A break-even price calculation for the use of sirolimus-eluting stents in angioplasty

Drug-eluting stents: from evidence to policy

Drug-eluting stents are a major breakthrough in cardiology, with the Cypher (Cordis Corporation) and Taxus (Boston Scientific) stents preventing 60-70% of repeat coronary revascularizations, compared with bare metal stents. Both evidence- and risk-based application of drug-eluting stents is expected to create relevant financial and equity problems to most public hospitals, as the cost of drug-eluting stents is over 1000 higher than traditional stents. In the perspective of third-party payers, drug-eluting stents are cost-effective revascularization strategies for a large portion of patients actually undergoing stenting. However, adequate guidelines and reimbursement strategies are still awaited in several countries.

Economic evaluation of drug-eluting stents compared to bare metal stents using a large prospective study in Ontario

Objectives:To determine the cost-effectiveness (CE) and cost-utility (CU) of drug-eluting stents (DES) compared to bare metal stents (BMS) in Ontario using a large prospective “real-world” cohort study and determine the extent to which results vary by patient risk subgroups.

Methods:A field evaluation was conducted based on all stent procedures in the province of Ontario between December 1, 2003, and March 31, 2005, with a minimum subject follow-up of 1 year. Effectiveness data from the study using a propensity-score matched cohort were combined with resource utilization and cost data and quality of life (QOL) data from the published literature in a decision analytic modeling framework to determine 2-year cost-effectiveness (cost per revascularization avoided) and cost-utility (cost per quality-adjusted life-year ([QALY] gained). Stochastic model parameter uncertainty was expressed using probability distributions and analyzed using a probabilistic model. Modeling assumptions were assessed using traditional deterministic sensitivity analysis.

Results:Significant differences in revascularization rates were found for patients with two or more high risk factors. Despite these differences, the CE and CU of DES remained high (e.g., $419,000 per QALY gained in the most favorable patient risk subgroup). In sensitivity analysis, the difference in cost between DES and BMS had an impact on the CE and CU results. For example, at a price differential of $500, the CU of DES was $20,000/QALY for one patient subgroup and DES was dominant (i.e., less costly and more effective) in another.

Conclusions:At current prices, the CE/CU of DES compared with BMS is high even in patient high risk subgroups. As the relative price of DES decrease, the value for money attractiveness of DES increases, especially for selected high risk patients.

The cost-effectiveness of drug-eluting stents: a systematic review

BACKGROUND

Drug-eluting stents have been seen as an attractive alternative to bare-metal stents for percutaneous coronary interventions (PCIs) because of the decreased need for revascularization. However, comparative clinical trials have shown no difference in patient outcomes, and drug-eluting stents are considerably more expensive than their bare-metal counterparts. We conducted a systematic review of all published comparative cost-effectiveness analyses to identify the factors contributing to the heterogeneity of their conclusions.

METHODS

We retrieved all articles published between Jan. 1, 2000, and July 31, 2006, in which the cost-effectiveness, from a third-party payer perspective, of drug-eluting stents was compared with that of bare-metal stents for PCI in unrestricted patient populations. Electronic databases, Web sites from health technology assessment groups and references of identified articles were searched. Our outcome variable was whether the study's conclusions favoured widespread use of drug-eluting stents, as assessed by 4 independent reviewers. Study characteristics such as quality, funding source, country and year of publication were extracted. Two-by-2 tables and Fisher's exact test were used to study the association between covariates and the outcome variable. A classification and regression tree (CART) model was used for multivariate analysis.

RESULTS

We identified 19 cost-effectiveness analyses. Ten were in favour of widespread use of drug-eluting stents, and 9 favoured more restrained use. Only 1 of 9 high-quality studies supported widespread use, as compared with 9 of 10 lower quality studies (p < 0.001). All of the 7 sponsored studies argued in favour of widespread use, as compared with 3 of the 12 studies without sponsorship (p = 0.003). Studies from the United States were more likely than those from other countries to endorse unlimited use (p = 0.032). A CART model with 2 covariates--study quality and sponsorship--provided the best fit (error rate 10.5%).

INTERPRETATION

Conclusions drawn by cost-effectiveness analyses of drug-eluting stents for PCI are associated with the study's quality, funding source and country of origin. Vigilance regarding these study characteristics is required when interpreting findings from cost-effectiveness analyses.

What reimbursement for coronary revascularization with drug-eluting stents?

We investigated the clinical and economic impact of sirolimus-eluting coronary stents (SES) at a nationwide level as to advice about the feasible reimbursement policy for the Italian Health Care System (SSN). A decision model compared bare metal stents (BMS) and SES in terms of costs and repeat coronary revascularizations incurred in 12 months following the first revascularization. The model was compiled for eight subgroups of patients. Rates of events were derived from randomized trials and an 1,809-patient survey. National charges were used to evaluate resources consumption. Compared with BMS, the number of averted revascularizations with SES is 0.16 per patient. SES also save Euro 1,371 per patient. Total savings to SSN are proportional to the rate of SES adoption by Italian hospitals: assuming a complete replacement of BMS with SES, the model estimates that 7,095 revascularizations would be averted and more than Euro 60 million saved by the SSN in 1 year. To stimulate SES adoption a SES-specific DRG might by introduced with a reimbursement value 23% higher than the current charge. SES is thus a cost-saving strategy in the perspective of the SSN that could therefore support the introduction of the new technology by reimbursing about 80% of its current incremental acquisition cost.