China: Researchers have found in a new meta-analysis that mepolizumab is an effective and safe treatment for severe eosinophilic asthma, leading to improved lung function, fewer exacerbations, and better asthma control.A dosing range of 75–100 mg offers a favorable benefit–to–risk profile. Baseline blood eosinophil count emerges as a useful predictive biomarker for treatment response, supporting personalized therapy. Further studies are needed to define optimal dosing strategies and assess long-term safety.The findings, published in the Journal of Thoracic Disease, come from a systematic review and meta-analysis led by Yubing Li from the Department of Respiratory and Critical Care Medicine, Jianli People’s Hospital, China Three Gorges University, and colleagues. Severe eosinophilic asthma, a subtype characterized by persistent type 2 inflammation and high interleukin-5 (IL-5)–mediated eosinophil activity, accounts for over half of all asthma cases and often remains uncontrolled despite high-dose corticosteroid therapy.Mepolizumab, an anti–IL-5 monoclonal antibody, offers a targeted approach, but previous studies have shown inconsistent results regarding improvements in lung function and long-term outcomes.To address these uncertainties, the researchers systematically analyzed randomized controlled trials assessing mepolizumab in patients aged 12 years or older with baseline blood eosinophils of at least 150 cells/µL. Ten trials involving 4,471 patients were included. Key outcomes measured were lung function, using forced expiratory volume in 1 second (FEV1), asthma exacerbation rates, and symptom control via the Asthma Control Questionnaire-5 (ACQ-5), along with safety assessments. Subgroup analyses explored the impact of baseline eosinophil counts and dosing regimens on efficacy and safety. The meta-analysis revealed the following findings:Mepolizumab significantly improved lung function, with a mean FEV1 increase of 0.06 L compared to placebo.Exacerbation rates were reduced by 42% in patients receiving mepolizumab.Asthma control improved, with ACQ-5 scores decreasing by 0.29 points.Low-dose mepolizumab (75–100 mg) provided greater improvements in FEV1 and exacerbation reduction than higher doses.The 75–100 mg regimen reduced the risk of serious adverse events by 61% compared with higher-dose treatments.Patients with baseline eosinophil counts ≤300 cells/µL showed a better response to mepolizumab, supporting biomarker-guided, individualized therapy.The analysis confirms that mepolizumab is both effective and well-tolerated, supporting its use as a targeted biologic therapy in severe eosinophilic asthma. Importantly, the study resolves previous uncertainties regarding lung function benefits and establishes that low-dose regimens offer the optimal balance of efficacy and safety. The findings also reinforce the value of baseline blood eosinophil levels as a predictive biomarker to guide clinical decision-making.The authors recommend adopting low-dose mepolizumab (75–100 mg) as a first-line biologic for severe eosinophilic asthma, with treatment decisions guided by blood eosinophil counts. They emphasize the need for further large-scale studies with long-term follow-up to determine optimal dosing intervals and assess extended safety profiles, aiming to refine personalized treatment approaches for this challenging patient population.Reference:Li Y, Li J, Yang H, Wu L. Efficacy and safety of mepolizumab in severe eosinophilic asthma: a systematic review and meta-analysis. J Thorac Dis 2025;17(11):9425-9438. doi: 10.21037/jtd-2025-1596