Cost effectiveness of ezetimibe in patients with cardiovascular disease and statin intolerance or contraindications: a Markov model

PCSK9 inhibitor, ezetimibe, and bempedoic acid: Evidence-based therapies for statin-intolerant patients

Statins are first-line therapy for treating dyslipidemia because of their low-density lipoprotein cholesterol (LDL-C) lowering efficacy, superior event-reduction data and unrivaled cost-effectiveness. Yet, many people are intolerant of statins, whether due to true adverse events or the nocebo effect, so within one year about two-thirds of primary prevention patients and one-third of secondary prevention patients are no longer taking their prescription. Statins still dominate this landscape, but other agents, often used in combination, potently reduce LDL-C levels, regress atherosclerosis and lower risk of major adverse cardiovascular events (MACE). Ezetimibe lowers LDL-C by reducing intestinal absorption of cholesterol. Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) lower LDL-C by increasing the number and durability of hepatic LDL receptors. Bempedoic acid reduces hepatic cholesterol synthesis. Ezetimibe, PCSK9i and bempedoic are evidence-based, non-statin therapies that synergistically lower LDL-C and reduce risk of MACE; they also have benign side-effect profiles and are generally well tolerated.

Cost-effectiveness of Ezetimibe plus statin lipid-lowering therapy: A systematic review and meta-analysis of cost-utility studies

In addition to statin therapy, Ezetimibe, a non-statin lipid-modifying agent, is increasingly used to reduce low-density lipoprotein cholesterol and atherosclerotic cardiovascular disease risk. Literature suggests the clinical effectiveness of Ezetimibe plus statin (EPS) therapy; however, primary evidence on its economic effectiveness is inconsistent. Hence, we pooled incremental net benefit to synthesise the cost-effectiveness of EPS therapy. We identified economic evaluation studies reporting outcomes of EPS therapy compared with other lipid-lowering therapeutic agents or placebo by searching PubMed, Embase, Scopus, and Tufts Cost-Effective Analysis registry. Using random-effects meta-analysis, we pooled Incremental Net Benefit (INB) in the US $ with a 95% confidence interval (CI). We used the modified economic evaluations bias checklist and GRADE quality assessment for quality appraisal. The pooled INB from twenty-one eligible studies showed that EPS therapy was significantly cost-effective compared to other lipid-lowering therapeutic agents or placebo. The pooled INB (95% CI) was $4,274 (621 to 7,927), but there was considerable heterogeneity (I² = 84.21). On subgroup analysis EPS therapy is significantly cost-effective in high-income countries [$4,356 (621 to 8,092)], for primary prevention [$4,814 (2,523 to 7,106)], and for payers’ perspective [$3,255 (571 to 5,939)], and from lifetime horizon [$4,571 (746 to 8,395)]. EPS therapy is cost-effective compared to other lipid-lowering therapeutic agents or placebo in high-income countries and for primary prevention. However, there is a dearth of evidence from lower-middle-income countries and the societal perspective.

Emerging Non-statin Treatment Options for Lowering Low-Density Lipoprotein Cholesterol

Low-density lipoprotein cholesterol (LDL-C) is a modifiable risk factor for the development of atherosclerotic cardiovascular disease. Statins have been the gold standard for managing cholesterol levels and reducing the risks associated with atherosclerotic cardiovascular disease; however, many patients do not achieve their cholesterol goals or are unable to tolerate this drug class due to adverse drug events. Recent studies of non-statin cholesterol lowering drugs (i.e., ezetimibe, PCSK9 inhibitors) have demonstrated cardiovascular benefits; and new drugs [i.e., bempedoic acid (BDA), inclisiran] have produced promising results in pre-clinical and clinical outcome trials. This narrative review aims to discuss the place in therapy of ezetimibe, PCSK9 inhibitors, BDA, and inclisiran and describe their relative pharmacokinetic (PK) profiles, efficacy and safety as monotherapy and combination therapy, and cardiovascular benefit(s) when used for hypercholesterolemia.

Cost-Effectiveness Analysis of Ezetimibe as the Add-on Treatment to Moderate-Dose Rosuvastatin versus High-Dose Rosuvastatin in the Secondary Prevention of Cardiovascular Diseases in China: A Markov Model Analysis

BACKGROUND

For patients with inadequate control of cholesterol using moderate-dose statins in the secondary prevention of cardiovascular diseases (CVD), either doubling the dose of statins or adding ezetimibe should be considered. The cost-effectiveness of them is unknown in the Chinese context. The aim of this study is to compare the cost and effectiveness of the two regimens, and estimate the incremental cost-effectiveness ratio (ICER).

METHODS

A Markov model of five health statuses were used to estimate long-term costs and quality-adjusted life-years (QALYs) of the two treatment regimens from the healthcare perspective. The effectiveness data used to calculate the transition probability was based on a previously published randomized trial. The utility data was gathered from literature and the costs were gathered from the electronic medical record system of West China Hospital in Chinese Yuan (CNY) in 2017 price. One-way sensitivity analysis and probabilistic sensitivity analysis were conducted.

RESULTS

The ICER for ezetimibe plus moderate-dose rosuvastatin was 47,102.99 CNY per QALY for 20 years simulation, which did not reach the threshold of per capita gross domestic product (GDP) of 59,660 CNY per QALY in 2017 in China. Non-CVD-related mortality and CVD-related mortality contributed most to the ICER.

CONCLUSION

Adding ezetimibe to the moderate-dose statin in secondary prevention for CVD is cost-effective, compared with the high-dose statin in the Chinese context whose low-density lipoprotein cholesterol (LDL-c) was not inadequately controlled by moderate-dose statin alone.

Modelling the cost-effectiveness of PCSK9 inhibitors vs. ezetimibe through LDL-C reductions in a Norwegian setting

Aims

Despite the success of statins, there remains unmet clinical need in cardiovascular disease (CVD) prevention. New proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors reduce low-density lipoprotein cholesterol (LDL-C) by 55-65%. Two PCSK9 inhibitors, evolocumab, and alirocumab, were approved for use in Norway but not yet for reimbursement through public national insurance. We aim to explore the cost-effectiveness of these compared with available treatments in a Norwegian setting.

Methods and results

A state transition Markov model was developed to model the cost-effectiveness of PCSK9 inhibitors for prevention of coronary heart disease, ischaemic strokes, and death among high-risk patient subpopulations in Norway, in both primary and secondary settings. Evolocumab and alirocumab are compared against ezetimibe and standard treatment. Risk of CVD is based on population incidence rates and adjusted according to baseline risk factors. Preventative effect of treatment was modelled according to absolute reduction in LDL-C. PCSK9 inhibitors were never found to be cost-effective in primary prevention. In secondary prevention they were cost-effective only for older, high-risk patients. The lowest cost-effectiveness ratios were for heterozygous familial hypercholesterolaemia patients and high-risk diabetics, with €63 200 and €68 400 per quality-adjusted life-year, respectively.

Conclusion

High lifetime costs of PCSK9 inhibitors may not be offset by estimated health gains for most eligible patients. PCSK9 inhibitors are found in the model only to be cost-effective in secondary prevention for older patients with high absolute risk of CVD. This picture is likely to change as price decreases. Future research is needed to determine the long-term preventative effects of PCSK9 inhibitors.

The effectiveness and cost-effectiveness of plant sterol or stanol-enriched functional foods as a primary prevention strategy for people with cardiovascular disease risk in England: a modeling study

This study appraises the effectiveness and cost-effectiveness of consumption of plant sterol-enriched margarine-type spreads for the prevention of cardiovascular disease (CVD) in people with hypercholesterolemia in England, compared to a normal diet. A nested Markov model was employed using the perspective of the British National Health Service (NHS). Effectiveness outcomes were the 10-year CVD risk of individuals with mild (4-6 mmol/l) and high (above 6 mmol/l) cholesterol by gender and age groups (45-54, 55-64, 65-74, 75-85 years); CVD events avoided and QALY gains over 20 years. This study found that daily consumption of enriched spread reduces CVD risks more for men and older age groups. Assuming 50% compliance, 69 CVD events per 10,000 men and 40 CVD events per 10,000 women would be saved over 20 years. If the NHS pays the excess cost of enriched spreads, for the high-cholesterol group, the probability of enriched spreads being cost-effective is 100% for men aged over 64 years and women over 74, at £20,000/QALY threshold. Probabilities of cost-effectiveness are lower at younger ages, with mildly elevated cholesterol and over a 10-year time horizon. If consumers bear the full cost of enriched spreads, NHS savings arise from reduced CVD events.

Economic evaluation of ezetimibe treatment in combination with statin therapy in the United States

AIMS

This study assessed the cost-effectiveness of ezetimibe with statin therapy vs statin monotherapy from a US payer perspective, assuming the impending patent expiration of ezetimibe.

METHODS

A Markov-like economic model consisting of 28 distinct health states was used. Model population data were obtained from US linked claims and electronic medical records, with inclusion criteria based on diagnostic guidelines. Inputs came from recent clinical trials, meta-analyses, and cost-effectiveness analyses. The base-case scenario was used to evaluate the cost-effectiveness of adding ezetimibe 10 mg to statin in patients aged 35-74 years with a history of coronary heart disease (CHD) and/or stroke, and with low-density lipoprotein cholesterol (LDL-C) levels ≥70 mg/dL over a lifetime horizon, assuming a 90% price reduction of ezetimibe after 1 year to take into account the impending patent expiration in the second quarter of 2017. Sub-group analyses included patients with LDL-C levels ≥100 mg/dL and patients with diabetes with LDL-C levels ≥70 mg/dL.

RESULTS

The lifetime discounted incremental cost-effectiveness ratio (ICER) for ezetimibe added to statin was $9,149 per quality-adjusted life year (QALY) for the base-case scenario. For patients with LDL-C levels ≥100 mg/dL, the ICER was $839/QALY; for those with diabetes and LDL-C levels ≥70 mg/dL, it was $560/QALY. One-way sensitivity analyses showed that the model was sensitive to changes in cost of ezetimibe, rate reduction of non-fatal CHD, and utility weight for non-fatal CHD in the base-case and sub-group analyses.

LIMITATIONS

Indirect costs or treatment discontinuation estimation were not included.

CONCLUSIONS

Compared with statin monotherapy, ezetimibe with statin therapy was cost-effective for secondary prevention of CHD and stroke and for primary prevention of these conditions in patients whose LDL-C levels are ≥100 mg/dL and in patients with diabetes, taking into account a 90% cost reduction for ezetimibe.

A systematic literature review of methods of incorporating mortality in cost-effectiveness analyses of lipid-lowering therapies

AIMS

Cost effectiveness analysis (CEA) is a useful tool for estimating the value of an intervention in relation to alternatives. In cardiovascular disease (CVD), CEA is especially important, given the high economic and clinical burden. One key driver of value is CVD mortality prevention. However, data used to inform CEA parameters can be limited, given the difficulty in demonstrating statistically significant mortality benefit in randomized clinical trials (RCTs), due in part to the frequency of fatal events and limited trial durations. This systematic review identifies and summarizes whether published CVD-related CEAs have incorporated mortality benefits, and the methodology among those that did.

MATERIALS AND METHODS

A systematic literature review was conducted of CEAs of lipid-lowering therapies published between 2000-2017. Health technology assessments (HTA) and full-length manuscripts were included, and sources of mortality data and methods of applying mortality benefits were extracted. Results were summarized as proportions of articles to articulate common practices in CEAs of CVD.

RESULTS

This review identified 100 studies for inclusion, comprising 93 full-length manuscripts and seven HTA reviews. Among these, 99% assumed a mortality benefit in the model. However, 87 of these studies that incorporated mortality differences did so despite the trials used to inform model parameters not demonstrating statistically significant differences in mortality. None of the 12 studies that used statistically significant findings from an individual RCT were based on active control studies. In a sub-group analysis considering the 60 CEAs that incorporated a direct mortality benefit, 48 (80%) did not have RCT evidence for statistically significant benefit in CVD mortality.

LIMITATIONS AND CONCLUSIONS

The finding that few CEA models included mortality inputs from individual RCTs of lipid-lowering therapy may be surprising, as one might expect that treatment efficacy should be based on robust clinical evidence. However, regulatory requirements in CVD-related RCTs often lead to insufficient sample sizes and observation periods for detecting a difference in CVD mortality, which results in the use of intermediate outcomes, composite end-points, or meta-analysis to extrapolate long-term mortality benefit in a lifetime CEA.

Cost-effectiveness of lanthanum carbonate versus sevelamer hydrochloride for the treatment of hyperphosphatemia in patients with end-stage renal disease: a US payer perspective

OBJECTIVE

To assess the cost-effectiveness of lanthanum carbonate (LC) versus sevelamer hydrochloride (SH) as a treatment for hyperphosphatemia in end-stage renal disease (ESRD) patients.

METHODS

A Markov model was developed to estimate health outcomes; quality-adjusted life years (QALYs) and life-years saved (LYS), as well as associated costs. The model incorporated patient-level data from a randomized head-to-head crossover study that compared the reduction of serum phosphorus using LC and SH for 4 weeks each. The model included patients previously treated with calcium-based binders. Both the intent-to-treat (ITT) population and the cohort of patients who completed treatment in both periods of the study (i.e., completer population) were assessed. The baseline risks of cardiovascular disease (CVD), all-cause mortalities for CVD, and non-CVD patients were derived from a large US renal database. Patient outcomes were modeled for 10 years, and incremental cost-effectiveness ratios (ICERs) were calculated for LC relative to SH. Deterministic and probabilistic sensitivity analyses (PSA) were performed to test the robustness of the base-case model.

RESULTS

For the ITT population, the ICERs of LC versus SH were $24,724/QALY and $15,053/LYS, respectively (in US dollars). When the completer population was considered, the ICERs of LC versus SH were $15,285/QALY and $9,337/LYS (Table 2), respectively. The PSA indicated 61.9% and 85.8% probabilities for ITT and completer populations of LC being cost-effective at the $50,000/QALY willingness-to-pay threshold, respectively.

CONCLUSION

LC is a cost-effective strategy compared with SH in the treatment of ESRD patients with hyperphosphatemia who were previously treated with calcium-based binders. Sensitivity analyses demonstrated the robustness of the pharmacoeconomic model.