Dewilde S, Turk F, Tambour M, Sandström T
United BioSource Corporation, Belgium.
Curr Med Res Opin. 2006 Sep;22(9):1765-76. doi: 10.1185/030079906X132389.
Severe allergic asthma patients may not be controlled even with guideline recommended care, including inhaled corticosteroids, long-acting beta-2 agonists, theophylline, oral steroids and anti-leukotrienes. They experience exacerbations requiring intensive healthcare use and which may be fatal. Omalizumab, a new monoclonal antibody for use in IgE-mediated allergic diseases, reduces exacerbations and daily symptoms in this patient population. The aim of this study is to estimate the cost effectiveness of adding omalizumab to optimized standard therapy (ST) in patients with severe persistent IgE-mediated (allergic) asthma.
A Markov model comparing lifelong ST with a treatment period of omalizumab add-on therapy followed by ST, was developed based on efficacy data from the INNOVATE trial (28 weeks, N = 419) and Swedish life table and cost data. This model assumes that patients are at risk of having an exacerbation every 2 weeks and are at risk of dying from a clinically significant severe asthma exacerbation. Patients in a steady-state of having no exacerbations are defined to be in an 'optimized asthma control' state. Resource use data and utilities were obtained from INNOVATE and from a UK observational study. Costs from a societal perspective include estimates for drugs, routine care, exacerbations and costs in added years of life; benefits are expressed in QALYs. The response to omalizumab was evaluated after 16 weeks of trial, and non-responders stopped taking omalizumab for the remaining time.
Total lifetime discounted costs and QALYs on ST were 52,702 euros and 11.60. Omalizumab add-on therapy cost an additional 42,754 euros for 0.76 additional QALYs, resulting in an incremental cost-effectiveness ratio of 56,091 euros. A probabilistic sensitivity analysis indicates that the 95% CI around the ICER is [31,328 euros; 120,552 euros]. One-way analyses indicate that the results are sensitive to the exacerbation-related mortality rate, the time horizon and the discount rates.
Based on the model and the assumptions used, our results suggest that omalizumab provides cost offsets, improves quality of life and may have an attractive ICER in treating the severe allergic asthma population.
即使采用指南推荐的治疗方法，包括吸入性糖皮质激素、长效β2受体激动剂、茶碱、口服类固醇和抗白三烯药物，重度过敏性哮喘患者的病情仍可能无法得到控制。他们会经历病情加重，需要大量医疗护理，甚至可能致命。奥马珠单抗是一种用于治疗IgE介导的过敏性疾病的新型单克隆抗体，可减少该患者群体的病情加重和日常症状。本研究的目的是评估在重度持续性IgE介导（过敏性）哮喘患者中，在优化标准治疗（ST）基础上加用奥马珠单抗的成本效益。
基于INNOVATE试验（28周，N = 419）的疗效数据、瑞典生命表和成本数据，建立了一个马尔可夫模型，比较终身ST与奥马珠单抗附加治疗一段时间后再进行ST的情况。该模型假设患者每2周有病情加重的风险，并有因临床上显著的重度哮喘加重而死亡的风险。处于无病情加重稳定状态的患者被定义为处于“优化哮喘控制”状态。资源使用数据和效用值来自INNOVATE试验和一项英国观察性研究。从社会角度计算的成本包括药物、常规护理、病情加重及延长生命年份的成本估计；效益以质量调整生命年（QALY）表示。在试验16周后评估对奥马珠单抗的反应，无反应者在剩余时间停止服用奥马珠单抗。
终身ST的总贴现成本和QALY分别为52,702欧元和11.60。奥马珠单抗附加治疗额外花费42,754欧元，增加0.76个QALY，增量成本效益比为56,091欧元。概率敏感性分析表明，增量成本效益比的95%置信区间为[31,328欧元；120,552欧元]。单因素分析表明，结果对病情加重相关死亡率、时间范围和贴现率敏感。
基于所使用的模型和假设，我们的结果表明，奥马珠单抗可抵消成本、改善生活质量，在治疗重度过敏性哮喘人群方面可能具有有吸引力的增量成本效益比。
