Sustained release of agents for localized pain management

• US 20080220062A1
• Filed: 10/23/2007
• Published: 09/11/2008
• Est. Priority Date: 10/23/2006
• Status: Abandoned Application

• Current Assignee: pSivida US, Inc
• Original Assignee: PSivida Inc.
• Inventors: Ashton, Paul
• Application Number:
  US11/977,148
• Publication Number:
  US 20080220062A1
• Time in Patent Office: Days
• US Class Current: 424/484
• CPC Class Codes: A61K 9/0014 Skin, i.e. galenical aspects of topical compositions non-active ingredients are additionally classified in A61K47/00; A61K9/0009, A61K9/0021, A61K9/7015, A61K9/7023 take precedence; cosmetic preparations A61K8/00, A61Q; preparations for wound dressings or bandages A61L26/00
• CPC Class Codes: A61K 9/0019 Injectable compositions; Intramuscular, intravenous, arterial, subcutaneous administration; Compositions to be administered through the skin in an invasive manner non-active ingredients are additionally classified in A61K47/00
• CPC Class Codes: A61K 9/0024 Solid, semi-solid or solidifying implants, which are implanted or injected in body tissue compositions for intravenous administration, normal injectable solutions or dispersions for, e.g. subcutaneous administration A61K9/0019; brain implants A61K9/0085; (coated) prostheses, catheters or stents A61L
• CPC Class Codes: A61K 9/0031 Rectum, anus
• CPC Class Codes: A61K 9/006 Oral mucosa, e.g. mucoadhesive forms, sublingual droplets; Buccal patches or films; Buccal sprays
• CPC Class Codes: A61P 25/00 Drugs for disorders of the nervous system

Abstract

The invention relates to the treatment of localized pain by providing sustained release of an agent suitable for treating pain, methods for preparing and administering the agent, and methods of formulating and administering the agent as a pharmaceutical preparation. The agent can be locally administered to reduce systemic concentrations of the agent.

Claims

1. A sustained-release formulation comprising at least one pain-relief agent having a blood plasma half-life of less than about 15 minutes under physiological conditions, said formulation being adapted for local delivery.

2. The formulation of claim 1, wherein a concentration of the at least one agent in a patient'"'"'s blood plasma remains less than about 10 ng/ml when administered to said patient.

3. The formulation of claim 1, wherein a concentration of the at least one agent in a patient'"'"'s blood plasma is less than a therapeutic concentration normally required for a systemic effect of the at least one agent.

4. The formulation of claim 1, wherein the at least one agent is in a dose of more than 75 ug/kg body weight of a patient to whom the at least one agent is administered.

5. The formulation of claim 1, wherein release of the at least one agent occurs over a period of at least 3 hours.

6. The formulation of claim 1, wherein the at least one agent is administered in a polymer matrix.

8. The formulation of any of claims 1-7, wherein the formulation is affixed to a drug delivery device.

9. The formulation of any of claims 1-7, wherein the at least one agent is a short-acting opioid or an active metabolite of an opioid.

10. The formulation of any of claims 1-7, wherein more than one pain-relief agent is delivered.

11. The formulation of any of claims 1-7, wherein the at least one agent does not trigger a centrally mediated analgesic response when applied to a body.

12. The formulation of any of claims 1-7, wherein the at least one agent gives rise to at least one reduced side effect when compared to the side effects produced by the at least one agent delivered by standard commercial systems.

7. A sustained release formulation comprising at least one pain relief agent having a blood plasma half life of less than about 15 minutes, the agent having an aqueous solubility of less than about 5 mg/ml, said formulation being adapted for local delivery.

13. A method for treating a patient experiencing pain, comprising:

providing a sustained-release formulation having at least one pain-relief agent in a polymer matrix, said at least one agent having a blood-plasma elimination half-life of less than about 15 minutes under physiological conditions; and

locally delivering said sustained-release formulation to the patient.

14. The method of claim 13, wherein the at least one agent'"'"'s concentration remains less than about 10 ng/ml in the patient'"'"'s blood plasma.

15. The method of claim 13, wherein sustained release of the at least one agent occurs over a period of at least 3 hours.

16. The method of claim 13, wherein a concentration of the at least one agent in a patient'"'"'s blood plasma remains less than a therapeutic concentration normally required for a systemic effect of the at least one agent.

17. The method of claim 13, further comprising applying a dose of the at least one agent of more than 75 ug/kg body weight of the patient.

18. The method of claim 13, further comprising administering the at least one agent in a polymer matrix.

19. The method of any of claims 13-18, further comprising affixing the formulation to a drug delivery device.

20. The formulation of any of claims 13-18, wherein the at least one agent is a short-acting opioid or an active metabolite of a short-acting opioid.

21. The method of any of claims 13-18, wherein more than one pain-relief agent is delivered.

22. The method of any of claims 13-18, wherein the at least one agent does not trigger a centrally mediated analgesic response in the patient.

23. The method of any of claims 13-18, wherein the at least one agent gives rise to at least one reduced side effect when compared to the side effects produced by the at least one agent delivered by a standard commercial system.

25. The method of any of claims 13-18 or 24, wherein the at least one agent has a blood-plasma elimination half-life of less than about 10 minutes.

24. A method for treating a patient experiencing pain, comprising:

providing a sustained-release formulation having at least one short-acting opioid in a polymer matrix, wherein the sustained-release of the opioid occurs over a period of at least three hours, and wherein the opioid has a systemic concentration sufficiently low to avoid triggering a centrally-mediated analgesic response in the patient, and locally delivering said sustained-release formulation to said patient.