Microcapsules for administration of neuroactive agents

• US 6,517,859 B1
• Filed: 06/29/1994
• Issued: 02/11/2003
• Est. Priority Date: 05/16/1990
• Status: Expired due to Fees

• Current Assignee: Brookwood Pharmaceuticals Inc (Surmodics Incorporated)
• Original Assignee: Southwest Research Institute
• Inventors: Tice, Thomas R., Dahlstrom, Annica B., Dillon, Deborah L., Mason, David W., McRae-McFarlane, Amanda
• Primary Examiner(s): AZPURU, CARLOS A
• Application Number:
  US08/268,177
• Time in Patent Office: 3,149 Days
• Field of Search: 424/426, 424/451, 424/490, 424/496, 424/497, 514/963
• US Class Current: 424/426
• CPC Class Codes: A61K 31/135 having aromatic rings , e.g. ketamine, nortriptyline methadone A61K31/137
• CPC Class Codes: A61K 9/0085 Brain, e.g. brain implants; Spinal cord
• CPC Class Codes: A61K 9/1647 Polyesters, e.g. poly(lactide-co-glycolide)
• CPC Class Codes: A61K 9/5068 Cell membranes or bacterial membranes enclosing drugs with additional exogenous lipids A61K9/127; virus envelopes A61K9/5184
• CPC Class Codes: A61P 25/00 Drugs for disorders of the nervous system
• CPC Class Codes: Y10S 977/907 Liposome

Abstract

The present invention relates to polymeric microspheres as injectable, drug-delivery vehicles for use to deliver bioactive agents to sites within the central nervous system, and for the stimulation of nerve fiber growth by implanting such microspheres within the central nervous system of a patient. Microspheres of less than 45 μm, preferably less than about 20 μm, and preferably about 0.1 μm to about 10 μm in mean diameter according to the present invention are also selectively taken-up and into astrocytes when delivered directly into the nervous tissues.

Claims

1. A drug delivery vehicle for administering an effective amount of a neuro-active agent to the central nervous system of an animal in need thereof which comprises a neuro-active agent, other than dopamine, within a microsphere comprising a polymer selected from the group consisting of poly(lactide-co-caprolactone) copolymer, polycaprolactone, and polyhydroxybutyrate-polyhydroxyvalerate copolymer, said polymer (1) being permeable to the neuro-active agent, (2) being biocompatible with the tissues of the central nervous system, and (3) having kinetic characteristics that may be manipulated to allow for the permeation of the neuro-active agent through the polymer at a controlled rate and a predetermined period of time.

2. A drug delivery vehicle according to claim 1, wherein the microsphere comprises the neuro-active agent encapsulated with a polymer that is biodegradable with the tissues of the central nervous system.

3. A method for treating a patient with a neurologic disease or injury by delivering microspheres comprising an encapsulated pharmaceutically-active agent directly into astrocyte cells of the nervous system which comprises the steps of

(A) gaining access to the central nervous system of a patient;

in need of such treatment; and

(B) contacting the astro cells of the central nervous syste with the microspheres comprising an encapsulated pharmaceutically-active agent capable of treating the patient with the neurologic or injury in a therapeutically effective amount to treat the patient with the neurologic disease or injury, within the presence of astrocyte cells, wherein the microspheres are taken up by the astrocyte cells, wherein the microspheres have a diameter of less than about 45 μ

m and comprise a polymer, said polymer (1) being permeable to the pharmaceutically-active agent, (2) being biocompatible with the tissues of the central nervous system, and (3) having kinetic characteristics that may be manipulated to allow for the permeation of the pharmaceutically-active agent through the polymer at a controlled rate and a predetermined period of time,

thereby treating the patient with the neurologic disease or injury by delivery of the microspheres directly into the astrocyte cells of the central nervous system of the patient.

4. A method according to claim 3, wherein the mean diameter of the microspheres is from about 0.1 μ

m to about 20 μ

m.

5. A method according to claim 3, wherein the mean diameter of the microspheres is from about 0.1 μ

m to about 10 μ

m.

6. The method of claim 3, wherein the central nervous system does not include the striatum.

7. The method of claim 3, wherein the contacting step comprises implanting the microspheres into a specific anatomical region of the central nervous system.

8. The method of claim 3, wherein the contacting step comprises implanting the microspheres into a specific anatomical region of the central nervous system other than the striatum.

9. The method of claim 3, wherein the polymer is biodegradable within the tissues of the cantral nervous system.

10. The method of claim 3, wherein the pharmaceutically-active agent comprises a neuroactive molecule.

11. The method of claim 10, wherein the neuroactive molecule comprises a neurotransmitter, a neurotransmitter mimetic, a neuronal receptor agonist, a neuronal receptor antagonist, a neuropeptide, or a neurotrophic factor.

12. The method of claim 10, wherein the neuroactive molecule comprises norepinephrine, ephinephrine, serotonin, dopamine, substance P, somatostatin, nerve growth factor, angiotensin II, corticoptropin releasing factor, choline, acetylcholine, cholinergic neurontrophic agents, basic fibroblast growth factor, acidic fibroblast growth factor, brain derived growth factor, insulin growth factor, transforming growth factor β

, epidermal growth factor, transforming growth factor, glial derived growth factor, estrogen, lithium, gamma amino butyric acid, a gamma aminobutyric acid mimetic, oxytocin, phenethyl amine, or interleukin-1.

13. The method of claim 10, wherein the neuroactive molecule is dopamine or a dopamine mimetic.

14. The method of claim 10, wherein the neuroactive molecule is not dopamine or a dopamine mimetic.

15. The method of claim 3, wherein the polymer comprises a polyesteramide, a polyorthoester, a poly β

-hydroxybutyric acid, a polyanhydride, a polydiene, a polyalkylene, a polymethacrylate, a polyvinyl ether, a polyvinyl alcohol, a polyvinyl chloride, a polyvinyl ester, a polycarbonate, a polyester, a cellulose ether, a cellulose ester, a polysaccharide, a polycaprolactone, or starch.

16. A method according to claim 12, wherein the polymer comprises poly(lactide-co- caprolactone) copolymer, polyhydroxybutyrate-polyhydroxyvalerate copolymer, polybutadiene, polymethyl methacrylate, polyhydroxyethyl methacrylate, polyvinyl acetate, methyl cellulose, hydrxyethyl cellulose, hydroxypropyl methyl cellulose, cellulose acetate, or cellulose acetate butyrate.

17. The method of claim 3 wherein the polymer comprises a poly(lactide-co-glycolide) copolymer, a polylactide homopolymer, or a polyglyoclide homopolymer.

18. The method of claim 3, wherein the microspheres comprise two or more groups of microspheres, wherein each group contains a different neuroactive molecule.

19. The method of claim 3, wherein the pharmaceutically-active agent is dopamine and the polymer is a poly(lactide-co-glycolide)copolymer.

20. The method of claim 3, wherein the pharmaceutically-active agent is dopamine and the polymer is a polycaprolactone.

21. The method of claim 3, wherein the pharmaceutically-active agent is dopamine and the polymer is a polyhydroxybutyrate-polyhydroxyvalerate copolymer.

22. The method of claim 3, wherein the pharmaceutically-active agent is noradrenaline and the polymer is a poly(lactide-co-glycolide) copolymer.

23. The method of claim 3, wherein the pharmaceutically-active agent is from 1% to 80% by weight of the microsphere.

24. The method of claim 3, wherein the treatment is for a patient with a neurologic disease and the neurologic disease is Parkinson'"'"'s disease, amyotrophic lateral sclerosis, Huntington'"'"'s chorea, Alzheimer'"'"'s disease, epilepsy, or tardive dyskinesia.

25. The method of claim 3, wherein the treatment is for a patient with a neurologic injury and the neurologic injury is a spinal cord injury.

26. The method of claim 3, wherein the central nervous system is brain tissue.

27. The method of claim 3, wherein the central nervous system is spinal cord tissue.

28. The method of claim 3, wherein the contacting step is in vivo.

29. A method of making astrocytes that contain misrospheres comprising contacting the astrocytes with the microspheres comprising a pharmaceutically-active agent, wherein the microspheres are taken up by the astrocytes to produce astrocytes that contain microspheres.

30. The method of claim 29, wherein the contacting step is in vivo.

31. The method of claim 29, wherein the contacting step is ex vivo.

32. The method of claim 29, wherein the contacting step is in vitro.

33. A method for treating a patient with a neurologic disease or injury by delivering, into the central nervous system of the patient, astrocytes that contain microspheres comprising an encapsulated pharmaceutically-active agent which comprises the steps of

(A) gaining access to the central nervous system of a patient in need of such treatment;

and

(B) delivering into the central nervous system the astrocytes that contain microspheres comprising an encapsulated pharmaceutically-active agent capable of treating the patient with the neurologic disease or injury in a therapeutically effective amount to treat the patient with the neurologic disease or injury, wherein the microspheres have a diameter of less than about 45 μ

m and comprise a polymer, said polymer (1) being permeable to the pharmaceutically-active agent, (2) being biocompatible with the tissues of the central nervous system, and (3) having kinetic characteristics that may be manipulated to allow for the permeation of the pharamceutically-active agent through the polymer at a controlled rate and a predetermined period of time,

thereby treating the patient with the neurologic disease or injury by delivery of the astrocytes that contain microspheres into the central nervous system of the patient.

34. A method according to claim 33, wherein the mean diameter of the microspheres is from about 0.1 μ

m to about 20 μ

m.

35. A method according to claim 33, wherein the mean diameter of the microspheres is from about 0.1 μ

m to about 10 μ

m.

36. The method of claim 33, wherein the central nervous system does not include the striatum.

37. The method of claim 33, wherein the delivery step comprises delivering the astrocytes that contain microspheres into a specific anatomical region of the central nervous system.

38. The method of claim 33, wherein the delivery step comprises delivering the astrocytes that contain microspheres into a specific anatomical region of the central nervoud system other than the striatum.

39. The method of claim 33, wherein the copolymer is biodegradable within the tissues of the central nervous system.

40. The method of claim 33, wherein the pharmaceutically-active agent comprises a neuroactive molecule.

41. The method of claim 40, wherein the neuroactive molecule comprises a neurotransmitter, a neurotransmitter mimetic, a neuroal receptor agonist, a neuronal receptor antagonist, a neuropeptide, or a neurotrophic factor.

42.The method of claim 40, wherein the neuroactive molecule comprises norepinephrine, epinephrine, serotonin, dopamine, substance P, somatostatin, nerve growth factor, angiotensin II, corticoptropin releasing factor, choline, acetylcholine, cholinergic neurontrophic agents, basic fibroblast growth factor, acidic fibroblast growth factor, brain derived growth factor, insulin growth factor, transforming growth factor β , epidermal growth factor, transforming growth factor, glial derived growth factor, estrogen, lithium, gamma amino butyric acid, a gamma aminobutyric acid mimetic, oxytocin, phenethyl amine, or interleukin-1.

42. The method of claim 40, wherein the neuroactive molecule is dopamine or a dopamine mimetic.

43. The method of claim 40, wherein the neuroactive molecule is not dopamine or a dopamine mimetic.

44. The method of claim 33, wherein the polymer comprises a polyesteramide, a polyorthoester, a poly β

-hydroxybutyric acid, a polyanhydride, a polydiene, a polyalkylene, a polymethacrylate, a polyvinyl ether, a polyvinyl alcohol, a polyvinyl chloride, a polyvinyl ester, a polycarbonate, a polyester, a cellulose ether, a cellulose ester, a polysaccharide, a polycaprolactone, or starch.

45. A method according to claim 33, wherein the polymer comprises poly(lactide-co- caprolactone) copolymer, polyhydroxybutyrate-polyhydroxyvalerate copolymer, polybutadiene, polymethyl methacrylate, polyhydroxyethyl methacrylate, polyvinyl acetate, methyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, cellulose acetate, or cellulose acetate butyrate.

46. The method of claim 33, wherein the polymer comprises a poly(lactide-co-glycolide) copolymer, a polylactide homopolymer, or a polyglycolide homopolymer.

47. The method of claim 33, wherein the microspheres comprise two or more groups of microspheres, wherein each group contains a different neuroactive molecule.

48. The method of claim 33, wherein the pharmaceutically-active agent is dopamine and the polymer is a poly(lactide-co-glycolide) copolymer.

49. The method of claim 33, wherein the pharmaceutically-active agent is dopamine and the polymer is a polycaprolactone.

50. The method of claim 33, wherein the pharmaceutically-active agent is dopamine and the polymer is a polyhydroxybutyrate-polyhydroxyvalerate copolymer.

51. The method of claim 33, wherein the pharmaceutically-active agent is noradrenaline and the polymer is a poly(lactide-co-glycolide) copolymer.

52. The method of claim 33, wherein the pharmaceutically-active agent is from 1% to 80% by weight of the microsphere.

53. The method of claim 33, wherein the treatment is for a patient with a neurologic disease and the neurologic disease is Parkinson'"'"'s disease, amyotrophic lateral sclerosis, Huntington'"'"'s chorea, Alzheimer'"'"'s disease, epilepsy, or tardive dyskinesia.

54. The method of claim 33, wherein the treatment is for a patient with a neurologic injury and the neurologic injury is a spinal cord injury.

55. The method of claim 33, wherein the central nervous system is brain tissue.

56. The method of claim 33, wherein the central nervous system is spinal cord tissue.