An enzymatic method is provided for restructuring an affinity ligand bound heterogenous glycoform antibody sample to a substantially homogenous single desired glycoform antibody sample for therapeutic uses and kits for performing the methods. A method for enzymatically altering the Fc region of an affinity ligand bound antibody from a heterogenous glycoform to a substantially homogenous single glycoform comprises: contacting the affinity ligand bound heterogeneous glycoform antibody with a reaction buffer designed for a particular glycoform modification for a time sufficient and under conditions to modify the glycoform of the Fc region to a substantially homogeneous single form optionally adding one or more nucleotide sugars and/or cofactors and releasing the substantially homogeneous single glycoform antibody sample from said affinity ligand. The invention also encompasses biopharmaceuticals comprising single glycoform mAbs and polyclonal antibodies enzymatically produced for the treatment of cancers and immune disorders as well as compositions comprising the single glycoform antibodies as a biopharmaceutical.
