Nanoparticulate drug delivery systems to overcome the blood-brain barrier

Abstract

Nanomedicine, the term used to describe the combination of nanotechnology (or nanoparticles) with medicine, is now being used in the medical field worldwide. Researchers in the field of nanomedicine have been developing drug delivery strategies to overcome the blood-brain barrier (BBB) and have been investigating methods for penetrating the BBB for decades. However, effective nanoparticle-based formulations that successfully penetrate the BBB and reach the target site (e.g., brain cancer) in the brain have not yet been developed. In contrast, several drug-loaded nanoparticle formulations delivered via the systemic route have been approved by the FDA to treat various types of cancers. This review first discusses FDA-approved nanomedicines, including liposomal formulations of Doxil® and the albumin-based drug Abraxane®. Their characteristics are discussed, as are the challenging issues in the development of nanomedicine. Subsequently, recent progress toward nanoparticle-based formulations that have succeeded in delivering drugs to the brain is reviewed. The approaches used to overcome the BBB, including receptor-mediated transcytosis and other attractive strategies, are discussed. This information can be useful in understanding nanoparticle-based drug delivery to brain tissue and can provide hints for next-generation nanoparticle-based drug delivery systems and the future of personalized therapy.