Simpson Kit N, Jones Walter J, Rajagopalan Rukmini, Dietz Birgitta
Department of Health Administration and Policy, College of Health Professions, Medical University of South Carolina, Charleston, SC 29425, USA.
Clin Drug Investig. 2007;27(7):443-52. doi: 10.2165/00044011-200727070-00001.
To estimate the cost effectiveness and long-term combined effects of HIV disease and antiretroviral (ARV) therapy-related risk for coronary heart disease (CHD) on quality-adjusted survival and healthcare costs for ARV-experienced patients.
A previously validated Markov model was updated and supplemented with the Framingham CHD risk equation. The representative patient in the model was male, aged 37 years and had a baseline 10-year CHD risk of 4.6%. Patients started with either lopinavir/ritonavir (LPV/r) or ritonavir-boosted atazanavir (ATV+RTV) as the protease inhibitor (PI). The proportions of patients with viral suppression below 400 and 50 copies/mL, respectively, at week 48 reported in clinical trials were used to estimate the differences between these two therapies. The daily ARV costs were $US 24.60 for LPV/r capsules (2005 costs) and $US 26.54 for LPV/r tablets (2006 costs), $US 29.76 for ATV and $US 8.57 for ritonavir (2005 costs). Costs of other ARV drugs were taken from average wholesale drug reports for 2005. The cost of AIDS events was estimated from Medicaid billing databases and reflected a medical care system perspective and 2005 treatment costs. Cost-effectiveness calculations assumed a lifetime time horizon. The effects of different model assumptions were tested in a multiway sensitivity analysis by combining extreme values of parameters.
The model estimated a clinical and economic advantage to using LPV/r over ATV+RTV, which varied depending upon the use of LPV/r capsules or tablets. Using LPV/r capsules was comparatively beneficial for ARV-experienced patients in quality-adjusted life-months (QALMs) of 4.6 (corrected for differences in CHD risk) compared with ATV+RTV. In addition, there were 5- and 10-year overall per-patient cost savings of $US 17,995 and $US 21,298, respectively. Estimates for the LPV/r tablet formulation approved in 2005 (assuming similar efficacy) improved cost savings over 5- and 10-year periods to $US 19,598 and $US 23,126 per patient, respectively, because of a drug price differential. Sensitivity analysis tested numerous assumptions about the model cost and efficacy parameters and found that the results were robust to most changes. Model limitations were the uncertainty associated with the model parameters used.
LPV/r appears to be a highly cost-effective regimen relative to ATV+RTV for the treatment of HIV. The long-term CHD risk associated with LPV/r was minimal compared with the increased risk of AIDS/death and costs projected for a less efficacious PI-based regimen.
评估人类免疫缺陷病毒（HIV）疾病及抗逆转录病毒（ARV）治疗相关的冠心病（CHD）风险对接受过ARV治疗患者的质量调整生存期和医疗费用的成本效益及长期综合影响。
对一个先前验证过的马尔可夫模型进行更新，并补充弗雷明汉姆冠心病风险方程。模型中的代表性患者为37岁男性，基线10年冠心病风险为4.6%。患者起始使用洛匹那韦/利托那韦（LPV/r）或利托那韦增强的阿扎那韦（ATV+RTV）作为蛋白酶抑制剂（PI）。临床试验中报告的第48周病毒抑制水平分别低于400和50拷贝/mL的患者比例用于估计这两种治疗方法之间的差异。LPV/r胶囊的每日ARV成本为24.60美元（2005年成本），LPV/r片剂为26.54美元（2006年成本），ATV为29.76美元，利托那韦为8.57美元（2005年成本）。其他ARV药物的成本取自2005年的平均批发药品报告。艾滋病事件的成本根据医疗补助计费数据库估算，反映了医疗保健系统的视角和2005年的治疗成本。成本效益计算假设为终身时间范围。通过组合参数的极值在多因素敏感性分析中测试不同模型假设的影响。
模型估计使用LPV/r相对于ATV+RTV在临床和经济方面具有优势，这取决于使用LPV/r胶囊还是片剂而有所不同。与ATV+RTV相比，使用LPV/r胶囊对于接受过ARV治疗的患者在质量调整生命月（QALMs）方面有4.6的优势（校正了冠心病风险差异）。此外，每位患者在5年和10年的总体成本分别节省17,995美元和21,298美元。2005年批准的LPV/r片剂配方（假设疗效相似）由于药物价格差异，在5年和10年期间每位患者的成本节省分别提高到19,598美元和23,126美元。敏感性分析测试了关于模型成本和疗效参数的众多假设，发现结果对大多数变化具有稳健性。模型的局限性在于与所使用的模型参数相关的不确定性。
相对于ATV+RTV，LPV/r似乎是一种治疗HIV的高成本效益方案。与基于疗效较差的PI方案预计的艾滋病/死亡风险增加和成本相比，LPV/r相关的长期冠心病风险极小。
