The international Phase 2 trial of a synthetic anti-viral 'interferon', inhaled via a nebuliser, proved most effective in helping patients with more difficult asthma when they developed a virus or cold-induced attack.
Interferons are proteins that effectively 'interfere' with a virus's ability to interact with host cells and then spread. They also occur naturally as part of the body's immune response.
Present treatments "partially effective"
"We're not interested in curing the common cold – or rhinovirus as it's known – we want to limit the negative effect it has on asthma," Conjoint Professor Peter Wark, co-director of the University of Newcastle's Priority Research Centre for Asthma and Respiratory Diseases, said.
"Around 80 per cent of acute exacerbations are triggered by respiratory tract infections and our existing treatments are, at best, only partially effective."
The Phase II trial, conducted in Newcastle, Sydney, Melbourne and eight sites in the United Kingdom, in association with the University of Southampton and Imperial College London, asked patients to send an SMS text at the onset of cold-like symptoms. Patients were then assessed within 24 hours and administered either the interferon or a placebo.
The results, published in the American Journal of Respiratory and Critical Care Medicine, have encouraged the researchers to further explore the susceptibility and response factors.
Targeted to treat most critical respiratory conditions
"We didn't see a large benefit in everyone with asthma, especially those with already mild asthma," Professor Wark said.
"But in those whose asthma was more severe and difficult to control, the response was far better – we saw a significant reduction in their asthma exacerbation.
"The question is where we go from here. People who are most at risk of virus-related acute asthma are not well defined and we think more work needs to be done."
A follow-up trial, starting soon, will aim to determine which patients respond better to the therapy while also looking for biomarker signatures.
Professor Wark believes nebulised interferon could be applied to other patients with chronic respiratory diseases that suffer from recurring viral infections, including cystic fibrosis and COPD (Chronic Obstructive Pulmonary Disorder).
The therapy is being developed by Hunter Medical Research Institute (HMRI) and UK-based respiratory researchers.
