Cost-effectiveness of Dabigatran Compared With Rivaroxaban for Prevention of Stroke and Systemic Embolism in Patients With Atrial Fibrillation in China

Methods for Economic Evaluations of Novel Oral Anticoagulants in Patients with Atrial Fibrillation: A Systematic Review

BACKGROUND

Atrial fibrillation (AF) is a severe epidemiological and public health concern among the elderly population worldwide, with substantial economic and social burdens. Economic evaluations can play an essential role in optimizing the utilization of scarce resources. In recent years, the number of economic evaluation studies related to AF has increased due to the rising number of AF patients, the continuous updating of clinical data, and the emergence of real-world evidence. However, there are still deficiencies in model settings and parameter sources in relevant studies.

OBJECTIVE

This study aims to review the existing economic evaluations of novel oral anticoagulants (NOACs) in patients with AF and summarize the evidence and methods applied.

METHODS

A comprehensive and systematic search was conducted on electronic databases, including PubMed, Embase, Web of Science (WOS), and The Cochrane Library, from the date of database creation to November 2022. The reporting quality of included literature was assessed using the Consolidated Health Economic Evaluation Reporting Standards 2022 (CHEERS 2022) statement.

RESULTS

A total of 102 studies were included in the review, with 200 comparisons between NOACs and vitamin K antagonists (VKAs), as well as 58 comparisons between different NOACs. The healthcare sector and payer perspectives were the most common, and accordingly, the majority of the evaluations considered only direct medical costs. Most studies used Markov cohort models with the number of health states ranging from 4 to 29. Of included studies, 80 (78%) considered event recurrence and complications, and 78 (76%) considered discontinuation and second-line therapy. All of the studies applied uncertainty analysis to explore the robustness of the results. Of all 200 NOACs-VKAs comparisons, 149 (75%) showed that NOACs were more cost-effective; this proportion was 84% (139 out of 165) in high-income countries but decreased to 29% (10 out of 35) in middle- and low-income countries. Most (82%) of the 28 items in the CHEERS 2022 checklist were elucidated in the majority of included studies. A minority (only 39%) of included studies demonstrated high reporting quality.

CONCLUSION

NOACs may be more cost-effective than VKAs in patients with AF, but this conclusion applies to high-income countries, whereas VKAs may be more cost-effective in middle- and low-income countries. The reporting quality of included studies was variable, and certain methodological issues were presented. This study highlights the economic evaluation methodology of NOACs in patients with AF and provides recommendations for modeling methods and future studies.

Budget and health impact of switching eligible patients with atrial fibrillation to lower- dose dabigatran

Objectives: To assess the comparative budget and health impact of lower-dose dabigatran versus reduced doses of apixaban and rivaroxaban in atrial fibrillation (AF) patients eligible for a lower-/reduced-dose due to individual patient characteristics in the Netherlands. Methods: A budget impact model was developed in accordance with ISPOR guidelines. A 3-year-time horizon was considered, and analyses were conducted from a Dutch healthcare payer's perspective. The model applies published data to local AF-epidemiology, allowing calculations to estimate clinical events (strokes and haemorrhages) and costs. The analyses were based on real-world outcomes from patients with AF receiving a first direct oral anticoagulant (DOAC) prescription for low-dose dabigatran (110 mg) and a reduced dose of apixaban (2.5 mg) or rivaroxaban (15 mg). Two situations of switching treatments from one to another DOAC were modelled: switching from apixaban to dabigatran and from rivaroxaban to dabigatran. Base case results were given as savings per 100 patient-year, per total Dutch population, and events avoided. A univariate sensitivity analysis was conducted to explore the uncertainty around epidemiological and event costs input data. Scenario analyses were performed to estimate the effect of different market shares and potential price reductions due to future patent expiry for the total real-world population from the Netherlands. Results: The 3-years outcomes of switching patients eligible for a lower-/reduced-dose due to individual patient characteristics from apixaban or rivaroxaban to dabigatran resulted in cost savings estimated at €157 or €72 thousand per 100 patient-years, respectively, or €146 million per total Dutch population. Looking into the clinical events, dabigatran reflected the lowest number of mortalities, ischemic strokes, major bleeding, non-major bleeding, and haemorrhagic stroke compared to apixaban and rivaroxaban. The sensitivity analysis consistently reflected cost savings, with the ischeamic stroke events having the biggest impact. Accounting for the Dutch situation, both scenarios showed total savings ranging from €45 to €229 million over 3 years. Conclusions: Switching eligible AF-patients from reduced-dose apixaban or rivaroxaban to lower-dose dabigatran has the potential to reduce healthcare payer's budget expenditures and provide health gains. Cost savings can potentially be further enhanced by market share adjustments and further price reductions.

Cost-Effectiveness Analysis of Rivaroxaban in Chinese Patients With Stable Cardiovascular Disease

Objective: This study aimed to investigate the cost-effectiveness of low-dose rivaroxaban plus aspirin versus aspirin alone for patients with stable cardiovascular diseases in the China.

Methods: We used TreeAge 2019 to construct a Markov model to assess the direct healthcare costs and quality-adjusted life years for three therapies, namely low-does rivaroxaban plus aspirin, rivaroxaban alone, and aspirin alone. Transitional probabilities were derived from the COMPASS trial, and the costs and utilities were obtained from the Chinese Health Care Statistical Yearbook and published studies. Use the Incremental cost-effectiveness ratio to describe the results. The willingness-to-pay threshold is set at US$11,000 (China’s 2020 Gross National Product per capita).

Result: In patients with stable cardiovascular disease, the increased cost per quality-adjusted life year gained in the low-dose rivaroxaban combined with aspirin group compared to the aspirin alone group was US$7937.30. The increased cost per quality-adjusted life year gained in the rivaroxaban alone group versus the aspirin alone group was US$15,045.78.

Conclusion: A low-does rivaroxaban plus aspirin therapy may be cost-effective in the secondary prevention of stable cardiovascular disease in patients.

Long-Term Cost-Effectiveness Comparison of Catheter Ablation and Antiarrhythmic Drugs in Atrial Fibrillation Treatment Using Discrete Event Simulation

OBJECTIVES

To evaluate the lifetime cost-effectiveness of 3 widely used atrial fibrillation (AF) treatments from the perspectives of Chinese healthcare system: antiarrhythmic drugs (AADs), ThermoCool SmartTouch guided by ablation index (STAI), and second-generation cryoballoon (CB2).

METHODS

A discrete event simulation (DES) model was implemented to compare the lifetime cost-effectiveness of AADs, STAI, and CB2. AF disease progression was explicitly modeled based on the Atrial Fibrillation Progression Trial clinical study results. The base-case analysis assumed that patients with paroxysmal AF (PAF) entered the model at the age of 55 years and had a CHA2DS2-VASc (Congestive heart failure, Hypertension, Age ( > 65 = 1 point, > 75 = 2 points), Diabetes, previous Stroke/transient ischemic attack (2 points)-Vascular disease (peripheral arterial disease, previous myocardial infarction, aortic atheroma), Age 65 to 74 years, and Sex category) score of 2 for males and 3 for females. Model parameter uncertainties were incorporated throughout the DES simulation with full probabilistic model parameterization.

RESULTS

The lifetime cost-effectiveness evaluations showed that patients treated with AADs gained an average of 4.98 quality-adjusted life-years (QALYs) and 9.63 life-years (LYs) at an average cost of US dollar (USD) 15 374. Patients treated with CB2 gained 5.92 QALYs and 10.74 LYs at an average cost of USD 26 811. The STAI group gained an average of 6.55 QALYs and 11.57 LYs at an average cost of USD 24 722. The incremental cost-effectiveness ratios was USD 5927 and USD 12 167 per QALY for STAI versus AADs and CB2 versus AADs, respectively. Assuming the willingness-to-pay threshold for China is USD 30 390 per QALY, both ablation treatments will be cost-effective compared with AADs for patients with PAF.

CONCLUSIONS

The DES model demonstrated that catheter ablations are more cost-effective than AADs for patients with PAF under the healthcare system in China. Among catheter ablation technologies, STAI provides better outcomes at lower costs.