PSMA binding ligand-linker conjugates and methods for using
Described herein are prostate specific membrane antigen (PSMA) binding conjugates that are useful for delivering therapeutic, diagnostic and imaging agents. Also described herein are pharmaceutical composition containing them and methods of using the conjugates and compositions. Also described are processes for manufacture of the conjugates and the compositions containing them.
1. A conjugate comprising a ligand of PSMA (B), a linker (L), and a drug (D), wherein the linker is covalently bound to the drug and the linker is covalently bound to the ligand, wherein
B is a ligand of prostate specific membrane antigen (PSMA) that is a urea of two amino acids, wherein the two amino acids are independently selected from asparagine, aspartic acid, cysteine, glutamic acid, lysine, glutamine, arginine, serine, ornithine, threonine and combinations thereof;
L is a divalent linker of 14 to 24 atoms in length, the divalent linker comprising a divalent tripeptide comprising one or more optionally substituted Phe and one or more optionally substituted Tyr; and
D is a radioactive isotope of a metal coordinated to a chelating group.
2. The conjugate of claim 1 , wherein B is of the formula
wherein R 1 is hydrogen and R 2 is a substituted carboxylic acid, wherein the substituted carboxylic acid is covalently bound to the linker.
3. The conjugate of claim 1 , wherein the tripeptide comprises an optionally substituted phenylalanine and a substituted tyrosine.
4. The conjugate of claim 2 , wherein the tripeptide comprises an optionally substituted phenylalanine and a substituted tyrosine.
5. The conjugate of claim 1 , wherein the chelating group is not DOTA.
6. A pharmaceutical composition comprising a conjugate of claim 1 and at least one pharmaceutically acceptable carrier, excipient, or a combination thereof.