The blood-brain barrier is an unmet medical problem, especially for biologicals. The delivery of drugs through the nose into the brain (nose to brain, N2B) is known, however, today no appropriate technical solutions are available for more complex biologicals. The aims of this project are a mechanistic and pharmacokinetic study of the N2B-transport, prevention of immunogenicity during nasal administration, development of strategies for applied therapeutic implementation and a comparison of N2B efficiency with transcytosis-based drug delivery methods.