Alirocumab versus Evolocumab on Cardiovascular Outcomes: A Systematic Review and Meta-analysis

The PCSK9 enzyme is present mainly in the liver and is responsible for the degradation of LDL-C receptors. Currently, there are some drugs that inhibit this enzyme, such as alirocumab and evolocumab. Consequently, these drugs reduce serum LDL-C levels. Therefore, a systematic review and a meta-analysis were carried out in order to compare alirocumab against evolocumab in reducing cardiovascular outcomes.

This systematic review was carried out in accordance with PRISMA and was registered in PROSPERO (CRD42024573217). The following databases were searched on July, 9, 2024: PubMed, Web of Science and Scopus. Randomized clinical trials with a control group were included and meta-analyses were performed to assess relative risk (RR). The random effects model was used in heterogeneous samples. The articles were distributed into 2 subgroups: use of alirocumab and evolocumab.

Initially, 2,213 articles were found, of which 6 were included. In total, 62,119 patients participated. The RR values were significant for alirocumab in the following outcomes: myocardial infarction (MI) 0.85 (95% CI 0.77-0.93), stroke 0.75 (95% CI 0.60-0.94) and hospitalization for unstable angina 0.58 (95% CI 0.39-0.86), while for evolocumab they were significant for MI 0.75 (95% CI 0.68-0.83) and coronary revascularization 0.81 (95 CI % 0.75-0.88). There was a statistically significant difference between the drugs for hospitalization for unstable angina (p=0.02).

This study highlights the benefits of PCSK9 inhibitors, especially alirocumab, in reducing major cardiovascular events. Alirocumab significantly lowered hospitalizations for unstable angina, with a 42% reduction, and showed favorable outcomes in reducing myocardial infarction, coronary revascularization, and stroke. These reductions are clinically meaningful, as they lower morbidity, improve patient quality of life, and reduce healthcare costs. Both alirocumab and evolocumab are effective and safe, offering important therapeutic options for high-risk cardiovascular patients.

The use of alirocumab is preferable if the focus is to avoid hospitalizations for unstable angina or stroke, while evolocumab may be an option if one wants to avoid coronary revascularization. Both drugs are effective in reducing cardiovascular outcomes, but alirocumab was superior to evolocumab.