Abstract: The present invention is directed toward the delivery of toxic agents to pathogenic cells, particularly cancer cells. In some embodiments, the toxic agent is a human ribonuclease or similar agent that is toxic to cells.

Abstract: The present invention relates generally to conjugates of human ribonucleases and water-soluble polymers, compositions comprising the conjugates and methods of using the same. In particular, the present invention provides conjugates of human ribonucleases and one or more water-soluble polymer compositions (e.g., to increase serum half-life and a pharmacokinetic profile, in vivo biological activity, stability, and/or reduce host immune response to the protein in vivo) as well as methods of using the conjugates in the therapy, treatment, and/or prevention of disease (e.g., cancer).