Dr Omid Farokhzad talks to ecancertv at the UK's National Cancer Research Institute ( NCRI ) 2013 meeting about the use of polymeric nanoparticles for cancer drug delivery.

A variety of organic/inorganic materials are utilised to generate nanoparticles for drug delivery: Polymeric nanoparticles, dendrimers, nanoshells, liposomes, nucleic acid based nanoparticles, magnetic nanoparticles, and virus nanoparticles.

Two most commonly used systems are polymeric nanoparticles and liposomes. Controlled release polymer technology impacts every branch of medicine: Ophthalmology, pulmonary, pain medicine, endocrinology, cardiology, orthopedics, immunology, neurology and dentistry, with several of these systems in clinical practice such as Atridox, Lupron Depot, Gliadel, Zoladex, Trelstart Depot, Risperidol Consta and Sandostatin LAR. The market of controlled release polymer systems extended beyond drug delivery is estimated at $100 billion and are used by over 100 million people a year.

Polymeric nanoparticles deliver drugs in the optimum dosage over time, increasing the efficacy of the drug, maximising patient compliance and enhancing ability to use highly toxic, poorly soluble, or relatively unstable drugs. These systems can also be used to co-deliver two or more drugs for combination therapy.

The surface engineering of these nanoparticles may yield them ‘stealth’ to prolong their residence in blood and the functionalisation of these particles with targeting ligands can differentially target their uptake by a subset of cells, increasing their specificity and efficacy. The successful clinical translation of therapeutic nanoparticles requires optimisation of many distinct parameters including: Variation in the composition of the carrier system, drug loading efficiency, surface hydrophilicity, surface charge, particle size, density of possible ligands for targeting, etc., resulting in a large number of potential variables for optimisation which is impractical to achieve using a low throughput approach. Recently, combinatorial approaches have been developed to precisely engineer nanoparticles and screen multiple nanoparticle characteristics simultaneously. Our goal is to review efforts in design and optimisation of polymeric nanoparticles for medical applications, which formed the foundation for the clinical translation of the first-in-human targeted and controlled-release nanoparticles (BIND-014) for cancer therapy.