GlaxoSmithKline plc (GSK) presented new data from the longest study of an anti-IL5 biologic treatment in severe eosinophilic asthma to be reported. The study showed consistent reductions in exacerbations and improvements in asthma control, with a safety profile similar to previous clinical studies, in severe eosinophilic asthma patients treated with Nucala (mepolizumab) over the long-term study period. One third of patients in the study treated with mepolizumab experienced no exacerbations, despite entering the study with an average of almost two exacerbation (1.74) per year.

The open-label COLUMBA study, presented at the American Thoracic Society (ATS) conference, is a long-term safety and efficacy study of mepolizumab in patients with severe eosinophilic asthma. The study reports data from patients who were on mepolizumab treatment for an average of 3.5 years and a maximum of 4.5 years.

Results showed: 61% decrease in exacerbation rate (from 1.74 events/year at enrolment to 0.68 events/year during the treatment period, 95% confidence interval 0.60, 0.78); Consistent exacerbation rates per year over the study period (year one, 0.71, year two, 0.82, year three, 0.71); Improvement in asthma control (improved (ACQ5) by -0.47) from first assessment (Week 12) and maintained for over four years; 8% reduction in blood eosinophils (white blood cells that cause inflammation in certain people with severe asthma), by week 4, sustained until the end of the study; Safety and immunogenicity profiles of long-term Nucala treatment observed in the COLUMBA study similar to that seen in prior severe asthma studies; Initial improvements in lung function (mean pre-bronchodilator FEV1) gradually decreased over the study period, reflecting the general decline in lung function expected in this patient population.

Dave Allen Head, Respiratory Therapy Area R&D, GSK said: “These new data give us evidence that Nucala, a targeted biologic treatment, provides an enduring benefit to patients with severe eosinophilic asthma. The findings show the sustained exacerbation reduction and asthma control delivered by this medicine over a substantial length of time, with no new safety findings.”

Sumita Khatri, Associate Professor of Medicine at Cleveland Clinic, Ohio and Principal Investigator in the COLUMBA study said: “People with severe eosinophilic asthma for whom control has not been possible with inhaled or oral therapy have always sought options to improve control. We know this may be achieved with biologic therapy and are excited to see the long-term effectiveness of the anti-IL-5 therapy, Nucala, balanced with a long-term safety profile.”

COLUMBA was a long-term, open-label extension study, which investigated the efficacy and safety of mepolizumab in patients with severe eosinophilic asthma who participated in the 12-month DREAM study. In the COLUMBA study 347 patients, who had been out of the DREAM study for at least 12 months, received 100 mg subcutaneous mepolizumab every 4 weeks in addition to standard care for an average of 3.5 years

Due to the long-term nature of the study and natural attrition of subjects in studies of this duration, there were fewer patients in the later stages of the study than in the first two to three years.

Nucala (mepolizumab) is the first-in-class biologic treatment for patients with severe eosinophilic asthma. It is approved in over 40 countries including the EU, US, and Japan and has been prescribed to over 18,000 patients in the US It has been studied in over 3,000 patients in 16 clinical trials across a number of eosinophilic conditions. Nucala (300mg) was recently approved in the US for the treatment of adult patients with a rare disease called eosinophilic granulomatosis with polyangiitis (EGPA). A sBLA has also been filed for the treatment in patients with chronic obstructive pulmonary disease and is currently being investigated for severe hypereosinophilic syndrome and nasal polyposis.

When inflammation occurs in the lungs it can affect the airways, making breathing difficult and increasing the frequency of exacerbations or asthma attacks. Although the mechanism of action has not been definitively established, Nucala is believed to work by preventing the ‘IL-5’ cytokine from binding to its receptor on the surface of the eosinophil cells, which in turn reduces eosinophil levels.

Severe eosinophilic asthma is driven by inflammation linked to higher-than-normal eosinophils (a type of white blood cell) being present in the blood. When present in the body in normal levels, eosinophils can play a role in protecting the body against infection but over-production can cause inflammation in vital organs and tissues, sometimes permanently damaging them.

In the US, Nucala (100mg fixed dose subcutaneous injection of mepolizumab) is licensed as an add-on maintenance treatment for patients with severe asthma aged 12 years and older, and with an eosinophilic phenotype. Nucala (3x 100mg subcutaneous injection of mepolizumab) is licensed for the treatment of adult patients with eosinophilic granulomatosis with polyangiitis (EGPA). Nucala is not approved for the relief of acute broncho spasm or status asthmaticus. Full US Prescribing Information is available at US Prescribing Information Nucala.