Vienna Challenge Chamber Study Using RV658 in Subjects With Allergic Rhinitis

Inclusion Criteria: * Subject is healthy * History of seasonal allergic rhinitis * Male aged between 18 and 55 years * Body weight \>/= 50 kg with BMI in range 19 - 29 kg/m2 (inclusive) * Exhibits a moderate response to 4 hour exposure to grass pollen in the challenge chamber with a total nasal symptom score (TNSS) of \>/= 6 * Positive skin prick test (wheal \>/= 4 mm) for grass pollen * Positive total IgE result (RAST class \>/= 2) for grass pollen * Current non-smoker who has not used tobacco in the past 6 months with a pack history of \</= 10 pack years * Baseline FEV1 \>/= 80% and FEV1/FVC \>/= 70% of predicted values * No conditions or factors that may preclude subjects ability to remain in the challenge chamber for a period of 6 hours * capable of giving informed consent and is compliant with protocol requirements * available to complete all study measurements Exclusion Criteria: * structural nasal abnormalities or nasal polyps, history of frequent nosebleeds, recent nasal surgery or recent (within 3 weeks) or ongoing upper respiratory tract infection * history of drug allergy * participation in another clinical trial or has participated in a study using an NCE within the previous 3 months, or any clinical study within 1 month * taking regular (or a course of) medication whether prescribed or not, including steroids, vitamins, macrolides, anti-fungal agents and herbal remedies. Paracetamol (\</= 2g / day) and occasional short acting beta agonists are permitted * use of oral, injectable or dermal steroids within 5 weeks or intranasal and/or inhaled steroids within 1 week of the screening visit * past or present disease, which as judged by the investigator, may affect the outcome of the study * regular consumption of \> 21 units alcohol per week * infected with Hepatitis B, Hepatitis C, or HIV virus * current or chronic history of liver disease, or known hepatic or biliary abnormalities * positive test for drugs of abuse or alcohol at screening * previously known allergy to any of the active or inactive ingredients in the study medication * mentally or legally incapacitated * any other reason that the investigator considers makes the subject unsuitable to participate