脂質異常症に対するフィブラート対スタチンの薬剤経済分析

抄録

[Objectives] It has been demonstrated that HMG-CoA reductase inhibitors (statins) effectively reduce the low-density lipoprotein cholesterol (LDL-C) and total cholesterol levels in the blood, and currently, statins are most widely used for the treatment of hyperlipidemia.  On the other hand, it has been demonstrated that fibrates more effectively reduce the blood triglyceride level (TG).  However, concomitant use of statins and fibrates is contraindicated.
  Therefore, practical and situational use of fenofibrate (fibrate therapy) and atorvastatin (statin therapy) was investigated in patients with high TG and LDL-C levels in consideration of cost effectiveness.
[Method] Baseline TG and LDL-C levels were stratified, and a table of combination was prepared for TG and LDL-C values.  Effectiveness was measured by the number of patients who were able to achieve treatment targets.  Treatment targets were set referring to the reduction rate of serum lipid levels in dose finding studies of fenofibrate and atorvastatin and the target lipid levels identified in 2007 Japan Atherosclerosis Society Guidelines for Prevention of Atherosclerotic Cardiovascular Diseases.  Costs were measured by annual drug treatment costs, and the incremental cost effectiveness ratio of atorvastatin to fenofibrate was then estimated.  According to the actual patient distribution, the incremental cost effectiveness ratio of atorvastatin to fenofibrate in patients with TG level over 150 mg and LDL level over 140 mg was also estimated.
[Results] Fenofibrate was dominant over atorvastatin where effectiveness was higher and costs were lower in fenofibrate treatment in two patient groups; patients with LDL-C level under 160 mg patients with TG level over 170 mg and LDL-C level between 160 mg and 170 mg patients with TG level over 190 mg and LDL-C level between 170 mg and 180 mg patients with TG level over 230 mg and LDL-C level between 180 mg and 190 mg patients with TG level over 250 mg and LDL-C level between 190 mg and 200 mg patients with TG level over 290 mg and LDL-C level between 200 mg and 210 mg patients with TG level over 350 mg and LDL-C level over 210 mg.  In an analysis made according to the actual patient distribution, 571 fenofibrate patients and 534 atorvastatin patients were able to achieve the treatment targets, and fenofibrate was dominant over atorvastatin where effectiveness was higher and costs were lower in fenofibrate treatment.