Cost effectiveness of ramipril in patients at high risk for cardiovascular events : economic evaluation of the HOPE (Heart Outcomes Prevention Evaluation) study for Germany from the Statutory Health Insurance perspective

Review: PROactive 03: Pioglitazone, type 2 diabetes and reducing macrovascular events — economic implications?

conomic value of medicines, medical devices and other technologies is an increasingly important consideration in healthcare management. Conducting high quality economic analyses alongside randomised controlled clinical trials (RCTs) is desirable since these offer timely information with high internal validity. The recent publication of the landmark PROactive study provides a relevant platform upon which to base a detailed economic evaluation of the possible additional benefit of pioglitazone over and above current best treatment in patients with type 2 diabetes with severe cardiovascular (CV) disease. Pioglitazone improved CV outcome and reduced the need to add insulin to existing therapy in individuals at high risk of further macrovascular events. The predefined economic analysis of this study using well-accepted methods will inform the cost effectiveness (CE) of pioglitazone confirming (or not) its value in the management of patients with type 2 diabetes with severe CV disease.

Cost-effectiveness of zofenopril in patients with left ventricular systolic dysfunction after acute myocardial infarction: a post hoc analysis of SMILE-4

BACKGROUND

In SMILE-4 (the Survival of Myocardial Infarction Long-term Evaluation 4 study), zofenopril + acetylsalicylic acid (ASA) was superior to ramipril + ASA in reducing the occurrence of major cardiovascular events in patients with left ventricular dysfunction following acute myocardial infarction. The present post hoc analysis was performed to compare the cost-effectiveness of zofenopril and ramipril.

METHODS

In total, 771 patients with left ventricular dysfunction and acute myocardial infarction were randomized in a double-blind manner to receive zofenopril 60 mg/day (n = 389) or ramipril 10 mg/day (n = 382) + ASA 100 mg/day and were followed up for one year. The primary study endpoint was the one-year combined occurrence of death or hospitalization for cardiovascular causes. The economic analysis was based on evaluation of cost of medications and hospitalizations and was applied to the intention-to-treat population (n = 716). Cost data were drawn from the National Health Service databases of the European countries participating in the study. The incremental cost-effectiveness ratio was used to quantify the cost per event prevented with zofenopril versus ramipril.

RESULTS

Zofenopril significantly (P = 0.028) reduced the risk of the primary study endpoint by 30% as compared with ramipril (95% confidence interval, 4%-49%). The number needed to treat to prevent a major cardiovascular event with zofenopril was 13 less than with ramipril. The cost of drug therapies was higher with zofenopril (328.78 Euros per patient per year, n = 365) than with ramipril (165.12 Euros per patient per year, n = 351). The cost related to the occurrence of major cardiovascular events requiring hospitalization averaged 4983.64 Euros for zofenopril and 4850.01 Euros for ramipril. The incremental cost-effectiveness ratio for zofenopril versus ramipril was 2125.45 Euros per event prevented (worst and best case scenario in the sensitivity analysis was 3590.09 and 3243.96 Euros, respectively).

CONCLUSION

Zofenopril is a viable and cost-effective treatment for managing patients with left ventricular dysfunction after acute myocardial infarction.

Cost-effectiveness of enzyme replacement therapy for Fabry disease

Background

The cost-effectiveness of enzyme replacement therapy (ERT) compared to standard medical care was evaluated in the Dutch cohort of patients with Fabry disease.

Methods

Cost-effectiveness analysis was performed using a life-time state-transition model. Transition probabilities, effectiveness data and costs were derived from retrospective data and prospective follow-up of the Dutch study cohort consisting of males and females aged 5–78 years. Intervention with ERT (either agalsidase alfa or agalsidase beta) was compared to the standard medical care. The main outcome measures were years without end organ damage (renal, cardiac en cerebrovascular complications), quality adjusted life years (QALYs), and costs.

Results

Over a 70 year lifetime, an untreated Fabry patient will generate 55.0 years free of end-organ damage (53.5 years in males, 56.9 years in females) and 48.6 QALYs (47.8 in males, 49.7 in females). Starting ERT in a symptomatic patient increases the number of years free of end-organ damage by 1.5 year (1.6 in males, 1.3 in females), while the number of QALYs gained increases by a similar amount (1.7 in males, 1.4 in females). The costs of ERT starting in the symptomatic stage are between €9 - €10 million (£ 7.9 - £ 8.8 million, $13.0- $14.5 million) during a patient’s lifetime. Consequently, the extra costs per additional year free of end-organ damage and the extra costs per additional QALY range from €5.5 - €7.5 million (£ 4.8 – £ 6.6 million, $ 8.0 – $ 10.8 million), undiscounted.

Conclusions

In symptomatic patients with Fabry disease, ERT has limited effect on quality of life and progression to end organ damage. The pharmaco-economic evaluation shows that this modest effectiveness drives the costs per QALY and the costs per year free of end-organ damage to millions of euros. Differentiation of patients who may benefit from ERT should be improved to enhance cost-effectiveness.

Costs of stroke using patient-level data: a critical review of the literature

BACKGROUND AND PURPOSE

With decision-analytic models becoming more popular to assess the cost-effectiveness of health care interventions, the need for robust estimates on the costs of cerebrovascular disease is paramount. This study reports the results from a literature review of the costs of cerebrovascular diseases, and assesses the quality of the published evidence against a set of defined criteria.

METHODS

A broad literature search was conducted. Those studies reporting mean/median costs of cerebrovascular diseases derived from patient-level data in a developed country setting were included. Data were abstracted using standardized reporting forms and assessed against 4 predefined criteria: use of adequate methodologies, use of a population-based study, inclusion of premorbid resource use, and reporting of costs by different patient subgroups.

RESULTS

A total of 120 cost studies were identified. The cost estimates of stroke were compared by taking into account the effects of inflation and price differentials between countries. Average costs of stroke ranged from $468 to $146 149. Differences in costs were also found within country, with estimates in the USA varying 20-fold. Although the costing methodologies used were generally appropriate, only 5 studies were based on population-based studies, which are the gold standard study design when comparing incidence, outcome, and costs.

CONCLUSIONS

This review showed large variations in the costs of stroke, mainly attributable to differences in the populations studied, methods, and cost categories included. The wide range of cost estimates could lead to selection bias in secondary health economic analyses, with authors including those costs that are more likely to produce the desired results.

Determining the cost-effectiveness of preventing cardiovascular disease: are estimates calculated over the duration of a clinical trial adequate?

BACKGROUND

Economic analyses of randomized clinical trials often focus only on the results that are observed during the study. However, for many preventive interventions, associated costs and benefits will accrue over a patient's remaining lifetime. To determine the importance of the chosen time horizon, the cost-effectiveness (C/E) of ramipril therapy was calculated and compared in the Heart Outcomes Prevention Evaluation (HOPE), the Microalbuminuria, Cardiovascular, and Renal Outcomes in HOPE (MICRO-HOPE) and the Acute Infarction Ramipril Efficacy (AIRE) study versus the entire life expectancy (L/E) of potential patients.

METHODS

The Cardiovascular Disease Life Expectancy model, a validated Markov model, was calibrated to accurately forecast the results of each trial. These results were then extrapolated over the remaining L/E of hypothetical patients 55 to 75 years of age. The predicted change in L/E and associated direct health care costs for Canadians were calculated and discounted 3% annually.

RESULTS

In HOPE, the forecasted increased L/E averaged 0.06 years during the five-year study versus 1.3 years over the remaining years of L/E. The associated C/E of ramipril was $15,000 per year of life saved (YOLS) over the study duration and $8,500/YOLS over the remaining lifetime. For hypothetical patients, the C/E of ramipril over 4.5 years ranged from $6,700/YOLS to more than $58,300/YOLS and was lowest among elderly men. When the remaining L/E was considered, the C/E of ramipril was similar for men and women of all ages, ranging from $8,100/YOLS to $10,200/YOLS. The analyses of MICRO-HOPE and AIRE provided similar results.

CONCLUSION

The estimated efficacy and associated C/E of ramipril in HOPE, MICRO-HOPE and the AIRE study is extremely sensitive to the selected time horizon. Economic analyses beyond the duration of randomized clinical trials are required to fully evaluate the potential costs and benefits of long-term preventive therapies.

Estimating the cost effectiveness of ramipril used for specific clinical indications: comparing the outcomes in four clinical trials with a common economic model

BACKGROUND AND OBJECTIVES

Economic analyses of drug therapies are highly dependent on the clinical indications for treatment. The cost effectiveness of ramipril has been evaluated in numerous studies, usually based on the results of one specific clinical trial. We estimated the cost effectiveness of this drug across a range of currently accepted therapeutic indications, using a single health economic model and adjusted for quality of life, to compare the different outcomes observed in four clinical trials.

METHODS

The cardiovascular life expectancy model, a validated Markov model, was calibrated to accurately forecast the results of four trials including AIRE, HOPE, Micro-HOPE, and REIN. We then extrapolated these results over the remaining life expectancy of the patients enrolled in each study and adjusted for the quality of life associated with the observed outcomes. The cost per quality-adjusted life-year (QALY) was then calculated from the perspective of the Canadian healthcare system incorporating the estimated direct healthcare costs associated with treatments and outcomes.

RESULTS

After discounting all costs and outcomes 3% annually, the benefits associated with ramipril ranged from 0.74 QALYs in the AIRE study to 1.22 QALYs in Micro-HOPE. Treatment was estimated to be cost-saving for some patient groups, such as those in REIN. The highest cost-effectiveness ratio was observed among individuals enrolled in HOPE ($Can20 000 per QALY in 2002).

CONCLUSION

Treatment with ramipril appears to be economically attractive across a wide range of patient groups, including those with increased coronary risk and/or diabetes mellitus (HOPE and Micro-HOPE), those with congestive heart failure (AIRE), and those with non-diabetic nephropathy (REIN).

Pharmaco-economic issues for diabetes therapy

A systematic review was undertaken to analyse pharmaco-economic issues in diabetes, with evidence selected on the basis of relevance and immediacy. Pharmaco-economics in diabetes primarily relates to making choices about antidiabetic pharmaceuticals, and this is being influenced by global trends. Trends include increasing numbers of patients with diabetes, with increasing costs of caring for people with diabetes, and an ever-present focus on the costs of pharmaceuticals which are predicted to increase as the pace of development of new medications parallels the increasing incidence of the condition. These developments have influenced the demand for health care in diabetes in the last decade, and will continue to determine this in the coming decade. Recent national experiences are cited to illustrate current issues and to focus specifically upon the challenges facing a raft of new diabetes treatment options now hitting the marketplace, although supported by fewer completed long-term trials. It can be anticipated that these newer agents will be appraised for their cost-effectiveness or value for money. Economic analyses for some of the new technologies are summarized; in general, the peer-reviewed publications using well-accepted and validated models have reported that these technologies are cost-effective. Endorsement of any technology in a national setting is not awarded simply because the incremental cost-effectiveness ratio (ICER) falls below the threshold regarded as value for money. In most national observations the reviewers expressed concerns about assumptions used in economic modelling which resulted in the ICERs being deemed optimistic at best, generally highly uncertain, and resulting in the cost-effectiveness appearing better than it really would be in clinical practice. This has often led to the authorities concluding that the price advantage of new technologies over comparators could not be justified, essentially leading to restrictions in use compared to their licence. In general, a paucity of robust evidence on longer-term outcome data together with a lack of health-related quality of life (HRQOL) data collected in a reliable manner in appropriate patients and amenable to utility (and hence quality adjusted life year or QALY) estimation have resulted in problems for these new drugs at the so-called fourth (cost-effectiveness) hurdle. In the light of these findings, the implications for generating credible fit-for-purpose cost-effectiveness analyses of new technologies in diabetes are discussed. Throughout this chapter, the interested reader is referred to a number of excellent review articles for further details.

Long-term cost-effectiveness of clopidogrel in patients with acute coronary syndrome without ST-segment elevation in Germany

Patients with acute coronary syndrome without ST-segment elevation receiving clopidogrel in addition to acetylsalicylic acid (ASA) showed a 20% risk reduction in comparison to patients receiving ASA monotherapy (CURE trial). Economic models for assessing the impact on costs exist for several countries but not for Germany on a long-term basis. The objective of this model adaptation is to assess the long-term economic impact of clopidogrel taken in addition to ASA in Germany. A Markov model with six states [at risk, first year with stroke, following years with stroke, first year with new myocardial infarction (MI), following years with MI, and death] was adapted for Germany. Model outcome was life-years saved. Effects of 1-year treatment were calculated based on the CURE trial. Resource use for the different health states was based on published data, which included costs for drugs, outpatient care, hospitalization, rehabilitation and nursing. Risk data for MI and stroke were based on Swedish data and validated for the German adaptation. The model calculates lifetime costs and survival length. Costs were estimated from the payers' perspective. A series of one-way sensitivity analyses was conducted (follow-up costs, discount rates). The Markov analysis predicts a survival of 8.89years in the placebo treatment group and 9.02 years in the clopidogrel treatment group. The cumulated costs were euro 8,548 and euro 8,953, respectively. The incremental cost-effectiveness ratio (ICER) was euro 3,113 for each life-year saved. The model was robust regarding variations in key parameters in the sensitivity analysis, resulting in a range of ICER from euro 1,338 to euro 9,322. Our results are in line with the results for other healthcare systems. Adding clopidogrel to ASA for patients with acute coronary syndrome without ST-segment elevation generated an additional life-year saved at a comparably low value of euro 3,113. One-year treatment with clopidogrel is a cost-effective treatment option in patients with acute coronary syndrome from the perspective of a third-party payer in Germany.

Pharmacoeconomics of angiotensin II antagonists in type 2 diabetic patients with nephropathy: implications for decision making

Angiotensin II receptor antagonists (angiotensin II receptor blockers; ARBs) are a class of antihypertensive drugs that are generally considered comparable to ACE inhibitors in the prevention of heart and kidney failure. However, these two classes of agents do interfere in different stages of the renin-angiotensin system. In patients with type 2 diabetes mellitus, advantages for ARBs over conventional (non-ACE inhibitor) therapy on progression from micro- to macroalbuminuria and overt nephropathy and end-stage renal disease have been shown in clinical trials. In patients with type 2 diabetes and end-stage renal disease, the need for dialysis and/or transplantation results in the use of major healthcare resources. This paper reviews the available economic evidence on treatment with ARBs in type 2 diabetic patients with advanced renal disease.Within-trial analytic and Markov model economic evaluations of the RENAAL (Reduction of Endpoint in Non-insulin dependent diabetes mellitus with Angiotensin II Antagonist Losartan), IDNT (Irbesartan Diabetic Nephropathy Trial) and IRMA (IRbesartan in type 2 diabetes with MicroAlbuminuria)-2 studies suggest that treatment with ARBs in patients with type 2 diabetes with overt or incipient nephropathy confers health gains and net cost savings compared with conventional (non-ACE inhibitor) therapy. For reimbursement and reference pricing decisions, there is a need for a head-to-head comparison of an ACE inhibitor with ARBs to model all possible costs and effects of ACE inhibitors and ARBs. This will result in a proper pharmacoeconomic outcome, where both types of drugs can be compared for healthcare decisions.