British drugs maker AstraZeneca has signed a licence agreement with AIM-listed Synairgen for the development of SNG000l, a treatment for respiratory tract viral infections in patients with severe asthma.Under the deal, FTSE 100-listed Astra will pay Synairgen a $7.25m up-front fee and potential development, regulatory and commercial milestones of up to $225m, in addition to tiered royalties on commercial sales. Early next year, Astra will begin a study into the effectiveness of the drug in patients with the disease. SNG000l also has potential as a treatment for other respiratory conditions, the group said. Head of Respiratory, Inflammation & Autoimmune Innovative Medicines at Astra, Maarten Kraan, said: "Respiratory disease is a core therapeutic area for AstraZeneca, and a key growth platform for the company. "Our approach includes addressing associated complications that patients experience, as well as developing treatments for the underlying disease. SNG001 is an innovative and targeted therapy that has, if successful, the potential to offer a step-change in the treatment of severe asthma, and possibly COPD."NR