Bicyclic peptide ligands specific for MT1-MMP
The present invention relates to polypeptides which are covalently bound to molecular scaffolds such that two or more peptide loops are subtended between attachment points to the scaffold. In particular, the invention describes peptides which are high affinity binders of membrane type 1 metalloprotease (MT1-MMP). The invention also describes drug conjugates comprising said peptides, conjugated to one or more effector and/or functional groups which have utility in imaging and targeted cancer therapy.
1. A peptide ligand specific for MT1-MMP (membrane type 1 metalloprotease), or a pharmaceutically acceptable salt thereof, comprising a polypeptide comprising at least three cysteine residues, separated by at least two loop sequences, and a molecular scaffold which forms covalent bonds with the cysteine residues of the polypeptide such that at least two polypeptide loops are formed on the molecular scaffold, wherein the peptide ligand comprises the amino acid sequence:
(I)
(SEQ ID NO: 1)
-C i -X 1 -U/O 2 -X 3 -X 4 -G 5 -C ii -E 6 -D 7 -F 8 -Y 9 -X 10 -X 11 -C iii -
wherein:
C i , C ii and C iii represent first, second and third cysteine residues, respectively;
each of X 1 , X 3 , X 4 , X 10 and X 11 represents any natural amino acid residue;
U/O 2 represents that position 2 of the loop sequence between C i and C ii is U or O;
U represents a polar, uncharged amino acid residue selected from the group consisting of N, C, Q, M, S and T; and
O represents a non-polar aliphatic amino acid residue selected from the group consisting of G, A, I, L, P and V.
2. The peptide ligand according to claim 1 , or a pharmaceutically acceptable salt thereof, wherein X 1 is selected from the group consisting of Y, M, F and V.
3. The peptide ligand according to claim 1 , or a pharmaceutically acceptable salt thereof, wherein U/O 2 represents N or G.
4. The peptide ligand according to claim 1 , or a pharmaceutically acceptable salt thereof, wherein X 3 is U or Z, wherein U is selected from the group consisting of N, C, Q, M, S and T, and Z is selected from the group consisting of D and E; or
wherein U is Q and Z is E.
5. The peptide ligand according to claim 1 , or a pharmaceutically acceptable salt thereof, wherein X 4 is selected from the group consisting of F, W and Y.
6. The peptide ligand according to claim 1 , or a pharmaceutically acceptable salt thereof, wherein
X 10 is selected from the group consisting of D and E; and
X 11 is selected from the group consisting of G, A, I, L, P and V.
7. The peptide ligand according to claim 1 , or a pharmaceutically acceptable salt thereof, wherein the amino acid sequence SEQ ID NO: 1 is selected from the group consisting of:
(SEQ ID NO: 6)
-C i -Y/M/F/V-U/O-U/Z-J-G-C ii -E-D-F-Y-Z-O-C iii -,
(SEQ ID NO: 7)
-C i -Y/M/F/V-N/G-E/Q-F-G-C ii -E-D-F-Y-D-I-C iii -,
(SEQ ID NO: 8)
-C i -Y/M/F-N/G-E/Q-F-G-C ii -E-D-F-Y-D-I-C iii -,
(SEQ ID NO: 9)
-C i -Y/M-N-E/Q-F-G-C ii -E-D-F-Y-D-I-C iii -, and
(SEQ ID NO: 2)
-C i -Y-N-E-F-G-C ii -E-D-F-Y-D-I-C iii -.
8. The peptide ligand according to claim 1 , or a pharmaceutically acceptable salt thereof, wherein the amino acid sequence SEQ ID NO: 1 is selected from the group consisting of:
(SEQ ID NO: 2)
-C i -Y-N-E-F-G-C ii -E-D-F-Y-D-I-C iii -;
(SEQ ID NO: 10)
-C i -M-N-Q-F-G-C ii -E-D-F-Y-D-I-C iii -;
(SEQ ID NO: 11)
-C i -F-G-E-F-G-C ii -E-D-F-Y-D-I-C iii -;
(SEQ ID NO: 12)
-C i -V-N-E-F-G-C ii -E-D-F-Y-D-I-C iii -;
(SEQ ID NO: 13)
-C i -F-N-E-F-G-C ii -E-D-F-Y-D-I-C iii -;
(SEQ ID NO: 14)
-C i -Y-N-E-Y-G-C ii -E-D-F-Y-D-I-C iii -;
and
(SEQ ID NO: 15)
-C i -Y-N-E-W-G-C ii -E-D-F-Y-D-I-C iii -.
9. The peptide ligand according to claim 1 , or a pharmaceutically acceptable salt thereof, which is a free acid or a sodium, potassium, calcium, or ammonium salt.
10. The peptide ligand according to claim 1 , or a pharmaceutically acceptable salt thereof, which is a high affinity binder of the human, mouse and dog MT1-MMP hemopexin domain, wherein the peptide ligand does not cross-react with MMP-1, MMP-2, MMP-15 and MMP-16.
11. A drug conjugate BT17BDC-18, which is of formula (IV):
wherein:
Toxin is the cytotoxic agent DM1;
Bicycle represents a peptide ligand comprising:
a polypeptide of the amino acid sequence:
(B-Ala)-Sar10-AC(D-Ala)NE(1Nal)(D-Ala)CEDFYD(tBuGly)C (SEQ ID NO: 5); and
a molecular scaffold which is TBMB (1,3,5-tris(bromomethyl)benzene), which forms covalent bonds with the cysteine residues of the polypeptide yielding a tri-substituted 1,3,5-trismethylbenzene structure;
R 3 represents methyl, and R 1 , R 2 and R 4 each represent hydrogen;
m represents 2; and
n represents 1,
or a pharmaceutically acceptable salt thereof.
12. A pharmaceutical composition comprising the drug conjugate according to claim 11 , in combination with one or more pharmaceutically acceptable excipients.