Purple Squirrel Economics, New York, NY, USA.
Purple Squirrel Economics, New York, NY, USA.
Clin Ther. 2020 May;42(5):860-872.e8. doi: 10.1016/j.clinthera.2020.02.020. Epub 2020 Mar 18.
Eltrombopag was evaluated as a second-line treatment for adult chronic immune thrombocytopenia (ITP) in the 2006 Phase III RAISE (Eltrombopag for Management of Chronic Immune Thrombocytopenia) randomized, placebo-controlled trial. More than 80% of patients reached satisfactory platelet counts within 2 weeks. However, the economic value of eltrombopag as a second-line treatment for ITP remains to be formally assessed. This study aimed to estimate the cost-effectiveness of treating ITP with a comparable thrombopoietin receptor agonist (eltrombopag vs romiplostim).
A Markov model was implemented over a lifetime time horizon to estimate the benefits and costs of each treatment. The model featured 3 health states based on current guidelines: (1) on treatment; (2) treatment failure/discontinuation; and (3) mortality. In line with therapeutic goals in ITP, model patients could experience 3 events: no bleeding, mild/moderate bleeding, or severe bleeding. Data on eltrombopag use were obtained from an open-label extension of previous Phase II/III trials, including RAISE. Romiplostim data were obtained from Phase III trials and an extension study. Lifetime overall survival was extrapolated by using treatment-specific mortality rates derived from severe bleeding and natural mortality rates. The costs of drugs, routine care, bleeding episodes, adverse events, and mortality were represented in the model.
Eltrombopag-treated patients gained 17.58 life years and 14.68 quality-adjusted life years, whereas romiplostim-treated patients gained 17.52 life years and 14.67 quality-adjusted life years. The total lifetime cost of eltrombopag treatment was estimated at $1.58 million versus $2.13 million for romiplostim. Sensitivity analyses supported base case findings. Deterministic sensitivity analysis predicted the greatest sensitivity to the rates of severe bleeding, discontinuation, and natural mortality. Probabilistic sensitivity analysis showed that eltrombopag would be an efficient use of resources at a $50,000 threshold in 52.8% of cases. In all probabilistic iterations, the total cost of eltrombopag treatment was lower than with romiplostim, primarily because of lower drug costs.
Clinical data were applied in an economic analysis, and eltrombopag exhibited economic dominance compared with romiplostim, driven largely by the reduced costs of primary therapy. This model was limited by a lack of specific patient-level data and robust data on the duration of secondary therapy, as well as by the fact that utilization values are likely conservative estimates for routine care use.
在 2006 年的三期 RAISE（依洛尤单抗治疗慢性免疫性血小板减少症）随机、安慰剂对照试验中，依洛尤单抗被评估为成人慢性免疫性血小板减少症（ITP）的二线治疗药物。超过 80%的患者在 2 周内达到了满意的血小板计数。然而，依洛尤单抗作为 ITP 的二线治疗药物的经济价值仍有待正式评估。本研究旨在评估比较性血小板生成素受体激动剂（依洛尤单抗与罗米司亭）治疗 ITP 的成本效益。
采用 Markov 模型在终生时间范围内估算每种治疗方法的效益和成本。该模型基于当前指南有 3 种健康状态：（1）治疗中；（2）治疗失败/停药；和（3）死亡。根据 ITP 的治疗目标，模型患者可能经历 3 种事件：无出血、轻度/中度出血或严重出血。依洛尤单抗使用数据来自先前的 II/III 期试验的开放标签扩展，包括 RAISE。罗米司亭数据来自 III 期试验和一项扩展研究。通过使用严重出血和自然死亡率得出的特定治疗死亡率来推断终生总生存情况。模型中表示了药物、常规护理、出血事件、不良事件和死亡率的成本。
依洛尤单抗治疗组患者获得了 17.58 个生命年和 14.68 个质量调整生命年，而罗米司亭治疗组患者获得了 17.52 个生命年和 14.67 个质量调整生命年。依洛尤单抗治疗的终生总成本估计为 158 万美元，而罗米司亭为 213 万美元。敏感性分析支持基本情况的发现。确定性敏感性分析预测对严重出血、停药和自然死亡率的变化最敏感。概率敏感性分析表明，在 52.8%的情况下，依洛尤单抗在 5 万美元的阈值下将是一种有效的资源利用。在所有概率迭代中，依洛尤单抗治疗的总成本均低于罗米司亭，主要原因是初级治疗的成本降低。
临床数据应用于经济分析中，依洛尤单抗与罗米司亭相比表现出经济性优势，主要原因是主要治疗的成本降低。该模型受到缺乏特定患者水平数据和二级治疗持续时间的稳健数据以及利用值可能是常规护理使用的保守估计的限制。
