As for other routes of administration, recently, a new formulation of lipid nanoparticles for intranasal treatment of Parkinson disease using the glial-derived growth neurotrophic factor (GDNF) encapsulated in a chitosan (CS)-coated nanostructured lipid carriers (NLC), CS-NLC-TAT-GDNF, is in progress and has showed better brain delivery when compared to previous formulations [54]. Here, GDNF is linked to Parkinson disease.