This invention relates to novel analogs of pituitary adenylate cyclase-activating polypeptide (PACAP), which are agonists for the PACAP/vasoactive intestinal peptide (VIP) receptors: PAC1, VPAC1 and VPAC2 receptors. These PACAP analogs can be used as prophylactic/therapeutic agents for a wide range of medical disorders, including (but not limited to) cancer and autoimmune disease. These PACAP analogs can be coupled to suitable radionuclides and used in the localization, diagnosis and treatment of disseminated cancers and metastatic tumors, or coupled to small molecule therapeutics and used as vectors for targeted drug delivery. This invention also provides pharmaceutical compositions of one or more PACAP-like compounds of the invention either alone or in combination with one or more other prophylactic/therapeutic agents.
