Primary Risk Drivers
Below is a snapshot of domains that materially influence the MARA Rating.
Clinical effectiveness
The evidence from the ARISTOTLE trial demonstrated that apixaban was non-inferior to warfarin for the primary outcome of stroke and systemic embolism, with a significant reduction in the rate of fatal or disabling strokes (HR 0.71, 95% CI 0.54 to 0.94). Although the trial did not show statistically significant superiority for all individual components, the overall clinical benefit is clear, particularly in reducing hemorrhagic strokes.
Cost effectiveness
The ICER for apixaban compared to warfarin was reported at £11,008 per QALY gained, which is well within acceptable thresholds. The probabilistic sensitivity analysis indicated an 80% probability of being cost-effective at £20,000 per QALY, supporting its economic value.
Quality of life
While the document indicates that apixaban may improve quality of life compared to warfarin, it lacks direct evidence from HRQoL assessments in the trials. The absence of specific data on health-related quality of life outcomes limits the ability to assign a higher rating.
Supporting Domains
Safety and Adverse Effects
Apixaban demonstrated a significantly lower rate of major bleeding events compared to warfarin, particularly intracranial bleeding (HR 0.42, 95% CI 0.30 to 0.58). The overall safety profile appears favorable, with fewer adverse events reported.
Comparator Selection
The primary evidence comes from the ARISTOTLE trial comparing apixaban with warfarin, which is appropriate. However, the lack of direct head-to-head comparisons with other newer anticoagulants like dabigatran and rivaroxaban limits the robustness of the evidence.
Patient Population and Subgroups
The ARISTOTLE trial included a diverse population with a mean CHADS2 score of 2.1, which is representative of the UK population. However, subgroup analyses were not statistically powered to demonstrate superiority, which introduces some limitations.
Care Pathway Integration
Apixaban can be integrated into existing care pathways with minimal disruption, as it does not require new infrastructure or extensive training for healthcare providers. The transition from warfarin to apixaban is straightforward.
Resource Use and Cost Implications
The economic model indicates that apixaban is cost-effective with manageable budget impacts. The annual cost of apixaban is £803, which is justified by the clinical benefits and cost-effectiveness demonstrated in the analysis.
Evidence Quality and Robustness
The evidence is based on high-quality RCTs (ARISTOTLE and AVERROES) with low risk of bias. The robustness of the findings is supported by the consistency of results across various analyses, although some limitations in subgroup analyses exist.
Uncertainty, Sensitivity, and Broader Impacts
While there are some uncertainties regarding the long-term outcomes and the generalizability of trial results, the overall context supports the use of apixaban, particularly given the unmet need in the target population.
