The US FDA has approved mepolizumab (Nucala, GlaxoSmithKline) as an add-on maintenance treatment for adult patients with inadequately controlled COPD and an eosinophilic phenotype, according to a GSK news release.


RT’s Three Key Takeaways:

  1. New Biologic Option for COPD with Eosinophilic Phenotype: Mepolizumab is the first and only biologic approved for adults with inadequately controlled COPD and blood eosinophil counts ≥150 cells/µL.
  2. Proven Efficacy in Reducing Exacerbations: In the MATINEE and METREX phase III trials, mepolizumab significantly reduced moderate/severe exacerbation rates when added to inhaled triple therapy, addressing a key goal in COPD management.
  3. Potential to Lower Hospital Burden and Costs: Mepolizumab showed a trend toward fewer ED visits and hospitalizations, pointing to its potential to help mitigate the $7 billion annual US COPD hospitalization costs and improve patient outcomes.


The US FDA has approved mepolizumab (Nucala, GlaxoSmithKline) as an add-on maintenance treatment for adult patients with inadequately controlled COPD and an eosinophilic phenotype, according to a GSK news release.

FDA’s approval was based on data from the positive MATINEE and METREX phase III trials. Across these trials, mepolizumab showed a clinically meaningful and statistically significant reduction in the annualized rate of moderate/severe exacerbations versus placebo in a wide spectrum of COPD patients with an eosinophilic phenotype.1,2 Preventing exacerbations is a key goal of COPD management.3 Exacerbations are devastating for patients, known to cause irreversible lung damage, worsening of symptoms and increased mortality.3 The incidence of adverse events was similar between placebo and mepolizumab groups.1,2

Mepolizumab is the only approved biologic evaluated in patients with an eosinophilic phenotype characterized by a blood eosinophil count (BEC) threshold as low as ≥150 cells/µL.1,2 BEC is captured by a simple blood test that measures levels of eosinophils, a type of white blood cell which is a biomarker for type 2 inflammation and indicates a patient’s risk of exacerbation.3 Approximately 70% of COPD patients in the US who are inadequately controlled on inhaled triple therapy and continue to exacerbate have a BEC starting at 150 cells/μL and above.4,5 This represents over a million people at risk of exacerbations, including those leading to emergency department (ED) visits and/or hospitalizations, who could add mepolizumab as an option to their COPD treatment.4,5 

“The approval of Nucala in the US provides an important option for COPD patients,” said Kaivan Khavandi, SVP, Global Head, Respiratory, Immunology & Inflammation R&D, GSK. “Long-term follow-up studies have demonstrated that exacerbations are the single most important predictor of future risk, with particularly poor outcomes in those requiring hospital visits or admissions. Today there is hope for improved care for COPD patients with an eosinophilic phenotype, including those with a BEC threshold as low as ≥150cells/ÎĽL who need new options like Nucala to support their treatment journey.”

In both MATINEE and METREX trials, mepolizumab demonstrated a statistically significant reduction in the annualized rate of moderate or severe exacerbations compared with placebo, in patients with an eosinophilic phenotype, when added to triple inhaled therapy (MATINEE: rate ratio [RR], 0.79; 95% confidence interval [CI], 0.66 to 0.94; P=0.01) (METREX: rate ratio, 0.82; 95% CI, 0.68 to 0.98; adjusted P=0.04).1,2 

In a pre-defined secondary endpoint in MATINEE, the annualized rate of COPD exacerbations requiring ED visits and/or hospitalization was reduced in the mepolizumab group when compared with placebo (rate ratio [RR] of 0.65; 95% CI: 0.43, 0.96 [not statistically significant due to a failure of an endpoint higher in the pre-defined statistical testing hierarchy]). 1 COPD-related hospitalizations are a major healthcare challenge and are projected to become the number one cause of medical admissions.6 Emergency department visits and inpatient care already account for a large proportion of the annual direct medical costs of COPD, costing the US healthcare system around $7 billion a year.7

Jean Wright, MD, MBA, Chief Executive Officer of the COPD Foundation added: “COPD isn’t just a disease, it’s a relentless cycle. For individuals living with COPD, managing exacerbations is an ongoing challenge, even with inhaled maintenance therapy. Biologics like mepolizumab are providing renewed optimism for those affected by COPD.”

Mepolizumab is currently not approved for use in COPD in any other country. Regulatory submissions are under review in China and Europe.


References and notes

  1. Sciurba F, et al. Mepolizumab to prevent exacerbations in COPD with an eosinophilic phenotype. N Engl J Med. Apr 2025;392:1710-1720. Available at nejm.org.
  2. Pavord ID, et al. Mepolizumab for Eosinophilic Chronic Obstructive Pulmonary Disease. N Engl J Med. Oct 2017;377:1613-1629. DOI: 10.1056/NEJMoa1708208.
  3. Global Initiative for Chronic Obstructive Lung Disease (GOLD). 2025 Gold Report. Available at: goldcopd.org. Last accessed May 2025.
  4. GSK, Optum Analysis DOF (DOF 2024N562932_00).
  5. Müllerová H, et al. Exacerbations and health care resource use among patients with COPD in relation to blood eosinophil counts. Int J Chron Obstruct Pulmon Dis. 2019;14:683-692. DOI: 10.2147/COPD.S194367.
  6. Khakban A, et al. The Projected Epidemic of Chronic Obstructive Pulmonary Disease Hospitalizations over the Next 15 Years. A Population-based Perspective. Am J Respir Crit Care Med. 2017;195(3):287-291. DOI: 10.1164/rccm.201606-1162PP.
  7. American Lung Association (ALA). COPD Trends Brief – Burden. Available at: Lung.org. Last accessed: May 2025.
  8. Adeloye D, et al. Global, regional, and national prevalence of, and risk factors for, chronic obstructive pulmonary disease (COPD) in 2019: a systematic review and modelling analysis. Lancet Respir Med. 2022;10(5):447-458. DOI: 10.1016/S2213-2600(21)00511-7.
  9. Chen S, et al. The global economic burden of chronic obstructive pulmonary disease for 204 countries and territories in 2020-50: a health-augmented macroeconomic modelling study. Lancet Glob Health. 2023;11(8):e1183-e1193. DOI: 10.1016/S2214-109X(23)00217-6.
  10. Chen S, Miravitlles M, Rhee CK, et al. Patients with Chronic Obstructive Pulmonary Disease and Evidence of Eosinophilic Inflammation Experience Exacerbations Despite Receiving Maximal Inhaled Maintenance Therapy. Int J Chron Obstruct Pulmon Dis. 2022 Sep 9;17:2187–2200. DOI: 10.2147/COPD.S378649.