The body’s blood-brain barrier is a wonderful thing, allowing essential nutrients into the brain, but keeping dangerous bacteria out. Unfortunately, it also blocks some of the drugs that have the potential to treat or cure central nervous system disorders, such as Alzheimer’s, Parkinson’s, multiple sclerosis and epilepsy. Seattle-based Impel Neuropharma is developing a noninvasive intranasal technology—a pressurized aerosol, far beyond the capabilities of a nasal spray—that delivers biologics for otherwise difficult-to-treat brain diseases. In April, after five years of working with animal data, Impel Neuropharma announced it had received positive results for its intranasal technology from a study of seven human subjects. Launched by two University of Washington graduate students, Impel was created as a spin-off from Dr. Rodney Ho’s lab in the Pharmaceutics Department.