Drug-Impregnated Polymer Delivery

Primary or metastatic brain tumors are challenging to treat due to their aggressive and heterogenic characteristics and the limited availability of drugs and tools capable of permeating the blood-brain barrier (BBB). A vast array of methods has been explored to bypass these physical limitations, but over the past few decades only a small portion of these techniques and compounds have been translated into clinical practice. In this chapter, we focus our attention on different ways to efficiently deliver drugs across the BBB and enumerate some of the roadblocks to efficacious treatment. First, we briefly review the anatomic and functional barriers that prevent the diffusion of therapeutics in the central nervous system, which will clarify the unique challenges of brain tumor therapy. We then describe preclinical models and the clinical experience of polymeric drug delivery and practical applications for both primary and metastatic brain tumors.