Provided are binding polypeptides (e.g. antibodies), and drug conjugates thereof comprising an Fc domain with an altered glycosylation profile and reduced effector function. In particular embodiment, the Fc domain comprises: an asparagine residue at amino acid position 298, according to EU numbering； and a serine or threonine residue at amino acid position 300, according to EU numbering. Also provided are nucleic acids encoding the antigen binding polypeptides, recombinant expression vectors and host cells for making such antigen binding polypeptides. Methods of using the antigen binding polypeptides disclosed herein to treat disease are also provided.
