Lessing Charon, Ashton Toni, Davis Peter
Health Systems Section, School of Population Health, University of Auckland, Private Bag 92019, Auckland, New Zealand,
Appl Health Econ Health Policy. 2014 Oct;12(5):537-46. doi: 10.1007/s40258-014-0110-0.
Many countries have implemented generic reference pricing and substitution as methods of containing pharmaceutical expenditure. However, resistance to switching between medicines is apparent, especially in the case of anti-epileptic medicines.
This study sought to exploit a nation-wide policy intervention on generic reference pricing in New Zealand to evaluate the health outcomes of patients switching from originator to generic lamotrigine, an anti-epileptic medicine.
A retrospective study using the national health collections and prescription records was conducted comparing patients who switched from originator brand to generic lamotrigine with patients who remained on the originator brand. Primary outcome measures included switch behaviour, changes in utilisation of healthcare services at emergency departments, hospitalisations and use of specialist services, and mortality.
Approximately one-quarter of all patients using the originator brand of lamotrigine switched to generic lamotrigine, half of whom made the switch within 60 days of the policy implementation. Multiple switches (three or more) between generic and brand products were evident for around 10% of switchers. Switch-back rates of 3% were apparent within 30 days post-switch. No difference in heath outcome measures was associated with switching from originator lamotrigine to a generic equivalent and hence no increased costs could be found for switchers.
Switching from brand to generic lamotrigine is largely devoid of adverse health outcomes; however, creating an incentive to ensure a greater proportion of patients switch to generic lamotrigine is required to achieve maximal financial savings from a policy of generic reference pricing.
许多国家已实施仿制药参考定价和替换作为控制药品支出的方法。然而，药品之间的换药阻力明显，尤其是在抗癫痫药物的情况下。
本研究旨在利用新西兰一项针对仿制药参考定价的全国性政策干预措施，评估从原研拉莫三嗪（一种抗癫痫药物）转换为仿制药的患者的健康结局。
利用国家卫生数据集和处方记录进行一项回顾性研究，比较从原研品牌转换为仿制药拉莫三嗪的患者与继续使用原研品牌的患者。主要结局指标包括换药行为、急诊科医疗服务利用情况的变化、住院情况、专科服务使用情况以及死亡率。
所有使用原研品牌拉莫三嗪的患者中约四分之一转换为仿制药拉莫三嗪，其中一半在政策实施后60天内完成转换。约10%的换药者在仿制药和品牌产品之间出现多次换药（三次或更多次）。换药后30天内的换回率为3%。从原研拉莫三嗪转换为仿制药等效产品与健康结局指标无差异，因此换药者未发现成本增加。
从品牌拉莫三嗪转换为仿制药在很大程度上没有不良健康结局；然而，需要建立激励机制以确保更大比例的患者转换为仿制药拉莫三嗪，才能从仿制药参考定价政策中实现最大程度的财务节省。
