Cost-effectiveness of Evolocumab Therapy for Reducing Cardiovascular Events in Patients With Atherosclerotic Cardiovascular Disease

Abstract

Importance: The proprotein convertase subtilisin/kexin type 9 inhibitor evolocumab has been demonstrated to reduce the composite of myocardial infarction, stroke, or cardiovascular death in patients with established atherosclerotic cardiovascular disease. To our knowledge, long-term cost-effectiveness of this therapy has not been evaluated using clinical trial efficacy data.

Objective: To evaluate the cost-effectiveness of evolocumab in patients with atherosclerotic cardiovascular disease when added to standard background therapy.

Design, setting, and participants: A Markov cohort state-transition model was used, integrating US population-specific demographics, risk factors, background therapy, and event rates along with trial-based event risk reduction. Costs, including price of drug, utilities, and transitional probabilities, were included from published sources.

Exposures: Addition of evolocumab to standard background therapy including statins.

Main outcomes and measures: Cardiovascular events including myocardial infarction, ischemic stroke and cardiovascular death, quality-adjusted life-year (QALY), incremental cost-effectiveness ratio (ICER), and net value-based price.

Results: In the base case, using US clinical practice patients with atherosclerotic cardiovascular disease with low-density lipoprotein cholesterol levels of at least 70 mg/dL (to convert to millimoles per liter, multiply by 0.0259) and an annual events rate of 6.4 per 100 patient-years, evolocumab was associated with increased cost and improved QALY: incremental cost, $105 398; incremental QALY, 0.39, with an ICER of $268 637 per QALY gained ($165 689 with discounted price of $10 311 based on mean rebate of 29% for branded pharmaceuticals). Sensitivity and scenario analyses demonstrated ICERs ranging from $100 193 to $488 642 per QALY, with ICER of $413 579 per QALY for trial patient characteristics and event rate of 4.2 per 100 patient-years ($270 192 with discounted price of $10 311) and $483 800 if no cardiovascular mortality reduction emerges. Evolocumab treatment exceeded $150 000 per QALY in most scenarios but would meet this threshold at an annual net price of $9669 ($6780 for the trial participants) or with the discounted net price of $10 311 in patients with low-density lipoprotein cholesterol levels of at least 80 mg/dL.

Conclusions and relevance: At its current list price of $14 523, the addition of evolocumab to standard background therapy in patients with atherosclerotic cardiovascular disease exceeds generally accepted cost-effectiveness thresholds. To achieve an ICER of $150 000 per QALY, the annual net price would need to be substantially lower ($9669 for US clinical practice and $6780 for trial participants), or a higher-risk population would need to be treated.

Figure.. Incremental Cost-effectiveness Ratios and Value-Based Pricing by Annual Cardiovascular Event Rates

A, Incremental cost-effectiveness ratio (ICER) values for a range of annual cardiovascular event rates per 100 patient-years using full list price ($14 523 per year) and discounted net price ($10 311 per year) for evolocumab for the US clinical practice population. Annual cardiovascular event rate per 100 patient-years integrates multiple events into the rates (patients may experience more than 1 event). B, ICER values for a range of annual cardiovascular event rates per 100 patient-years using full list price ($14 523 per year) and discounted net price ($10 311 per year) for evolocumab for the FOURIER trial population. C, Value-based prices (VBPs) at range of annual cardiovascular event rates per 100 patient-years for the US clinical practice population and for the FOURIER trial participants.