To Investigate the Safety, Pharmacodynamics and Effect on Allergic Reactivity of the Toll-like Receptor 7 (TLR7) Agonist GSK2245035 in Subjects With Respiratory Allergies

The purpose of this study is to examine the safety and effects on the immune system of treatment with GSK2245035 in subjects who suffer from nasal symptoms caused by an allergy to pollen or perennial allergen, with or without mild asthma. In addition, the effect of treatment with GSK2245035 on the body's allergic response in test situations will be explored. Approximately 28 subjects will receive GSK2245035 (up to 14 subjects each receiving 80 nanograms \[ng\] GSK2245035 and up to 14 subjects each receiving 20 ng GSK2245035) and 14 subjects will receive the dummy drug (placebo) during the study. Assignment of a subject to GSK2245035 or placebo will be done by chance, like flipping a coin. Neither the subjects nor the clinic staff will know whether a subject is being dosed with GSK2245035 or placebo during the course of the study. The study will include (a) Screening phase where the eligibility of subjects for enrolment will be assessed (b) Treatment phase during which subjects will receive either 8 nasal sprays of GSK2245035 80 ng or a matching placebo once weekly for 8 weeks (each dose will be split between the two nostrils). Subjects participating in this study in 2014 will receive a reduced dose of 20 ng i.n. of GSK2245035 once weekly for eight administrations (c) Follow-up period where any GSK2245035 induced changes to the immune system and the effect of treatment on the body's allergic response in test situations will be monitored. The maximum planned study duration for all subjects, including the screening, treatment and follow-up periods, is approximately 180 days.