Effects of block copolymer micelles on the pharmacokinetics of encapsulated drugs

Abstract Block copolymer micelles are among the most extensively studied drug delivery systems over the past three decades. They have been shown to enhance the aqueous solubility, control the release, and improve the targeting of the encapsulated drugs. Moreover, block copolymer micelles have shown to modify the toxicity profile of their cargo by changing their pharmacokinetic profile. The efforts in this field have resulted in several polymeric micellar formulations being evaluated in clinical trials. Among these formulations, a paclitaxel-loaded methoxy poly(ethylene oxide)-block-poly( d , l -lactide) (PEO-b-PDLLA) known as Genexol-PM (developed by Samyang Biopharmaceuticals) was approved for the treatment of different types of cancer in South Korea and other Asian countries. Furthermore, it is currently marketed in the European Union under the trade name Cynviloq. Although polymeric micelles were primarily intended to be used as intravenously administered drug carries, recent research has shown a potential benefit for polymeric micellar vehicles in modifying the pharmacokinetic profile of the encapsulated drug through other routes of administration such as oral, ocular, and transdermal. This chapter provides an overview of the effects of polymeric micelles on the pharmacokinetics of the encapsulated drug including those currently in clinical trials.