsHiroaki Okada, Yasuaki Ogawa, Takatsuka Yashiki
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Abstract
A microcapsule produced by preparing a water-in-oil emulsion comprising an inner aqueous layer containing said water-soluble drug and a drug retaining substance therefor and an oil layer containing a polymer substance, then thickening or solidifying said inner aqueous layer to a viscosity of not lower than about 5000 centiposes and finally subjecting the resulting emulsion to in water drying gives prolonged release of water-soluble drug.
Claims3
A method for producing a prolonged release microcapsule for injection, which comprises redispersing a spherical microcapsule having an average diameter of 2 to 200 .mu.m, comprising particles containing a water-soluble drug, the particles being dispersed in a spherical microcapsule matrix composed of a polymer of lactic acid and glycolic acid having comonomer ratio within the range of about 100/0 to 50/50and an average molecular weight within the range of about 5,000 to 200,000, in an excipient selected from the group consisting of mannitol, sorbitol, lactose and glucose and then solidifying,
- wherein he resulting microcapsule upon reconstitution in a vehicle for injection, provides greater stability than if no redispersing step is performed, and
- wherein the water-soluble drug is (Pyr) Glu-His-Trp-ser-Tyr-D-Leu-Leu-Arg-Pro-NH-C.sub.2 H.sub.5.
Dependencies are inferred from the claim text.