Mepolizumab

Nucala is the only approved biologic showing efficacy for up to two years in a wide spectrum of COPD patients with raised blood eosinophils inadequately controlled by the combination of an ICS/LABA/LAMA. Approval is based on MATINEE, METREX and METREO Phase III trials. MATINEE data showed a reduction in moderate/severe exacerbations, including those leading to hospitalization and/or emergency department visits. As of 2025, COPD and/or bronchitis remains the most common cause of unplanned hospitalization in Canada. MISSISSAUGA, ON , June 2, 2026 /CNW/ - GSK announced today that Health Canada has approved Nucala (mepolizumab) as an add-on maintenance treatment in adult patients with COPD characterized by raised blood eosinophils inadequately controlled by the combination of an inhaled corticosteroid (ICS), a long-acting beta2-agonist (LABA) and a long-acting muscarinic antagonist (LAMA). Health Canada's approval was based on data from the MATINEE, METREX and METREO Phase III trials. In MATINEE and METREX, Nucala showed a statistically significant reduction in the annualized rate of moderate/severe exacerbations versus placebo in a COPD patient population with raised blood eosinophils (MATINEE: rate ratio [RR], 0.79; 95% confidence interval [CI], 0.66 to 0.94) (METREX: rate ratio, 0.82; 95% CI, 0.68 to 0.98). 1 , 2 In METREO, Nucala demonstrated a numerical reduction in moderate/severe exacerbations compared to placebo, consistent with what was shown in METREX and MATINEE, although not statistically significant after adjusting for multiplicity. This was in addition to inhaled triple therapy (a combination of inhaled corticosteroid, long-acting beta agonist and long-acting antimuscarinic antagonist). In a pre-defined secondary endpoint in MATINEE, the annualized rate of COPD exacerbations requiring emergency department visits and/or hospitalization was numerically reduced in the Nucala group compared with placebo but did not meet statistical significance (rate ratio [RR] of 0.65; 95% CI: 0.43, 0.96). 1 Preventing exacerbations is a key goal of COPD management. 3 ,6 Exacerbations, especially those that lead to emergency department (ED) visits or hospitalizations, are devastating for patients and are known to cause irreversible lung damage, worsening of symptoms and increased mortality. 3 COPD remains a major healthcare challenge in Canada, ranking consistently as the most common cause of unplanned hospitalization in Canada, along with bronchitis. 4 Nucala is the only approved biologic whose efficacy at reducing hospitalization and ED visits was evaluated as a pre-defined secondary endpoint. 1 , 2 "At GSK Canada, we understand the daily challenges faced by COPD patients and the heavy toll that exacerbations can take on their lives," says Dr. Michelle Horn, Country Medical Director, GSK Canada . "The approval of Nucala for COPD is about bringing hope and tangible relief–particularly for those patients with raised eosinophils. We are committed to providing innovative solutions like Nucala that can help these patients reduce flareups, remain out of hospital and live more fulfilling lives." Nucala is the only approved biologic for COPD that has been evaluated in patients with moderate to very severe airflow limitation, with or without chronic bronchitis, and 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 the level of eosinophils, a type of white blood cell that is a biomarker for inflammation and indicates a patient's elevated risk of exacerbation. 3 "For too long, the approach to respiratory care has been one-size-fits-all," notes Henry Roberts, Managing Director of COPD Canada . "The development of personalized treatments, like biologics, gives us hope that patients can finally receive care tailored to their unique needs." About MATINEE, METREX and METREO MATINEE, METREX and METREO are Phase III, randomized, double-blind, parallel-group trials assessing the efficacy and safety of Nucala as an add-on therapy when administered subcutaneously every four weeks versus placebo in addition to optimal inhaled triple therapy (dual long-acting bronchodilators plus inhaled corticosteroid). 1 , 2 MATINEE assessed the efficacy and safety of Nucala 100 mg for 52–104 weeks in 804 patients with COPD with a blood eosinophil count ≥300 cells/µl at screening and ≥150 cells/µL in the 12 months prior. 1 Patients could participate with a range of clinical presentations of COPD including chronic bronchitis, emphysema only or a combination of both. 1 The severity of patients' airflow obstruction ranged from moderate to very severe, or stages 2–4 as assessed by the medically recognized Global Initiative for Chronic Obstructive Lung Disease (GOLD) scale. 3 The full analysis of MATINEE included 403 patients enrolled on the Nucala arm and 401 on placebo, all of whom had experienced at least two moderate or one severe exacerbation in the previous year despite receiving optimized inhaled maintenance therapy. 1 Full MATINEE study results were published in the New England Journal of Medicine 1 with further data presented at the 2025 and 2026 American Thoracic Society International Congress, including investigating disease stability as an outcome and examining the outcomes in patients with varying severities of airflow obstruction and those with chronic bronchitis only, emphysema only or both. 1,5,6,7 In METREX, the efficacy and safety of Nucala 100 mg was evaluated for 52 weeks in 836 patients randomized (1:1) to Nucala or placebo across two groups: an eosinophilic phenotype group (blood eosinophil count of ≥150 cells/µl at study entry or ≥ 300 cells/µl within the past year) and a non-eosinophilic phenotype group (blood eosinophil count of <150 cells/µl at study entry and no evidence of ≥300 cells/µl within the past year). 2 In METREO, the efficacy and safety of Nucala (100 and 300 mg) was evaluated for 52 weeks in 674 patients with an eosinophilic phenotype (blood eosinophil count of ≥150 cells/µl at study entry or ≥300 cells/µl within the past year) randomized (1:1:1) to Nucala 100 mg, Nucala 300 mg or placebo. 2 The study results from METREO and METREX were published in 2017 in the New England Journal of Medicine . 2 About COPD COPD is a progressive and heterogeneous inflammatory lung disease that includes chronic bronchitis and/or emphysema. 3 It affects more than two million Canadians, 26% of them over 85. 8 Patients with COPD experience persistent respiratory symptoms that impact daily life such as breathlessness, cough and sputum along with progressive airflow obstruction due to chronic inflammation. 3,9 Despite inhaled triple therapy, many patients experience persistent symptoms and exacerbations. 10 Exacerbations are acute episodes of worsening COPD symptoms that can result in hospitalization and irreversible lung damage.3 Early intervention is important in preventing exacerbations and cumulative lung damage. 3 About Nucala Nucala is a monoclonal antibody that targets and binds to interleukin-5 (IL-5), one of the messenger proteins (cytokines) involved in eosinophilic inflammation. Nucala is currently approved for use in Canada across four other IL-5 mediated conditions. Please consult the Product Monograph at for complete safety information. The Product Monograph is also available by calling 1-800-387-7374. About GSK in Respiratory GSK continues to build on decades of pioneering work to deliver more ambitious treatment goals, develop the next-generation standard of care and redefine the future of respiratory medicine for hundreds of millions of people with respiratory diseases. With an industry-leading respiratory portfolio and pipeline of vaccines, targeted biologics and inhaled medicines, we are focused on improving outcomes and the lives of people living with all types of asthma and COPD along with less-understood refractory chronic cough or rarer conditions like systemic sclerosis with interstitial lung disease. GSK is harnessing the latest science and technology with the aim of modifying the underlying disease dysfunction and preventing progression. About GSK GSK is a global biopharma company with a purpose to unite science, technology and talent to get ahead of disease together. Find out more at . Cautionary statement regarding forward-looking statements GSK cautions investors that any forward-looking statements or projections made by GSK, including those made in this announcement, are subject to risks and uncertainties that may cause actual results to differ materially from those projected. Such factors include, but are not limited to, those described in the "Risk Factors" section in GSK's Annual Report on Form 20-F for 2025, and GSK's Q1 Results for 2026. References ___________________________ 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 : . Last accessed May 2025 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 5 Han MK, et al. Presented at ATS, May 16–21, 2025, San Francisco, CA. Poster P1017. 6 Pavord ID, et al. Presented at ATS, May 16–21, 2025, San Francisco, CA. Poster P1012. 7 Singh D, et al. Presented at ATS, May 15-20, 2026, Orlando, FL. Poster P1506. 8 What is COPD? | Canadian Lung Association 9 2023-CTS-COPD-Pharmacotherapy-Guideline-1.pdf 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. SOURCE GlaxoSmithKline Inc.