The invention generally relates to zwitterionic polymers (including zwitterionic copolymers), such as polymethacrylic structures, with pendent functional moieties, such as therapeutic or biologic moieties. More particularly, the invention relates to phosphorylcholine-substituted methacrylic polymers prepared by free radical polymerization and click chemistry, for example, and compositions and products comprising same, as well as related methods and uses of the compositions, for example, as biological or therapeutic agents and in drug delivery thereof.