# US 7,407,499 B2 · Osmotic pump with self-retaining, fast-start membrane plug > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,407,499 B2 - Document ID: US7407499B2 - Status: Granted - Kind: B2 - Application number: 10/969,753 - Filed: 2004-10-20 - Published: 2005-05-05 - Granted: 2008-08-05 - Earliest claimed: 2003-10-31 - Assignees: Intarcia Therapeutics, Inc. - Inventors: Joseph C. Trautman - Web page: https://patentgrep.com/patent/US7407499B2 ## CPC - A61K 9/0004: {Osmotic delivery systems; Sustained release driven by osmosis, thermal energy or gas} - A61K: PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES (devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms A61J3/00; chemical aspects of, or use of materials for deodorisation of air, for disinfection or sterilisation, or for bandages, dressings, absorbent pads or surgical articles A61L; soap compositions C11D) ## Abstract An osmotic pump includes a capsule having at least one delivery port formed at a first end and a membrane plug retained in a second end of the capsule remote from the delivery port to provide a fluid-permeable barrier between an interior and an exterior of the capsule. The membrane plug has a columnar body and at least one slot formed in the columnar body to vent pressure from the interior to the exterior of the capsule when the columnar body extends a predetermined distance relative to the second end of the capsule, thereby preventing expulsion of the membrane plug from the second end. ## Claims ### Claim 1 An osmotic pump, comprising: a capsule having a first end and a second end and an interior chamber disposed between the first end and the second end, the capsule having at least one delivery port formed at a the first end; a membrane plug made of a semipermeable material inserted in an opening at the second end of the capsule remote from the delivery port to provide a fluid-permeable baffler between the interior chamber and an exterior of the capsule; wherein the membrane plug has a columnar body bounded externally by a side surface and a base surface and at least one slot formed in the columnar body, the slot being in communication with the base surface and the base surface being in communication with the interior chamber, the slot extending from the base surface and terminating at a non-basal point on the side surface distanced from the base surface to vent pressure from the interior chamber to the exterior of the capsule when the columnar body extends a predetermined distance relative to the second end of the capsule, thereby preventing expulsion of the membrane plug from the second end; wherein an orifice traverses an entire length of the membrane plug such that exterior fluid flows into and through the columnar body through the orifice until the orifice becomes occluded due to swelling of the semipermeable material. ### Claim 2 (depends on 1) The osmotic pump of claim 1, wherein the non-basal point is in a range from 10 to 90% of a length of the columnar body. ### Claim 3 (depends on 1) The osmotic pump of claim 1, wherein the non-basal point is in a range from 20 to 80% of a length of the columnar body. ### Claim 4 (depends on 1) The osmotic pump of claim 1, wherein the non-basal point is in a range from 30 to 60% of a length of the columnar body. ### Claim 5 (depends on 1) The osmotic pump of claim 1, wherein the columnar body terminates in an enlarged end cap remote from the base surface, the end cap having a surface for engagement with the second end of the capsule so as to establish a repeatable position of the columnar body in the capsule. ### Claim 6 (depends on 1) The osmotic pump of claim 1, wherein a plurality of protrusions is provided on the surface of the columnar body for engaging an inner surface of the capsule. ### Claim 7 (depends on 1) The osmotic pump of claim 1, wherein the interior chamber is for containing an osmotic agent and the capsule has another interior chamber for containing a beneficial agent. ### Claim 8 (depends on 7) The osmotic pump of claim 7, further comprising a piston movably disposed between the interior chamber for containing the osmotic agent and the interior chamber for containing the beneficial agent. ### Claim 9 (depends on 1) The osmotic pump of claim 1, wherein the delivery port is provided by a diffusion moderator retained in the first end of the capsule. ### Claim 10 (depends on 1) The osmotic pump of claim 1, wherein a diameter of the orifice is less than 35% of a diameter of the columnar body. ### Claim 11 (depends on 1) The osmotic pump of claim 1, wherein a diameter of the orifice is in a range from 0.8 to 33% of a diameter of the columnar body. ### Claim 12 A membrane plug for use with an osmotic pump having a delivery capsule, comprising: a columnar body made of a semipermeable material and adapted for insertion into an opening at an end of the delivery capsule, the columnar body bounded externally by a side surface and a base surface, the side surface adapted for engagement with an inner surface of the capsule, the columnar body being provided with a slot which is in communication with the base surface, the slot extending from the base surface of the columnar body and terminating on a non-basal point on the side surface of the columnar body distanced from the base surface so that pressure can be selectively vented from the base surface to the side surface; wherein an orifice traverses an entire length of the membrane plug such that exterior fluid flows into and through the columnar body through the orifice until the orifice becomes occluded due to swelling of the semipermeable material. ### Claim 13 (depends on 12) The membrane plug of claim 12, wherein the non-basal point is in a range from 10 to 90% of a length of the columnar body. ### Claim 14 (depends on 12) The membrane plug of claim 12, wherein the non-basal point is in a range from 20 to 80% of the length of the columnar body. ### Claim 15 (depends on 12) The membrane plug of claim 12, wherein the non-basal point is in a range from 30 to 60% of a length of the columnar body. ### Claim 16 (depends on 12) The membrane plug of claim 12, further comprising an enlarged end cap formed on the columnar body, the end cap having a surface for engagement with an end of the capsule so as to achieve a repeatable position of the columnar body in the capsule. ### Claim 17 (depends on 12) The membrane plug of claim 12, wherein a plurality of protrusions is provided on the surface of the columnar body for engagement with the inner surface of the capsule. ### Claim 18 (depends on 12) The membrane plug of claim 12, wherein a diameter of the orifice is less than 35% of a diameter of the columnar body. ### Claim 19 (depends on 12) The membrane plug of claim 12, wherein a diameter of the orifice is in a range from 0.8 to 33% of a diameter of the columnar body.