Non-biodegradable stent comprising a biodegradable coating and method of coating the same

Patent metadata

Field	Value
Publication number	US-9987399-B2
Application number	US-74063808-A
Country	US
Kind code	B2
Filing date	Oct 30, 2008
Priority date	Oct 30, 2007
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

The present invention relates to the field of non-biodegradable stents, and therein to non-biodegradable stents coated with at least one layer of a biodegradable polymer which maintains mechanical integrity of the coating both in storage and upon balloon expansion and which can optionally release drugs. The at least one polymer layer comprises a biodegradable polymer and a plasticizer. The present invention also relates to a manufacturing method of such a non-biodegradable stent.

First claim

The invention claimed is:

1. A non-biodegradable stent comprising a biodegradable coating wherein said coating comprises one or more polymer layers comprising a biodegradable polymer and a plasticizer selected from the group consisting of triethyl citrate (TEC), a polyalkylene glycol, propylene glycol (PG) glycerol, di-2-ethylhexyladipate, di-2-ethylhexylphthalate, dicyclohexylphthalate, diisononyladipate, diisononylphthlate, n-butyl benzyl phthalate, and glycerol, wherein the plasticizer is contained in the one or more polymer layers in an amount from 1-30 wt %, based on dry weight of the one or more polymer layers, and wherein said coating comprises a drug combination of (i) triflusal and sirolimus or (ii) triflusal and a sirolimus derivative, the drug combination being present in an amount of about 0.1-35 wt %, based on dry weight of the drug containing layer.

2. The non-biodegradable stent of claim 1 , wherein the non-degradable stent is made of a material selected from a metal, a metal alloy, and a biostable polymer.

3. The non-biodegradable stent of claim 2 , wherein the alloy is a stainless steel or a cobalt chromium alloy.

4. The non-biodegradable stent of claim 1 , wherein the biodegradable polymer coating is made of a single polymer layer comprising a biodegradable polymer and a plasticizer.

5. The non-biodegradable stent of claim 4 , wherein the biodegradable polymer is selected from the group of poly(L-lactide) (PLLA), polycaprolactone (PCL), a copolymer of polycaprolactone (PCL) and polylactic acid (PLA) having an lactic acid content of 5-60%, a copolymer of poly(lactide) and poly(glycolide) (PLGA) having an glycolide content of 5-50%.

6. The non-biodegradable stent of claim 4 , wherein the plasticizer is triethyl citrate.

7. The non-biodegradable stent of claim 4 , wherein the plasticizer is contained in the polymer layer in an amount from 1-30 wt %, based on the dry weight of the polymer layer.

8. The non-biodegradable stent of claim 4 , wherein the polymer is a PLGA copolymer and the plasticizer is contained in an amount from 2-15 wt %, based on the dry weight of the polymer layer.

9. The non-biodegradable stent of claim 4 , wherein the polymer layer is made of a material having a glass transition temperature (Tg) in the range of about 10-40° C.

10. The non-biodegradable stent of claim 4 , wherein the polymer layer is made of a material having an elongation at break in the range of more than 150% to less than 1000%.

11. The non-biodegradable stent of claim 1 , wherein the biodegradable polymer coating comprises
(i) a first polymer layer comprising a biodegradable polymer and a plasticizer, and
(ii) a second polymer layer comprising a biodegradable polymer.

12. The non-biodegradable stent of claim 11 , wherein the second polymer layer further comprises a plasticizer.

13. The non-biodegradable stent of claim 11 , wherein the biodegradable polymer of the first polymer layer is selected from the group of poly(L-lactide) (PLLA), polycaprolactone (PCL), a copolymer of polycaprolactone (PCL) and polylactic acid (PLA) having an lactic acid content of 5-60%, a copolymer of poly(lactide) and poly(glycolide) (PLGA) having an glycolide content of 5-50%.

14. The non-biodegradable stent of claim 11 , wherein the biodegradable polymer of the second polymer layer is selected from the group of poly(L-lactide) (PLLA), polycaprolactone (PCL), a copolymer of polycaprolactone (PCL) and polylactic acid (PLA) having an lactic acid content of 5-60%, or a copolymer of poly(lactide) and poly(glycolide) (PLGA) having an glycolide content of 5-50%.

15. The non-biodegradable stent of claim 11 , wherein the plasticizer in the first and/or second polymer layer is triethyl citrate.

16. The non-biodegradable stent of claim 11 , wherein the plasticizer is contained in the first polymer layer in an amount from about 1-30 wt % and in the second polymer layer in an amount of less than about 30 wt %, based on the dry weight of the respective first or second polymer layers.

17. The non-biodegradable stent of claim 11 , wherein in the first polymer layer the polymer is a PLGA copolymer, and the plasticizer is contained in this layer in an amount from 2-15 wt %, based on the dry weight of the first polymer layer.

18. The non-biodegradable stent claim 11 , wherein in the second polymer layer the polymer is a PLGA copolymer, and the plasticizer is contained in this layer in an amount from 2-10 wt %, based on the dry weight of the second polymer layer.

19. The non-biodegradable stent of claim 11 , wherein in the second polymer layer the polymer is a PLLA, and the plasticizer is contained in this layer in an amount from 2-20 wt %, based on the dry weight of the second polymer layer.

20. The non-biodegradable stent of claim 11 , wherein the polymer coating further comprises a topcoat layer comprising a biodegradable polymer.

21. The non-biodegradable stent of claim 1 , wherein the amount of triflusal is about 1-15 wt % and the amount of sirolimus or a sirolimus derivative is about 1-15 wt %, based on dry weight of the drug combination containing layer.

22. The non-biodegradable stent of claim 11 , wherein the first and second polymer layer is made of a material having a glass transition temperature (Tg) in the range of 10-40° C.

23. The non-biodegradable stent of claim 11 , wherein the first and second polymer layer is made of a material having an elongation at break in the range of more than 150% to less than 1000%.

24. The non-biodegradable stent of claim 20 , wherein the biodegradable polymer in the topcoat layer is selected from the group of poly(L-lactide) (PLLA), polycaprolactone (PCL), a copolymer of polycaprolactone (PCL) and polylactic acid (PLA) having an lactic acid content of 5-60%, a copolymer of poly(lactide) and poly(glycolide) (PLGA) having an glycolide content of 5-50%.

25. The non-biodegradable stent of claim 20 , wherein the topcoat layer further comprises a plasticizer.

26. The non-biodegradable stent of claim 25 , wherein the plasticizer is selected from the group consisting of triethyl citrate (TEC), a polyalkylene glycol, propylene glycol (PG) glycerol, di-2-ethylhexyladipate (dioctyladipate), di-2-ethylhexylphthalate (dioctylphthalate), dicyclohexylphthalate; diisononyladipate; diisononylphthlate; n-butyl benzyl phthalate.

27. The non-degradable stent of claim 1 , wherein the drug combination is loaded into a single polymer layer or the first and/or second and/or any further polymer layers.

28. The non-biodegradable stent of claim 1 , wherein the overall coating thickness ranges from about 5-30 microns.

Assignees

• Venkatraman Subramanian
• Boey Yin Chiang
• Khanolkar Laxmikant
• Univ Nanyang Tech

Inventors

• Venkatraman Subramanian
• Boey Yin Chiang
• Khanolkar Laxmikant

Classifications

• A61F2/91

  made from perforated sheets or tubes, e.g. perforated by laser cuts or etched holes · CPC title

• A61L31/141 Primary

  Plasticizers · CPC title

• A61L2420/08

  Coatings comprising two or more layers · CPC title

• C08L67/04

  Polyesters derived from hydroxycarboxylic acids, e.g. lactones (C08L67/06 takes precedence) · CPC title

• A61F2310/0097

  Coating or prosthesis-covering structure made of pharmaceutical products, e.g. antibiotics · CPC title