Abstract:

Alzheimer’s disease (AD): AD, a neurodegenerative disorder and a significant cause of dementia throughout the world mostly affects the older adults but sometimes also seen in young age (early state AD). As per the Alzheimer Association report 2017, AD remains to be considered as the 6th leading cause of death which nearly touches around 5.5 million people only in the USA and the data is similar throughout the world (approximately 37 million people suffers from AD). On the other hand, the treatments are insufficient, and the available therapies do not claim the complete cure of disease. Instead, they relieve the symptoms in the preliminary stage. Also, AD therapies are very costly, mostly unaffordable for an average income population. Such constraint is due to the inaccessibility of the brain. The human brain is the most complex and delicate organ, highly protected by various physiological shields primarily the blood-brain-barrier (BBB). The BBB upholds the homeostasis of the brain and restricts the entry of most of the foreign components including lipids, peptides, and essential nutrients. Thus, the entry of almost all the drugs and bioactive to the brain remains complicated. The intranasal (IN) route offers an alternative approach for drug delivery to the brain without the interference of the BBB. In our previous article, we have discussed various innovative approaches, describing the novel techniques, efficiency, limitations, clinical investigations, patents, FDA status, current scenario and future possibilities of direct noseto-brain drug delivery.