标题： 格列卫在参加医疗保险D部分的慢性髓性白血病患者中的价格弹性：基于回归不连续设计的证据 显示英文标题

标题： The price elasticity of Gleevec in patients with Chronic Myeloid Leukemia enrolled in Medicare Part D: Evidence from a regression discontinuity design

摘要： 目的：评估参与联邦医疗保险 D 部分 (Medicare Part D) 的慢性粒细胞白血病 (CML) 患者使用品牌伊马替尼的价格弹性，以确定高额自付费用 (OOP) 是否是导致该人群服药依从性低下的主要原因。 数据来源和研究背景：我们使用 TriNetX Diamond Network (TDN) 美国数据库的数据，涵盖从 2011 年首次上市到 2016 年初仿制药伊马替尼上市并终止专利独占期期间的数据。 研究设计：我们采用模糊不连续回归设计，分别评估 65 岁时参与联邦医疗保险 D 部分对开始使用品牌伊马替尼的新诊断 CML 患者依从性和 OOP 的影响。 估算相应的需求价格弹性 (PED)，并通过多种规范和稳健性检验对结果进行评估。 数据收集/提取方法：分析符合纳入和排除标准的合格患者的数据。 主要发现 我们的分析表明，由于 65 岁时资格扩大，参加 D 部分计划的个人的初始自付额 (OOP) 显著增加了 232 美元（95% 置信区间 (CI)：102 美元至 362 美元）。 依从性仅下降了 6 个百分点（95% CI：-0.21 至 0.08），降幅相对较小且不显著，导致 PED 为 -0.02（95% CI：-0.056，0.015）。 结论 本研究提供了关于共同保险福利设计对开始使用品牌伊马替尼的 Medicare 年龄 CML 患者的财务影响的证据。 结果表明，除了高 OOP 之外，还有其他因素导致了该人群中观察到的大量不依从性，并进一步丰富了关于专科药物 PED 的文献。 显示英文摘要

摘要： Objective To assess the price elasticity of branded imatinib in chronic myeloid leukemia (CML) patients on Medicare Part D to determine if high out-of-pocket payments (OOP) are driving the substantial levels of non-adherence observed in this population. Data sources and study setting We use data from the TriNetX Diamond Network (TDN) United States database for the period from first availability in 2011 through the end of patent exclusivity following the introduction of generic imatinib in early 2016. Study design We implement a fuzzy regression discontinuity design to separately estimate the effect of Medicare Part D enrollment at age 65 on adherence and OOP in newly-diagnosed CML patients initiating branded imatinib. The corresponding price elasticity of demand (PED) is estimated and results are assessed across a variety of specifications and robustness checks. Data collection/extraction methods Data from eligible patients following the application of inclusion and exclusion criteria were analyzed. Principal findings Our analysis suggests that there is a significant increase in initial OOP of $232 (95% Confidence interval (CI): $102 to $362) for individuals that enrolled in Part D due to expanded eligibility at age 65. The relatively smaller and non-significant decrease in adherence of only 6 percentage points (95% CI: -0.21 to 0.08) led to a PED of -0.02 (95% CI: -0.056, 0.015). Conclusion This study provides evidence regarding the financial impact of coinsurance-based benefit designs on Medicare-age patients with CML initiating branded imatinib. Results indicate that factors besides high OOP are driving the substantial non-adherence observed in this population and add to the growing literature on PED for specialty drugs.