United States Patent:   5,976,571

Assignee:  Port Systems, L.L.C. (Ann Arbor, MI)

Filed:  October 7, 1997

A drug delivery system (10) includes a first capsule half (12) having an inner chamber (16) for containing a drug (18) therein. A plug (28) is disposed in a passageway (26) of the capsule half (12) for plugging the opening (24) thereof. The plug (28) is releasable from the passageway opening (24) upon the application of pressure from within the inner chamber (16). A pump mechanism, reactive with the external environment of the capsule half (12), causes an increase in pressure within the inner chamber (16) and forces the plug (28) out of the passageway (26) to release the drug (18) from the inner chamber (16) and out of the passageway (26). Thusly, after initial release of drug from a second capsule half (14) releasably mounted on the first capsule half (12), the first capsule half (12) provides a second pulse of drug release at a predetermined time after initial ingestion of the capsule. The invention further provides a method of manufacturing the drug delivery system (10) and method by which the drug delivery system (10) provides the drug to a body.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a drug delivery system comprising a first container including an inner chamber for containing a drug therein and having a passageway opening to an external environment thereof. Plug means is disposed in the passageway for plugging and closing the opening. The plug means is releasable from the opening upon the application of pressure from within the inner chamber. The container includes pump means reactive to the external environment for increasing the pressure within the inner chamber and forcing the plug means out of the passageway to release the drug from the chamber and out of the passageway.

The present invention further provides a method of delivering a drug to a body, the method including the steps of ingesting a drug delivery system, immediately releasing a first predetermined amount of drug from a second chamber of the system, and increasing the pressure within a first chamber of the system over time and forcing a plug therefrom at a predetermined time after the ingesting step. The drug is released from the first chamber once the plug is released therefrom.

The present invention further provides a method of making a drug delivery system, the method including the steps of filling a first capsule half with drug and a reactive agent, the capsule being water permeable. The capsule is plugged and a water permeable film is disposed over the capsule and plug. A second capsule half is filled with drug and an open end thereof is releasably mounted over the plugged end of the first capsule half.

Also, in accordance with the present invention, there is provided a method of making a drug delivery system includes the steps of filling a first capsule half with a drug and an osmotic agent, the capsule being water permeable. The method further includes the step of plugging an open-end of the capsule, disposing a water permeable film over the capsule and plug, filling a second capsule half with a drug, and releasably mounting an open end of the second capsule half over the plugged end of the first capsule half.

Claim 1 of 29 Claims

1. A drug delivery system (10) consisting essentially of: a first container (12) defining at least one inner chamber (16) for containing drug (18) therein and having a passageway (26) opening to an external environment thereof, said container (12) being fluid permeable; a second container (14) having an open end (34) releasably mounted on said first container (12) and closed thereby for forming a closed second chamber (36) therein for containing drug (18), said second container (14) being releasable from said first container (12) upon ingestion to release drug (18); and a fluid impermeable plug (28) disposed in said passageway (26) for plugging said opening (24) closed, said plug (28) being slidably releasable from said opening (24) upon the application of fluid pressure from within said inner chamber (16), said container (12 including an osmotic reagent for increasing the pressure within said inner chamber (16) when disposed in a fluid environment and forcing said plug (28) constructed of a polymeric material selected from the group consisting of polyurethane, ethylmethylacrylate and hydroxyethyl methylacrylate to slide out of said passageway (26) to release the drug (18) from said inner chamber (16) and out of said passageway (26).

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