Radiopharmaceuticals for targeted radiotherapy of cancer

Targeted radiotherapy is the administration of 3 radiolabelled molecule des igned to deliver therapeutic doses of radiation to malignant tumours with h igh specificity. Radionuclides tl-lat are used to label radiopharmaceutical s ;for cancer therapy generally decay by particle emission, i.e., alpha, be ta(-), beta(+), Auger or conversion electrons. Bifunctional chelators have been designed to attach, metal radionuclides to biological molecules that t arget rumours. Four types of targeted radiotherapy agents are discussed: sm all molecules, carrier particles, receptor-targeted agents and pre-targetin g agents. Human trials of targeted radiotherapy for radiolabelled somatosta tin analogues and pre-targeting agents are encouraging. This review focuses on selected disclosures in the patent literature, primarily between 1993 a nd 1999, for radionuclide production, bifunctional chelators and radiopharm aceuticals, which may prove successful in the development of future agents for cancer radiotherapy.