Controlled release microencapsulated NGF formulation

• US 20030203040A1
• Filed: 05/20/2003
• Published: 10/30/2003
• Est. Priority Date: 06/13/1997
• Status: Active Grant

• Current Assignee: Eileen T. Duenas, Jeffrey L. Cleland, Xanthe M. Lam
• Original Assignee: Eileen T. Duenas, Jeffrey L. Cleland, Xanthe M. Lam
• Inventors: Lam, Xanthe M., Cleland, Jeffrey L., Duenas, Eileen T.
• Granted Patent: US 7,163,701 B2
• Time in Patent Office: Days
• US Class Current: 424/490
• CPC Class Codes: A61K 38/185 Nerve growth factor [NGF]; Brain derived neurotrophic factor [BDNF]; Ciliary neurotrophic factor [CNTF]; Glial derived neurotrophic factor [GDNF]; Neurotrophins, e.g. NT-3
• CPC Class Codes: A61K 9/1647 Polyesters, e.g. poly(lactide-co-glycolide)
• CPC Class Codes: C07K 14/48 Nerve growth factor [NGF]

Abstract

NGF microencapsulation compositions having controlled release characteristics, preferably with increased stability, for the NGF component, particularly human recombinant NGF (“rhNGF”) are provided that yield enhanced stability of NGF for use in promoting nerve cell growth, repair, survival, differentiation, maturation or function. Methods for making and using such compositions are also provided.

Claims

1. A method of making a microsphere device for controlled sustained release of NGF having a decreased NGF aggregation characteristic, comprising mixing NGF in solution with an NGF-stabilizing metal salt of a metal that binds NGF, wherein the molar ratio of NGF to metal is 1 to 4 to 1 to 50, and microencapsulating the NGF-metal mixture to form a microsphere containing NGF and metal capable of controlled sustained release of NGF.

2. The method of claim 1, wherein the molar ratio of NGF to metal in the solution is 1 to 6 to 1 to 20.

3. The method of claim 2, wherein the molar ratio of NGF to metal in the solution is 1 to 8 to 1 to 14.

4. The method of claim 2, wherein the metal is an alkali metal, alkaline earth metal, or polyvalent metal.

5. The method of claim 4, wherein the metal is sodium, potassium, calcium, magnesium, iron II, iron III, copper II, tin II, tin IV, aluminum II, aluminum III, or zinc.

6. The method of claim 4, wherein the metal is zinc.

7. The method of claim 1, wherein the metal is in an aliphatic carboxylic acid salt form.

9. The method of claim 7, wherein the salt is a carbonate or acetate salt.

10. The method of claim 1, wherein the metal salt is zinc chloride, zinc bromide, zinc iodide, zinc fluoride, zinc sulfate, zinc nitrate, zinc thiocyanate, zinc carbonate, zinc acetate, zinc glycolate, zinc lactate, zinc tartrate, zinc benzoate, zinc salicylate, zinc phenolsulfonate, calcium chloride, calcium bromide, calcium iodide, calcium fluoride, calcium sulfate, calcium nitrate, calcium thiocyanate, calcium carbonate, calcium acetate, calcium propionate, calcium oxalate, calcium tartrate, calcium lactate, calcium citrate, calcium gluconate, calcium benzoate, or calcium salicylate.

11. The method of claim 10, wherein the metal salt is zinc acetate, zinc carbonate, calcium acetate, or calcium carbonate.

12. The method of claim 1, wherein the NGF is human 118 NGF.

13. The method of claim 1, wherein the NGF is secreted from Chinese hamster ovary cells.

14. The method of claim 1 wherein the mixture is pH 6 to 8.

15. The method of claim 1, further comprising admixing a polyol stabilizer having a molecular weight of less than about 70,000 kD.

16. The method of claim 15, wherein the polyol is a sugar alcohol.

17. The method of claim 16, wherein the sugar is trehalose, mannitol, or sucrose.

18. The method of claim 1, wherein microencapsulation comprises admixing a biodegradable polymer with the NGF-metal mixture, and formulating the mixture into polymeric microspheres.

19. The method of claim 18, further comprising drying the NGF-metal solution prior to admixing with the biodegradable polymer.

20. The method of claim 18, further comprising admixing a release modifier into the dried NGF-metal mixture or NGF-biodegradable polymer mixture.

21. The method of claim 1, wherein the microencapsulation comprises drying the NGF-metal solution, dispersing a biodegradable polymer in an organic solvent, admixing the dried NGF mixture with the biodegradable polymer organic solvent mixture, spraying the NGF-biodegradable polymer mixture to form droplets, removing the organic solvent from the droplets to form microspheres containing NGF.

22. The method of claim 21, which further comprises admixing a release modifier with the dried NGF-metal mixture.

23. The method of claim 21, wherein the organic solvent is ethyl acetate or methylene chloride.

24. The method of claim 1, wherein the microspheres are 1 to 1000 microns.

25. The method of claim 1, wherein the NGF is 5 to 20% by weight in the microsphere.

26. The method of claim 1, wherein the biodegradable polymer is polylactide or poly(lactide-co-glycolide).

27. The method of claim 1, further comprising compressing the microspheres to form a pellet.

28. A method for administering NGF, comprising administering to a patient in need of treatment a biocompatible polymeric microsphere, having a diameter of less than 300 microns, containing 0.1 to 50% NGF by weight and a metal complexed to NGF, wherein a therapeutically effective amount of NGF is released from the microspheres over a period of time in excess of one day.

29. The method of claim 28, wherein the metal is zinc, calcium or magnesium.

30. The method of claim 28, wherein the patient suffers from peripheral neuropathy.

31. A polymeric microsphere device having a diameter of less than 1000 microns for sustained controlled release of NGF, comprising a biocompatible polymeric microsphere containing 0.1 to 50% NGF by weight complexed with an NGF-stabilizing metal that binds NGF, which device is capable of releasing NGF over a period of time in excess of one day.

32. A method of increasing the stability of NGF in a microencapsulated composition containing NGF as active principle, comprising incorporating an NGF-stabilizing and binding metal into an NGF aqueous solution prior to drying the solution for microencapsulation.