AstraZeneca has announced that The Lancet Respiratory Medicine has published encouraging safety and efficacy data from a Phase IIa study evaluating its novel investigational monoclonal antibody benralizumab in patients with chronic obstructive pulmonary disease (COPD).

The study, conducted by MedImmune, the company's global biologics research and development arm, evaluated the safety and efficacy of benralizumab in 101 adults with moderate-to-severe COPD and experiencing at least one acute exacerbation requiring oral corticosteroids, antibiotics, or hospitalisation in the past year. The overall patient population for the study was selected on the basis of elevated levels of eosinophils in sputum. The primary endpoint in the study was not met, as benralizumab did not reduce the acute exacerbation rate compared with placebo in the overall patient population. However, benralizumab demonstrated clinically significant improvements in lung function in the overall population.

In addition, in the pre-specified analyses, the study indicated that benralizumab reduced COPD exacerbations and improved other symptoms of COPD in certain patient groups. Patients treated with benralizumab who had higher baseline levels of eosinophils in their blood showed greater improvements in COPD symptoms, including exacerbation rate, lung function and disease-specific health status as measured by the Saint George's Respiratory Questionnaire-COPD (SGRQ-C) versus placebo-treated subjects.

There was a higher incidence of serious treatment-emergent adverse events (TEAEs) in the benralizumab group compared with placebo (14 vs 9). Overall, TEAEs were similar across treatment and placebo groups.

These data were presented in a poster session at the 2014 European Respiratory Society (ERS) International Congress in Munich, Germany, on 8 September 2014, along with key data from AstraZeneca's broad respiratory portfolio.

Benralizumab is an anti-interleukin-5 receptor alpha monoclonal antibody that depletes blood and sputum eosinophils, a type of white blood cell. Elevated levels of eosinophils are associated with the cause and severity of COPD attacks, as well as asthma and asthma exacerbations. Eosinophilic airway inflammation is believed to be present in between 20 and 30 percent of the 210 million people who suffer from COPD worldwide.

"Benralizumab is the first biological agent to show marked reduction in eosinophilic inflammation and beneficial effects in COPD, indicating a potential new way to treat patients with severe COPD symptoms," said lead investigator Professor Christopher Brightling, University of Leicester, Glenfield Hospital, Department of Respiratory Medicine. "The strength of these results reinforces the further development of this molecule for COPD."

"COPD is a highly heterogeneous disease and we are working to better understand patient subtypes, identify potential biomarkers and tailor therapies to achieve the best outcomes for patients," said Bing Yao, Senior Vice President and Head of MedImmune's Respiratory, Inflammation and Autoimmunity Innovative Medicines Unit. "Respiratory disease is a core therapeutic area for AstraZeneca and we are encouraged by these results indicating benralizumab's potential to help certain groups of patients. We look forward to the further development of this promising new biologic as we progress our Phase III programmes in both COPD and severe asthma."