Radiolabeled vasoactive intestinal peptide analogs for diagnosis and radiotherapy

摘要

The present invention encompasses radiolabeled peptide analogs of vasoactive intestinal peptide (VIP) labeled with a radionuclide useful for imaging target sites within mammalian living systems. The invention particularly provides radiolabeled VIP derivatives that bind selectively to the VIP receptor on target cells. Specifically, the invention relates to the radiolabeling of VIP-receptor specific agents and their subsequent use for radiodiagnostic and radiotherapeutic purposes. The invention encompasses methods for radiolabeling these peptides with radio-nuclides and the use of these peptides as scintigraphic imaging agents. The radiolabeled VIP derivatives of the present invention exhibit pharmacological activity and therefore are useful as either imaging agent for visualization of VIP-receptor positive tumors and metastases, as a radiodiagnostic agent or as a radio-therapeutic agent for the treatment of such tumors in vivo by specifically targeting the cytotoxic radionuclide selectively to the tumor site in mammalian living systems.