A Study to Investigate the Impact of Dose and Dosing Frequency of AZD8848 on the Response on Biomarkers

Inclusion Criteria: * Healthy men or women aged 18 to 55 years (inclusive). Women must be of non-childbearing potential or must have been stable on a highly effective contraceptive method for at least 3 months prior to Visit 1 and be willing to continue on the chosen contraceptive method, with additional use of a condom by male partners, until 3 months after last dose. * Female subjects should have a negative pregnancy test at Visit 2 and date of last menstruation consistent of non-pregnancy * Ability to metabolise AZD8848 (an in vitro screening assay will determine metabolic activity in a blood sample taken at Visit 1 using a pre-defined limit) Exclusion Criteria: * Any clinically significant disease or disorder * Any clinically relevant abnormal findings in physical examination * Structural abnormalities of the nose or nasal disorder symptomatic enough to cause significant nasal obstruction * Ongoing pregnancy or lactation * Abnormal immune function