Prolonged release microcapsule
AssigneeTakeda Chemical Industries, Ltd.
InventorsHiroaki Okada, Yasuaki Ogawa, Takatsuka Yashiki
Life of this patent
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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.
Claims8
A prolonged release microcapsule for injection, which comprises particles containing a water-soluble drug, the particles being dispersed in a spherical microcapsule matrix composed of a copolymer of lactic acid and glycolic acid having a comonomer ratio within the range of about 100/0 to 50/50 and an average molecular weight within the range of about 5,000 to 200,000, the spherical microcapsule matrix having an average diameter of 2 to 200 .mu.m, and an excipient selected from the group consisting of mannitol, sorbitol, lactose and glucose, which particles are produced by in-water drying.
An injectable preparation comprising a therapeutically effective amount of a prolonged release microcapsule which comprises particles containing a water-soluble drug, the particles being dispersed in a spherical microcapsule matrix composed of a copolymer of lactic acid and glycolic acid having a comonomer ratio within the range of about 100/0 to 50/50 and an average molecular weight within the range of about 5,000 to 200,000, the spherical microcapsule matrix having an average diameter of 2 to 200 .mu.m, and an excipient selected from the group consisting of mannitol, sorbitol, lactose and glucose, which particles are produced by in-water drying.
Dependencies are inferred from the claim text.