Pegylation of linkers improves antitumor activity and reduces toxicity of immunoconjugates

摘要

The present invention is directed to the site-specific PEGylation of immunoconjugates. In particular, the present invention provides immunoconjugates wherein a connector molecule attaching a targeting molecule to an effector molecule is conjugated to one or more polyethylene glycol molecules. The present invention further provides methods for increasing the antitumor activity of an immunotoxin, comprising attaching in a site-specific manner one or more polyethylene glycol molecules to a linker connecting a toxic moiety to a targeting moiety of an immunotoxin.