Polymer drug conjugates with tether groups for controlled drug delivery

1. A linear, cyclodextrin containing polymer conjugate, comprising a therapeutic agent covalently attached to a polymer through a tether, wherein the tether comprises an aminoalkylcarbonyloxyalkyl moiety whereupon being subjected to biological conditions the tether undergoes self-cyclization to form a five- or six-membered heterocyclic ring that comprises at least one heteroatom selected from nitrogen, oxygen and sulfur, thereby releasing the therapeutic agent.

2. The polymer conjugate of claim 1 , wherein the cyclization forms a five-membered heterocyclic ring.

3. The polymer conjugate of claim 2 , wherein the five-membered heterocyclic ring comprises two oxygen atoms.

4. The polymer conjugate of claim 1 , wherein the cyclodextrin containing polymer comprises a copolymer comprising cyclodextrin moieties and linker groups that do not comprise cyclodextrin moieties.

5. The polymer conjugate of claim 4 , wherein the cyclodextrin moieties and the linker groups alternate in the copolymer.

6. The polymer conjugate of claim 4 , wherein each linker group independently comprises an alkyl chain, a polyethylene glycol (PEG) chain, polysuccinic anhydride, poly-L-glutamic acid, poly(ethyleneimine), an oligosaccharide, or an amino acid chain.

7. The polymer conjugate of claim 4 , wherein each linker group comprises PEG.

8. The polymer conjugate of claim 1 , wherein the cyclodextrin is alpha-, beta-, or gamma-cyclodextrin.

9. The polymer conjugate of claim 1 , wherein the therapeutic agent is a small molecule, a peptide, a protein, a nucleotide, a polynucleotide, or a polymer that has therapeutic function.

10. The polymer conjugate of claim 1 , wherein the therapeutic agent is an anti-cancer, anti-fungal, anti-bacterial, anti-mycotic, or anti-viral therapeutic.

11. The polymer conjugate of claim 1 , wherein the therapeutic agent is a protease inhibitor.

12. The polymer conjugate of claim 1 , wherein the therapeutic agent comprises an amino, hydroxyl, or thiol group.

13. The polymer conjugate of claim 12 , wherein the therapeutic agent is attached to the tether through the amino, hydroxyl, or thiol group of the therapeutic agent.

14. The polymer conjugate of claim 1 , wherein the therapeutic agent is attached to the tether through the amino group of the therapeutic agent.

15. The polymer conjugate of claim 1 , wherein the tether comprises an amino acid or peptide, or derivative thereof.

16. The polymer conjugate of claim 1 , wherein the therapeutic agent makes up at least 5% by weight of the polymer conjugate.

17. The polymer conjugate of claim 1 , wherein the therapeutic agent makes up at least 10% by weight of the polymer conjugate.

18. The polymer conjugate of claim 1 , wherein the therapeutic agent makes up at least 15% by weight of the polymer conjugate.

19. The polymer conjugate of claim 1 , wherein the polymer conjugate has a molecular weight of 10,000-500,000 amu.

20. A pharmaceutical composition comprising a polymer conjugate of claim 1 , and a pharmaceutically acceptable excipient, or a pharmaceutically acceptable salt thereof.

21. The pharmaceutical composition of claim 20 , wherein upon administration to a subject, the therapeutic agent is delivered to the subject for a period of from about 1 to about 2,000 hours.

22. The polymer conjugate of claim 1 , wherein the polymer comprises a copolymer comprising beta-cyclodextrin moieties and PEG groups that alternate in the copolymer, the therapeutic agent is an anti-cancer agent.

23. A pharmaceutical composition comprising the polymer conjugate of claim 22 , and a pharmaceutically acceptable excipient, or a pharmaceutically acceptable salt thereof.