孤儿药经济学评估中的支付阈值探讨

Discussion on the payment threshold in the economical evaluation of orphan drugs

目的:调整孤儿药经济性评价中支付阈值的设定方法,提升其经济性评价的合理性。方法:深入分析经济性评价支付阈值设定的理论基础,从健康效用理论角度探讨支付阈值设定理论的不足,探讨孤儿药阈值调整的理论方案,并通过文献研究和国际经验总结进行验证。结果:传统的成本—效用分析默认每单位质量调整生命年(Quality-Adjusted Life Years,QALYs)对应的健康效用恒定,低估了能大幅改善重症罕见病患者健康的孤儿药的价值。理论分析表明,对于初始QALY几乎为零的重症罕见病患者,随着健康的改善,每获得一单位QALY对应的边际健康效用递增,直到患者能正常参与各种社会活动,之后边际健康效用递减。基于按效用付费的原则,如果孤儿药可大幅改善重症罕见病患者的健康,孤儿药的支付阈值应高于只能轻微改善健康的一般药品。结论:应根据QALYs改善程度调整传统的恒定阈值,以科学评价孤儿药的经济性。

Objectives:To adjust the payment threshold setting method in the economical evaluation of orphan drugs,so as to improve the rationality of their economical evaluation.Methods:This article conducted in-depth analysis on the theoretical basis setting the payment threshold in the economical evaluation,discussed the theoretical shortcoming of payment threshold setting from the perspective of health utility theory,and explored the theoretical solution of adjusting the payment threshold for orphan drugs.Literature review and international experience summarization were then conducted for verification.Results:The conventional cost-utility analysis assumes that health utility corresponding to one unit of QALY is a constant,therefore underestimating the value of orphan drugs which can greatly improve the health condition of patients with severe rare diseases.Based on our theoretical analysis,for patients with severe rare diseases that have an initial QALY of almost zero,during the improvement of their health condition,their marginal health utility while gaining every addition unit of QALY will monotonically increase until the patients can participate in social activities in a normal manner,after which the marginal health utility will start to decrease.Based on the principle of paying by utility,if orphan drugs can greatly improve the health condition of patients with severe rare diseases,the payment threshold of orphan drugs should be higher that of general drugs which can only slightly improve the health condition of patients.Conclusions:The traditional constant threshold mechanism should be adjusted according to QALYs,which would allow a more scientific evaluation of the economic efficiency of orphan drugs.