Multi-arm polymeric targeting anti-cancer conjugate

1. A multi-branched drug conjugate having the following structural formula (III) or a pharmaceutically acceptable salt thereof:

wherein R is an organic core, POLY is polyethylene glycol, L is a multivalent linker, T is a targeting molecule, D is an active agent, and q is any integer between 3 and 8, wherein D is a camptothecin-based drug represented by the following formula:

wherein R 1 to R 5 are selected from the following groups independently from each other:

hydrogen, halogen, acyl, alkyl, substituted alkyl, alkoxy, substituted alkoxy, alkenyl, alkynyl, cycloalkyl, hydroxyl, cyano, nitro, azido, amido, hydrazine, amine group, substituted amine group, hydroxycarbonyl, alkoxycarbonyl, alkoxycarbonyloxy, carbamoyloxy, arylsulfonyloxy, and alkylsulfonyloxy; R 6 is H or OR 8 ; R 8 is alkyl, alkenyl, cycloalkyl, halogenated alkyl, or hydroxyalkyl; and R 7 is hydroxyl;

the multivalent linker L is:

symbol “*” represents an attachment point of the multivalent linker L and the targeting molecule T, “#” represents an attachment point of the multivalent linker L and the active agent D, “%” represents an attachment point of the multivalent linker L and POLY, wherein m and m′ are any integer between 1 and 20 respectively, and l and k are any integer between 1 and 10 respectively;

T is an “arginine-glycine-aspartic acid” sequence-containing RGD peptide, tLyp-1, Lyp-1, RPARPAR, Angiopep2, GE11, or folic acid.

2. The multi-branched drug conjugate or a pharmaceutically acceptable salt thereof according to claim 1 , wherein D is irinotecan, SN-38, 10-hydroxycamptothecin, or rubitecan.

3. The multi-branched drug conjugate or a pharmaceutically acceptable salt thereof according to claim 1 , wherein POLY is:

n is 5 to 500.

4. The multi-branched drug conjugate or a pharmaceutically acceptable salt thereof according to claim 1 , wherein the multivalent linker L is:

5. The multi-branched drug conjugate or a pharmaceutically acceptable salt thereof according to claim 1 , wherein T is iRGD or cRGD.

6. The multi-branched drug conjugate or a pharmaceutically acceptable salt thereof according to claim 1 , wherein said multi-branched drug conjugate has a structure represented by structural formula (IV), (V), or (VI):

wherein n is 5 to 500.

7. A multi-branched drug conjugate having the following structure or a pharmaceutically acceptable salt thereof:

8. A drug composition containing the multi-branched drug conjugate or a pharmaceutically acceptable salt thereof according to claim 1 , and a pharmaceutically acceptable excipient.

9. A method for treating colon cancer, lung cancer, breast cancer, ovarian cancer, pancreatic cancer, gastric cancer, brain glioma, and malignant sarcoma, cancer and lymphoma of breast, ovary, colon, kidney, bile duct, lung and brain, comprising administering to a subject in need thereof a therapeutic effective amount of the multi-branched drug conjugate or a pharmaceutically acceptable salt thereof according to claim 1 .

10. A preparation method of a multi-branched drug conjugate or a pharmaceutically acceptable salt thereof, comprising:

wherein R is an organic core, POLY is polyethylene glycol, L is a multivalent linker, T is a targeting molecule, D is an active agent, q is any integer between 3 and 8, and D is a camptothecin-based drug represented by the following formula:

wherein R 1 to R 5 are selected from the following groups independently from each other: hydrogen, halogen, acyl, alkyl, substituted alkyl, alkoxy, substituted alkoxy, alkenyl, alkynyl, cycloalkyl, hydroxyl, cyano, nitro, azido, amido, hydrazine, amine group, substituted amine group, hydroxycarbonyl, alkoxycarbonyl, alkoxycarbonyloxy, carbamoyloxy, aryl sulfonyloxy, and alkylsulfonyloxy; R 6 is H or OR 8 ; R 8 is alkyl, alkenyl, cycloalkyl, halogenated alkyl, or hydroxyalkyl; and R 7 is hydroxyl;

the multivalent linker L is:

symbol “*” represents an attachment point of the multivalent linker L and the targeting molecule T, “#” represents an attachment point of the multivalent linker L and the active agent D, “%” represents an attachment point of the multivalent linker L and POLY, wherein m and m′ are any integer between 1 and 20 respectively, and l and k are any integer between 1 and 10 respectively;

T is an “arginine-glycine-aspartic acid” sequence-containing RGD peptide, tLyp-1, Lyp-1, RPARPAR, Angiopep2, GE11, or folic acid;

(1) the active agent D is attached to the multivalent linker L to obtain a D-L portion;

(2) the D-L portion is attached to a multi-arm polymer R POLY) q to obtain R POLY-L-D) q ; and

(3) R POLY-L-D) q obtained in the previous step is attached to the targeting molecule T.

11. A preparation method of the multi-branched drug conjugate or a pharmaceutically acceptable salt thereof according to claim 10 , wherein D is irinotecan, SN-38, 10-hydroxycamptothecin, or rubitecan;

the multi-arm polymer R POLY) q is 3armPEG20K-SCM, 4armPEG20K-SCM, or 8armPEG20K-SCM;

L is

symbol “*” represents an attachment point of the multivalent linker L and the targeting molecule T, “#” represents an attachment point of the multivalent linker L and the active agent D, and “%” represents an attachment point of the multivalent linker L and POLY; and

T is iRGD, cRGD, tLyp-1, Lyp-1, RPARPAR, Angiopep2, GE11, or folic acid.

12. The multi-branched drug conjugate or a pharmaceutically acceptable salt thereof according to claim 1 , wherein POLY is:

n is 50 to 200.

13. The multi-branched drug conjugate or a pharmaceutically acceptable salt thereof according to claim 1 , wherein POLY is:

n is 113.

14. The multi-branched drug conjugate or a pharmaceutically acceptable salt thereof according to claim 1 , wherein said multi-branched drug conjugate has a structure represented by structural formula (IV), (V), or (VI):

wherein n is 50 to 200.

15. The multi-branched drug conjugate or a pharmaceutically acceptable salt thereof according to claim 1 , wherein said multi-branched drug conjugate has a structure represented by structural formula (IV), (V), or (VI):

wherein n is 113.

16. A drug composition containing the multi-branched drug conjugate or a pharmaceutically acceptable salt thereof according to claim 7 , and a pharmaceutically acceptable excipient.

17. A method for treating colon cancer, lung cancer, breast cancer, ovarian cancer, pancreatic cancer, gastric cancer, brain glioma, and malignant sarcoma, cancer and lymphoma of breast, ovary, colon, kidney, bile duct, lung and brain, comprising administering to a subject in need thereof a therapeutic effective amount of the multi-branched drug conjugate or a pharmaceutically acceptable salt thereof according to claim 7 .