PCSK9 Inhibition for Therapeutic Decision-Making

Cost-effectiveness of Icosapent Ethyl for High-risk Patients With Hypertriglyceridemia Despite Statin Treatment

Importance

The Reduction of Cardiovascular Events With Icosapent Ethyl-Intervention Trial (REDUCE-IT) demonstrated the efficacy of icosapent ethyl (IPE) for high-risk patients with hypertriglyceridemia and known cardiovascular disease or diabetes and at least 1 other risk factor who were treated with statins.

Objective

To estimate the cost-effectiveness of IPE compared with standard care for high-risk patients with hypertriglyceridemia despite statin treatment.

Design, Setting, and Participants

An in-trial cost-effectiveness analysis was performed using patient-level study data from REDUCE-IT, and a lifetime analysis was performed using a microsimulation model and data from published literature. The study included 8179 patients with hypertriglyceridemia despite stable statin therapy recruited between November 21, 2011, and May 31, 2018. Analyses were performed from a US health care sector perspective. Statistical analysis was performed from March 1, 2018, to October 31, 2021.

Interventions

Patients were randomly assigned to IPE, 4 g/d, or placebo and were followed up for a median of 4.9 years (IQR, 3.5-5.3 years). The cost of IPE was $4.16 per day after rebates using SSR Health net cost (SSR cost) and $9.28 per day with wholesale acquisition cost (WAC).

Main Outcomes and Measures

Main outcomes were incremental quality-adjusted life-years (QALYs), total direct health care costs (2019 US dollars), and cost-effectiveness.

Results

A total of 4089 patients (2927 men [71.6%]; median age, 64.0 years [IQR, 57.0-69.0 years]) were randomly assigned to receive IPE, and 4090 patients (2895 men [70.8%]; median age, 64.0 years [IQR, 57.0-69.0 years]) were randomly assigned to receive standard care. Treatment with IPE yielded more QALYs than standard care both in trial (3.34 vs 3.27; mean difference, 0.07 [95% CI, 0.01-0.12]) and over a lifetime projection (10.59 vs 10.35; mean difference, 0.24 [95% CI, 0.15-0.33]). In-trial, total health care costs were higher with IPE using either SSR cost ($18 786) or WAC ($24 544) than with standard care ($17 273; mean difference from SSR cost, $1513 [95% CI, $155-$2870]; mean difference from WAC, $7271 [95% CI, $5911-$8630]). Icosapent ethyl cost $22 311 per QALY gained using SSR cost and $107 218 per QALY gained using WAC. Over a lifetime, IPE was projected to be cost saving when using SSR cost ($195 276) compared with standard care ($197 064; mean difference, -$1788 [95% CI, -$9735 to $6159]) but to have higher costs when using WAC ($202 830) compared with standard care (mean difference, $5766 [95% CI, $1094-$10 438]). Compared with standard care, IPE had a 58.4% lifetime probability of costing less and being more effective when using SSR cost and an 89.4% probability of costing less than $50 000 per QALY gained when using SSR cost and a 72.5% probability of costing less than $50 000 per QALY gained when using WAC.

Conclusions and Relevance

This study suggests that, both in-trial and over the lifetime, IPE offers better cardiovascular outcomes than standard care in REDUCE-IT participants at common willingness-to-pay thresholds.

Inclisiran: A Novel Agent for Lowering Apolipoprotein B-Containing Lipoproteins

ABSTRACT

Hypercholesterolemia is a leading cause of cardiovascular morbidity and mortality. Accordingly, efforts to lower apolipoprotein B-containing lipoproteins in plasma are the centerpiece of strategies for cardiovascular prevention and treatment in primary and secondary management. Despite the importance of this endeavor, many patients do not achieve appropriate low density lipoprotein cholesterol (LDL-C) and non-high density lipoprotein cholesterol (non-HDL-C) goals, even among those who have experienced atherosclerotic cardiovascular disease (ASCVD). The development of new LDL-C-lowering medications with alternative mechanisms of action will facilitate improved goal achievement in high risk patients. Inclisiran is a novel small interfering ribonucleic acid (siRNA)-based drug that is experimental in the US and approved for clinical use in the EU. It lowers LDL-C and other apolipoprotein B-containing lipoproteins by reducing production of Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9), a protein that normally contributes to LDL-receptor (LDLR) degradation, thereby increasing LDLR density and recycling in hepatocytes. Although the lipid-lowering efficacy of inclisiran is comparable to results achieved with PCSK9-blocking monoclonal antibodies (PCSK9i) (alirocumab and evolocumab), there are several important differences between the two drug classes. First, inclisiran reduces levels of PCSK9 both intracellularly and extracellularly by blocking translation of and degrading PCSK9 messenger RNA. Second, the long biological half-life of inclisiran produces sustained LDL-C-lowering with twice yearly dosing. Third, although PCSK9i drugs are proven to reduce ASCVD events, clinical outcomes trials with inclisiran are still in progress. In this manuscript, we review the clinical development of inclisiran, its mechanism of action, lipid-lowering efficacy, safety and tolerability, and potential clinical role of this promising new agent.