CONDITIONAL INTERNALIZATION OF PEGYLATED AGENTS BY PRETARGETING BI-SPECIFIC PEG-BINDING ANTIBODIES FOR DIAGNOSIS AND THERAPY

摘要

A monomeric bispecific polyethylene glycol (PEG) engager that includes an anti-PEG Fab fused to a disulfide stabilized scFv that specifically binds to a cell surface antigen. The PEG engager, in the absence of PEG, remains monomeric upon binding to the cell surface antigen on a cell and remains on the surface of the cell. Also provided is a method for treating cancer by administering a PEG engager followed by a PEGylated anti-cancer agent. A kit that contains a PEG engager and a PEGylated anti-cancer agent is also disclosed. Further disclosed are methods for imaging cells and diagnosing cancer by administering a PEG engager followed by a PEGylated imaging agent. Another kit is proivided that includes the PEG engager and the PEGylated imaging agent.