In this study, we provide a feasibility proof-of-principle of a non-invasive intranasal administration of BDNF and we report the effects of intranasal BDNF on the neurodegeneration observed in 6.5-month old AD11 anti-NGF mice [24], after neurodegeneration has already progressed significantly and cognitive deficits are apparent. The gene discussed is BDNF; the disease is Cognitive impairment.