Synairgen's shares dive after AstraZeneca returns AZD9412 rights

Shares in Synairgen plummeted almost 50% after AstraZeneca opted to return rights on drug AZD9412 (inhaled interferon beta), which did not meet the pharma giant's predefined criteria for progression in a trial.

Syanairgen said it would further analyse the data and determine future development routs.

"Cold infections did not affect trial patients' asthma in the INEXAS study as much as predicted, meaning that the drug's effects on severe exacerbations could not be determined," said Synairgen.

"Treatment with AZD9412 switched on antiviral responses in the lungs, improved morning peak flow (a measure of lung function), and was well tolerated."

Chief executive Richard Marsden remained positive about the potential of inhaled interferon beta, particularly for patients with COPD who suffer due to respiratory viruses.

2Once we have completed the data analysis, we will provide an update on the programme and our plans for future development," said Marsden in a statement.

At 13:13 BST, shares in AIM-traded Synairgen were down 47.12% to 13.75p each.