GSK presents data on of Nucala in asthma patients stratified by eosinophil levels

Data from a post-hoc study show that severe asthma patients with a baseline blood eosinophil count of 150 cells/μL or above who received GSK’s Nucala (100mg fixed dose subcutaneous injection of mepolizumab) or an investigational dose of mepolizumab had a significant improvement in their exacerbation rates compared to those receiving placebo.

The data showed that when these patients were stratified by baseline eosinophil levels, a significant improvement in exacerbation rates was observed in all groups receiving mepolizumab with the greatest improvement occurring in those patients with higher levels of eosinophils.

These results are from a meta-analysis of data generated in 1192 patients, 846 who received mepolizumab and 346 on placebo, from the DREAM  and MENSA studies. Overall, the meta-analysis demonstrated a 47% reduction in annual exacerbation rates with mepolizumab versus placebo. Clinically relevant reductions in exacerbation rate were shown to range from 52% for patients with a baseline eosinophil threshold of 150 cells/μL or above, to 70% for patients with a baseline eosinophil threshold of 500 cells/μL or above.

Eosinophils as a biomarker

Commenting on the data, Steve Yancey, Medicines Development Lead for mepolizumab, GSK said: “In a sub-set of asthma patients eosinophils drive airway inflammation. By utilising eosinophils as a biomarker, we have been able to identify those asthma patients whose disease is severe and driven by the over-expression of eosinophils and are therefore likely to respond to treatment. This post-hoc analysis confirms the predictive nature of the relationship between baseline blood eosinophil counts and efficacy outcomes in patients treated with mepolizumab.”

Eosinophils are a type of white blood cell that play a role in the development of asthma. In people with asthma, inflammatory mediators released from the eosinophil cause inflammation in the lungs increasing the risk of an exacerbation. By measuring blood eosinophil levels (a biomarker for inflammation) using a routine complete blood count, and reviewing a patient’s history of exacerbations along with their current medications, doctors are able to identify the patients who are most likely to benefit from treatment with mepolizumab. GSK says the results of the meta-analysis reinforce the relevance of a data-driven approach to determining the eosinophil cut-off levels used to identify the patient population that is appropriate for treatment with mepolizumab.