The combination of enzyme-sensitivity and the possibility of performing PDT using polymer prodrugs obtained by the "grafting through" method has also been reported. The enzymesensitive monomer prodrug based on Ptx, MAAm-GFLG-Ptx, was polymerized from a POEGMA macro-RAFT agent leading to 130 nm P(MAAm-GFLG-Ptx)-b-POEGMA polymer prodrug nanoparticles able to physically encapsulate Chlorin e6 as the photosensitizer for PDT (Figure ). The presence of cathepsin B accelerated the release of Ptx in vitro, reaching 80 % after 8 h. In parallel, the loaded-photosensitizer was also quickly released, which was assigned to the disassembly of the nanoparticles. In vivo experiments on T24 bladder multicellular tumor spheroids and on T24 tumor-bearing mice showed significant antitumor efficacy due to the combination of Ptx chemotherapy and PDT.