Auristatin drug linker conjugates

1. A compound having the formula:

(D-LU) p -L

or a pharmaceutically acceptable salt or solvate thereof;

wherein L is Ligand Unit, LU is a Linker unit, and D is a Drug unit;

L is a peptide, polypeptide or protein that specifically binds to a target cell population;

LU has the formula -W w -A a ,

W w is a sequence of w independently selected amino acid diradicals, wherein the W proximal to the Drug unit (W 1 ) is a natural (L) amino acid linked via a peptide bond to the Drug unit and the remaining Ws are D-amino acids, provided that W 1 cannot form secondary amide with C-terminal amino acid of D and that the peptide bond can be cleaved by an intracellular protease,

w is an integer ranging from 1 to 12,

A is Stretcher unit, and

a is 1 or 2;

p is an integer of from 1 to 20; and

D has the formula:

wherein the wavy line indicates the peptide bond to LU;

R 1 and R 2 are independently selected from the group consisting of —H and —C 1 -C 8 alkyl, with the proviso that both R 1 and R 2 are not —H;

R 3 is selected from the group consisting of —H, —C 1 -C 8 alkyl, —C 3 -C 8 carbocycle, -aryl, —C 1 -C 8 alkyl-aryl, —X 1 —(C 3 -C 8 carbocycle), —C 3 -C 8 heterocycle and —X 1 —(C 3 -C 8 heterocycle);

R 4 is selected from the group consisting of —H, —C 1 -C 8 alkyl, —C 3 -C 8 carbocycle, -aryl, —X 1 -aryl, —C 1 -C 8 alkyl-(C 3 -C 8 carbocycle), —C 3 -C 8 heterocycle and —X 1 -(C 3 -C 8 heterocycle);

R 5 is selected from the group consisting of —H and methyl;

or R 4 and R 5 jointly form a carbocyclic ring and have the formula —(CR a R b ) n — wherein R a and R b are independently selected from the group consisting of —H and —C 1 -C 8 alkyl and n is selected from the group consisting of 2, 3, 4, 5 and 6;

R 6 is selected from the group consisting of —H and —C 1 -C 8 alkyl;

R 7 is selected from the group consisting of —H, —C 1 -C 8 alkyl, —C 3 -C 8 carbocycle, -aryl, —X 1 -aryl, —X 1 —(C 3 -C 8 carbocycle), —C 3 -C 8 heterocycle and —X 1 —(C 3 -C 8 heterocycle);

each R 8 is independently selected from the group consisting of —H, —OH, —C 1 -C 8 alkyl, —C 3 -C 8 carbocycle and —O—(C 1 -C 8 alkyl);

R 12 is selected from —H, —C 1 -C 8 alkyl, -aryl, —X 1 -aryl, —C 3 -C 8 carbocycle, —X 1 —(C 3 -C 8 heterocycle), —C 1 -C 8 alkylene-NH 2 , —C 3 -C 8 heterocycle and —X 1 -(C 3 -C 8 heterocycle); and

each X 1 is independently —C 1 -C 10 alkylene-.

2. A compound having the formula:

D-LU

or a pharmaceutically acceptable salt or solvate thereof;

wherein LU- is a Linker unit and D is a Drug unit;

LU has the formula W w -A a -,

W W is a sequence of w independently selected amino acid diradicals, wherein the W proximal to the Drug unit (W 1 ) is a natural (L) amino acid linked via a peptide bond to the Drug unit and the remaining Ws are D-amino acids, provided that W 1 cannot form secondary amide with C-terminal amino acid of D and that the peptide bond can be cleaved by an intracellular protease,

w is an integer ranging from 1 to 12,

A is Stretcher unit, and

a is 1 or 2; and

D has the formula:

wherein the wavy line indicates the peptide bond to LU;

R 1 and R 2 are independently selected from the group consisting of —H and —C 1 -C 8 alkyl;

R 3 is selected from the group consisting of —H, —C 1 -C 8 alkyl, —C 3 -C 8 carbocycle, -aryl, —C 1 -C 8 alkyl-aryl, —X 1 - (C 3 -C 8 carbocycle), —C 3 -C 8 heterocycle and —X 1 - (C 3 -C 8 heterocycle);

R 4 is selected from the group consisting of —H, —C 1 -C 8 alkyl, —C 3 -C 8 carbocycle, -aryl, —X 1 -aryl, —C 1 -C 8 alkyl-(C 3 -C 8 carbocycle), —C 3 -C 8 heterocycle and —X 1 - (C 3 -C 8 heterocycle);

R 5 is selected from the group consisting of —H and -methyl;

or R 4 and R 5 jointly form a carbocyclic ring and have the formula —(CR a R b ) n — wherein R a and R b are independently selected from the group consisting of —H and —C 1 -C 8 alkyl and n is selected from the group consisting of 2, 3, 4, 5 and 6;

R 6 is selected from the group consisting of —H and —C 1 -C 8 alkyl;

R 7 is selected from the group consisting of —H, —C 1 -C 8 alkyl, —C 3 -C 8 carbocycle, -aryl, —X 1 -aryl, —X 1 —(C 3 -C 8 carbocycle), —C 3 -C 8 heterocycle and —X 1 —(C 3 -C 8 heterocycle);

each R 8 is independently selected from the group consisting of —H, —OH, —C 1 -C 8 alkyl, —C 3 -C 8 carbocycle and —O—(C 1 -C 8 alkyl);

R 12 is selected from H, —C 1 -C 8 alkyl, -aryl, —X 1 -aryl, —C 3 -C 8 carbocycle, —X 1 —(C 3 -C 8 heterocycle), —C 1 -C 8 alkylene-NH 2 , —C 3 -C 8 heterocycle and —X 1 —(C 3 -C 8 heterocycle); and

each X 1 is independently —C 1 -C 10 alkylene-.

3. The compound of claim 1 or 2 , wherein D has the formula:

wherein R 1 and R 2 are as set forth above.

4. The compound of claim 3 , wherein R 1 and R 2 are —CH 3 .

5. The compound of claim 1 or 2 , wherein w is 2-12 and the remaining W's are D-isomers of a natural amino acid.

6. The compound of claim 1 or 2 , wherein a is 1.

7. The compound of claim 1 or 2 , wherein a is 2.

8. The compound of claim 6 , wherein A has the formula —NH—R 9 -R 11 and R 9 -R 11 have the formula:

wherein R 9 is selected from the group consisting of —C 1 -C 10 alkylene-, —C 3 -C 8 carbocyclo-, -arylene-, —C 1 -C 30 heteroalkylene-, —C 3 -C 8 heterocyclo-, —C 1 -C 10 alkylene-arylene-, -arylene-C 1 -C 10 alkylene-, —C 1 -C 10 alkylene-(C 3 -C 8 carbocyclo)-, —(C 3 -C 8 carbocyclo)-C 1 -C 10 alkylene-, —C 1 -C 10 alkylene-(C 3 -C 8 heterocyclo)-, and —(C 3 -C 8 heterocyclo)-C 1 -C 10 alkylene-.

9. The compound of claim 8 , wherein —NH—R 9 is selected from the group consisting of —NH—C 1 -C 10 alkylene-, —NH—C 1 -C 10 alkylene-NH—C(O)—C 1 -C 10 alkylene-, —NH—C 1 -C 10 alkylene-C(O)—NH—C 1 -C 10 alkylene-, —NH—(CH 2 CH 2 O) r —, —NH—(CH 2 CH 2 O) r —CH 2 —, —NH—C 1 -C 10 alkylene-, —O—C 1 -C 10 alkylene-, —NH—C 1 -C 10 alkylene-NH—C(O)—C 1 -C 10 alkylene-, —NH—(C 3 -C 8 carbocyclo)-, —NH-(arylene-)-, —NH—C 1 -C 10 alkylene-NH—C(O)-(arylene-)-, and —NH—(C 3 -C 8 heterocyclo-)-, wherein r is an integer of from 1-10.

10. The compound of claim 9 , wherein —NH—R 9 is selected from the group consisting of:

11. The compound of claim 9 wherein —NH—R 9 is:

12. The compound of claim 10 , having the formula:

13. The compound of claim 1 or 2 , wherein W 1 is a natural amino acid selected from the group consisting of alanine, arginine, aspartic acid, asparagine, histidine, glycine, glutamic acid, glutamine, phenylalanine, lysine, leucine, serine, tyrosine, threonine, isoleucine, tryptophan and valine.

14. The compound of claim 1 or 2 , wherein the remaining Ws are independently selected from the D-isomers of the group consisting of alanine, arginine, aspartic acid, asparagine, histidine, glycine, glutamic acid, glutamine, phenylalanine, lysine, leucine, serine, tyrosine, threonine, isoleucine, tryptophan and valine.

15. The compound of claim 14 , wherein W 1 is Methionine or Asparagine.

16. The compound of claim 1 or 2 , wherein w is 2.

17. The compound of claim 1 or 2 , wherein W w is selected from the group consisting of -Tyrosine-(D)Aspartic Acid-, -Norvaline-(D)Aspartic Acid-, -Phenylglycine-(D)Lysine-, -Methionine-(D)Lysine- and -Asparagine-(D)Lysine-.

18. The compound of claim 1 or 2 , wherein R 12 is selected from the group consisting of the side chain of phenylalanine, methionine and tryptophan.

19. The compound of claim 1 or 2 , wherein p is 2 to 8.

20. The compound of claim 19 , wherein p is 2 to 5.

21. The compound of claim 1 , wherein L is an antibody.

22. The compound of claim 21 , wherein the antibody (Ab) is attached to each Amino Acid unit (W w ) through a cysteine residue of the antibody and the compound has the following formula:

23. The compound of claim 22 , having the formula:

24. The compound of claim 21 , wherein the antibody is a monoclonal antibody.

25. The compound of claim 21 , wherein the antibody is a bispecific antibody.

26. The compound of claim 21 , wherein the antibody is a humanized antibody.

27. The compound of claim 21 , wherein the antibody is an antibody fragment.

28. The compound of claim 21 , wherein the antibody specifically binds to a B cell antigen.

29. The compound of claim 1 or 2 , or a pharmaceutically acceptable salt or solvate thereof, that is in isolated and purified form.

30. The compound of claim 21 , wherein the antibody specifically binds to CD19, CD20, CD30, CD33, CD70, BCMA, or Lewis Y antigen.

31. A pharmaceutical composition comprising an effective amount of the compound of claim 1 , or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable diluent, carrier or excipient.

32. A method for killing or inhibiting the proliferation of tumor cells or cancer cells comprising treating tumor cells or cancer cells in a patient with an amount of the compound of claim 1 , or a pharmaceutically acceptable salt or solvate thereof, said amount being effective to kill or inhibit the proliferation of the tumor cells or cancer cells.

33. A method for treating cancer comprising administering to a patient in need thereof an amount of the compound of claim 1 , or a pharmaceutically acceptable salt or solvate thereof, said amount being effective to treat cancer.

34. The method of claim 33 , further comprising administering an effective amount of an additional anticancer agent.

35. A method for killing activated lymphocytes associated with an autoimmune disease comprising administering to a patient with an autoimmune disease an amount of the compound of claim 1 , or a pharmaceutically acceptable salt or solvate thereof, the amount being effective to kill activated lymphocytes associated with the autoimmune disease in the patient.

36. A method for treating an infectious viral disease comprising administering to a patient in need thereof an amount of the compound of claim 1 , or a pharmaceutically acceptable salt or solvate thereof, the amount being effective to kill or inhibit the proliferation of virus infected cells in the patient.

37. The method of any one of claims 32 - 36 , wherein the compound is in a formulation comprising a pharmaceutically acceptable diluent, carrier or excipient.

38. The method of any one of claims 32 - 36 , wherein the amount of compound administered to the patient is in the range of about 0.1 to about 10 mg/kg of the patient's weight.

39. The method of claim 38 , wherein the compound is administered at about three week intervals.

40. The method of any one of claims 32 - 36 , wherein the compound is administered intravenously.

41. The method of claim 37 , wherein the compound is formulated in a unit dosage injectable form.

42. The method of any one claims 32 - 36 , wherein the patient is a human.

43. A method of determining inhibition of cellular proliferation by a compound, comprising: exposing mammalian cells in a cell culture medium to the compound of claim 21 , and measuring a cytotoxic activity of the compound, whereby proliferation of the cells is inhibited.

44. The method of claim 43 , further comprising culturing the cells for a period from about 6 hours to about 5 days.

45. A method of inhibiting the growth of tumor cells that overexpress a tumor-associated antigen comprising administering to a patient with said tumer cells the compound of claim 21 which binds specifically to said tumor-associated antigen, and a chemotherapeutic agent wherein the compound and said chemotherapeutic agent are each administered in amounts effective to inhibit growth of tumor cells in the patient.

46. The method of claim 45 , wherein the compound sensitizes the tumor cells to said chemotherapeutic agent.