Development of nanomedicine based on fine-tuning synthetic polymers
Our motivation is "Transforming medical care through polymer-based nanomachines". The research story has become an article. Click here to read it!
Development of new drugs depends on the drug discovery & development processes including the target discovery, combinatorial synthesis and screening of drug candidates and identification of lead compounds. In addition, new drugs should pass the efficacy / safety test in animals and clinical evaluation in the patients for their approval for clinical use. Only 0.011% of drug candidates can progress to clinical evaluation and finally 0.003% can be approved. Also, the current drug discovery & development processes require huge costs reaching several billion US dollars and time more than ten years. Furthermore, it is getting more difficult to obtain new drugs by such processes.
Recent advances in biotechnology allow to develop various functional molecules including targeting molecules such as aptamers, peptides and antibodies, and their application in medicine is strongly demanded. On the other hand, the development of stimuli-responsive smart materials has recently been receiving increasing attention in the fields of materials science / nanotechnology. These smart materials are also expected to be used in medicine. However, there seems to be an obstacle for such applications.
To overcome the above-mentioned situations, we have studied the new concept of drug development based on fine-tuning synthetic polymers. In the design of polymeric drugs, the active moieties (drugs) and various functional molecules are conjugated to the platform of synthetic polymers, leading to enhancing drug functions. Importantly, the basis of developing such polymeric drugs is the precision polymerization (living polymerization) technology to control the primary structure (molecular weight, compositions and position of functional groups) of synthetic polymers. In the Polymer Chemistry Division (Prof. Nishiyama’s Laboratory) in Chemical Resources Laboratory, we integrate the targeting functionality, stimuli-responsive functionality and drug conjugating functionality into a single polymer chain, thereby aiming to realize multifunctional polymeric drugs (smart nanomedicine). Our targets include realization of effective but non-toxic cancer treatment, practical use of emerging biomedicine, biofunctional imaging and minimally invasive surgery in combination with medical instruments (Fig.1).