The World Health Organisation (WHO) estimates that more than a billion people worldwide are suffering from diseases of the CNS. AD is the most common neurodegenerative dementia in the industrialised world, with prevalence rates well over 30% in the over 80-years-old population. AD causes enormous costs to the social healthcare systems, as well as personal tragedies for the patients, families and caregivers. Like most neuro-degenerative diseases AD has a poor prognosis and only symptomatic therapy is currently available. Efficient treatment strategies are still limited and an ageing society in demographic change presents an enormous chal-lenge to the health systems of industrialised nations. A highly critical point in that context is the low central availability of drugs due to the blood brain barrier (BBB) and nearly all of the larger molecules such as peptides and proteins fail to cross the BBB. The current state-of-the-art to deliver drugs with a low central bioavailability is intrathecal, intracerebroventricular or intraparenchymal injections. They are used to deliver drugs directly to the CSF of the CNS, some of them being given chronically via an implanted intrathecal micropump. Although, such delivery systems are well established, these routes of administration are invasive, require a surgery with high risks, have a lower patient compliance and can be poorly controlled.
Intranasal nose to brain (N2B) delivery to the upper third of the nasal cavity bypasses the BBB to rapidly target therapeutics to the CNS along the olfactory and trigeminal neural pathways.
Further reading link: https://scholar.google.de/citations?user=FYpbg1MAAAAJ&hl=de