Polymer conjugates for focal and targeted delivery of drugs

Polymer therapeutics is a very promising and rapidly growing area of nanomedicine, which has significantly improved the therapeutic potential of low-molecular-weight drugs and proteins for cancer treatment. Conjugation of toxic drugs to high-molecular-weight carriers can lead to reduction in systemic toxicity, longer retention time in the body, improved biodistribution and therapeutic efficacy, and site-specific passive accumulation thanks to the leaky tumor vasculature. Furthermore, a targeting moiety can be coupled to the polymer-drug conjugate in order to actively and selectively deliver it to the desired tissue and cellular target. This review presents a summary of currently developed polymer therapeutics with detailed focus on their components and supramolecular structure. The use of polymeric nanocarriers for cancer angiogenesis-targeted delivery is illustrated by specific examples.