Brachytherapy Seed with Fast Dissolving Matrix for Optimal Delivery of Radionuclides to Cancer Tissue

Patent metadata

Field	Value
Publication number	US-2016193479-A1
Application number	US-201615069801-A
Country	US
Kind code	A1
Filing date	Mar 14, 2016
Priority date	Sep 2, 2008
Publication date	Jul 7, 2016
Grant date	—

Abstract

A system, method and device for treating tumor cells utilizing a resorbable therapy seed made up of microspheres containing a beta- or alpha-particle-emitting radiation source and a resorbable polymer matrix. These seeds are implanted within the tumor and then rapidly dissolved so as to release the microspheres from the polymer matrix. These microspheres then spread within a preselected target area and provide radiation therapy in a predetermined amount and at a preselected rate according the specific needs and necessities of the users. The configuration of the microspheres, the types of radiation provided and the location and use of these microspheres provides desired localized treatment to target cells while preferentially avoiding or minimizing undesired damage to surrounding tissue. The present invention provides a method for making the seeds, as well as a method for utilizing the seeds as a part of the treatment method.

First claim

1 - 21 . (canceled)

22 . A brachytherapy seed comprising individual particles of sorbitol coated, each individual particle being coated with a biodegradable polymer.

23 . The brachytherapy seed of claim 22 further comprising a radioisotope.

24 . The brachytherapy seed of claim 23 wherein the radioisotope is a beta-particle-emitting radionuclide.

25 . The brachytherapy seed of claim 23 wherein the radioisotope is one of yttrium-90, rhenium-186, rhenium-188, or lutetium-177.

26 . The brachytherapy seed of claim 23 wherein the radioisotope is an alpha-particle-emitting radionuclide.

27 . The brachytherapy seed of claim 23 wherein the radioisotope is one of actinium-225, bismuth-213, bismuth-212, thorium-227, radium-223, astatine-211, or terbium-149.

28 . The brachytherapy seed of claim 22 further comprising at least one marker.

29 . The brachytherapy seed of claim 28 wherein the marker comprises radio opaque material.

30 . The brachytherapy seed of claim 22 further comprising an anti-inflammatory agent.

31 . The brachytherapy seed of claim 22 wherein the polymer comprises one or both of PLA and PLGA.

32 . The brachytherapy seed of claim 22 wherein the polymer has a molecular weight ranging from 5,000 to 100,000.

33 . The brachytherapy seed of claim 22 wherein the polymer comprises both PLA and PLGA, the ratio of PLA to PLGA being from about 3:1 to about 1:1.

34 . The brachytherapy seed of claim 22 wherein the polymer is provided to constitute from 0.5 to 5 percent of the seed.

35 . A method for preparing a brachytherapy seed, the method comprising:
providing a structure comprising a radioisotope; providing a mixture of particles, individual ones of the particles comprising sorbitol, each individual particle being coated with a biodegradable polymer; and pressing the mixture of particles about the structure to form a brachytherapy seed comprising the particles.

36 . The method of claim 35 wherein the providing the mixture of particles comprises binding the sorbitol with the polymer to form the particles.

37 . The method of claim 35 wherein the polymer comprises one or both of PLA and PLGA.

38 . The method of claim 35 wherein the polymer has a molecular weight ranging from 5,000 to 100,000.

39 . The method of claim 35 wherein the polymer comprises both PLA and PLGA, the ratio of PLA to PLGA being from about 3:1 to about 1:1.

40 . The method of claim 35 wherein the polymer is provided to constitute from 0.5 to 5 percent of the seed.

41 . The method of claim 35 wherein the providing the mixture of particles comprises binding the sorbitol with the polymer to form the particles.

42 . The method of claim 41 wherein the polymer is natural.

Assignees

• Battelle Memorial Institute
• Univ Utah Res Found

Inventors

• Fisher Darrell R
• Bae You Han
• Gao Zhonggao

Classifications

• A61K51/0491

  Sugars, nucleosides, nucleotides, oligonucleotides, nucleic acids, e.g. DNA, RNA, nucleic acid aptamers · CPC title

• B29C43/027

  having an axis of symmetry (B29C43/102 takes precedence) · CPC title

• B29K2067/046

  PLA, i.e. polylactic acid or polylactide · CPC title

• B29C43/003

  characterised by the choice of material · CPC title

• A61N5/1001 Primary

  using radiation sources introduced into or applied onto the body; brachytherapy · CPC title