Mepolizumab (Nucala) Is A New Treatment to Reduce Flare-ups of COPD
Background: Pharmaceutical companies perform research to find new treatments for those with COPD. Based on results of studies in asthma, there is interest in targeting the eosinophil – a type of white blood cell that is a normal part of the body’s immune system. However, too many eosinophils may lead to inflammation in the lungs that can cause asthma and COPD breathing attacks.
Up to 40% of patients with COPD have elevated levels of eosinophils in the blood. It appears that high levels of eosinophils are associated with an increased risk of COPD flare-ups (exacerbations). Inhaled corticosteroids can reduce flare-ups and are frequently prescribed along with one or two bronchodilators to reduce possible flare-ups. This is called triple therapy (see posts on September 21, 2017, and August 17, 2017).
Mepolizumab (brand name: Nucala) is a “humanized monoclonal antibody” made in hampster ovary cells that blocks interleukin-5, which regulates eosinophils.
A microscopic view of a blood smear shows an eosinophil (an inflammatory cell) in the center surrounded by smaller red blood cells.
Diagram of how mepolizumab blocks interleukin-5 to reduce eosinophils – an inflammatory cell
Study: Dr. Pavord and colleagues reported on two studies evaluating mepolizumab (Nucala) compared with placebo (inactive) in those with COPD who had two or more flare-ups or at least one leading to hospitalization in the past year. These flare-ups occurred even though all subjects were taking inhaled “triple therapy.” Mepolizumab or placebo was given by subcutaneous shot (injection) every 4 weeks over one year. The results were compared in those with normal and with high levels of eosinophils in the blood.
The study was sponsored by the pharmaceutical company – GlaxoSmithKline. The findings were published in the September 12, 2017, issue of the New England Journal of Medicine (volume 377; pages 1613-1624).
Results: Overall, mepolizumab (100 mg dose injected every 4 weeks) was associated with a lower rate of flare-ups requiring an antibiotic and/or prednisone than placebo in patients with COPD who had high levels of blood eosinophils.
Conclusion: The authors concluded that eosinophilic inflammation in the breathing tubes (airways) contribute to flare-ups (exacerbations) of COPD and that blocking interleukin-5 with mepolizumab (Nucala) reduces both blood eosinophils and flare-ups over one year.
My Comments: Mepolizumab (Nucala) was approved by the US FDA (November 4, 2015) for the treatment of those with severe asthma who have high eosinophil counts in the blood.
If this monoclonal antibody receives future approval by the FDA for COPD, it will offer a new option as add-on therapy for those with COPD on “triple therapy ” who continue to have frequent flare-ups.
Dr. Ian Pavord, Professor of Respiratory Medicine at the University of Oxford