LABELLED PEPTIDE COMPOUNDS

摘要

The invention relates to a labelled peptide compound, wherein the peptide has a selective neurotensin receptor affinity and is represented by the general formula (I): R1 - (<1>Pro)n - <2>Xaa - <3>Xbb -<4>Xcc - <5>Xdd - <6>Xee - <7>Leu - OH, wherein R1 is a (C1-C3)alkanoyl group, an arylcarbonyl group, an aryl-(C1-C3)alkanoyl group, or a chelating group attached by an amide bond or through a spacing group to the peptide molecule; Xaa and Xbb are each individually Arg or Lys; Xcc is an unsubstituted or substituted cyclic amino acid, preferably selected from Pro and Hyp; Xdd is Tyr, Trp or Phe; Xee is Leu, Ile or t.-butylalanine; and n is 0 or 1; and wherein said peptide is labelled with (a) a metal isotope, or (b) with a radioactive halogen isotope; on the understanding that: (i) if the label is a metal isotope, R1 represents a chelating group for chelating said isotope; and (ii) if the label is a radioactive halogen isotope, said halogen isotope is attached to <4>Tyr in the 2-position of the phenyl ring, to <4>Trp, or to the aryl group of substituent R1. The invention further relates to a pharmaceutical composition comprising said labelled peptide compound, to the use of said composition for diagnosis and therapy, and to a kit for preparing a radiopharmaceutical composition.