Minimally compliant, volume-efficient piston for osmotic drug delivery systems

• US 7,112,335 B2
• Filed: 09/06/2005
• Issued: 09/26/2006
• Est. Priority Date: 06/26/2002
• Status: Expired due to Term

• Current Assignee: Intarcia Therapeutics, Inc.
• Original Assignee: ALZA Corporation (Johnson & Johnson)
• Inventors: Lautenbach, Scott D.
• Primary Examiner(s): KENNEDY, SHARON E
• Application Number:
  US11/219,960
• Publication Number:
  US 20060111693A1
• Time in Patent Office: 385 Days
• Field of Search: 604/890.1, 604/892.1, 424/438, 424/424, 424/452, 424/423, 424/433, 424/436, 424/422, 424/425
• US Class Current: 424/424
• CPC Class Codes: A61K 9/0004 Osmotic delivery systems; Sustained release driven by osmosis, thermal energy or gas
• CPC Class Codes: A61K 9/48 Preparations in capsules, e.g. of gelatin, of chocolate A61K9/0004 takes precedence; bite capsules A61K9/0056
• CPC Class Codes: A61M 2005/14513 with secondary fluid driving or regulating the infusion
• CPC Class Codes: A61M 31/002 Devices for releasing a drug at a continuous and controlled rate for a prolonged period of time artificial gland structures or devices A61F2/022; intra-uterine contraceptive devices A61F6/14; tampons for introducing into the vagina A61F13/20, A61L15/00; suppositories or bougies for intra-vaginal or intra-uterine application A61K9/02; physical forms of medicinal preparations for sustained or differential drug release A61K9/20, A61K9/50

Abstract

An osmotic pump having a minimally compliant, volume-efficient piston positioned within a capsule is provided. The capsule has an interior surface, a beneficial agent, and an osmotic agent. The piston is movable with respect to an interior surface of the capsule, and defines a movable seal with the interior surface of the capsule. The movable seal separates the osmotic agent from the beneficial agent. The piston has a length-to-total-diameter ratio of about 1.1:1 and a core-diameter-to-total-diameter ratio of about 0.9:1. The piston enables greater beneficial agent and/or osmotic agent payload without increasing the size of the capsule. The osmotic agent imbibes liquid from a surrounding environment through a semipermeable body to cause the piston to move and, in turn, cause delivery of the beneficial agent from the capsule.

Claims

1. An osmotic delivery system comprising:

a capsule having an interior for holding a beneficial agent;

an osmotic agent located in the interior; and

a movable piston having a length to total diameter ratio of about 1.1;

1 and a core diameter to overall diameter ratio of about 0.9;

1 located within the interior of the capsule, defining a seal with an interior surface of the capsule that separates the osmotic agent from the beneficial agent.

2. The osmotic delivery system according to claim 1, wherein the piston includes one or a plurality of ribs for effecting the seal with the interior surface.

3. The osmotic delivery system according to claim 1, wherein the capsule includes a cylindrical tube.

4. The osmotic delivery system according to claim 3, wherein the cylindrical tube includes an opening and further includes a semipermeable body within the opening.

5. The osmotic delivery system according to claim 1, wherein the osmotic agent includes a tablet.

6. An osmotic delivery system comprising:

a piston having a length to overall diameter ratio not greater than about 1.1;

1 and a core diameter to overall diameter ratio not greater than about 0.9;

1;

an osmotic agent; and

an enclosure having an interior holding the piston and the osmotic agent, the piston being movable with respect to the enclosure.

7. The osmotic delivery system according to claim 6, wherein the interior of the enclosure includes an interior surface, the piston abutting against the interior surface.

8. The osmotic delivery system according to claim 6, further comprising a semipermeable body in liquid communication with the osmotic agent and within the enclosure.

9. The osmotic delivery system according to claim 6, wherein the enclosure is fluid impermeable.

10. The osmotic delivery system according to claim 8, wherein the osmotic agent is located between the semipermeable body and the piston.

11. The osmotic delivery system according to claim 6, further comprising a beneficial agent located in the interior of the enclosure, the beneficial agent being delivered from the enclosure when the piston moves.

12. The osmotic delivery system according to claim 6, wherein the piston is fluid impermeable.

13. The osmotic delivery system according to claim 6, wherein the piston includes at least one rib for effecting a movable seal with the enclosure.

14. The osmotic delivery system according to claim 6, further comprising a beneficial agent located in the interior of the enclosure, the piston defining a movable seal that separates the osmotic agent from the beneficial agent.

15. An osmotic delivery system comprising:

a capsule having a tubular interior, the tubular interior having an interior surface;

a semipermeable body located at least partially within the tubular interior;

an osmotic agent located between the semipermeable body and a piston;

a beneficial agent located within the tubular interior; and

a piston located within the tubular interior, the piston having a length to overall diameter ratio less than about 1.1;

1 and a core diameter to overall diameter ratio less than about 0.9;

1, the piston separating the beneficial agent from the osmotic agent, and being movable with respect to the interior surface of the tubular interior and with respect to the semipermeable body.

16. The osmotic delivery system according to claim 15, wherein the piston includes at least one rib.