Microparticles for selectively targeted hyperthermia

• US 20060147381A1
• Filed: 01/22/2004
• Published: 07/06/2006
• Est. Priority Date: 01/22/2003
• Status: Abandoned Application

• Current Assignee: Sirtex Medical Limited
• Original Assignee: Sirtex Medical Limited
• Inventors: Rutherford, Katrina Francis, Jones, Stephen Keith, Gray, Bruce Nathaniel, Ruys, Andrew John
• Application Number:
  US10/543,063
• Publication Number:
  US 20060147381A1
• Time in Patent Office: Days
• US Class Current: 424/9.323
• CPC Class Codes: A61K 41/0052 Thermotherapy; Hyperthermia; Magnetic induction; Induction heating therapy
• CPC Class Codes: A61K 9/14 Particulate form, e.g. powders, Processes for size reducing of pure drugs or the resulting products, Pure drug nanoparticles microspheres A61K9/16; microcapsules A61K9/50; nanocapsules, nanoparticles of the matrix type A61K9/51
• CPC Class Codes: A61N 1/406 using implantable thermoseeds or injected particles for localized hyperthermia preparations of seeds and particles A61K41/0052
• CPC Class Codes: A61N 2/004 specially adapted for a specific therapy

Abstract

A microparticle composition(s) comprising nanomagnetic particles and a matrix, wherein said microparticle composition(s) have a least one of the following properties: (a) a VAR of at least about 1 Watts/cm3 subject to appropriate field conditions; (b) a density of about 2.7 or less: or (c) a size of about 100 nm to about 200 microns.

Claims

1. A micro particle composition comprising nanomagnetic particles distributed within a matrix, wherein the microparticles within the composition have a least one of the following properties:

(a) a VAR of at least about 1 Watts/cm³ under alternating magnetic field conditions suitable for use in a patient;

(b) a density of about 2.7 or less;

or (c) a size range of about 100 nm to about 200 microns.

8. A microparticle composition according to claim 1 wherein the microparticles within the composition have a density of about 2.7 or less.

9. A microparticle composition according to claim 1 wherein the microparticles within the composition have a size of about 100 nm to about 200 microns.

10. A microparticle composition to claim 1 wherein the microparticles within the composition have a VAR of about 10 Watts/cm³ under alternating magnetic field conditions suitable for use in a patient.

11. A micro particle composition according to claim 1 wherein the alternating magnetic field is operated at a frequency in the range of about 50-300 kHz and field strength of about 60-120 Oe.

12. A microparticle composition according to claim 1 wherein the alternating magnetic field is operated at a frequency in the range of about 100-200 kHz and field strength of about 60 Oe.

13. A microparticle composition according to claim 11 wherein the alternating magnetic field is operated at a frequency in the range of about 100 kHz and 20 field strength of about 90 Oe.

14. A microparticle composition according to claim 1 wherein the nanomagnetic particles distributed within the micro particles are superparamagnetic particles.

15. A microparticle composition according to claim 14 wherein the superparamagnetic particles are either:

(a) ferrites of general formula MO.Fe203 where M is a bivalent metal such as Fe, Co, Ni, Mn, Be, Mg, Ca, Ba, Sr, Cu, Zn, Pt or mixtures thereof, or (b) magnetoplumbite type oxides of the general formula MO.6Fe203 where M is a large bivalent ion, metallc iron, cobalt or nickel.

16. A microparticle composition according to claim 15 wherein the superparamagnetic particles are free Fe, Ni, Cr or Co;

oxides of Fe, Ni, Cr or Co;

or mixtures of Fe, Ni, Cr or Co.

17. A microparticle composition according to claim 15 wherein the superparamagnetic particles are prepared from iron oxide such as magnetite (Fe304) or maghemite (y-Fe203) and have a size of less than 50 nm.

18. A microparticle composition according to claim 16 wherein the superparamagnetic particles are maghemite nanoparticles.

19. A microparticle composition according to claim 1 wherein the superparamagnetic particles have a size of between 1 nm and 40 nm.

20. A microparticle composition according to claim 1 wherein the composition is prepared from materials suitable for use in a patient and the particles when delivered to a patient are and placed in an alternating magnetic field are capable of heating tissue in said patient.

21. A microparticle composition according to claim 1 wherein the matrix in which the nanoparticles are distributed is a polymer matrix.

22. A microparticle composition according claim 21 wherein the polymer matrix is suitable for use in human.

23. A micro particle composition according to claim 21 wherein the polymer matrix is a biodegradable polymer matrix.

24. A micro particle composition according to claim 23 wherein the polymer matrix biodegrades to after one to three months following introduction into a patient.

25. A micro particle composition according to claim 1 wherein the micro particles in the composition are adapted for site specific delivery to or accumulation within a tissue in a patient.

26. A microparticle composition according to claim 1 wherein the composition includes pharmaceutically acceptable carriers and or diluents.

27. A micro particle composition according to claim 1 wherein the microparticles in the composition also include bioactive, chemical or radioactive agents that are capable of delivering a therapeutic effect to a patient.

28. A method for heating a target site in a patient including the steps of:

(i) administering a microparticle composition according to claim 22 to a target site in a patient; and

(ii) exposing the target site to an alternating magnetic field, of a clinically acceptable frequency and strength,

wherein the combination of the alternating magnetic field with the micro particle composition induces heat within the target site.

29. The method according to claim 28 wherein the microparticles are of a size and density that permits the transport of the microparticle composition to the capilary beds supplying the target site.

30. The method according to claim 28 wherein the alternating magnetic field is operated at a frequency in the range of about 50-300 kHz and field strength of about 60-120 Oe.

31. The method according to claim 30 wherein the alternating magentic field is operated at a frequency of about 100 kHz and a field strength of about 90 Oe.

32. The use of a micro particle composition according to claim 1 in the manufacture of a medicament for the treatment of diseased tissue.

2. A microparticle composition comprising nanomagnetic particles distributed within a matrix, wherein up to 40% of the volume of each microparticle composition is occupied by the constituent magnetic nanoparticles and the microparticles within the composition have at least one of the following properties:

(a) a VAR of at least about 10 Watts/cm³ under alternating magentic field conditions suitable for use in a patient;

(b) a density of about 2.7 or less;

or (c) a size range of about 100 nm to 200 microns.

3. A microparticle composition according to claim 2 wherein the volume fraction of nanomagnetic particles in the microparticles is less than 30% of the microparticle composition.

4. A microparticle composition according to claim 2 wherein the volume fraction of nanomagnetic particles in the microparticles is less than 20% of the microparticle composition.

5. A microparticle composition according to claim 2 wherein the volume fraction of nanomagnetic particles in the micro particles is less than 15% of the microparticle composition.

6. A microparticle composition according to claim 2 wherein the volume fraction of nanomagnetic particles in the microparticles is less than 10% of the microparticle composition.

7. A microparticle composition according to claim 2 wherein the volume fraction of nanomagnetic particles in the microparticles is less than 5% of the microparticle composition.

33. A micro particle preparation comprising nanomagnetic particles distributed within a matrix, wherein the microparticles within the preparation have at least one of the following properties:

(a) a VAR of at least about 1 Watts/cm³ under alternating magnetic field conditions suitable for use in a patient;

(b) a density of about 2.7 or less;

or (c) a size range of about 100 nm to about 200 microns.

34. The use of a micro particle preparation according to claim 33 in the manufacture of a medicament for the treatment of diseased tissue.