Intranasal delivery: circumventing the iron curtain to treat neurological disorders

Abstract

Introduction: The blood–brain barrier (BBB) is like an iron curtain that prevents exogenous substances, including most drugs, from entering the CNS. Intranasal delivery has been demonstrated to circumvent the BBB due to the special anatomy of the olfactory and trigeminal neural pathways that connect the nasal mucosa with the brain and the perivascular pathway within the CNS. In the last two decades, the concepts, mechanisms and pathways of intranasal delivery to the CNS have led to great success both in preclinical and clinical studies. More researchers have translated results from bench to bedside, and a number of publications have reported the clinical application of intranasal delivery.

Areas covered: This review summarizes results from recent clinical trials utilizing intranasal delivery of therapeutics to explore its pharmacokinetics and application to treating neurological disorders. Moreover, existing problems with the methods and possible solutions have also been discussed. The promising results from clinical trials have demonstrated that intranasal delivery provides an extraordinary approach for circumventing the BBB. Many drugs, including high-molecular-weight molecules, could potentially improve the treatment of neurological disorders via intranasal administration.

Expert opinion: Intranasal delivery is a novel method with great potential for delivering and targeting therapeutics to the CNS to treat neurological disorders.

Keywords:

• clinical trial
• intranasal delivery
• neurological disorders

Declaration of interest

This study was supported by the National Science Foundation of China (31200817, 81471181 and 31171016) and Jiangsu Provincial Special Program of Medical Science (BL2013025). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Notes

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