Effect of alirocumab and evolocumab on all-cause mortality and major cardiovascular events: A meta-analysis focusing on the number needed to treat

Effects of PCSK9 inhibitors on cancer, diabetes, and cardiovascular diseases

Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) have potential applications in cancer therapy and as cholesterol-lowering treatments. The impact of PCSK9 suppression on both tumor growth and metastasis, as well as the management of diabetes, has been demonstrated. PCSK9i can also enhance outcomes and reduce cardiovascular (CV) events in individuals with a history of such events. In this review, we provide insights into the pharmacology, safety, and impact of PCSK9i. We highlight cutting-edge investigations, the development of innovative PCSK9i-based products, and a more comprehensive understanding of the potential effects of these drugs on cancer, diabetes, and CV and cerebrovascular diseases.

Association of PCSK9 inhibitors with mortality: insights from a retrospective cohort analysis

AIMS

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are effective in reducing cardiovascular events, but their impact on all-cause mortality and medical utilization compared to statins is unclear. This study investigated PCSK9 inhibitor use and its impact on mortality and medical utilization vs. statins, using TriNetX database data with up to 9 years of follow-up.

METHODS AND RESULTS

This retrospective cohort study analysed TriNetX data spanning 1 July 2015, to 31 December 2023, including 79 194 PCSK9 inhibitor users (alirocumab, evolocumab, inclisiran) and 5 437 513 statin users with hyperlipidaemia. The primary outcomes were all-cause mortality and medical utilization, including hospital inpatient services, emergency department visits, critical care, and mechanical ventilation. Propensity score matching showed that PCSK9 inhibitor use was associated with a 28.3% lower risk of all-cause mortality [adjusted hazard ratio (aHR) 0.717, 95% confidence interval (CI): 0.673-0.763] and significant reductions in medical utilization (hospital inpatient services usage: aHR 0.692, 95% CI: 0.664-0.721; emergency department services: aHR 0.756, 95% CI: 0.726-0.788; critical care services: aHR 0.619, 95% CI: 0.578-0.664; and mechanical ventilation: aHR 0.537, 95% CI: 0.484-0.596) compared to statins. These findings were consistent across various demographics and clinical subgroups. The sensitivity analyses supported the robustness of the findings.

CONCLUSION

PCSK9 inhibitors significantly reduced all-cause mortality and medical utilization compared to statins, suggesting their important role in dyslipidaemia management, particularly for statin-naïve or intolerant patients. Further research, including randomized controlled trials, is needed to confirm these findings and explore the underlying mechanisms.

Early administration of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors in patients with acute coronary syndrome: a systematic review and meta-analysis

BACKGROUND

High-intensity statin therapy is currently recommended initial guideline therapy in ACS treatment. However, only a minority of patients are achieving LDL-C attainment goal at 6 months. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are on recommended guideline therapy post-ACS if LDL-C goal attainment is not achieved after high-intensity statin (4-6 weeks) and after the addition of ezetimibe if guideline goal attainment is not achieved after an additional 4-6 weeks. Thus, it has been recommended that PCSK9 inhibitors be considered earlier post-ACS. However, the efficacy of early PCSK9 inhibitors initiation in ACS patients remains uncertain.

METHODS

This systematic review and meta-analysis was conducted following PRISMA guidelines. Randomized controlled trials (RCTs) and observational studies involving ACS patients who received PCSK9 inhibitors within 48 h of hospitalization were included. Common and random effects models were used to evaluate the pooled effect of early PCSK9 inhibitor administration. Nine RCTs and three cohort studies were included.

RESULTS

Early PCSK9 inhibitor administration reduced the incidence of MI, ACS hospitalization, and revascularization at 6-18 months post-ACS. Although there was a drift towards reduced stroke, all-cause mortality, and cardiovascular death, no statistically significant reduction was observed. Additionally, PCSK9 inhibitors significantly enhanced lipid control at 4-12 weeks after index hospitalization.

CONCLUSION

Early PCSK9 inhibitors initiation in ACS patients reduces MACE and improves lipid profiles. While the results propose promising benefits in terms of stroke and mortality, further research with longer follow-up is required for more decisive evidence.

Persistence and Adherence to PCSK9 Inhibitor Monoclonal Antibodies Versus Ezetimibe in Real-World Settings

INTRODUCTION

The cardiovascular disease risk reduction benefits of proprotein convertase subtilisin/kexin type 9 inhibitor monoclonal antibodies (PCSK9i mAb) and ezetimibe are dependent on remaining on treatment and being persistent and adherent. We estimated the percentage of patients on therapy, persistent and adherent at 182 and 365 days among US adults with health insurance who initiated a PCSK9i mAb (n = 16,588) or ezetimibe (n = 83,086) between July 2015 and December 2019.

METHODS

Using pharmacy fill claims, being on therapy was defined as having a day of medication supply in the last 60 of 182 and 365 days following treatment initiation, being persistent was defined as not having a gap of 60 days or more between the last day of supply from one prescription fill and the next fill, and being adherent was defined by having medication available to take on ≥ 80% of the 182 and 365 days following treatment initiation. We estimated multivariable-adjusted risk ratios for being persistent and adherent comparing patients initiating PCSK9i mAb versus ezetimibe using Poisson regression.

RESULTS

At 182 days following initiation, 80% and 68% were on therapy and 76% and 64% were persistent among patients who initiated a PCSK9i mAb and ezetimibe, respectively. Among patients who were on therapy and persistent at 182 days following initiation, 88% and 81% of those who initiated a PCSK9i mAb and ezetimibe, respectively, were on therapy at 365 days. Among those on therapy and persistent at 182 days following initiation, being persistent and being adherent at 365 days were each more common among PCSK9i mAb versus ezetimibe initiators (persistent: 82% versus 76%, multivariable-adjusted risk ratio 1.07; 95% confidence interval [CI] 1.06-1.08; adherent: 74% versus 71%, multivariable-adjusted risk ratio 1.02; 95% CI 1.01-1.03).

CONCLUSIONS

These data suggest approaches to increase persistence and adherence to PCSK9i mAb and ezetimibe should be implemented prior to or within 182 days following treatment initiation.

Targeting the ACOD1-itaconate axis stabilizes atherosclerotic plaques

Inflammatory macrophages are key drivers of atherosclerosis that can induce rupture-prone vulnerable plaques. Skewing the plaque macrophage population towards a more protective phenotype and reducing the occurrence of clinical events is thought to be a promising method of treating atherosclerotic patients. In the current study, we investigate the immunomodulatory properties of itaconate, an immunometabolite derived from the TCA cycle intermediate cis-aconitate and synthesised by the enzyme Aconitate Decarboxylase 1 (ACOD1, also known as IRG1), in the context of atherosclerosis. Ldlr-/- atherogenic mice transplanted with Acod1-/- bone marrow displayed a more stable plaque phenotype with smaller necrotic cores and showed increased recruitment of monocytes to the vessel intima. Macrophages from Acod1-/- mice contained more lipids whilst also displaying reduced induction of apoptosis. Using multi-omics approaches, we identify a metabolic shift towards purine metabolism, in addition to an altered glycolytic flux towards production of glycerol for triglyceride synthesis. Overall, our data highlight the potential of therapeutically blocking ACOD1 with the aim of stabilizing atherosclerotic plaques.

Proprotein convertase subtilisn/kexin type 9 inhibitors and small interfering RNA therapy for cardiovascular risk reduction: A systematic review and meta-analysis

BACKGROUND

Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of mortality worldwide. Atherosclerosis occurs due to accumulation of low-density lipoprotein cholesterol (LDL-c) in the arterial system. Thus, lipid lowering therapy is essential for both primary and secondary prevention. Proprotein convertase subtilisn/kexin type 9 (PCSK9) inhibitors (Evolocumab, Alirocumab) and small interfering RNA (siRNA) therapy (Inclisiran) have been demonstrated to lower LDL-c and ASCVD events in conjunction with maximally tolerated statin therapy. However, the degree of LDL-c reduction and the impact on reducing major adverse cardiac events, including their impact on mortality, remains unclear.

OBJECTIVE

The purpose of this study is to examine the effects of PCSK9 inhibitors and small interfering RNA (siRNA) therapy on LDL-c reduction and major adverse cardiac events (MACE) and mortality by conducting a meta-analysis of randomized controlled trials.

METHODS

Using Pubmed, Embase, Cochrane Library and clinicaltrials.gov until April 2023, we extracted randomized controlled trials (RCTs) of PCSK9 inhibitors (Evolocumab, Alirocumab) and siRNA therapy (Inclisiran) for lipid lowering and risk of MACE. Using random-effects models, we pooled the relative risks and 95% CIs and weighted least-squares mean difference in LDL-c levels. We estimated odds ratios with 95% CIs among MACE subtypes and all-cause mortality. Fixed-effect model was used, and heterogeneity was assessed using the I2 statistic.

RESULTS

In all, 54 studies with 87,669 participants (142,262 person-years) met criteria for inclusion. LDL-c percent change was reported in 47 studies (n = 62,634) evaluating two PCSK9 inhibitors and siRNA therapy. Of those, 21 studies (n = 41,361) included treatment with Evolocumab (140mg), 22 (n = 11,751) included Alirocumab (75mg), and 4 studies (n = 9,522) included Inclisiran (284mg and 300mg). Compared with placebo, after a median of 24 weeks (IQR 12-52), Evolocumab reduced LDL-c by -61.09% (95% CI: -64.81, -57.38, p<0.01) and Alirocumab reduced LDL-c by -46.35% (95% CI: -51.75, -41.13, p<0.01). Inclisiran 284mg reduced LDL-c by -54.83% (95% CI: -59.04, -50.62, p = 0.05) and Inclisiran 300mg reduced LDL-c by -43.11% (95% CI: -52.42, -33.80, p = 0.01). After a median of 8 months (IQR 6-15), Evolocumab reduced the risk of myocardial infarction (MI), OR 0.72 (95% CI: 0.64, 0.81, p<0.01), coronary revascularization, 0.77 (95% CI: 0.70, 0.84, p<0.01), stroke, 0.79 (95% CI: 0.66, 0.94, p = 0.01) and overall MACE 0.85 (95% CI: 0.80, 0.89, p<0.01). Alirocumab reduced MI, 0.57 (0.38, 0.86, p = 0.01), cardiovascular mortality 0.35 (95% CI: 0.16, 0.77, p = 0.01), all-cause mortality 0.60 (95% CI: 0.43, 0.84, p<0.01), and overall MACE 0.35 (0.16, 0.77, p = 0.01).

CONCLUSION

PCSK9 inhibitors (Evolocumab, Alirocumab) and siRNA therapy (Inclisiran) significantly reduced LDL-c by >40% in high-risk individuals. Additionally, both Alirocumab and Evolocumab reduced the risk of MACE, and Alirocumab reduced cardiovascular and all-cause mortality.

Major cardiovascular events increase in long-term proprotein convertase subtilisin/kexin type 9 inhibitors therapy: the Tuscany cost-effective study

BACKGROUND

Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) represent a breakthrough in the treatment of hypercholesterolemia. The aim of this study was to perform a multicentre prospective analysis on the effects of PCSK9i since their distribution in Italy.

METHODS

During the study period (July 2017 to February 2022) 246 patients (mean age 61 ± 11 years, male 73%) who were evolocumab (142/246) or alirocumab (104/246) new users were enrolled in the CERTI (Costo Efficacia Regione Toscana Inibitori PCSK9) study. Lipid value, adverse events (AEs), major cardiovascular events (MACEs) and intima-media thickness were analysed.

RESULTS

PCSK9i therapy allowed a significant improvement in patients' lipid profile [total cholesterol -35%, P < 0.001; triglycerides -9%, P < 0.05; low-density lipoprotein (LDL) cholesterol -51%, P < 0.001; Lp(a) levels -4%, P < 0.05], maintained during the follow-up. No significant variations in intima-media thickness were observed. In the subgroup of patients with more than 1 year of PCSK9i therapy (165/246 patients) we highlighted: a 66% reduction in MACEs compared with the year before recruitment; a progressive increase in MACEs during the follow-up (MACEs event/rate at first year 0.08 vs. MACEs event/rate at year 5: 0.47); a patients cluster with late MACEs older, with higher prevalence of hypertension, smoking habit and peripheral vascular disease. During the follow-up, we recorded AEs in 31% of patients, which mainly resulted in reduction/discontinuation of lipid-lowering therapy for 50 patients or in discontinuation/shift of PCSK9i (respectively 8 and 6 cases).

CONCLUSION

Our data agree with the large evidence on the effectiveness/tolerability of PCSK9i therapy; however, although PCSK9i represents a good cholesterol-lowering therapeutic option, our study shows a progressive increase in MACEs during the late follow-up that deserve further research.