Microneedle Arrays and Methods of Preparing Same

• US 20080262416A1
• Filed: 11/17/2006
• Published: 10/23/2008
• Est. Priority Date: 11/18/2005
• Status: Abandoned Application

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Duan, Daniel C., Johnson, Peter R.
• Application Number:
  US12/089,551
• Publication Number:
  US 20080262416A1
• Time in Patent Office: Days
• US Class Current: 604/46
• CPC Class Codes: A61K 47/26 Carbohydrates, e.g. sugar alcohols, amino sugars, nucleic acids, mono-, di- or oligo-saccharides; Derivatives thereof, e.g. polysorbates, sorbitan fatty acid esters or glycyrrhizin
• CPC Class Codes: A61K 47/32 Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds, e.g. carbomers , poly(meth)acrylates, or polyvinyl pyrrolidone
• CPC Class Codes: A61K 9/0021 Intradermal administration, e.g. through microneedle arrays, needleless injectors mechanical aspects A61M
• CPC Class Codes: A61M 2037/0023 Drug applicators using microneedles
• CPC Class Codes: A61M 2037/0053 Methods for producing microneedles
• CPC Class Codes: A61M 2037/0061 Methods for using microneedles
• CPC Class Codes: A61M 37/0015 by using microneedles
• CPC Class Codes: B81B 2201/055 Microneedles
• CPC Class Codes: B81C 1/0038 Processes for creating layers of materials not provided for in groups B81C1/00357 - B81C1/00373

Abstract

A microneedle array having a substrate and a plurality of microneedles extending out from the substrate with a multi-phase matrix coating on at least a portion of the microneedle surface of the microneedle array. The multi-phase matrix coating comprises an active substance and has a first solid phase and a liquid phase. The first solid phase comprises a water-soluble polymer. Also, a method of providing an active substance- containing matrix coating on a microneedle array in which a water-soluble polymer is applied to the microneedle surface of the array to form a dried coating of water-soluble polymer. A coating solution comprising an active substance, a liquid capable of phase separating from the water-soluble polymer, and a carrier fluid is prepared and applied to the dried coating of water-soluble polymer. At least a portion of the carrier fluid is removed from the array.

Claims

1. A drug delivery device comprising:

a microneedle array comprising a substrate and a plurality of microneedles extending out from the substrate; and

a multi-phase matrix coating containing an active substance on at least a portion of the microneedle surface;

wherein the multi-phase matrix coating comprises a first solid phase and a liquid phase, and

wherein the first solid phase comprises a water-soluble polymer.

2. A drug delivery device as claimed in claim 1 wherein the liquid phase comprises a surfactant.

3. A drug delivery device as claimed in claim 1 wherein the active substance is an antigen.

4. A drug delivery device as claimed in claim 1 wherein the liquid phase is continuous.

5. A drug delivery device as claimed in claim 1 wherein the first solid phase is continuous.

6. A drug delivery device as claimed in claim 1 wherein the water-soluble polymer is selected from the group consisting of polyvinyl alcohol, polyvinyl pyrrolidone, and polyethylene glycol.

7. A drug delivery device as claimed in claim 1 wherein the concentration of water-soluble polymer in the first solid phase is greater than about 50% by weight.

8. A drug delivery device as claimed in claim 1 wherein the multi-phase matrix coating further comprises a second solid phase.

9. A drug delivery device as claimed in claim 8 wherein the second solid phase comprises a sugar.

10. A drug delivery device as claimed in claim 1 wherein the substrate and the plurality of microneedles are made from a water-insoluble polymer.

11. A drug delivery device as claimed in claim 1 wherein the weight ratio of first solid phase to liquid phase is less than about 50:

50.

12. A drug delivery device as claimed in claim 1 wherein the liquid phase has a viscosity of between about 0.1 and 5 Pa·

s.

13. (canceled)

14. A method of preparing a drug delivery device comprising the steps of:

a) providing a microneedle array having a substrate and a plurality of microneedles extending out from the substrate;

b) applying a water-soluble polymer to the microneedle surface to form a dried coating of water-soluble polymer on at least a portion of the microneedles;

c) preparing a coating solution comprising an active substance, a liquid capable of phase separating from the water-soluble polymer, and a carrier fluid;

d) applying the coating solution to the dried coating of water-soluble polymer; and

e) removing at least a portion of the carrier fluid from the array, thereby providing an active substance-containing matrix coating on the microneedle array.

15. A method as claimed in claim 14 and further comprising the step of:

allowing the coating solution to remain in contact with the dried coating of water-soluble polymer for a length of time sufficient to allow at least a portion of the dried coating of water-soluble polymer to be dissolved into the carrier fluid.

16. A method as claimed in claim 14 wherein the carrier fluid is removed from the array by evaporation.

17. A method as claimed in claim 14 wherein the coating solution further comprises a sugar.

18. A method as claimed in claim 14 wherein the active substance-containing matrix coating has multiple phases.

19. A method as claimed in claim 18 wherein the active substance-containing matrix has a first solid phase and a liquid phase.

20. A method as claimed in claim 14 wherein the liquid capable of phase separating from the water-soluble polymer is a surfactant.

21. A method as claimed in claim 14 wherein a surfactant-containing aqueous solution is used to apply the water-soluble polymer to the microneedle surface to form a dried coating of water-soluble polymer.