Polymer conjugates of biologically active agents and extension moieties for facilitating conjugation of biologically active agents to polymeric terminal groups

• US 6,756,037 B2
• Filed: 03/29/2001
• Issued: 06/29/2004
• Est. Priority Date: 03/31/2000
• Status: Expired due to Fees

• Current Assignee: Enzon Pharmaceuticals Inc. (Icahn Associates Holding LLC)
• Original Assignee: Enzon Pharmaceuticals Inc. (Icahn Associates Holding LLC)
• Inventors: Choe, Yun H., Greenwald, Richard B.
• Primary Examiner(s): Riley, Jezia
• Application Number:
  US09/823,283
• Publication Number:
  US 20010051144A1
• Time in Patent Office: 1,188 Days
• Field of Search: 424/178.1, 424/179.1, 424/194.1, 424/181.1, 424/450, 424/180.1
• US Class Current: 424/178.1
• CPC Class Codes: A61K 47/60 the organic macromolecular compound being a polyoxyalkylene oligomer, polymer or dendrimer, e.g. PEG, PPG, PEO or polyglycerol

Abstract

The present invention is directed to polymer conjugates of biologically active agents and methods of preparing the same. In preferred aspects of the invention, the conjugates are of the formula

wherein G is a linear or branched polymer residue such as a polyethylene glycol and B is a residue of an amine-containing or a hydroxyl-containing biologically active moiety such as Ara-C.

Claims

1. A compound comprising the formula:

wherein;

G is a linear or branched polymer residue;

Y₁ and Y₂ are independently O, S, or NR₉;

M₁-M₃ are independently O, S, or NR₁₀;

M₄ is X or Q;

wherein X is an electron withdrawing group and Q is a moiety containing a free electron pair positioned three to six atoms from C(═

Y₂);

B is a residue of an amine-containing moiety or a residue of a hydroxyl-containing moiety;

R_1-10 are independently selected from the group consisting of hydrogen, C_1-6 alkyls, C_3-12 branched alkyls, C_3-8 cycloalkyls, C_1-4 substituted alkyls, C_3-8 substituted cycloalkyls, aryls, substituted aryls, aralkyls, C_1-4 heteroalkyls and substituted C_1-4 heteroalkyls;

a, b, c, d, h, i and n ore each independently zero or a positive integer; and

e, f and g are each independently a positive integer.

2. The compound of claim 1, wherein G includes a capping group A, selected from the group consisting of hydrogen, CO₂H, C_1-6 alkyl moieties, and

3. A compound of claim 2, of the formula:

4. The compound of claim 1, wherein a, b, c, d, h, i and n are independently zero, one or two.

5. The compound of claim 1, wherein Y₁ and Y₂ are both O.

6. The compound of claim 1, wherein M₂ is NH and d is one.

7. The compound of claim 1, wherein R₇ and R₈ are both H.

8. The compound of claim 1, wherein n is 1.

9. The compound of claim 1, wherein a is 0.

10. The compound of claim 1, wherein a is 1.

11. The compound of claim 1, wherein c is 0.

12. The compound of claim 1, wherein g is 2, M₃ is O, e is 2, f is 1 and R₃ and R₄ are H.

13. The compound of claim 12, wherein b, d, h and n are 1, R₅ and R₆ are H and M₂ is NH.

14. The compound of claim 12, wherein b, d and n are 1, M₂ is NH and R₃ and R₄ are H.

15. The compound of claim 1, wherein B is a residue of an amine-containing moiety.

16. The compound of claim 15, wherein said amine-containing moiety is

wherein

R_12-13 are independently selected from the group consisting of hydrogen, C_1-6 alkyls, C_3-12 branched alkyls, C_3-8 cycloalkyls, C_1-6 substituted alkyls, C_3-8 substituted cycloalkyls, aryls, halo, substituted aryls, aralkyls, C_1-6 heteroalkyls, substituted C_1-6 heteroalkyls;

R_14-18 are independently selected from alkoxy, e.g. OR₁₉ or, in the alternative, H, OH, N₃, NHR₂₀, NO₂ or CN, fluoro, chloro, bromo, iodo, where R_19-20 are independently selected from the same group which defines R_12-13.

17. The compound of claim 1, wherein G is O—

(CH₂CH₂O)_x or O—

(CH(CH₃)CH₂O)_x, wherein x is the degree of polymerization.

18. The compound of claim 17, wherein G is O—

(CH₂CH₂O)_x and x is a positive integer selected so that the weight average molecular weight is at least about 20,000.

19. The compound of claim 18, wherein G has a weight average molecular weight of from about 20,000 to about 100,000.

20. The compound of claim 19, wherein G has a weight average molecular weight of from about 25,000 to about 60,000.

21. A compound of claim 1, selected from the group consisting of:

22. A compound of claim 3, selected from the group consisting of:

23. A compound of claim 1, selected from the group consisting of:

24. A compound of claim 3, selected from the group consisting of:

27. A method of treatment, comprising:

administering to a mammal in need of such treatment an effective amount of a compound of claim 1, wherein B is a residue of a biologically active moiety.

28. A method of treatment, comprising:

administering to a mammal in need of such treatment an effective amount of a compound of claim 3, wherein B is a residue of a biologically active moiety.

30. A compound of claim 1, selected from the group consisting of:

31. A compound of claim 3, selected from the group consisting of:

32. The compound of claim 1, wherein e, f and g are each independently one or two.

25. A method of preparing a polymeric conjugate, comprising:

a) reacting a biologically active moiety having an unprotected amine or hydroxyl group with a compound of the formula

wherein

B₁ is a leaving group capable of reacting with an unprotected amine or hydroxyl group;

B₂ is a cleavable protecting group;

Y₂ is O, S, or NR₉;

M₂-M₃ are independently O, S, or NR₁₀;

M₄ is X or Q;

wherein X is an electron withdrawing group and Q is a moiety containing a free electron pair positioned three to six atoms from C(═

Y₃);

R_3-6, R₉ and R₁₀ are independently selected from the group consisting of hydrogen, C_1-6 alkyls, C_3-12 branched alkyls, C_3-8 cycloalkyls, C_1-6 substituted alkyls, C_3-8 substituted cycloalkyls, aryls, substituted aryls, aralkyls, C_1-6 heteroalkyls and substituted C_1-6 heteroalkyls;

d, h, and i are each independently zero or a positive integer; and

e, f and g are each independently a positive integer

to form a protected intermediate of the formula;

wherein

B is a residue of an amine-containing moiety a residue of a hydroxyl-containing moiety;

b) deprotecting the resultant intermediate by removing B₂; and

c) reacting the deprotected intermediate with a compound of the formula

wherein

B₃ is a leaving group;

G is a polymer residue;

Y₁ is O, S, or NR₉;

M₁ is O, S, or NR₁₀;

R₁, R₂, R₇, R₉ and R₁₀ are independently selected from the group consisting of hydrogen, C_1-6 alkyls, C_3-12 branched alkyls, C_3-8 cycloalkyls, C_1-6 substituted alkyls, C_3-8 substituted cycloalkyls, aryls, substituted aryls, aralkyls, C_1-6 heteroalkyls and substituted C_1-6 heteroalkyls; and

a, b and c are each independently zero or a positive integer, whereby a polymeric conjugate is formed.

26. A method of preparing a polymeric conjugate, comprising:

reacting a polymer-spacer intermediate of the formula

wherein

B₁ is a leaving group capable of reacting with an unprotected amine or hydroxyl group;

G is a polymer residue;

Y₁ and Y₂ are independently O, S, or NR₉;

M₁-M₃ are independently O, S, or NR₁₀;

M₄ is X or Q;

wherein X is an electron withdrawing group and Q is a moiety containing a free electron pair positioned three to six atoms from C(═

Y₂);

B is a residue of an amine-containing moiety or a residue of a hydroxyl-containing moiety;

R_1-10 are independently selected from the group consisting of hydrogen, C_1-6 alkyls, C_3-12 branched alkyls, C_3-8 cycloalkyls, C_1-6 substituted alkyls, C_3-8 substituted cycloalkyls, aryls, substituted aryls, aralkyls, C_1-6 heteroalkyls and substituted C_1-6 heteroalkyls;

a, b, c, d, h, i and n are each independently zero or a positive integer; and

e, f and g are each independently a positive integer;

and thereafter reacting intermediate with a biologically active moiety having an unprotected amine or hydroxyl group to form the polymeric conjugate.

29. A compound of the formula:

wherein

B is a residue of an amine-containing moiety or a residue of a hydroxyl-containing moiety;

B₂ is a cleavable protecting group;

Y₂ is O, S, or NR₉;

M₂-M₄ are independently O, S, or NR₁₀,

M₄ is X or Q;

wherein X is an electron withdrawing group and Q is a moiety containing a free electron pair positioned three to six atoms from C(═

Y₂);

R_{3-6, 9 and 10} are independently selected from the group consisting of hydrogen, C_1-6 alkyls, C_3-12 branched alkyls, C_3-8 cycloalkyls, C_1-6 substituted alkyls, C_3-8 substituted cycloalkyls, aryls, substituted aryls, aralkyls, C_1-6 heteroalkyls and substituted C_1-6 heteroalkyls;

d, e, f, g, h, and i are each independently zero or a positive integer.