Effect of OC459 on the Response to Rhinovirus Challenge in Asthma

Inclusion Criteria: * Age 18--55 years * Male or female * Clinical diagnosis of asthma for at least 6 months prior to screening * An Asthma Control Questionnaire (ACQ) Score \>0.75 * Positive histamine challenge test (PC20 \<8 µg/ml, or \<12 µg/ml and bronchodilator response ≥ 12%) * Worsening asthma symptoms with infection since last change in asthma therapy * Positive skin prick test to common aeroallergens (e.g. animal epithelia, dust mite) * Treatment comprising inhaled corticosteroids (ICS) or combination inhaler (Long -Acting Beta Agonist with ICS), with a daily ICS dose of at least 100mcg fluticasone or equivalent. * Participant is willing for their GP to be informed of their participation. * English speaker Exclusion Criteria: * Presence of clinically significant diseases other than asthma, which, in the opinion of the investigator, may either put the patient at risk because of participation in the trial, or diseases which may influence the results of the study or the patient's ability to take part in it * Smoking history over past 12 months * Seasonal allergic rhinitis symptoms at screening * Asthma exacerbation or viral illness within the previous 6 weeks * Current or concomitant use of oral steroids, anti--leukotrienes or monoclonal antibodies * Pregnant or breast-feeding women (patients should not be enrolled if they plan to become pregnant during the time of study participation) * Contact with infants \<6 months or immunocompromised persons, elderly and infirm…