A paper has just come out in Macromolecular Rapid Communications highlighting the potential benefits of cyclodextrin-based macromolecular systems as cholesterol-mopping therapeutic agents in Niemann-Pick disease type C (NPC).
Although promising, the current treatment of NPC based on chemical modification of monomeric CD suffers from poor pharmacokinetics and bioavailability particularly in the brain. CDs in fact do not seem to effectively cross the blood-brain barrier (BBB). Moreover, in order to obtain a sufficient therapeutic effect, high doses of CDs are typically required because systemically administered CDs have a short half-life in the bloodstream owing to its rapid renal clearance.
Overcoming some of these limitations is possible by embedding the CD macrocycle into a larger macromolecular architecture. Cyclodextrin-based polymers have three main advantages: 1) the higher molecular weight of the polymer could translate into retardation of renal clearance, thus prolonging blood half-life of the system; 2) the oligomers of CDs are more easily excreted through the renal tubules without degradation; and 3) when assembled into nanoparticles, CDs have been shown to exploit the carrier-mediated transcytosis pathway found in the BBB for brain drug delivery via systemic administration.