A typical example reported the coupling of SMA with the hydroxyl groups of Cpt and of the kinase inhibitor dasatinib (Dt). These monomer prodrugs were then copolymerized with OEGMA by the RAFT process to produce the corresponding P(SMA-ester-Dt-co-OEGMA) and P(SMA-ester-Cpt-co-OEGMA) hydrophilic polymer prodrugs. P(MAA-co-DMAEMA)-b-P(SMAester-Dt) amphiphilic diblock copolymer prodrug nanoparticles of 43 nm in diameter were also prepared by copolymerization of tert-butyl methacrylate (tBMA) with DMAEMA from a P(SMAester-Dt) macro-RAFT agent, to evaluate the effect of polymer morphology on drug release kinetics. It was shown that release of Dt was slightly accelerated in pH 5.8 buffer compared to pH 7.4. In addition, while the prodrug nanoparticles gave higher drug loadings compared to the hydrophilic prodrugs (44.0 and 32.5 wt %, respectively), they showed more sustained drug release in human serum (50 % Dt released after 384 h and 240 h, respectively). This is due to the localization of the Dt groups in the hydrophobic core of the nanoparticles, which reduces the cleavage of ester functions, compared to when the drug is randomly distributed along a solvated polymer chain. Greater uptake and retention of the prodrug nanoparticles in K562-R1 cells compared to the free Dt was shown, as well as significant accumulation in the tumor after 24 h. Interestingly, copolymer prodrugs containing both drugs prepared by terpolymerization of OEGMA, SMA-ester-Cpt and SMA-ester-Dt (P(SMA-ester-Cpt-co-SMA-ester-Dt-co-OEGMA)), gave greater cytotoxicity in vitro on K562-S cells, compared to P(SMA-ester-Dt-co-OEGMA).