Lacrimal implants and related methods

• US 20090264861A1
• Filed: 02/17/2009
• Published: 10/22/2009
• Est. Priority Date: 02/18/2008
• Status: Active Grant

• Current Assignee: Mati Therapeutics, Inc
• Original Assignee: QLT Plug Delivery, Inc.
• Inventors: Shimizu, Robert W., Jain, Rachna
• Granted Patent: US 9,216,108 B2
• Time in Patent Office: Days
• US Class Current: 604/521
• CPC Class Codes: A61B 17/12022 Occluding by internal devices, e.g. balloons or releasable wires plugging an opening in the wall of an organ A61B17/0057; occluders for the cervical canal A61F6/146; vas deferens occluders A61F6/20
• CPC Class Codes: A61F 2210/0061 swellable
• CPC Class Codes: A61F 9/0017 implantable in, or in contact with, the eye, e.g. ocular inserts
• CPC Class Codes: A61F 9/00772 Apparatus for restoration of tear ducts
• CPC Class Codes: A61F 9/00781 Apparatus for modifying intraocular pressure, e.g. for glaucoma treatment drainage implants in general A61M27/002
• CPC Class Codes: A61K 9/0051 Ocular inserts, ocular implants
• CPC Class Codes: A61M 2207/00 Methods of manufacture, assembly or production
• CPC Class Codes: A61M 2210/0612 Eyes
• CPC Class Codes: A61M 29/02 Dilators made of swellable material balloon catheters for angioplasty A61M25/104
• CPC Class Codes: A61M 31/00 Devices for introducing or retaining media, e.g. remedies, in cavities of the body A61M25/00 takes precedence ; introducing or retaining ophthalmic products into the ocular cavities A61F9/0008
• 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
• CPC Class Codes: A61P 27/02 Ophthalmic agents

Abstract

Lacrimal implants and related methods providing secure retention within the lacrimal punctum of an eye are described. The lacrimal implants can comprise a implant body configured for at least partial insertion through the lacrimal punctum and into a lacrimal canaliculus. The implant body can include a deformable retention structure that can be configured to substantially encapsulate an expandable retention element. In some examples, the expandable retention element can include a fluid absorbing material, which can be exposed to fluid such as via a fluid permeable retainer or a fluid permeable aperture. As the fluid absorbing material retains fluid (i.e., upon acceptance of fluid into the retention structure), its size increases and its shape can change to urge one or more portions of the retention structure outward, such as against a wall of the lacrimal canaliculus, thereby securely retaining the lacrimal implant within the punctum.

Claims

1. A lacrimal implant insertable through a lacrimal punctum, the lacrimal implant comprising:

a implant body extending from a proximal end portion to a distal end portion and including a retention structure;

an expandable retention element substantially encapsulated by the retention structure, the expandable retention element configured to expand in at least one direction when the retention structure is implanted in a lacrimal canaliculus; and

wherein the retention structure inhibits the expandable retention element from protruding out of the retention structure during expansion.

2. The lacrimal implant of claim 1, wherein the expandable retention element comprises a fluid absorbing material having an expansion capacity of about 1 time its unexpanded volume.

3. The lacrimal implant of claim 1, wherein the expandable retention element comprises a fluid absorbing material having an expansion capacity of up to about 10 times its unexpanded volume.

4. The lacrimal implant of claim 1, wherein the expandable retention element comprises a substantially non-fluid absorbing material.

5. The lacrimal implant of claim 4, wherein the non-fluid absorbing material includes a shape-memory thermoplastic.

6. The lacrimal implant of claim 4, wherein the non-fluid absorbing material includes an oxide generating system configured to generate and release a plurality of oxides within the retention structure when implanted in the lacrimal canaliculus.

7. The lacrimal implant of claim 1, wherein at least a portion of the retention structure comprises a fluid permeable or hydrophilic material.

8. The lacrimal implant of claim 7, wherein the fluid permeable or hydrophilic material includes at least about 50 wt. % silicone in combination with at least one hydrophilic polymer selected from the group consisting of:

a contact lens material, sodium chloride, polyethylene oxide, polyethylene glycol, polyvinyl pyrilidone, polyvinyl alcohol, and any combination thereof.

9. The lacrimal implant of claim 7, wherein the fluid permeable or hydrophilic material is disposed at a lateral surface exposable to fluid when the retention structure is implanted in the lacrimal canaliculus.

10. The lacrimal implant of claim 1, wherein the retention structure includes a fluid permeable or hydrophilic cap member coupled to the distal end portion of the implant body.

11. The lacrimal implant of claim 10, wherein the cap member includes a tapered distal tip portion configured to facilitate atraumatic insertion through the lacrimal punctum.

12. The lacrimal implant of claim 1, wherein the retention structure inhibits at least about 80% of the expandable retention element from protruding out of the retention structure.

13. The lacrimal implant of claim 1, wherein the retention structure comprises a fluid permeable aperture, the fluid permeable aperture having a size and shape allowing fluid into the retention structure and further inhibiting the expandable retention element from protruding out of the retention structure during expansion.

14. The lacrimal implant of claim 13, wherein the size and shape of the fluid permeable aperture is configured to inhibit the escape of the expandable retention element such that expulsion thereof is limited to less than 5% of an expanded retention element volume.

15. The lacrimal implant of claim 13, wherein the size and shape of the fluid permeable aperture comprises a diameter up to about 0.3 millimeters.

16. The lacrimal implant of claim 13, comprising an aperture membrane configured to cover the fluid permeable aperture, the aperture membrane disposed on an interior or an exterior of the retention structure and having a molecular weight of 10,000 daltons or less.

17. The lacrimal implant of claim 1, comprising a drug core disposed at least partially at or near the proximal end portion of the implant body.

18. The lacrimal implant of claim 17, wherein the drug core includes at least one therapeutic agent inclusion distributed in a solid matrix and at least partially covered by a sheath body to define at least one exposed drug core surface.

19. The lacrimal implant of claim 18, wherein the at least one exposed drug core surface is disposed at or near the proximal end portion of the implant body to contact a tear fluid and release the therapeutic agent over a sustained period when the implant body is inserted through the lacrimal punctum.

20. The lacrimal implant of claim 17, wherein the implant body includes a first chamber configured to house the drug core and a second chamber configured to house the expandable retention element, the second chamber disposed distal of the first chamber.

21. The lacrimal implant of claim 17, comprising a implant body septum positioned between the drug core and the expandable retention element, the septum preventing communication of a material between the drug core and the expandable retention element.

22. The lacrimal implant of claim 1, wherein the proximal end portion of the implant body comprises a first material, and the distal end portion of the implant body including the retention structure comprises a second material different from the first material.

23. The lacrimal implant of claim 1, comprising a implant body projection extending at least partially from or around the proximal end portion of the implant body, and configured to seat against the lacrimal punctum.

24. The lacrimal implant of claim 1, wherein the implant body is configured to be completely insertable through the lacrimal punctum.

25. The lacrimal implant of claim 1, comprising a fluid swellable material disposed on an outer surface portion of the implant body, the fluid swellable material providing secondary retention of the implant body within the lacrimal canaliculus.

26. The lacrimal implant of claim 1, configured in a kit for treating an eye disease, in combination with instructions for using the lacrimal implant to treat an eye disorder.

27. A method of treating a subject having an eye disorder, comprising:

releasing a drug using a lacrimal implant that has been inserted through at least one lacrimal punctum of the subject, the lacrimal implant comprising,

a implant body extending from a proximal end portion to a distal end portion, the implant body including a drug core at or near the proximal end portion and a retention structure at or near the distal end portion,

the drug core comprising an agent and having at least one exposed surface providing release of the agent to the eye,

the retention structure substantially encapsulating an expandable retention element, the expandable retention element configured to expand when the retention structure is implanted in a lacrimal canaliculus; and

wherein the retention structure inhibits the expandable retention element during expansion from protruding out of the retention structure.

28. The method of claim 27, wherein the eye disorder is a glaucoma disease.

29. The method of claim 28, wherein the glaucoma disease is ocular hypertension or primary open angle glaucoma.

30. The method of claim 27, wherein the drug core comprises an anti-glaucoma agent.

31. The method of claim 27, comprising replacing the lacrimal implant that has been inserted with a second lacrimal implant including at least one therapeutic agent inclusion following an interval of time.