Evaluation of Safety, Side Effects and How the Drug CHF6467 Administered Via Intranasal Route is Absorbed, Modified and Removed in Healthy Subjects

A clinical trial to investigate the safety and tolerability of single and multiple intranasal (through the nose) dosing with the study drug CHF6467 in 68 healthy adult subjects. The study will investigate also how CHF6467 moves and behaves in the blood and in the fluid around the brain and spinal cord (cerebrospinal fluid) and if the drug CHF6467 causes an immune response by looking for specific molecules, called antibodies that may form against it. The study will be divided into two parts - Part 1 (testing single ascending doses of the study drug, SAD, lasting 4 days) and Part 2 (testing repeated or multiple ascending doses of the study drug, MAD, lasting 11 days). Each part of the study consists of a screening period, when eligible healthy volunteers will be selected, a treatment period, during which the study drug administration will take place and a follow-up period.