A repackaged cancer drug finds its way

Cancer Therapy The recent success of immunotherapy has energized the clinical oncology field, yet for many cancer types, cytotoxic drugs remain the only treatment option. One such drug, doxorubicin (Dox), is very effective but also very toxic to healthy tissues when administered at the doses needed to kill tumor cells. To target delivery of the drug, Xu et al. developed a “nanoparticle generator” (iNPG) containing a polymeric form of Dox. The design features of iNPG ensure that it selectively accumulates at the tumor and that release of Dox is slow and sustained, resulting in high drug concentrations within the tumor. In mouse models of breast cancer, iNPG induced regression of lung metastases and was less toxic than other forms of Dox. Nat. Biotechnol. 10.1038/nbt.3506 (2016).