Formulation and device design to increase nose to brain drug delivery

A major limiting factor for the treatment of central nervous system (CNS) related disorders is the inability for drug substances to cross the blood-brain barrier. Some medications may possess dose-limiting systemic side effects that hinder their ability to reach maximum effective concentrations in the CNS. Over the last several decades, scientists have studied the ability for drugs to be transported from the nose directly to the brain, and compared to intravenous injections, many studies have reported higher brain concentrations from formulations administered intranasally. The primary focus of this paper is to review the formulation and device approaches that have been reported to increase drug delivery into the CNS through the nose-to-brain delivery pathway.