Polymer Therapeutics: Concepts and Applications

Abstract

Polymer therapeutics encompass polymer–protein conjugates, drug–polymer conjugates, and supramolecular drug‐delivery systems. Numerous polymer–protein conjugates with improved stability and pharmacokinetic properties have been developed, for example, by anchoring enzymes or biologically relevant proteins to polyethylene glycol components (PEGylation). Several polymer–protein conjugates have received market approval, for example the PEGylated form of adenosine deaminase. Coupling low‐molecular‐weight anticancer drugs to high‐molecular‐weight polymers through a cleavable linker is an effective method for improving the therapeutic index of clinically established agents, and the first candidates have been evaluated in clinical trials, including, N‐(2‐hydroxypropyl)methacrylamide conjugates of doxorubicin, camptothecin, paclitaxel, and platinum(II) complexes. Another class of polymer therapeutics are drug‐delivery systems based on well‐defined multivalent and dendritic polymers. These include polyanionic polymers for the inhibition of virus attachment, polycationic complexes with DNA or RNA (polyplexes), and dendritic core–shell architectures for the encapsulation of drugs. In this Review an overview of polymer therapeutics is presented with a focus on concepts and examples that characterize the salient features of the drug‐delivery systems.