title: Clinical trials of intranasal delivery for treating neurological disorders--a critical review.
abstract: BACKGROUND
  The intranasal delivery of therapeutics to the brain has achieved great success in preclinical studies. These findings are important because there are many neurological disorders without feasible treatments, due to a lack of effective drug delivery methods to the brain. Translating such intranasal delivery strategies from bench to bedside is an important step for curing these neurological diseases.
  
  
  METHODS
  This review summarizes recent clinical trials that have investigated the intranasal delivery of drugs to the brain to treat neurological disorders and their potential mechanisms of action. In addition, the potential opportunities as well as challenges of intranasal delivery in clinical trials are discussed.
  
  
  CONCLUSIONS
  The intranasal delivery of drugs to the brain is a novel method with great potential, and it may provide an extraordinary approach to overcome the existing barriers of drug delivery for treating some neurological disorders. Intranasal delivery of central nervous system therapeutics has shown promise in several clinical trials, which demonstrates both the need and importance of further research.
authors.affiliation: Nanjing University School of Medicine, Jinling Hospital, Department of Neurology, 305 East Zhongshan Road, Nanjing 210002, Jiangsu Province, China. xfliu2@yahoo.com.cn
authors.forename: Xinfeng
authors.initials: X
authors.lastname: Liu
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D002491:Central Nervous System Agents / Q000008:administration & dosage*; D002986:Clinical Trials as Topic; D006801:Humans; D009422:Nervous System Diseases / Q000188:drug therapy*
chemical_list: D002491:Central Nervous System Agents