RESUMEN
INTRODUCTION: The Nucala Effectiveness Study (NEST) assessed the effectiveness of mepolizumab in patients with severe asthma (SA) in countries previously underrepresented in real-world studies. METHODS: A multi-country, bi-directional, self-controlled, observational cohort study conducted in Colombia, Chile, India, Türkiye, Saudi Arabia, United Arab Emirates, Kuwait, Oman, and Qatar. Historical and/or prospective data from patients with SA were assessed 12 months pre- and post-mepolizumab initiation. PRIMARY ENDPOINT: incident rate ratio (IRR) of clinically significant exacerbations (CSEs). Key secondary endpoints: healthcare resource utilisation (HCRU), oral corticosteroid (OCS) use, lung function and symptom control (Asthma Control Test [ACT] scores). RESULTS: Overall, 525 patients with SA burden pre-initiation (geometric mean blood eosinophil count [BEC] 490.7 cells/µl; 31.4% prior biologic use; 37.3% obese) received at least one dose of mepolizumab 100 mg subcutaneously. Post-initiation, a significant reduction in CSEs was observed (76% [p < 0.001]; IRR [95% confidence interval] 0.24 [0.19-0.30]); 72.0% of patients had no CSEs. Mepolizumab treatment led to a reduction in OCS use (52.8% pre-initiation vs. 16.6% post-initiation) and a mean (standard deviation [SD]) change in OCS dose of - 18.1 (20.7) mg post-initiation; 36.1% of patients became OCS-free. Fewer patients were hospitalised post-initiation (22.5% pre-initiation vs. 6.9% post-initiation). Improvements in mean (SD) forced expiratory volume in 1 s (62.8 [20.2]% pre-initiation vs. 73.0 [22.7]% post-initiation) and ACT scores (15.0% pre-initiation vs. 64.5% of patients post-initiation with well-controlled asthma) were observed. Proportion of patients with BEC ≥ 500 cells/µl decreased from 84.4% pre-initiation to 18.1% post-initiation. CONCLUSION: Mepolizumab was effective in reducing the burden of SA by significantly reducing CSEs, reducing OCS use and HCRU, and improving lung function and asthma control, which could translate to improvements in health-related quality of life in patients with SA and high OCS dependency in the countries studied. A graphical abstract is available with this article.
Severe asthma occurs when asthma symptoms remain uncontrolled despite optimised treatment. In many low-middle income countries, and in some countries in the Middle East, Asia, Latin America and the Arab Gulf, the management and treatment of patients with severe asthma remain poor, with many patients having unscheduled hospital visits or admission, and use of steroids for a prolonged period. Mepolizumab is an injectable monoclonal antibody approved as an add-on treatment for severe asthma in patients ≥ 6 years of age. In clinical trials, mepolizumab has demonstrated reductions in the risk of clinically significant exacerbations (CSE; an asthma exacerbation that requires systemic corticosteroids and/or an emergency room visit and/or hospitalisation) and the need for oral corticosteroid (OCS) treatment in patients with severe asthma by reducing inflammation caused by eosinophil (a type of white blood cell) production. The Nucala Effectiveness Study (NEST) was performed to observe the effectiveness of mepolizumab in people with severe asthma in Colombia, Chile, India, Turkey, Saudi Arabia, United Arab Emirates, Kuwait, Oman and Qatar. The frequency of CSEs and other outcomes was compared 12 months pre- and post-mepolizumab initiation. Post-initiation, the risk of CSEs was significantly reduced by 76% (p < 0.001), and 72% of patients had no CSEs. Fewer patients were dependent on OCS, with 36.1% of patients not using OCS at all, and fewer patients were hospitalised. Lung function and asthma control also improved. NEST shows that mepolizumab could benefit people with severe asthma living in countries where disease-related burden and OCS use remain high.