United States Patent:  6,004,582

Assignee:  Laboratorios Phoenix U.S.A, Inc. (Buenos Aires, AR)

Filed:  May 29, 1998

The present invention provides a simple and improved multi-layered osmotic device (1) that is capable of delivering a first active agent in an outer lamina (2) to one environment of use and a second active agent in the core (5) to another environment of use. Particular embodiments of the invention provide osmotic devices in which the first and second active agents are similar or dissimilar. An erodible polymer coat (3) between an internal semipermeable membrane (4) and a second active agent-containing external coat (2) comprises poly(vinylpyrrolidone)-(vinyl acetate) copolymer. This particular erodible polymer results in an improved multi-layered osmotic device possessing advantages over related devices known in the art. The active agent in the core (5) is delivered through a pore (6) containing an erodible plug (7). The osmotic device (1) can be coated by a final finish coat (8).

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an improved multi-layered osmotic device that allows the delivery to an environment of use of an active substance present in an external coating as well as the delayed and controlled delivery of an active substance contained in the core of the osmotic device to either the same or a different environment of use.

The present invention provides an improved multi-layered osmotic device for the controlled delivery of one or more active agents to one or more environments of use wherein the osmotic device comprises: a) a compressed core comprising a first active agent, an osmotic agent, and optionally poly(vinylpyrrolidone) for controlled and continuous release of the drug; b) a semipermeable membrane, preferably consisting essentially of cellulose esters, more preferably cellulose acetate esters, and poly(ethylene glycol), surrounding the core and having a preformed passageway therein, said wall being permeable to a fluid in the environment of use and substantially impermeable to the first active agent; c) an inert water soluble polymer coat comprising poly(vinylpyrrolidone)-(vinyl acetate) copolymer partially or substantially completely surrounding the semipermeable membrane and plugging the passageway in the wall; and d) an external coat comprising, optionally poly(vinylpyrrolidone) and poly(ethylene glycol), and a second active agent for immediate release of the drug, wherein the first active agent is released from the core after the external coat has partially or completely dissolved or eroded.

It is contemplated that the first and second active agents can be the same or different. It is also contemplated that the active agents can include compounds such as biologically or pharmacologically active agents, medicines, nutrients, food products, insecticides, pesticides, herbicides, germicides, algaecides, fungicides, chemical reagents, growth regulating substances, parasiticides, sex sterilants, fertility promoters, biocides, rodenticides, disinfectants, anti-oxidants, plant growth promoters, preservatives, fermentation agents, fertility inhibitors, air purifiers, microorganism attenuators, catalysts, foods, food supplements, nutrients, cosmetics, vitamins, and other agents that benefit the environment of use. The present invention also contemplates that the first and second active agents can be delivered to one or more environments of use at different times and at different rates.

Preferred embodiments of the invention include those wherein the first and second active agents are pharmacologically or biologically active agents or wherein the first environment of use is the stomach or gastric region and the second environment of use is the farther down the GI tract of a mammal.

Other preferred embodiments include those wherein: a) the compressed core comprises a first active agent, an osmotic agent and poly(vinylpyrrolidone); b) the semipermeable membrane consists essentially of cellulose acetate and poly(ethyleneglycol); or c) the external coat comprises poly(vinylpyrrolidone), poly(ethylene glycol) and a second active agent. Yet other preferred embodiments include those wherein the first and second active agents are the same and those wherein they are different.

Different environments for use of the osmotic device include biological environments such as the oral, ocular, nasal, vaginal, glands, gastrointestinal tract, rectum, cervical, intrauterine, arterial, venous, otic, sublingual, dermal, epidermal, subdermal, implant, buccal, bioadhesive, mucosal and other similar environments. Likewise, it may be used in aquariums, industrial warehouses, laboratory facilities, hospitals, chemical reactions and other facilities.

Claim 1 of 23 Claims

1. An improved multi-layered osmotic device for the controlled delivery of one or more active agents to one or more environments of use wherein the osmotic device comprises:

a) a compressed core comprising a first active agent and an osmotic agent for controlled and continuous release of the drug;

b) a semipermeable membrane surrounding the core and having a preformed passageway therein, said membrane being permeable to a fluid in the environment of use and substantially impermeable to the first active agent;

c) an inert, completely erodible water soluble polymer coat comprising poly(vinylpyrrolidone)-(vinyl acetate) copolymer partially or substantially completely surrounding the semipermeable membrane and plugging the passageway in the wall; and

d) an external coat comprising a second active agent for immediate release of the drug, wherein the first active agent is released from the core after the polymer coat has partially or completely dissolved or eroded, and the first and second active agents are released into the same or different environments of use to provide a controlled delivery of the one or more active agents.

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