Peng Siyang, Tafazzoli Ali, Dorman Emily, Rosenblatt Lisa, Villasis-Keever Angelina, Sorensen Sonja
a a Evidera , Bethesda , MD , USA.
b b Bristol-Myers Squibb Company , Plainsboro , NJ , USA.
J Med Econ. 2015;18(10):763-76. doi: 10.3111/13696998.2015.1046878.
Data from the SINGLE trial demonstrated that 88% of treatment-naïve HIV-1 patients treated with dolutegravir and abacavir/lamivudine (DTG + ABC/3TC) achieved viral suppression at 48 weeks compared with 81% of patients treated with efavirenz/tenofovir disoproxil fumarate/emtricitabine (EFV/TDF/FTC). It is unclear how this difference in short-term efficacy impacts long-term cost-effectiveness of these regimens. This study sought to evaluate long-term cost-effectiveness of DTG + ABC/3TC vs EFV/TDF/FTC from a US payer perspective.
This study is an individual discrete-event simulation which tracked the disease status and treatment pathway of HIV-1 patients. The model simulated treatment over a lifetime horizon by tracking change in patients' CD4 count, clinical events occurrence (opportunistic infections, cancer, and cardiovascular events), treatment switch, and death. The model included up to four lines of treatment. Baseline patient characteristics, efficacy, and safety of DTG + ABC/3TC and EFV/TDF/FTC were informed by data from the SINGLE trial. The efficacy of subsequent treatment lines, clinical event risks, mortality, cost, and utility inputs were based on literature and expert opinion. Outcomes were lifetime discounted medical costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratio (ICER).
Compared with EFV/TDF/FTC, DTG + ABC/3TC increased lifetime costs by $19,153 and per person survival by 0.12 QALYs, resulting in an ICER of $158,890/QALY. ICERs comparing DTG + ABC/3TC to EFV/TDF/FTC remained above the traditional, US willingness-to-pay threshold of $50,000/QALY gained in all scenarios, and above $100,000 or $150,000/QALY gained in most scenarios.
Due to data limitations, the treatment patterns, CD4 count during viral rebound and treatment switch, viral rebound after trial end, and long-term adverse event-related treatment discontinuation were based on assumptions, presented to and approved by clinical experts.
Compared with EFV/TDF/FTC, DTG + ABC/3TC resulted in higher cost and only slightly increased QALYs over a lifetime, with an ICER that exceeded the standard cost-effectiveness threshold. This indicates that the incremental benefit in effectiveness associated with DTG + ABC/3TC may not be worth the incremental increase in costs.
来自单药治疗（SINGLE）试验的数据表明，初治的HIV-1患者中，接受多替拉韦与阿巴卡韦/拉米夫定（DTG+ABC/3TC）治疗的患者在48周时病毒抑制率为88%，而接受依非韦伦/替诺福韦酯/恩曲他滨（EFV/TDF/FTC）治疗的患者这一比例为81%。目前尚不清楚这种短期疗效差异如何影响这些治疗方案的长期成本效益。本研究旨在从美国医保支付方的角度评估DTG+ABC/3TC与EFV/TDF/FTC的长期成本效益。
本研究是一项个体离散事件模拟，追踪HIV-1患者的疾病状态和治疗路径。该模型通过追踪患者CD4细胞计数的变化、临床事件的发生（机会性感染、癌症和心血管事件）、治疗转换和死亡情况，模拟患者一生的治疗过程。该模型包括多达四条治疗线。DTG+ABC/3TC和EFV/TDF/FTC的基线患者特征、疗效和安全性依据SINGLE试验的数据。后续治疗线的疗效、临床事件风险、死亡率、成本和效用输入基于文献和专家意见。结果指标为一生的贴现医疗成本、质量调整生命年（QALY）和增量成本效益比（ICER）。
与EFV/TDF/FTC相比，DTG+ABC/3TC使一生成本增加19,153美元，人均生存期增加0.12个QALY，ICER为158,890美元/QALY。在所有情况下，将DTG+ABC/3TC与EFV/TDF/FTC进行比较的ICER均高于传统的美国支付意愿阈值50,000美元/QALY，在大多数情况下高于100,000美元或150,000美元/QALY。
由于数据限制，治疗模式、病毒反弹和治疗转换期间的CD4细胞计数、试验结束后的病毒反弹以及与长期不良事件相关的治疗中断均基于假设，并经临床专家审核通过。
与EFV/TDF/FTC相比，DTG+ABC/3TC导致成本更高，一生的QALY仅略有增加，ICER超过了标准成本效益阈值。这表明与DTG+ABC/3TC相关的有效性增量效益可能不值得成本的增量增加。
