Targeted agents useful for diagnostic and therapeutic applications

• US 6,409,987 B1
• Filed: 04/06/2000
• Issued: 06/25/2002
• Est. Priority Date: 04/07/1999
• Status: Expired due to Term

• Current Assignee: Smithfield BioScience, Inc. (Celsus, Inc.)
• Original Assignee: Intimax Corporation
• Inventors: Cardin, Alan D., Van Gorp, Cornelius L.
• Primary Examiner(s): JONES, DAMERON LEVEST
• Application Number:
  US09/544,266
• Time in Patent Office: 810 Days
• Field of Search: 424/1.11, 424/1.65, 424/1.69, 424/1.73, 424/9.1, 424/9.3, 424/9.4, 424/9.5, 424/9.6, 424/9.7, 424/9.8, 534/7, 534/10-16, 530/350
• US Class Current: 424/1.73
• CPC Class Codes: A61K 51/065 conjugates with carriers being macromolecules

Abstract

A selectively targeted agent comprising a dermatan sulfate having more than about 25% repeating L-iduronic acid→4,6-di-O-sulfated N-acetyl-D-galactosamine disaccharide units that is covalently attached or bonded to a radioactive metal-ion binding moiety. The targeted agent is useful in preparing radiagnostic and/or radiopharmaceutical agents for diagnostic and/or therapeutic treatment when combined with an appropriate radioactive metal ion such as ^99mTc, ¹⁸⁶Re or ¹⁸⁸Re.

Claims

1. A targeted agent having an avidity for thrombin that comprises a dermatan sulfate having more than about 25% repeating L-iduronic acid→

4,6-di-O-sulfated N-acetyl-D-galactosamine disaccharide units that is covalently attached to a radioactive metal-ion binding moiety.

2. The agent of claim 1 wherein the dermatan sulfate has more than about 50% repeating L-iduronic acid→

4,6-di-O-sulfated N-acetyl-D-galactosamine disaccharide units.

3. The agent of claim 2 wherein the dermatan sulfate has a molecular weight of from about 1,000 Daltons to about 60,000 Daltons.

4. The agent of claim 3 wherein the dermatan sulfate has more than about 75% repeating L-iduronic acid→

4,6-di-O-sulfated N-acetyl-D-galactosamine disaccharide units.

5. The agent of claim 4 wherein the dermatan sulfate has a molecular weight of from about 2,500 to about 37,500 Daltons.

6. The agent of claim 4 wherein the iduronic acid moiety of the dermatan sulfate has been derivatized to provide a free aldehyde group capable of being covalently bonded to the radioactive metal-ion binding moiety.

7. The agent of claim 4 wherein the radioactive metal-ion binding moiety has the formula (I):

8. The agent of claim 4 wherein the radioactive metal-ion binding moiety has the formula (II):

9. The agent of claim 4 wherein the radioactive metal-ion binding moiety has formulas (III or IV):

or,

10. The agent of claim 4 wherein the radioactive metal-ion binding moiety has formulas (V or VI):

wherein each R⁵ can be independently H, CH₃ or C₂H₅;

each (pgp)⁵ is independently a thiol protecting group or H;

m, n, and p are independently 2 or 3;

A is a linear or cyclic lower alkyl, aryl, or heterocyclyl, combinations of linear or cyclic lower alkyl, aryl, or heterocyclyl, or substituted linear or cyclic lower alkyl, aryl, or heterocyclyl; and

X is (linker)-dermatan sulfate;

or

wherein each R⁵ is independently H, lower alkyl having 1 to 6 carbon atoms, phenyl, or phenyl substituted with lower alkyl or lower alkoxy;

m, n and p are independently 1 or 2;

A is linear or cyclic lower alkyl, aryl, heterocyclyl, combinations or substituted derivatives thereof;

V is H or —

CO-(linker)-dermatan sulfate;

R⁶ is H or a (linker)-dermatan sulfate;

provided that when V is H, R⁶ is a (linker)-dermatan sulfate and when R⁶ is H, V is a —

CO-(linker)-dermatan sulfate.

11. The agent of claim 4 wherein the radioactive metal-ion binding moiety has the formula (VII):

wherein R₁, R₂, R₅ and R₆ are independently selected from H;

carboxyl;

lower alkyl; and

lower alkyl substituted with a group selected from hydroxyl, sulfhydryl, halogen, carboxyl and aminocarbonyl;

or a conjugating group;

R₃ and R₄ are independently selected from H or a sulfur protecting group;

X is selected from O, the group NH₂⁺, or the group CH₂ each of which may have attached thereto a conjugating group;

Y and Z are independently selected from the group CR₁R₂ or NR₇; and

R₇ is selected from H, carboxyl, lower alkyl and lower alkyl substituted with hydroxyl, carboxyl and halogen.

12. The agent of claim 4 wherein the radioactive metal-ion binding moiety has the formula (VIII):

wherein X is a linear or branched, saturated or unsaturated C_1-4 alkyl chain that is optionally interrupted by one or two heteroatoms selected from N, O and S; and

is optionally substituted by one or more substituents selected from halogen, hydroxyl, amino, carboxyl, C_1-4 alkyl, aryl and C(O)Z;

Y is H or a substituent defined by X;

X and Y may together form a 5- to 8-membered saturated or unsaturated heterocyclic ring optionally substituted by one or more substituents selected from halogen, hydroxyl, amino, carboxyl, oxo, C_1-4 alkyl, aryl and C(O)Z;

R₁ through R₄ are selected independently from H;

carboxyl;

C_1-4 alkyl;

C_1-4 alkyl substituted with a substituent selected from hydroxyl, amino, sulfhydryl, halogen, carboxyl, C_1-4 alkoxycarbonyl and aminocarbonyl;

an alpha carbon side chain of a D- or L-amino acid other than proline; and

C(O)Z;

R₅ and R₆ are selected independently from H;

carboxyl;

amino;

C_1-4 alkyl;

C_1-4 alkyl substituted by a substituent selected from hydroxyl, carboxyl and amino; and

C(O)Z;

R₇ is selected from H and a sulfur protecting group; and

Z is selected from hydroxyl, alkoxy, an amino acid residue, and a linking group.

13. The agent of claim 4 wherein the radioactive metal-ion binding moiety has the formula (IX):

14. A kit for preparing a diagnostic and/or therapeutic agent, which comprises predetermined quantity of the agent of claim 4 and a sufficient amount of a the radioactive metal ion.

15. The kit of claim 14 wherein the radioactive metal ion is selected from the group consisting of ^99mTc, ¹¹¹In, ⁶⁷Ga, ¹⁶⁹Yb, ²⁰¹Tl, ¹⁵³Sm, ²⁰¹Tl, ¹⁸⁶Re and ¹⁸⁸Re.

16. The kit of claim 15 wherein the radioactive metal ion is ^99mTc.

17. The kit of claim 15 the radioactive metal ion is selected from the group consisting of ¹⁸⁶Re and ¹⁸⁸Re.

18. A method for radiodiagnostic imaging a disease state associated with surface-bound thrombin activation, which comprises the steps of combining a predetermined quantity of the agent of claim 4 and a sufficient amount of ^99mTc to form a radiodiagnostic imaging agent, and then administering a diagnostic amount of the radiodiagnostic imaging agent to a person to be diagnosed.

19. A method for radiopharmaceutical treatment of a disease state associated with surface-bound thrombin activation, which comprises the steps of combining a predetermined quantity of the agent of claim 4 and a sufficient amount of a radioactive metal ion selected from the group consisting of ¹⁸⁶Re and ¹⁸⁸Re to form a radiopharmaceutical agent, and then administering a therapeutic amount of the radiopharmaceutical agent to a person to be treated.

20. The agent of claim 4 in combination or administered with heparin cofactor II.