The present invention relates to the chemical modification of single chain
polypeptides by means of covalent attachment of strands of poly(ethylene
glycol) PEG and similar poly(alkylene oxides) to single chain polypeptide
binding molecules that have the three dimensional folding and, thus, the
binding ability and specificity, of the variable region of an antibody.
Such preparations of modified single chain polypeptide binding molecules
have reduced immugenicity and antigenicity as well as having a longer
halflife in the bloodstream as compared to the parent polypeptide. These
beneficial properties of the modified single chain polypeptide binding
molecules make them very useful in a variety of therapeutic applications.
The invention also relates to multivalent antigen-binding molecules
capable of PEGylation. Compositions of, genetic constructions for, methods
of use, and methods for producing PEGylated antigen-binding proteins are
disclosed.
