Supplementary materials: Cost–effectiveness and budget impact analysis of switching from apixaban to rivaroxaban treatment among patients with nonvalvular atrial fibrillation in a German healthcare setting

These are peer-reviewed supplementary materials for the article 'Cost–effectiveness and budget impact analysis of switching from apixaban to rivaroxaban treatment among patients with nonvalvular atrial fibrillation in a German healthcare setting' published in the Journal of Comparative Effectiveness Research.

• Table S1: Summary of key model inputs
• Table S2: Input parameters for baseline clinical event probabilities and clinical event hazard ratios for impact of treatment switch to rivaroxaban
• Table S3: Input parameters for baseline clinical event probabilities and clinical event hazard ratios for impact of treatment discontinuation
• Table S4: Input parameters for baseline clinical event probabilities and clinical event hazard ratios following prior event
• Table S5: Scenario analysis with five-year and ten-year time horizons: Cost-effectiveness analysis results comparing apixaban switchers (to rivaroxaban) versus apixaban continuers
• Table S6: Scenario analysis with no treatment discontinuation: Cost-effectiveness analysis results comparing apixaban switchers (to rivaroxaban) versus apixaban continuers
• Table S7: Annual budget impact of apixaban switchers (to rivaroxaban) versus apixaban continuers over 5 years stratified by cost categories
• Figure S1: Treatment pathway schematic
• Figure S2: Base case deterministic one-way sensitivity analysis: ICER per QALY for apixaban switchers compared with apixaban continuers
• Figure S3: Probabilistic sensitivity analysis scatter plot for apixaban switchers compared with apixaban continuers
• Figure S4: Cost-effectiveness acceptability curve for apixaban switchers compared with apixaban continuers
• References

Aim: Direct oral anticoagulant (DOAC) switching often occurs in patients with nonvalvular atrial fibrillation (NVAF) formedical and nonmedical reasons. Limited data describe the economic consequences of DOAC switching in patients with NVAF. This study evaluates the cost–effectiveness and budget impact of initiating apixaban and switching to rivaroxaban versus initiating and continuing apixaban for patients with NVAF, from a German payer perspective. Materials & methods: Built on an existing model, a cohort-level lifetime Markov model was developed, including dynamic pricing assumptions to account for anticipated generic entry of DOACs. The modeled population (n = 1000) included German patients with NVAF, eligible for oral anticoagulation, who initiated on apixaban. The primary model outcome was the incremental cost–effectiveness ratio, assessed using cost per quality-adjusted life year (QALY) gained and a willingness-to-pay threshold of €48,750/QALY. A secondary model outcome was a 5-year budget impact analysis. Results: Switching patients from apixaban to rivaroxaban led to 285 additional events per 1000 patient years, resulting in 0.079 fewer QALYs and higher total costs per patient (€21,357 vs €16,390 for apixaban continuers). In the base case analysis (with generic pricing assumptions), switching from apixaban to rivaroxaban was dominated (i.e., less effective and more costly) by continuing apixaban. In the budget impact analysis (with generic pricing assumptions), switching from apixaban to rivaroxaban led to additional cumulative costs of €490 per patient over 5 years. Conclusion: Despite the introduction of generic discounting, switching patients with NVAF from apixaban to rivaroxaban led to higher total costs and fewer QALYs under base case assumptions, meaning apixaban switchers were dominated by apixaban continuers from a German payer perspective. Switching patients from apixaban to rivaroxaban also led to greater budget impact over 5 years.