Drug delivery particle

• US 7,951,402 B2
• Filed: 09/23/2008
• Issued: 05/31/2011
• Est. Priority Date: 08/30/2002
• Status: Active Grant

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Inventors: Lanphere, Janel, Mangin, Stephan, McKenna, Erin, Buiser, Marcia, Naimark, Wendy
• Primary Examiner(s): Peselev; Elli
• Application Number:
  US12/235,978
• Publication Number:
  US 20090035352A1
• Time in Patent Office: 980 Days
• Field of Search: None
• US Class Current: 424/489
• CPC Class Codes: A61B 18/18 by applying electromagnetic radiation, e.g. microwaves radiation therapy A61N5/00
• CPC Class Codes: A61K 49/0452 Solutions, e.g. for injection
• CPC Class Codes: A61K 51/1244 microparticles or nanoparticles, e.g. polymeric nanoparticles
• 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: A61K 9/1635 obtained by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polyvinyl pyrrolidone, poly(meth)acrylates
• CPC Class Codes: A61K 9/1652 Polysaccharides, e.g. alginate, cellulose derivatives; Cyclodextrin homeopathic globules A61K9/1623
• CPC Class Codes: A61L 2300/102 Metals or metal compounds, e.g. salts such as bicarbonates, carbonates, oxides, zeolites, silicates
• CPC Class Codes: A61L 2300/418 Agents promoting blood coagulation, blood-clotting agents, embolising agents
• CPC Class Codes: A61L 2300/606 Coatings
• CPC Class Codes: A61L 24/0015 Medicaments; Biocides
• CPC Class Codes: A61L 24/0036 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 24/0089 containing inorganic fillers not covered by groups A61L24/0078 or A61L24/0084
• CPC Class Codes: A61L 24/02 containing inorganic materials
• CPC Class Codes: A61L 2400/04 Materials for stopping bleeding
• CPC Class Codes: A61L 2430/36 for embolization or occlusion, e.g. vaso-occlusive compositions or devices artificial blood vessels A61L27/507
• CPC Class Codes: A61P 43/00 Drugs for specific purposes, not provided for in groups A61P1/00-A61P41/00

Abstract

A drug delivery particle including a reservoir region having primarily large pores and a metering region. The particle can be highly spherical.

Claims

1. A composition, comprising:

substantially spherical particles having a diameter of from about 10 microns to about 1 cm, the particles including a first region with pores having a first predominant pore size and a second region surrounding the first region and with pores having a second predominant pore size, the first predominant pore size being larger than the second predominant pore size, and the particles comprising cross-linked polyvinyl alcohol,

wherein the second region is about r to 2r/3, and r is a radius of the particles.

2. The composition of claim 1, wherein the first predominant pore size is about 20 micron or more.

3. The composition of claim 1, wherein the first predominant pore size is about 30 micron or more.

4. The composition of claim 1, further comprising a third region from about 2r/3 to r/3 and including pores having a third predominant pore size, wherein the third predominant pore size is larger than the second predominant pore size and smaller than the first predominant pore size.

5. The composition of claim 4, wherein the first region is from about r/3 to C, and C is a center of the particles.

6. The composition of claim 5, wherein the first predominant pore size is about 20 micron or more.

7. The composition of claim 6, wherein the third predominant pore size is from about 2 to about 18 microns.

8. The composition of claim 1, wherein the second region is substantially free of pores greater than about 5 micron.

9. The composition of claim 1, wherein the predominant pore size generally, progressively increases from surface to the center of the particle.

10. The composition of claim 1, wherein the predominant pore size on the particle surface is about 1 micron or less.

11. The composition of claim 1, wherein the second predominant pore size is about 1 micron or less.

12. The composition of claim 11, wherein the second predominant pore size is about 0.1 micron or less.

13. The composition of claim 11, wherein, interior of the second region, the particles have a predominant pore size in the range of about 2 to 35 microns.

14. The composition of claim 12, wherein the first region is from about C to r/3 and the first predominant pore size is about 20 to 35 micron, and C is the center of particles, and r is a radius of the particles.

15. The composition of claim 13, wherein the particles have a third region from r/3 to (2r)/3 and including pores having a third predominant pore size, in which the third predominant pore size is about 2 to 18 micron.

16. The composition of claim 1, wherein the second region is from about (2r)/3 to the surface of the particles, the second predominant pore size is about 10% or less than the first predominant pore size, and r is a radius of the particles.

17. The composition of claim 1, further comprising a carrier fluid having a density of about 1.1 to about 1.4 g/cm³.

18. The composition of claim 1, wherein each of the particles has a sphericity of about 90% or more.

19. The composition of claim 1, wherein the particles have a size uniformity of about +15% or more.

20. The composition of claim 1, wherein the particles include about 1% or less polysaccharide.

21. The composition of claim 20, wherein the polysaccharide is alginate.

22. The composition of claim 21, wherein the alginate has a guluronic acid content of about 60% or greater.

23. The composition of claim 1, wherein the particles are substantially free of collagen.

24. The composition of claim 1, wherein the polyvinyl alcohol is predominantly intrachain 1,3-diols acetalized.

25. The composition of claim 1, further comprising a pharmaceutically acceptable medium in which particles are suspended.