A Patent Review on Nanotechnology-Based Nose-to-Brain Drug Delivery

Background: Current cerebral drug delivery to the brain and Cerebrospinal Fluid (CSF) is limited by the Blood-Brain Barrier (BBB) or the blood-blood Cerebrospinal Fluid (CSF) barrier. The popular, non-invasive, intranasal delivery provides an exciting route for topical and systemic applications. For example, intranasal drug delivery of Central Nervous System (CNS) drugs can be designed to pass the BBB barrier via the nose-to-brain pathways. Recent nanotechnology research and patenting focus mainly on overcoming typical limitations including bioavailability, transport, BBB penetration, targeted delivery, controlled release rate and controlled degradation. Objective: The aim of the present study was to assess the state-of-the-art of nose-to-brain drug delivery systems and the role of nanotechnology in targeted delivery for the treatment of CNS and related therapeutic conditions. Methods: Patent and related searches were made with analytics to explore and organize nanotech work in intranasal drug delivery to the brain. Technical advancements were mapped by API, formulation and performance criteria. Patents and published patent applications were searched with concept tables of keywords, metadata (e.g., assignee) and patent classes (e.g., International Patent Classes and Cooperative Patent Classes). Results: The reviewed patents and published applications show a focus on formulations and therapeutic indications related to the nano-based nose-to-brain drug delivery. The main patented materials were surface modifiers, delivery systems and excipients. Conclusion: Surface modified nanoparticles can greatly improve drug transport and bioavailability of drugs, particularly higher molecular weight drugs. The most commonly used surface modifiers were chitosan, lectin and cyclodextrin-cross-linker complex. Nanoformulations of herbal drugs could increase drug bioavailability and reduce toxicity. Biotechnology-related drug delivery approaches such as monoclonal antibodies and genetically engineered proteins (molecular Trojan horses) deliver large molecule therapeutics.