Immunoconjugates and methods for their use in tumor therapy

摘要

Novel pH-sensitive immunoconjugates which dissociate in low-pH tumor tissue, comprising a chemotherapeutic agent and an antibody reactive with a tumor-associated antigen are described. The chemotherapeutic agent is coupled to the antibody by a link which is unstable in low pH. The link may comprise a spacer consisting of a polyamino acid. Representative antibodies for use in these immunoconjugates include monoclonal antibodies which are not internalized by tumor cells.