Department of Industrial and Systems Engineering, University of Minnesota College of Science and Engineering, Minneapolis, MN.
Division of Health Policy and Management, University of Minnesota School of Public Health, Minneapolis, MN.
Inflamm Bowel Dis. 2020 Jan 1;26(1):103-111. doi: 10.1093/ibd/izz113.
Therapeutic drug monitoring (TDM) is increasingly performed for Infliximab (IFX) in patients with Crohn's disease (CD). Reactive TDM is a cost-effective strategy to empiric IFX dose escalation. The cost-effectiveness of proactive TDM is unknown. The aim of this study is to assess the cost-effectiveness of proactive vs reactive TDM in a simulated population of CD patients on IFX.
We developed a stochastic simulation model of CD patients on IFX and evaluated the expected health costs and outcomes of a proactive TDM strategy compared with a reactive strategy. The proactive strategy measured IFX concentration and antibody status every 6 months, or at the time of a flare, and dosed IFX to a therapeutic window. The reactive strategy only did so at the time of a flare.
The proactive strategy led to fewer flares than the reactive strategy. More patients stayed on IFX in the proactive vs reactive strategy (63.4% vs 58.8% at year 5). From a health sector perspective, a proactive strategy was marginally cost-effective compared with a reactive strategy (incremental cost-effectiveness ratio of $146,494 per quality-adjusted life year), assuming a 40% of the wholesale price of IFX. The results were most sensitive to risk of flaring with a low IFX concentration and the cost of IFX.
Assuming 40% of the average wholesale acquisition cost of biologic therapies, proactive TDM for IFX is marginally cost-effective compared with a reactive TDM strategy. As the cost of infliximab decreases, a proactive monitoring strategy is more cost-effective.
越来越多的克罗恩病（CD）患者接受英夫利昔单抗（IFX）的治疗药物监测（TDM）。反应性 TDM 是经验性 IFX 剂量升级的一种具有成本效益的策略。主动 TDM 的成本效益尚不清楚。本研究旨在评估主动 TDM 与反应性 TDM 在接受 IFX 治疗的 CD 患者模拟人群中的成本效益。
我们开发了一个接受 IFX 治疗的 CD 患者的随机模拟模型，并评估了主动 TDM 策略与反应性策略相比的预期健康成本和结果。主动策略每 6 个月测量一次 IFX 浓度和抗体状态，或在疾病发作时进行，将 IFX 剂量调整至治疗窗。反应性策略仅在疾病发作时进行。
主动策略导致的疾病发作少于反应性策略。与反应性策略相比，更多的患者在主动策略中继续使用 IFX（第 5 年时分别为 63.4%和 58.8%）。从卫生部门的角度来看，与反应性策略相比，主动策略具有边际成本效益（每增加一个质量调整生命年的增量成本效益比为 146494 美元），假设 IFX 的批发价格为 40%。结果对低 IFX 浓度和 IFX 成本的疾病发作风险最为敏感。
假设生物治疗药物的平均批发采购成本的 40%，与反应性 TDM 策略相比，主动 TDM 对 IFX 具有边际成本效益。随着英夫利昔单抗价格的降低，主动监测策略的成本效益更高。
