Anti-met therapy for previously diagnosed cancer patients

A method of assisting in determining whether or not a patient previously diagnosed with cancer, is susceptible to anti-Met therapy, said method comprising:

• (i) administering an imaging agent which comprises an 18F-radiolabelled c-Met binding cyclic peptide to said patient;
• (ii) using positron emission tomography (PET) imaging at least one site of said cancer of said patient with the imaging agent of step (i);
• (iii) determining from the imaging of step (ii) whether or not there is elevated uptake of said imaging agent at said site;
• (iv) when step (iii) shows elevated uptake, said patient is susceptible to said anti-Met therapy;
• (v) when step (iii) shows no elevated uptake, said patient is not susceptible to said anti-Met therapy;
• wherein said c-Met binding cyclic peptide is an 18 to 30-mer cyclic peptide of Formula I:
• Z1-[cMBP]-Z2 (I)
• where:
• cMBP is of Formula (II):
• -(A)x-Q-(A′)y- (II)
• where Q is the amino acid sequence (SEQ-1), (SEQ-2), or (SEQ-3):
• wherein SEQ-1 is -Cysa-X1-Cysc-X2-Gly-Pro-Pro-X3-Phe-Glu-Cysd-Trp-Cysb-Tyr-X4-X5-X6-;
• wherein SEQ-2 is Ser-Cysa-X1-Cysc-X2-Gly-Pro-Pro-X3-Phe-Glu-Cysd-Trp-Cysb-Tyr-X4- X5-X6;
• wherein SEQ-3 is Ala-Gly-Ser-Cysa-X1-Cysc-X2-Gly-Pro-Pro-X3-Phe-Glu-Cysd-Trp-Cysb-Tyr-X4-X5-X6-Gly-Thr;
• wherein X1 is Asn, His or Tyr;
• X2 is Gly, Ser, Thr or Asn;
• X3 is Thr or Arg;
• X4 is Ala, Asp, Glu, Gly or Ser;
• X5 is Ser or Thr;
• X6 is Asp or Glu;
• and Cysa-d are each cysteine residues wherein residues a and b as well as c and d are cyclised to form two separate disulfide bonds;
• A and A′ are independently any amino acid other than Cys, with the proviso that at least one of A and A′ is present and is Lys;
• x and y are independently integers of value 0 to 13,
• wherein [x+y]=1 to 13;
• Z1 is attached to the N-terminus of cMBP, and is H or MIG;
• Z2 is attached to the C-terminus of cMBP and is OH, OBc, or MIG,
• where Bc is a biocompatible cation;
• each MIG is independently a metabolism inhibiting group which is a biocompatible group which inhibits or suppresses in vivo metabolism of the cMBP peptide;
• wherein MIG comprises at least one of N-acylated groups —NH(C═O)RG, carboxamide, tert-butyl ester, benzyl ester, cyclohexyl ester, amino alcohol or a polyethyleneglycol (PEG) building block;
• wherein the acyl group —(C═O)RG has RG selected from the group consisting of C1-6 alkyl, C3-10 aryl groups and comprises a polyethyleneglycol (PEG) building block;
• wherein cMBP is labelled at the Lys residue of the A or A′ groups with 18F.