The second synthetic strategy to produce polymer prodrugs by RDRP is based on the grafting of the drug onto a monomer (resulting in a prodrug monomer) prior to its polymerization, also called "grafting through" method. RDRP techniques allow for a wide range of monomers bearing functional groups to be polymerized in a controlled fashion with no or negligible sidereactions involving these chemical groups. This strategy allows to insert drug moieties at predefined ratios on a single polymer chain and to achieve higher drug loadings by avoiding steric hindrance during drug conjugation usually encountered with the "grafting to" method.