Biodegradable injectable implants and related methods of manufacture and use

• US 20030093157A1
• Filed: 06/28/2002
• Published: 05/15/2003
• Est. Priority Date: 06/29/2001
• Status: Active Grant

• Current Assignee: Medgraft Microtech, Inc.
• Original Assignee: Medgraft Microtech, Inc.
• Inventors: Casares, Crisoforo Peralta, DʼLagarde, Danel Leon
• Granted Patent: US 7,314,636 B2
• Time in Patent Office: Days
• US Class Current: 623/23.73
• CPC Class Codes: A61L 2400/06 Flowable or injectable implant compositions
• CPC Class Codes: A61L 27/48 with macromolecular fillers
• CPC Class Codes: C08L 67/04 Polyesters derived from hydroxycarboxylic acids, e.g. lactones C08L67/06 takes precedence

Abstract

This invention is directed to the field of medical implants, and more specifically to biodegradable injectable implants and their methods of manufacture and use. The injectable implants disclosed herein comprise glycolic acid and bio-compatible/bio-absorbable polymeric particles containing a polymer of lactic acid. The particles are small enough to be injected through a needle but large enough to avoid engulfment by macrophages. The injectables of this invention may be in a pre-activated solid form or an activated form (e.g., injectable suspension or emulsion).

Claims

1. A biodegradable, injectable implant comprising glycolic acid and particles comprised of a polymer comprising lactic acid repeats units, wherein the particles have a diameter of from about 20μ

to about 120μ

.

2. The implant of claim 1, wherein the particles have a diameter of from about 40μ

to about 80μ

.

3. The implant of claim 2, wherein the particles have a mean diameter of from about 50μ

to about 70μ

.

4. The implant of claim 1, wherein the implant further comprises a suspension of the particles in a pharmaceutically acceptable carrier.

5. The implant of claim 4, wherein the pharmaceutically acceptable carrier comprises water, saline, starch, hydrogel, polyvinylpyrrolidone, polysaccharide, hyaluronic acid ester, or plasma.

6. The implant of claim 4, wherein the polymer is present in a concentration of from about 30 mg to about 40 mg of polymer per 100 ml of the pharmaceutically acceptable carrier.

7. The implant of claim 6, wherein the polymer is present in a concentration of from about 35 mg to about 38 mg per 100 ml of the pharmaceutically acceptable carrier.

8. The implant of claim 4, wherein the glycolic acid is present in a concentration of from about 1.8 mcg to about 18.2 mcg GA per 100 ml of the pharmaceutically acceptable carrier.

9. The implant of claim 8, wherein the glycolic acid is present in a concentration of from about 11 mcg to 14 mcg per 100 ml of the pharmaceutically acceptable carrier.

10. The implant of claim 1 further comprising a gelling agent.

11. The implant of claim 10, wherein the gelling agent comprises a cellulose derivative or a pharmaceutically acceptable acid or ester.

12. The implant of claim 11, wherein the cellulose derivative comprises hydroxypropylmethylcellulose or carboxymethylcellulose.

13. The implant of claim 11, wherein the pharmaceutically acceptable acid or ester is selected from the group consisting of a synthetic hyaluronic acid, a lactic acid ester, sodium carmellose, and a caproic acid ester.

14. The implant of claim 1 further comprising a surfactant.

15. The implant of claim 14, wherein the surfactant comprises a polyoxyethylene sorbitan, a polysorbate or pluronic acid.

16. The implant of claim 15, wherein the polyoxyethylene sorbitan comprises polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan tristearate, polyoxyethylene sorbitan monopalmitate, or polyoxyethylene sorbitan monolaurate.

17. The implant of claim 1, wherein the polymer comprises a homopolymer of lactic acid.

18. The implant of claim 17, wherein the polymer comprises poly-l-lactic acid or poly-d,l-lactic acid.

19. The implant of claim 1, wherein the polymer comprises a co-polymer of lactic acid.

20. The implant of claim 19, wherein the polymer comprises a co-polymer of lactic acid and glycolic aid.

21. The implant of claim 19, wherein the polymer comprises repeat units capable of forming crosslinks.

22. The implant of claim 19, wherein the polymer comprises at least one lactone repeat unit.

23. The implant of claim 1, wherein the polymer has an intrinsic viscosity of from about 3.5 to about 3.8 dl/g.

24. The implant of claim 1, wherein the polymer has a molecular weight of from about 150,00 to about 220,000 Daltons.

25. The implant of claim 24, wherein the polymer has a molecular weight of from about 165,00 to 180,000 Daltons.

26. The implant of claim 25, wherein the polymer has a melting point ranging from about 170 to about 200°

C.

27. The implant of claim 1 further comprising a cryoprotecting agent.

28. The implant of claim 27, wherein the cryoprotecting agent comprises d-mannitol, lactose, sucrose, fructose, a sugar, a carbohydrate, or dextran.

29. The implant of claim 1 further comprising a buffering agent.

30. The implant of claim 29, wherein the buffering agent comprises a phosphate buffer or a citrate buffer.

31. The implant of claim 1, wherein the implant is in a ready for use prefilled sterile syringe.

32. The implant of claim 1, wherein the implant is in a vial in the form of a sterile suspension.

33. The implant of claim 1, wherein the implant is in the form of a lyophilized powder.

34. The implant of claim 33, wherein the powder comprises from about 0.002% to about 0.02% glycolic acid by weight.

35. The implant of claim 34, wherein the powder comprises from about 0.01% to about 0.02% glycolic acid by weight.

36. The implant of claim 33, wherein the powder comprises from about 36% to about 45% polymer by weight.

37. The implant of claim 36, wherein the powder comprises from about 40% to about 41% polymer by weight.

38. The implant of claim 1, wherein the implant is in a two-compartment prefilled syringe, wherein one compartment contains a freeze-dried powder and the other compartment contains a pharmaceutically acceptable carrier.

39. The implant of claim 1, wherein the implant has been sterilized by gamma or E-beam irradiation or exposure to ethylene oxide gas.

40. The implant of claim 1 farther comprising a medicament.

41. The implant of claim 40, wherein the medicament comprises a peptide, a tissue regeneration agent, an anesthetic, an antibiotic, a steroid, fibronectin, a cytokine, a growth factor, an analgesic, an antiseptic, alpha-, beta, or gamma-interferon, erythroietin, glucagons, calcitonin, heparin, interleukin-1, interleukin-2, filgrastim, cDNA, DNA, PROTEINS, PEPTIDES, HGH, luteinizing hormone, atrial natriuretic factor, Factor VIII, Factor IX, or follicle-stimulating hormone.

42. The implant of claim 41, wherein the medicament comprises an anesthetic which is selected from the group consisting of lidocaine, xylocaine, novocaine, benzocaine, prilocaine, ripivacaine, and propofol.

43. A biodegradable, injectable implant comprising glycolic acid and particles comprised of polylactic acid, wherein the particles have a mean diameter of from about 40μ

to about 80μ

.

44. The implant of claim 43, wherein the particles have a mean diameter of from about 55 to about 65μ

.

45. The implant of claim 43, wherein the polylactic acid comprises poly-l-lactic acid or poly-d,l-lactic acid, or co-polylactide-polyglycolide.

46. The implant of claim 43, wherein the polylactic acid has an intrinsic viscosity of from about 3.6 to about 3.8 dl/g.

47. The implant of claim 43, wherein the polylactic acid has a molecular weight as determined by viscosity from about 150,000 to about 180,000 Daltons.

48. The implant of claim 43, wherein the implant further comprises a suspension of the particles in a pharmaceutically acceptable carrier.

49. The implant of claim 48, wherein the pharmaceutically acceptable carrier comprises water.

50. The implant of claim 49, wherein the pharmaceutically acceptable carrier comprises saline, starch, hydrogel, polyvinylpyrrolidone, polysaccharide, hyaluronic acid ester, or plasma.

51. The implant of claim 49, wherein the polylactic acid is present in a concentration of from about 30 mg to about 40 mg of polymer per 100 ml of the pharmaceutically acceptable carrier.

52. The implant of claim 49, wherein the glycolic acid is present in a concentration of from about 1.8 mcg to about 18.2 mcg GA per 100 ml of the pharmaceutically acceptable carrier.

53. The implant of claim 43 further comprising a gelling agent.

54. The implant of claim 53, wherein the gelling agent comprises a cellulose derivative or a pharmaceutically acceptable acid or ester.

55. The implant of claim 54, wherein the cellulose derivative comprises hydroxypropylmethylcellulose or carboxymethylcellulose.

56. The implant of claim 54, wherein the pharmaceutically acceptable acid or ester comprises a synthetic hyaluronic acid, a lactic acid ester, sodium carmellose, or a caproic acid ester.

57. The implant of claim 43 further comprising a surfactant.

58. The implant of claim 57, wherein the surfactant comprises a polyoxyethylene sorbitan, a polysorbate or pluronic acid.

59. The implant of claim 58, wherein the polyoxyethylene sorbitan comprises polyoxyethylene sorbitan monooleate, polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan tristearate, polyoxyethylene sorbitan monopalmitate, or polyoxyethylene sorbitan monolaurate.

60. The implant of claim 43 further comprising a cryoprotecting agent.

61. The implant of claim 60, wherein the cryoprotecting agent comprises d-mannitol, lactose, sucrose, fructose, or dextran.

62. The implant of claim 43 further comprising a buffering agent.

63. The implant of claim 62, wherein the buffering agent comprises a sodium phosphate or a citrate buffer.

64. The implant of claim 43, wherein the implant is in a ready for use prefilled sterile syringe.

65. The implant of claim 43, wherein the implant is in a vial in the form of a sterile suspension.

66. The implant of claim 43, wherein the implant is in the form of a lyophilized powder.

67. The implant of claim 66, wherein the powder comprises from about 0.002% to about 0.02% glycolic acid by weight.

68. The implant of claim 67, wherein the powder comprises from about 36% to about 45% polymer by weight.

69. The implant of claim 43 further comprising a medicament selected from the group consisting of an anesthetic, a peptide, a tissue regeneration agent, an antibiotic, a steroid, fibronectin, a cytokine, a growth factor, an analgesic, an antiseptic, alpha-, beta, or gamma-interferon, erythroietin, glucagons, calcitonin, heparin, interleukin-1, interleukin-2, filgrastim, cDNA, DNA, PROTEINS, PEPTIDES, HGH, luteinizing hormone, atrial natriuretic factor, Factor VIII, Factor IX, and follicle-stimulating hormone.

70. A biodegradable, injectable implant comprising:

a) glycolic acid;

b) particles of polylactic acid, wherein the particles have a mean diameter of from about 40μ

to about 80μ

;

c) a gelling agent;

d) a surfactant;

e) a cryoprotecting agent; and

f) a buffering agent, wherein the implant comprises an aqueous suspension of particles of the polylactic acid.

71. The implant of claim 70, wherein the polylactic acid is poly-l-lactic acid or poly-l,d-lactic acid.

72. The implant of claim 70, wherein the polylactic acid a molecular weight of from about 160,00 to about 180,000 Daltons.

73. The implant of claim 70, wherein the polylactic acid is present in a concentration of from about 30 mg to about 40 mg of polymer per 100 ml of suspension.

74. The implant of claim 70, wherein the glycolic acid is present in a concentration of from about 12 mcg to about 13 mcg GA per 100 ml of suspension.

75. The implant of claim 70, wherein the gelling agent comprises hydroxypropylmethylcellulose or carboxymethylcellulose.

76. The implant of claim 70, wherein the surfactant comprises a polyoxyethylene sorbitan.

77. The implant of claim 70, wherein the cryoprotecting agent comprises d-mannitol.

78. A method of making a biodegradable, injectable implant comprising:

a) pulverizing a polymer comprising lactic acid repeat units to a first powder;

b) cold micronizing the first powder to form particles having a mean diameter of from about 40μ

to about 80μ

;

c) forming an emulsion comprising the particles;

d) obtaining a solution which comprises glycolic acid;

e) mixing the emulsion and solution during heating to obtain an aqueous slurry;

f) drying the aqueous slurry to obtain a second powder; and

g) lyophilizing the second powder.

79. The method of claim 78, wherein the polymer comprises a homo- or co-polymer of polylactic acid.

80. The method of claim 78, wherein the solution further comprises a gelling agent, a surfactant, a cryoprotecting agent or a buffering agent.

81. The method of claim 78 further comprising forming a suspension of the second powder in a pharmaceutically acceptable carrier.

82. A method for soft tissue augmentation comprising injecting a mammal at an injection site in need of such soft tissue augmentation a bulking agent comprising glycolic acid and polymeric particles comprising lactic acid repeat units, wherein the particles have a mean diameter of from about 40μ

to about 80μ

.

83. The method of claim 82, wherein the mammal is a human.

84. The method of claim 82 wherein the injection site is a congenital anomaly, a scar or a wrinkle.

85. The method of claim 82, wherein the bulking agent is used to augment facial fat loss in the human.

86. The method of claim 82, wherein the bulking agent is used to treat a sphincter deficiency or erectile dysfunction.

87. The method of claim 82, wherein the injection site is a tissue defining a vocal cord.

88. A method for improving the appearance of a wrinkle on a human comprising injecting glycolic acid into the human at the wrinkle.