Lessons learned from the COVID-19 pandemic: the intranasal administration as a route for treatment - a patent review.

The COVID-19 pandemic exposed the fragility of today's marketed treatments for respiratory infections. As a primary site of infection, the upper airways may represent a key access route for the control and treatment for these conditions. The present study aims to explore and identify, through a patent review, the novelty of therapies for COVID-19 that use the intranasal route for drug administration. A search was carried out in Wipo and Espacenet, using the descriptors 'COVID-19 OR SARS-CoV 2' AND 'treatment OR therapy' AND NOT 'vaccine OR immunizing' and the classification 'A61K9/0043'. Of the 151 patents identified, we excluded 73 duplicates, and 36 documents that meet the criteria adopted for exclusion (not nasally administered formulations, vaccines, post COVID-19 treatments, uncertain route of administration or form). We identified 78 unique patents on patent databases, of which 42 were selected for this review. The documents revealed the use of the intranasal pathway not only for drug repositioning but also for using plant-derived and biological molecules. Overall, the new formulations explore a variety of known drugs and natural products incorporated in drug carrier systems and devices for drug delivery and administration. Thus, the intranasal route remains a promising strategy for drug delivery, offering direct access to the primary infection site and warranting further exploration.