Prodrugs comprising an insulin linker conjugate

1. A prodrug comprising:

a hydrogel (Z) with backbone moieties of formula C-(A-Hyp) 4 , wherein:

each A is independently selected from the formula —(CH 2 ) n1 (OCH 2 CH 2 ) n X′—,

wherein:

n1 is 1 or 2;

n is an integer ranging from 5 to 50; and

X′ is an amide linkage linking A and Hyp;

each Hyp is independently selected from hyperbranched polypeptides comprising lysine;

the backbone moieties are crosslinked by poly(ethylene glycol)-based crosslinker moieties, comprising m ethylene glycol units, wherein m is an integer ranging from 3-100, and terminated by at least two hydrolytically degradable bonds;

a linker L 2 connected to a backbone moiety, wherein:

L 2 is a single chemical bond or is a C 1-20 alkyl chain, which is optionally interrupted by one or more groups independently selected from —O— and C(O)N(R 3aa ) and is optionally substituted with one or more groups independently selected from OH and C(O)N(R 3aa R 3aaa ), wherein R 3aa and R 3aaa are independently selected from the group consisting of H and C 1-4 alkyl; and

L 2 is attached to Z via a terminal group selected from the group consisting of

wherein L 2 is attached to the sulfur atom in structure X and Z is attached to the nitrogen atom in structure X or L 2 is attached to the nitrogen atom in structure XI and Z is attached to the sulfur atom in structure XI; and

an insulin-linker conjugate D-L 1 , wherein:

D is insulin; and

L 1 is:

wherein:

the dashed line indicates the point of attachment of L 1 to one of the amino groups of insulin through an amide bond;

X is C(R 3 R 3a );

R 1a and R 3a are independently selected from the group consisting of H, NH(R 2b ), N(R 2b )C(O)R 4 and C 1-4 alkyl and optionally substituted with L 2 -Z;

R 1 , R 2 , R 2a , R 2b , R 3 , and R 4 are independently selected from the group consisting of H and C 1-4 alkyl, and optionally substituted with L 2 -Z; and

L 1 is substituted with one L 2 -Z provided that the hydrogen marked with the asterisk in formula (I) is not replaced;

or a pharmaceutically acceptable salt thereof, wherein said prodrug is in the form of microparticles.

2. The prodrug of claim 1 , wherein in formula (I) R 2 is replaced by L 2 -Z.

3. The prodrug of claim 1 , wherein in formula (I) R 1 is replaced by L 2 -Z.

4. The prodrug of claim 1 , wherein R 3a is N(R 2b )C(O)R 4 .

5. The prodrug of claim 1 , wherein R 3a is L 2 -Z.

6. The prodrug of claim 1 , wherein R 3a is N(R 2b )-L 2 -Z.

7. The prodrug of claim 1 , wherein the insulin is attached to L 1 through the nitrogen N αA1 .

8. The prodrug of claim 1 , wherein the insulin is recombinant human insulin.

9. The prodrug of claim 8 , wherein the recombinant human insulin is attached to L 1 through the nitrogen of a lysine side chain of the insulin.

10. The prodrug of claim 1 , wherein the crosslinker moieties have a molecular weight in the range of from 0.5 kDa to 5 kDa.

11. The prodrug of claim 1 , wherein L 2 is attached to Z via a terminal group having the structure:

wherein the dashed lines indicate the attachment to L 2 and Z, respectively.

12. The prodrug of claim 1 , of formula (IIa):

wherein N ε -Insulin refers to insulin connected via one lysine side chain.

13. The prodrug of claim 1 , wherein the backbone moieties comprise a branching core of the following formula:

wherein the dashed line indicates attachment to the remainder of the backbone moiety.

14. The prodrug of claim 1 , wherein the backbone moieties comprise a structure of the following formula:

C—[(CH 2 ) n1 (OCH 2 CH 2 ) n —N] 4 —

wherein n is an integer ranging from 5 to 50, n1 is 1, and the dashed line indicates attachment to the rest of the molecule.

15. The prodrug of claim 1 , wherein the backbone moieties comprises a hyperbranched moiety Hyp of the following formula:

wherein the dashed lines indicate attachment to the rest of the molecule and carbon atoms marked with asterisks indicate S-configuration.

16. The prodrug of claim 1 , wherein the backbone moieties are attached to at least one spacer of the following formula:

wherein one of the dashed lines indicates attachment to the hyperbranched moiety Hyp and the second dashed line indicates attachment to the rest of the molecule; and

wherein m′ is an integer ranging from 2 to 4.

17. The prodrug of claim 1 , wherein the backbone moieties are attached to at least one spacer of the following formula:

wherein the dashed line marked with the asterisk indicates the bond between the hydrogel and the nitrogen of the thiosuccinimide group of structure X,

wherein the other dashed line indicates attachment to Hyp, and

wherein p is an integer ranging from 0 to 10.

18. The prodrug of claim 16 , wherein the poly(ethylene glycol)-based crosslinker moieties are symmetrically connected through ester bonds to two alpha, omega-aliphatic dicarboxylic acid spacers.

19. The prodrug of claim 1 , wherein the microparticles have a diameter ranging from 1 to 500 μm.

20. An insulin-linker conjugate of formula (IIIa)

wherein N ε -Insulin refers to insulin connected via one lysine side chain.

21. A pharmaceutical composition comprising a prodrug of claim 1 or a pharmaceutically acceptable salt thereof together with a pharmaceutically acceptable excipient.

22. A dry pharmaceutical composition according to claim 21 .

23. A lyophilized pharmaceutical composition according to claim 22 .

24. A single dose pharmaceutical composition according to any one of claims 21 to 23 .

25. The pharmaceutical composition of claim 21 , comprising one or more additional biologically active agents.

26. A suspension comprising the pharmaceutical composition according to claim 21 or 25 .

27. A method of treating a disease or disorder chosen from the group consisting of hyperglycemia, pre-diabetes, impaired glucose tolerance, diabetes type I, and diabetes type II, comprising administering to a patient in need thereof a prodrug according to claim 1 , thereby treating the disease or disorder.