Cost-effectiveness of prasugrel in a US managed care population

The Role of CYP450 Drug Metabolism in Precision Cardio-Oncology

As many novel cancer therapies continue to emerge, the field of Cardio-Oncology (or onco-cardiology) has become crucial to prevent, monitor and treat cancer therapy-related cardiovascular toxicity. Furthermore, given the narrow therapeutic window of most cancer therapies, drug-drug interactions are prevalent in the cancer population. Consequently, there is an increased risk of affecting drug efficacy or predisposing individual patients to adverse side effects. Here we review the role of cytochrome P450 (CYP450) enzymes in the field of Cardio-Oncology. We highlight the importance of cardiac medications in preventive Cardio-Oncology for high-risk patients or in the management of cardiotoxicities during or following cancer treatment. Common interactions between Oncology and Cardiology drugs are catalogued, emphasizing the impact of differential metabolism of each substrate drug on unpredictable drug bioavailability and consequent inter-individual variability in treatment response or development of cardiovascular toxicity. This inter-individual variability in bioavailability and subsequent response can be further enhanced by genomic variants in CYP450, or by modifications of CYP450 gene, RNA or protein expression or function in various 'omics' related to precision medicine. Thus, we advocate for an individualized approach to each patient by a multidisciplinary team with clinical pharmacists evaluating a treatment plan tailored to a practice of precision Cardio-Oncology. This review may increase awareness of these key concepts in the rapidly evolving field of Cardio-Oncology.

Viewpoint: “Underutilisation of novel antiplatelet agents – myths, generics, and economics”

Two oral antiplatelet agents have been recently introduced for acute coronary syndromes indication providing alternatives for dual therapy with aspirin and clopidogrel. In fact, worldwide prasugrel has been on the market for four years, and ticagrelor for over two years. Despite declared benefits over clopidogrel, including hypothetical cost saving advantages, in real life, the clinical utilisation of both agents is small. Generic clopidogrel, and price differences are claimed as major obstacles to prevent broader prasugrel and ticagrelor use. However, these economic difficulties are barely supported by available evidence, and served mostly to protect questionable management spending, as an exuse to explain why in reality cardiologists are so sceptical about both novel agents, and to convince the sharehoders that their money is not wasted, misleading the owners with regard to future success. Importantly, brand Plavix® is used worldwide 5–10 times more often than new agents, despite heavy generic competition. The future of prasugrel outside Japan, where much lower reasonable dose will be used is not impressive due to lack of further outcome studies, negative results of the latest trials, and less than four years left before patent expiration. The fate of ticagrelor will depend on verification of deaths numbers in the ongoing United States Department of Justice PLATO investigation, and confirmation of the mortality benefit in the PEGASUS TIMI-54 trial.

Prasugrel vs. clopidogrel in contemporary Western European patients with acute coronary syndromes receiving drug-eluting stents: Comparative cost-effectiveness analysis from the BASKET-PROVE cohorts

BACKGROUND

Clinical and cost-effectiveness of prasugrel vs. clopidogrel in acute coronary syndrome (ACS) was only evaluated using TRITON-TIMI 38 event rates. A comparative analysis of both drugs in contemporary European ACS patients is lacking.

METHODS

To address this issue, cardiac and bleeding events of 2 "sister" multicenter stent trials, BASKET-PROVE (BP) I with clopidogrel and BPII with prasugrel (for 12months each) were used in a hybrid analysis. Medication costs were 2015 sales prices, event costs modelled for Denmark (DNK), Germany (GER) and Switzerland (SUI) and quality adjusted life years (QALY) by EQ-5D-3L questionnaire.

RESULTS

In BPI and II, 1012 and 985 ACS-patients received drug eluting stents, respectively, followed-up for 2years. Compared to clopidogrel, prasugrel-treated patients had no more major cardiac events (5.2% vs. 6.4%, p=0.422) nor cardiac deaths (1.6% vs. 1.0%, p=0.255), but more major bleedings (4.0% vs. 1.7%, p<0.001) and altogether no difference in QALYs (-0.027 (95%CI: -0.064/0.011)). Prasugrel caused higher total expenditures per patient: 1116.3 (DNK), 1063.5 (GER) and 880.8 (SUI) EURO, respectively. Accordingly, incremental cost-effectiveness was negative for prasugrel vs. clopidogrel with ratios of -45,907 (DNK), -39,909 (GER) and -33,435 (SUI) EURO/QALY gained, making clopidogrel an economically dominant strategy, even after accounting for the non-randomized comparison.

CONCLUSION

Findings of this contemporary European ACS-cohort showed markedly lower cardiac event rates than TRITON-TIMI 38 and no significant difference in 2-year QALYs between prasugrel and clopidogrel-treated patients. At current drug prices, clopidogrel use resulted in an economically dominant treatment strategy in Western European patients.

Contemporary Trends in Oral Antiplatelet Agent Use in Patients Treated with Percutaneous Coronary Intervention for Acute Coronary Syndrome

BACKGROUND

Recent trials demonstrated the efficacy of prasugrel and ticagrelor compared with clopidogrel in the reduction of cardiovascular complications in patients with acute coronary syndrome (ACS). However, it is unclear how use of the 3 antiplatelet medications has changed in commercially insured patients since the advent of the new agents.

OBJECTIVES

To (a) describe the adoption of prasugrel and ticagrelor in patients who received percutaneous coronary intervention (PCI) for the onset of ACS and (b) explore patient factors associated with the selection of the drug to provide insight into utilization patterns of these antiplatelet agents.

METHODS

Patients who received a new dispensing of an antiplatelet agent following a hospitalization for a PCI administered for ACS were identified from insurance claims between 2009 and 2013. Demographics and comorbid conditions were determined based on a 6-month period before the ACS event. Longitudinal trends in antiplatelet agent selection were illustrated using descriptive statistics segmented by month and quarter. Using logistic regressions with stepwise model selection, factors associated with use of the newer medications, as well as with the selection between ticagrelor and prasugrel, were identified.

RESULTS

The analysis included 66,335 subjects. The use of clopidogrel decreased from 100% to roughly 65% of total antiplatelet agent use by the end of 2011 and leveled off thereafter. The introduction of ticagrelor in 2011 coincided with a drop in prasugrel initiation from 35%-18% by December 2013. The use of new agents as opposed to use of clopidogrel was associated with younger age (< 65 years), male gender, and a diagnosis of ST-elevation myocardial infarction. In addition, conditions increasing mortality and risk of cardiovascular complication were associated with higher odds of using clopidogrel. The odds of using ticagrelor over prasugrel increased with older age and history of a cerebrovascular event.

CONCLUSIONS

In 2013, clopidogrel remained the most prescribed agent. Meanwhile, ticagrelor had gradually replaced a substantial portion of prasugrel initiation. Further investigation into outcomes associated with the newer agents, as well as reasons behind the conservative use of the antiplatelet agents, is warranted.

DISCLOSURES

No funding was received for the conduct of this study. DiDomenico received an honorarium from Amgen for the preparation of a heart failure drug monograph for Pharmacy Practice News and was a co-investigator on funded research for the Patient-Centered Outcomes Research Institute. DiDomenico also serves as an advisory board member for a heart failure program at Otsuka America Pharmaceuticals and as an advisory board member at Novartis Pharmaceuticals. Touchette has received unrestricted grant funding from Cardinal Health and Sunovion Pharmaceuticals and has also served as a consultant to and director of the American College of Clinical Pharmacy Practice-Based Research Network on a study funded by Pfizer. None of the authors of this study are involved in financial or personal relationships with agencies, institutions, or organizations that inappropriately influenced the statistical analysis plan or interpretation of the results. Study concept and design were contributed by Kim, Lee, Touchette, and Walton, with assistance from DiDomenico and Ardati. Kim and Lee collected the data, and data interpretation was performed by Lee, DiDomenico, and Ardati, along with Kim and Walton and assisted by Touchette. The manuscript was written by Kim and Walton, with assistance from the other authors, and revised by Kim, Walton, and Lee, with assistance from the other authors.

Prasugrel (Efient®) with percutaneous coronary intervention for treating acute coronary syndromes (review of TA182): systematic review and economic analysis

BACKGROUND

Acute coronary syndromes (ACSs) are life-threatening conditions associated with acute myocardial ischaemia. There are three main types of ACS: ST segment elevation myocardial infarction (STEMI), non-ST segment elevation myocardial infarction (NSTEMI) and unstable angina (UA). One treatment for ACS is percutaneous coronary intervention (PCI) plus adjunctive treatment with antiplatelet drugs. Dual therapy antiplatelet treatment [aspirin plus either prasugrel (Efient(®), Daiichi Sankyo Company Ltd UK/Eli Lilly and Company Ltd), clopidogrel or ticagrelor (Brilique(®), AstraZeneca)] is standard in UK clinical practice. Prasugrel is the focus of this review.

OBJECTIVES

The remit is to appraise the clinical effectiveness and cost-effectiveness of prasugrel within its licensed indication for the treatment of ACS with PCI and is a review of National Institute for Health and Care Excellence technology appraisal TA182.

DATA SOURCES

Four electronic databases (MEDLINE, EMBASE, The Cochrane Library, PubMed) were searched from database inception to June 2013 for randomised controlled trials (RCTs) and to August 2013 for economic evaluations comparing prasugrel with clopidogrel or ticagrelor in ACS patients undergoing PCI.

METHODS

Clinical outcomes included non-fatal and fatal cardiovascular (CV) events, adverse effects of treatment and health-related quality of life (HRQoL). Cost-effectiveness outcomes included incremental cost per life-year gained and incremental cost per quality-adjusted life-year (QALY) gained. An independent economic model assessed four mutually exclusive subgroups: ACS patients treated with PCI for STEMI and with and without diabetes mellitus and ACS patients treated with PCI for UA or NSTEMI and with and without diabetes mellitus.

RESULTS

No new RCTs were identified beyond that reported in TA182. TRITON-TIMI 38 (Trial to Assess Improvement in Therapeutic Outcomes by Optimizing Platelet Inhibition with Prasugrel Thrombolysis in Myocardial Infarction 38) compared prasugrel with clopidogrel in ACS patients scheduled for PCI. No relevant economic evaluations were identified. Our analyses focused on a key subgroup of patients: those aged < 75 years who weighed > 60 kg (no previous stroke or transient ischaemic attack). For the primary composite end point (death from CV causes, non-fatal myocardial infarction or non-fatal stroke) statistically significantly fewer events occurred in the prasugrel arm (8.3%) than in the clopidogrel arm (11%). No statistically significant difference in major bleeding events was noted. However, there was a significant difference in favour of clopidogrel when major and minor bleeding events were combined (3.0 vs. 3.9%). No conclusions could be drawn regarding HRQoL. The results of sensitivity analyses confirmed that it is likely that, for all four ACS subgroups, within 5-10 years prasugrel is a cost-effective treatment option compared with clopidogrel at a willingness-to-pay threshold of £20,000 to £30,000 per QALY gained. At the full 40-year time horizon, all estimates are < £10,000 per QALY gained.

LIMITATIONS

Lack of data precluded a clinical comparison of prasugrel with ticagrelor; the comparative effectiveness of prasugrel compared with ticagrelor therefore remains unknown. The long-term modelling exercise is vulnerable to major assumptions about the continuation of early health outcome gains.

CONCLUSION

A key strength of the review is that it demonstrates the cost-effectiveness of prasugrel compared with clopidogrel using the generic price of clopidogrel. Although the report demonstrates the cost-effectiveness of prasugrel compared with clopidogrel at a threshold of £20,000 to £30,000 per QALY gained, the long-term modelling is vulnerable to major assumptions regarding long-term gains. Lack of data precluded a clinical comparison of prasugrel with ticagrelor; the comparative effectiveness of prasugrel compared with ticagrelor therefore remains unknown. Well-audited data are needed from a long-term UK clinical registry on defined ACS patient groups treated with PCI who receive prasugrel, ticagrelor and clopidogrel.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013005047.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Economic outcomes with prasugrel versus clopidogrel in acute coronary syndrome patients: observations from prasugrel users and matched clopidogrel users

OBJECTIVE

To compare healthcare costs between clopidogrel and prasugrel over 30-day and 365-day periods after discharge from the hospital or emergency room (ER) in patients treated with prasugrel who were hospitalized or had an ER visit for an acute coronary syndrome (ACS) event.

METHODS

This retrospective observational study was based on claims from January 2009-July 2012 in the Truven Health Analytics MarketScan database. Clopidogrel patients were propensity-score matched 1:1 to prasugrel-treated patients. Lin's frequentist cost history method for censored data and Bayesian zero-inflated gamma regression models were used to analyze healthcare costs.

RESULTS

The clopidogrel/prasugrel matched-cohort included 10,963 well-matched pairs of patients. Lin's frequentist analysis showed that outpatient visit costs were significantly lower for clopidogrel than prasugrel after 30 days of follow-up. At 30 days, Bayesian data analysis showed strong evidence that clopidogrel was superior to prasugrel for all-cause and ACS-related hospitalization costs and showed very strong evidence that clopidogrel was superior to prasugrel for all-cause and ACS-related outpatient visit costs. At 365 days, Bayesian data analysis showed strong evidence that clopidogrel was superior to prasugrel for all-cause outpatient visit costs and very strong evidence that clopidogrel was superior to prasugrel for ACS-related outpatient visit costs. Point estimates of the all-cause and ACS-related ER visit costs at 30 days and 365 days were similar, but statistical results were inconclusive because of the large variability in this outcome variable.

CONCLUSION

Based on retrospective observational data in a real-world setting, all-cause and ACS-related hospitalization and outpatient visit costs were lower for clopidogrel than prasugrel over 30 days after discharge from a hospitalization or ER visit associated with ACS in patients treated with prasugrel. At 365 days the difference in all-cause and ACS-related outpatient costs remained, but there was little evidence of a difference in either all-cause or ACS-related hospitalization costs.

Cost effectiveness of treatments for non-ST-segment elevation acute coronary syndrome

BACKGROUND

Acute coronary syndrome (ACS) represents the most common subset of cardiovascular heart diseases and relates to high rates of morbidity and mortality worldwide and, consequently, to both the direct and indirect costs to the health system and society. Given the rising healthcare costs combined with budgetary constraints, health care systems and decision makers are faced with challenging decisions and the need to choose alternative treatments that not only improve patient quantity and quality of life but are also economically attractive.

OBJECTIVES

To systematically review the published literature and to identify studies evaluating the cost effectiveness of different treatments for patients presenting with non-ST-segment elevation (NSTE) ACS.

DATA SOURCES

A literature search was performed using PubMed and the Cochrane Library until October 2013, with no limit on publication date.

STUDY SELECTION

The search was conducted using predetermined inclusion and exclusion criteria, limiting articles to those published in the English language and those reporting results of economic evaluations [i.e. cost-effectiveness (CEA), cost-utility (CUA) cost-minimisation (CMA) cost-consequence (CCA) and cost-benefit (CBA) analyses] of the different treatment therapies used for managing patients presenting with NSTE-ACS. Publications such as editorials, letters to the editor, posters, expert opinions, reviews, systematic reviews, or meta-analyses were excluded.

STUDY APPRAISAL METHODS

All studies included were assessed for their methodological quality using the British Medical Journal checklist.

RESULTS

A total of 39 studies were included, presenting a wide variation in terms of methodological approaches and settings, thus resulting in different ranges of incremental cost-effectiveness ratios for each treatment evaluated.

CONCLUSIONS

Evidence from the present systematic review suggests that the majority of the available treatments represent either cost-saving or cost-effective options for NSTE-ACS patients. Moreover, the cost effectiveness of the available treatments was found to be dependent on various factors, particularly the risk profile of patients and the cost of treatment, and hence there is a need to take these into consideration when making decisions and choices.

Cost-utility analysis of genotype-guided antiplatelet therapy in patients with moderate-to-high risk acute coronary syndrome and planned percutaneous coronary intervention

BACKGROUND

Prasugrel is recommended over clopidogrel in poor/intermediate CYP2C19 metabolizers with acute coronary syndrome (ACS) and planned percutaneous coronary intervention (PCI), reducing the risk of ischemic events. CYP2C19 genetic testing can guide antiplatelet therapy in ACS patients.

OBJECTIVE

The purpose of this study was to evaluate the cost-utility of genotype-guided treatment, compared with prasugrel or generic clopidogrel treatment without genotyping, from the US healthcare provider's perspective.

METHODS

A decision model was developed to project lifetime economic and humanistic burden associated with clinical outcomes (myocardial infarction [MI], stroke and major bleeding) for the three strategies in patients with ACS. Probabilities, costs and age-adjusted quality of life were identified through systematic literature review. Incremental cost-utility ratios (ICURs) were calculated for the treatment strategies, with quality-adjusted life years (QALYs) as the primary effectiveness outcome. Relative risk of developing myocardial infarction and stroke between patients with and without variant CYP2C19 when receiving clopidogrel were estimated to be 1.34 and 3.66, respectively. One-way and probabilistic sensitivity analyses were performed.

RESULTS

Clopidogrel cost USD19,147 and provided 10.03 QALYs versus prasugrel (USD21,425, 10.04 QALYs) and genotype-guided therapy (USD19,231, 10.05 QALYs). The ICUR of genotype-guided therapy compared with clopidogrel was USD4,200. Genotype-guided therapy provided more QALYs at lower costs compared with prasugrel. Results were sensitive to the cost of clopidogrel and relative risk of myocardial infarction and stroke between CYP2C19 variant vs. non-variant. Net monetary benefit curves showed that genotype-guided therapy had at least 70% likelihood of being the most cost-effective alternative at a willingness-to-pay of USD100,000/QALY. In comparison with clopidogrel, prasugrel therapy was more cost-effective with <21% certainty at willingness-to-pay of >USD170,000/QALY.

CONCLUSIONS

Our modeling analyses suggest that genotype-guided therapy is a cost-effective strategy in patients with acute coronary syndrome undergoing planned percutaneous coronary intervention.

A systematic review of the quality of economic models comparing thrombosis inhibitors in patients with acute coronary syndrome undergoing percutaneous coronary intervention

BACKGROUND

Thrombosis inhibitors can be used to treat acute coronary syndromes (ACS). However, there are various alternative treatment strategies, of which some have been compared using health economic decision models.

OBJECTIVE

To assess the quality of health economic decision models comparing thrombosis inhibitors in patients with ACS undergoing percutaneous coronary intervention, and to identify areas for quality improvement.

DATA SOURCES

The literature databases MEDLINE, EMBASE, EconLit, National Health Service Economic Evaluation Database (NHS EED), Database of Abstracts of Reviews of Effects (DARE) and Health Technology Assessment (HTA).

STUDY APPRAISAL AND SYNTHESIS METHODS

A review of the quality of health economic decision models was conducted by two independent reviewers, using the Philips checklist.

RESULTS

Twenty-one relevant studies were identified. Differences were apparent regarding the model type (six decision trees, four Markov models, eight combinations, three undefined models), the model structure (types of events, Markov states) and the incorporation of data (efficacy, cost and utility data). Critical issues were the absence of particular events (e.g. thrombocytopenia, stroke) and questionable usage of utility values within some studies.

LIMITATIONS

As we restricted our search to health economic decision models comparing thrombosis inhibitors, interesting aspects related to the quality of studies of adjacent medical areas that compared stents or procedures could have been missed.

CONCLUSIONS

This review identified areas where recommendations are indicated regarding the quality of future ACS decision models. For example, all critical events and relevant treatment options should be included. Models also need to allow for changing event probabilities to correctly reflect ACS and to incorporate appropriate, age-specific utility values and decrements when conducting cost-utility analyses.

Antiplatelet therapy in patients undergoing percutaneous coronary intervention: economic considerations

Percutaneous coronary intervention (PCI) is one of the most common medical procedures performed for treatment of coronary artery disease. Antiplatelet medications as adjunctive therapy for PCI are used routinely, with indications for specific agents or their combinations varying depending on the clinical scenario. While the cost-effectiveness of well-established agents has been extensively studied, newer drugs have not been evaluated as thoroughly. In addition, the clinical application of some antiplatelet drugs has recently changed, thus making older studies of cost effectiveness less applicable to the current landscape of clinical practice. This article reviews cost-effectiveness considerations of antiplatelet therapies in the treatment of coronary artery disease in patients undergoing PCI. Aspirin, P2Y12 inhibitors including clopidogrel and the newer agents prasugrel and ticagrelor, as well as glycoprotein (GP) IIb/IIIa inhibitors, are discussed. Overall, the use of dual antiplatelet therapy with aspirin and a P2Y12 inhibitor in patients undergoing PCI improves ischaemic outcomes and appears to be cost effective. The few available studies suggest that the recently approved medications prasugrel and ticagrelor are cost-effective alternatives to clopidogrel. However, no direct comparison between these two newer agents is available. The indications for GP IIb/IIIa inhibitors have changed in the current PCI era, and there is a paucity of cost-effectiveness data for their use in contemporary care.

Clopidogrel, prasugrel, or ticagrelor? a practical guide to use of antiplatelet agents in patients with acute coronary syndromes

Aspirin is a cornerstone of therapy in the treatment of patients with acute coronary syndromes (ACS). However, dual antiplatelet therapy reduces the risk of stent thrombosis and cardiovascular events compared with aspirin alone in the treatment of patients with ACS. Recently, there has been debate as to which antiplatelet agent should be added to aspirin in the ACS treatment regimen. This review summarizes the pharmacologic and clinical data comparing clopidogrel, prasugrel, and ticagrelor, and provides a practical guide to clinicians for determining which antiplatelet to use for patients with ACS.

Prasugrel vs clopidogrel in patients with acute coronary syndrome undergoing percutaneous coronary intervention: a model-based cost-effectiveness analysis for Germany, Sweden, the Netherlands, and Turkey

OBJECTIVE

To evaluate the long-term cost-effectiveness of 12-months treatment with prasugrel vs clopidogrel from four European healthcare systems' perspectives (Germany, Sweden, the Netherlands, and Turkey).

METHODS

In the TRITON-TIMI 38 trial, patients with an acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI) were treated with prasugrel or clopidogrel. Prasugrel reduced the composite end-point (cardiovascular death, MI, or stroke), but increased TIMI major bleeding. A Markov model was constructed to facilitate a lifetime horizon for the analysis. A series of risk equations constructed using individual patient data from TRITON-TIMI 38 was used to estimate risks of clinical events. Quality-adjusted life-years (QALYs) were derived by weighting survival time by estimates of health-related quality-of-life. Incremental cost-effectiveness is presented based on differences in treatments' mean costs and QALYs for the licensed population in TRITON-TIMI 38, and the sub-groups of UA-NSTEMI, STEMI, diabetes, and the 'core clinical cohort' (<75 years, ≥60 kg, no history of stroke or TIA).

RESULTS

Mean cost of study drug was €364 (Turkey) to €818 (Germany) higher for prasugrel vs clopidogrel. Rehospitalization costs at 12 months were lower for prasugrel due to reduced rates of revascularization, although hospitalization costs beyond 12 months were higher due to longer life expectancy associated with lower rates of non-fatal MI in the prasugrel group. The incremental cost per QALY saved with prasugrel in the licensed population ranged from €6520 (for Sweden) to €14,350 for (Germany). Prasugrel's cost per QALY was more favourable still in the STEMI and diabetes sub-groups of the licensed population.

LIMITATIONS

Probabilistic analyses of the whole trial population is impractical due to the number of individual patient profiles over which population level results are calculated.

CONCLUSION

Among patients undergoing PCI for ACS, treatment with prasugrel compared with clopidogrel resulted in favourable cost-effectiveness profiles from these healthcare systems' perspectives.