JiYong Lee

This chapter reviews commercialization efforts of microneedles (MNs) in various applications. Because of convenience, minimal invasiveness, and effectiveness, MNs have been developed extensively for transdermal drug delivery over two decades. Clinically, meaningful research outcomes have accelerated development of MN technology for commercialization. Two types of MN injection, disposable unit with applicator and integrated system, were introduced to the market as alternatives to conventional intradermal injections. Fully commercialized MN patches have also been developed such that they can be self-administered with ease of use for vaccination and cosmetics. MN technology was combined with electroporation or endovascular catheter balloon for enhanced transdermal or endovascular drug delivery. Continuous glucose monitoring for interstitial fluid measurements is another promising commercial MN application. Furthermore, many new applications are still in clinical trials, such as ocular MNs, dental MNs, radio-frequency MNs, and microneedling for collagen induction.