Tumour targeting with alpha-active compounds of At-211

The principles for use of the alpha-emitter At-211 for tumour therapy are d iscussed. The use of alpha-emitters instead of beta-emitters for this purpo ses has the potential of providing a higher dose to the tumour with simulta neous lower dose to surrounding healthy tissue. Furthermore, beta-active co mpounds with tumour affinity has a much higher efficiency the corresponding beta-active compounds against single cell or micrometastatic cancer. Const raints and limitations of the method are discussed. Experiments with astati nated monoclonal antibodies as well as small molecules are described, as we ll as some possible strategies still not investigated.