Proprotein Convertase Subtilisin/kexin Type 9 Inhibitors In Patients Research Articles

Use and effectiveness of PCSK-9 inhibitors in heart diseases: A review.

Proprotein Convertase Subtilisin/Kexin type-9 (PCSK-9) inhibitors have recently used in the management of different cardiac complications. Several clinical trials demonstrated their effectiveness in patients with hypercholesterolemia. However, the effectiveness of these medications in patients with heart diseases is still controversial. To review and summarize the clinical trials pertaining to the use and effectiveness of PCSK-9 inhibitors in heart diseases and to discuss the pharmacotherapy of these agents. A review was conducted of all clinical trials with PCSK-9 inhibitors for heart diseases registered at ClinicalTrials.gov since inception up to and including January 19th, 2024. These trials were retrieved. Data from these trials were extracted manually, categorized and analyzed. The number of identified clinical trials was 25,371. After screening and excluding irrelevant studies, 12 studies met the search criteria. The majority of these studies were conducted in the US. The total number of patients in these studies was 27,700. Alirocumab and Evolocumab were the most frequently used PCSK-9 inhibitors. This review identified only a few clinical trials on PCSK-9 inhibitors in heart disease patients. Therefore, it is recommended to conduct more randomized controlled clinical trials on PCSK-9 inhibitors in this patient population.

Early Use of PCSK9 Inhibitors in the Prognosis of Patients with Acute Coronary Syndrome by Protecting Vascular Endothelial Function.

Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) has a protective effect on acute coronary syndrome (ACS). However, most studies have shown that this protective effect is based on a decrease in low-density lipoprotein cholesterol, while other mechanisms remain limited. This study aimed to determine whether PCSK9i can improve the prognosis of ACS patients by protecting endothelial function. A total of 113 ACS patients were enrolled and randomly assigned to PCSK9i group (PCSK9i combined with statins) and control group (statins only). Blood lipids and endothelial function indicators were measured and analyzed 6 weeks before and after treatment. The effect of PCSK9i on the expression and secretion of endothelial function indicators in vascular endothelial cells were studied by cell experiments. After 6 weeks of treatment, endothelial function indicators such as nitric oxide (NO), thrombomodulin, intercellular cell adhesion molecule-1, endothelin-1, and flow-mediated vasodilation were significantly improved in PCSK9i group compared with control group. Only the changes of NO and von Willebrand factor were associated with blood lipid levels, whereas the changes of other endothelial function indicators were not significantly associated with blood lipid levels. PCSK9i reduced the incidence of major adverse cardiovascular events in patients with ACS compared to those in the control group. In cell experiments, PCSK9i treatment significantly ameliorated LPS induced endothelial injury in HUVECs. PCSK9i can protect vascular endothelial function partly independently of its lipid-lowering effect and ameliorate the prognosis of patients with ACS within 6 weeks. This mechanism may involve heat shock transcription factor 1/heat shock proteins -related signaling pathways. Early use of PCSK9i in patients with ACS should be strongly considered in clinical practice.

Safety and efficacy of PCSK9 inhibitor (evolocumab) in patients with non-ST segment elevation acute coronary syndrome and non-culprit artery critical lesions: a randomised controlled trial protocol (SPECIAL study)

IntroductionPatients with non-ST segment elevation acute coronary syndrome (NSTE-ACS) and concomitant multivessel coronary artery disease (CAD) are considered patients with extremely high-risk atherosclerotic cardiovascular disease (ASCVD), and current guidelines specify...

Strike early-strike strong lipid-lowering strategy with PCSK9i in ACS patients. Real-world evidence from AT-TARGET-IT registry.

No data are available on early initiation of proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) in patients with acute coronary syndrome (ACS) in real-world. This study investigates the effects of PCSK9i started at time of ACS hospitalization on lipid control and major CV events in real-world. The lipid control outcome was the percentage of patients reaching the LDL-C target of < 55 mg/dL at first lipid control. The clinical outcome was the incidence of composite major CV events (all cause death, non-fatal MI, non-fatal stroke, and ischemia-driven revascularization) during follow-up in relation to quartiles of LDL-C at first lipid control. We included 771 patients with ACS from AT-TARGET-IT registry, receiving PCSK9i prescription during hospitalization or at discharge. Median LDL-C was 137 mg/dL and decreased to 43 mg/dL at first lipid control. 527 (68.3%) patients achieved LDL-C target at the first lipid control at a median time of 37 days from hospitalization; of them, 404 (76.8%) were discharged on statin plus ezetimibe background therapy. Event curves through a median follow-up of 11 months across quartiles of LDL-C showed a stepwise lower risk of 4P-MACE, 3P-MACE, all-cause mortality, and ischemia-driven revascularization in lower quartile of LDL-C values at first lipid control (<23 mg/dL) and in patients reaching LDL-C <55 mg/dL. Intensive and early lipid-lowering therapy using PCSK9i in patients with ACS (strike early strike strong strategy) is safe and effective in clinical practice and associated with a reduction of residual CV risk.

Safety and Efficacy of PCSK9 Inhibitors in Patients with Acute Coronary Syndrome Who Underwent Coronary Artery Bypass Grafts: A Comparative Retrospective Analysis

Background. The in-hospital reduction in low-density lipoprotein cholesterol (LDL-C) levels following acute coronary syndrome (ACS) is recommended in the current clinical guidelines. However, the efficacy of proprotein convertase subtilisin–kexin type 9 (PCSK9) inhibitors in those patients undergoing coronary artery bypass graft (CABG) has never been demonstrated. Methods. From January 2022 to July 2023, we retrospectively analyzed 74 ACS patients characterized by higher LDL-C levels than guideline targets and who underwent coronary bypass surgery. In the first period (January 2022–January 2023), the patients increased their statin dosage and/or added Ezetimibe (Group STEZE, 43 patients). At a later time (February 2023–July 2023), the patients received not only statins and Ezetimibe but also Evolocumab 140 mg every 2 weeks starting as early as possible (Group STEVO, 31 patients). After one and three months post-discharge, the patients underwent clinical and laboratory controls with an evaluation of the efficacy lipid measurements and every adverse event. Results. The two groups did not differ in terms of preoperative risk factors and Euroscore II (STEVO: 2.14 ± 0.75 vs. STEZE: 2.05 ± 0.6, p = 0.29). Also, there was no difference between the groups in terms of ACS (ST-, Instable angina, or NSTE) and time of symptoms onset regarding total cholesterol, LDL-C, and HDL-C trends from the preprocedural period to 3-month follow-up, but there was a more significant reduction in LDL-C and total cholesterol in the STEVO group (p = 0.01 and p = 0.04, respectively) and no difference in HDL-C rise (p = 0.12). No deaths were reported. In three STEZE group patients, angina recurrence posed the need for percutaneous re-revascularization. No STEVO patients developed significant adverse events. The statistical difference in these serious events, 7% in STEZE vs. 0% in STEVO, was not significant (p = 0.26). Conclusions. Evolocumab initiated “as soon as possible” in ACS patients submitted to CABG with high-intensity statin therapy and Ezetimibe was well tolerated and resulted in a substantial and significant reduction in LDL-C levels at discharge, 1 month, and 3 months. This result is associated with a reduction but without a statistical difference between groups.

The effect of antibody-mediated PCSK9 inhibitor on bare-metal stent implantation outcome

Abstract Introduction Percutaneous coronary intervention (PCI) is the gold standard for the management of acute coronary syndrome, and has been benefited from advances in pharmacotherapy and device innovation. Nevertheless, in-stent restenosis and stent thrombosis remain serious complications following PCI procedure with stent implantation. Proprotein convertase subtilisin kexin type 9 (PCSK9) is an enzyme known for its role in plasma cholesterol homeostasis. Efficiently reducing plasma cholesterol, PCSK9 inhibition recently became a pivotal treatment strategy for hypercholesterolemia. However, the effect of PCSK9 inhibition on stent implantation outcomes remains uninvestigated. Methods Carotid artery bare-metal stent (BMS) implantation was performed on C57Bl/6 mice, which then a parallel assessment of various inflammatory mediators was performed. To inhibit PCSK9, alirocumab was administered weekly to antiplatelet-treated mice started before stent implantation. Six weeks after the stent implantation procedure, animals were harvested and histomorphometric analysis was performed on stented arteries. In vitro cell migration and cellular senescence were also assessed on alirocumab-treated primary human aortic endothelial (EC) and vascular smooth muscle cells (VSMC). Results Compared to sham intervention, stent implantation was associated with increased expression of several inflammatory mediators, including PCSK9. Interestingly, the increase in PCSK9 level was confirmed in the stented vascular tissue, but not in plasma (Fig 1A). Following alirocumab treatment, PCSK9 inhibition results in an increased intimal hyperplasia in the stented vascular segment of alirocumab-treated animals compared to controls (Fig 1B). In vitro, alirocumab promoted migration and inhibited the onset of senescence in primary human VSMC, while blunted the migration and increased the senescence of EC. Conclusion The results of this study demonstrated that antibody-based PCSK9 inhibition worsen bare-metal stent implantation outcome in mice. This observed effect is mediated, in part, by the differential effect on VSMC and EC senescence, thus promoting in-stent intimal hyperplasia while blunting vascular healing. The herein-reported data warrant additional investigations concerning the use of PCSK9 inhibitors in patients undergoing PCI with stent implantation.

PCSK9 Inhibitor Therapy as an Alternative for Statin Intolerance

Scientific relevance. The main cause of cardiovascular pathologies is atherosclerosis, which is secondary to lipid metabolism disorders, in particular, the accumulation of low-density lipoprotein (LDL) cholesterol. Dyslipidaemia treatment with the largest evidence base predominantly includes statins in combination therapy, but their use is limited by into lerance in some patients. Alternatively, the treatment may include proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors.Aim. The study aimed to analyse the applicability of PCSK9 inhibitors in patients with statin intolerance.Discussion. According to the literature analysis, the most common presentation of statin intolerance is statin-associated muscle symptoms. The pathogenesis of statin-associated adverse events is mainly mediated by HMGCoA reductase inhibition, treatment effects on cellular and subcellular processes and skeletal muscles, and patients’ genetic makeup. The mechanism of action of PCSK9 inhibitors is entirely different and involves binding and inactivation of the PCSK9 protein, which lowers blood LDL cholesterol levels. PCSK9 inhibitors have been associated with some adverse drug reactions, most notably immunogenicity; however, PCSK9 inhibitors effectively reduce LDL levels even if patients develop antibodies.Conclusions. Therefore, PCSK9 inhibitors are a safe, well-tolerated, and effec tive therapeutic strategy for hyperlipidaemia in patients with statin intolerance.

Antibody-mediated PCSK9 neutralization worsens outcome after bare-metal stent implantation in mice

AimsDespite advances in pharmacotherapy and device innovation, in-stent restenosis (ISR) and stent thrombosis (ST) remain serious complications following percutaneous coronary intervention (PCI) procedure with stent implantation. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is an enzyme involved in plasma cholesterol homeostasis and recently emerged as a therapeutic target for hypercholesterolemia. Antibody-based PCSK9 inhibition is increasingly used in different subsets of patients, including those undergoing PCI. However, whether PCSK9 inhibition affects outcome after stent implantation remains unknown. Methods and results12 to 14 weeks old C57Bl/6 mice underwent carotid artery bare-metal stent implantation. Compared to sham intervention, stent implantation was associated with increased expression of several inflammatory mediators, including PCSK9. The increase in PCSK9 protein expression was confirmed in the stented vascular tissue, but not in plasma. To inhibit PCSK9, alirocumab was administered weekly to mice before stent implantation. After 6 weeks, histological examination revealed increased intimal hyperplasia in the stented segment of alirocumab-treated animals compared to controls. In vitro, alirocumab promoted migration and inhibited the onset of senescence in primary human vascular smooth muscle cells (VSMC). Conversely, it blunted the migration and increased the senescence of endothelial cells (EC). ConclusionAntibody-based PCSK9 inhibition promotes in-stent intimal hyperplasia and blunts vascular healing by increasing VSMC migration, while reducing that of EC. This effect is likely mediated, at least in part, by a differential effect on VSMC and EC senescence. The herein-reported data warrant additional investigations concerning the use of PCSK9 inhibitors in patients undergoing PCI with stent implantation.

The Association Between PCSK9 Inhibitor Use and Sepsis: A Systematic Review and Meta-Analysis of 20 Double-Blind, Randomized, Placebo-Controlled Trials

ObjectiveThe aim of this study was to determine the impact of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor use on incident sepsis and other severe infections. MethodsWe searched PubMed, EMBASE, CENTRAL, and ClinicalTrial.gov up to September 14, 2021, for double-blind, placebo-controlled randomized trials of alirocumab, evolocumab, or inclisiran with >100 participants in each arm and report of serious adverse events related to infection. Data were synthesized with the fixed-effect Mantel-Haenszel model to generate risk ratios (RRs) with 95% confidence intervals (CIs) of each outcome for PCSK9 inhibitor versus placebo. Main outcome was sepsis. Other outcomes were total severe infections, severe bacterial and viral infections, and severe organ system-specific infections including respiratory tract, gastrointestinal, and genitourinary tract infections. ResultsA total of 20 studies of 64,984 participants were included (alirocumab: n = 7; evolocumab: n = 9; inclisiran: n = 4). Sepsis was reported in 292 (0.51%) participants from 11 trials (PCSK9 inhibitor 0.47%; placebo 0.56%). PCSK9 inhibitor use was not associated with risk of sepsis compared with placebo (Summary RR: 0.85, 95% CI: 0.67-1.07, P = .16); nor was it associated with any severe infection (0.96, 95% CI: 0.89-1.03), severe bacterial (0.96, 95% CI: 0.81-1.14) and viral infections (1.01, 95% CI: 0.77-1.33); nor with any severe organ system-specific infection (all P values >.05). The between-study heterogeneity in all analyses was small. ConclusionThere was neither a beneficial nor a harmful association between PCSK9 inhibitors and risk of sepsis or severe infections. These findings provide reassurance regarding the safety of PCSK9 inhibitors in patients who are concerned about potential drug side effects related to infections.

Treatment with PCSK9 Inhibitors in Patients with Familial Hypercholesterolemia Lowers Plasma Levels of Platelet-Activating Factor and Its Precursors: A Combined Metabolomic and Lipidomic Approach.

Introduction: Familial hypercholesterolemia (FH) is characterized by extremely high levels of circulating low-density lipoprotein cholesterol (LDL-C) and is caused by mutations of genes involved in LDL-C metabolism, including LDL receptor (LDLR), apolipoprotein B (APOB), or proprotein convertase subtilisin/Kexin type 9 (PCSK9). Accordingly, PCSK9 inhibitors (PCSK9i) are effective in LDL-C reduction. However, no data are available on the pleiotropic effect of PCSK9i. To this end, we performed an untargeted metabolomics approach to gather a global view on changes in metabolic pathways in patients receiving treatment with PCSK9i. Methods: Twenty-five FH patients starting treatment with PCSK-9i were evaluated by an untargeted metabolomics approach at baseline (before PCSK9i treatment) and after 12 weeks of treatment. Results: All the 25 FH subjects enrolled were on maximal tolerated lipid-lowering therapy prior to study entry. After a 12 week treatment with PCSK9i, we observed an expected significant reduction in LDL-cholesterol levels (from 201.0 ± 69.5 mg/dL to 103.0 ± 58.0 mg/dL, p < 0.001). The LDL-C target was achieved in 36% of patients. After peak validation and correction, after 12 weeks of PCSK9i treatment as compared to baseline, we observed increments in creatine (p-value = 0.041), indole (p-value = 0.045), and indoleacrylic acid (p-value= 0.045) concentrations. Conversely, significant decreases in choline (p-value = 0.045) and phosphatidylcholine (p-value < 0.01) together with a reduction in platelet activating factor (p-value = 0.041) were observed. Conclusions: Taking advantage of untargeted metabolomics, we first provided evidence of concomitant reductions in inflammation and platelet activation metabolites in FH patients receiving a 12 week treatment with PCSK9i.

Role of PCSK9 Inhibitors in Patients with Familial Hypercholesterolemia.

Patients with familial hypercholesterolemia (FH) are at high or very high risk for cardiovascular disease. Those with heterozygous FH (HeFH) often do not reach low-density lipoprotein cholesterol (LDL-C) targets with statin and ezetimibe therapy, and those with homozygous FH (HoFH) usually require additional lipid-modifying therapies. Drugs that inhibit proprotein convertase subtilisin/kexin type 9 (PCSK9) offer a novel approach to reduce LDL-C. The monoclonal antibodies, alirocumab and evolocumab, given by subcutaneous injection every 2 or 4 weeks produce reductions in LDL-C of 50% to 60% in patients with HeFH, allowing many of them to achieve their LDL-C goals. Patients with HoFH show a reduced and more variable LDL-C response, which appears to depend on residual LDL receptor activity, and those with receptor-negative mutations may show no response. Inclisiran is a long-acting small interfering RNA therapeutic agent that inhibits the synthesis of PCSK9. Subcutaneous doses of 300 mg can reduce LDL-C by more than 50% for at least 6 months and the responses in HeFH and HoFH patients are similar to those achieved with monoclonal antibodies. These PCSK9 inhibitors are generally well tolerated and they provide a new opportunity for effective treatment for the majority of patients with FH.

Lipid-lowering therapies in peripheral artery disease: A review

Peripheral artery disease (PAD) is estimated to affect approximately 8.5 million individuals in the US above the age of 40, and is associated with significant morbidity, mortality, and impairment. Despite the significant adverse limb and cardiovascular (CV) outcomes seen in patients with PAD, there is typically less attention paid to risk factor modification relative to other atherosclerotic diseases such as coronary artery disease (CAD) or stroke. In the current literature, statins have been shown to reduce mortality, major adverse CV events, major adverse limb events, and improve symptomatic outcomes in patients with PAD. In addition, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are emerging as an additional lipid-lowering therapy for patients with PAD. However, despite current guideline recommendations based on growing evidence, patients with PAD are consistently undertreated with lipid-lowering therapies. We provide an extensive literature review and evidence-based recommendations for the use of statins and PCSK9 inhibitors in patients with PAD.

PCSK9 Inhibitors and Ezetimibe Monotherapy in Patients Not Receiving Statins: A Meta-Analysis of Randomized Trials.

Statins are the mainstay of treatment for low-density lipoprotein cholesterol (LDL-C) lowering, however, some patients cannot tolerate statins because of adverse effects. Ezetimibe and proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) are alternative treatment options. The purpose of this meta-analysis was to compare LDL-C reduction with ezetimibe vs PCSK9i in patients not on statins. PubMed and EMBASE were searched until 14th March 2020 for randomized clinical trials (RCTs) assessing the efficacy of ezetimibe vs PCSK9i in patients not on statins. The primary outcome was a reduction in LDL-C levels. A subgroup analysis of statin intolerant patients was also performed. We identified 8 RCTs that enrolled a total of 1602 patients comparing the two pharmacotherapies. PCSK9i lowered LDL-C levels significantly more than ezetimibe (mean difference (MD): -36.5; 95% confidence interval (CI) [-38.3, -34.7, p<0.00001, I2=4%]. In the statin intolerant subgroup, PCSK9i showed significantly greater reduction in LDL-C levels compared with ezetimibe (MD: -36.1; 95% CI [-39.2, -33.1, p<0.00001, I2=21%]. There were no significant differences in LDL-C reduction between different PCSK9i dosages (140 mg once every 2 weeks vs 420 mg once every 4 weeks) (MD: -1.87; 95% CI [-4.45, 0.71, p<0.16, I2=0]. Among patients who are statin intolerant or not receiving statins, PCSK9i use is associated with significantly lower LDL-C levels than after treatment with ezetimibe. PCSK9i might be useful in the prevention and treatment of atherosclerotic cardiovascular disease (ASCVD) in this subset of patients.

Lipoprotein Apheresis and Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitors in Patients With Heterozygous Familial Hypercholesterolemia: A One Center Study.

We evaluated the lipid-lowering (LL) effect of proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) in patients with heterozygous familial hypercholesterolemia (HeFH) treated with LL-drugs and lipoprotein apheresis (LA). The PCSK9i treatment (evolocumab 420 mg/4 weeks, alirocumab 150 mg/2 weeks, or alirocumab 75 mg/2 weeks: 9, 6, and 2 patients, respectively) was initiated in patients with HeFH (n = 17; aged 35-69 years, 10 men, previously treated with statins + ezetimibe ± colesevelam and LA sessions for 2-12 years). A lipid profile was obtained before and immediately after the LA session and before, 1 and 2 months after switching to PCSK9i treatment. The duration of PCSK9i therapy ranged from 3 to 18 months. Median total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG) levels before LA were 268, 198, 46, and 126 mg/dL, respectively, and decreased (at the end of the LA session) to 117, 50, 40, and 51 mg/dL, respectively (P < .001 for TC and P = .001 for all other comparisons). The median time-averaged LDL-C levels following LA were 155 (121, 176; median [25th, 75th percentile]) mg/dL. Median TC, LDL-C, and TG levels before PCSK9i therapy were 269, 190, and 127 mg/dL and decreased to 152, 100, and 95 mg/dL, respectively (P = .002, P < .002, and P < .03, respectively). Steady LDL-C levels with PCSK9i treatment were significantly lower compared with time-averaged LDL-C levels following LA (median value: 100 vs 155 mg/dL; P = .008). With PCSK9i, from 13 patients with CHD, 6 (46.1%) patients achieved LDL-C <70 mg/dL, and 2 patients (15.4%) achieved LDL-C <100 mg/dL. Lipoprotein apheresis was discontinued in all patients except for 2 who continued once monthly. PCSK9i can reduce LDL-C more consistently over time compared with a transient decrease following LA in HeFH patients. PCSK9i therapy may reduce the frequency of LA. Larger trials are required to establish the clinical implications of PCSK9i in patients previously on LA.

2974 PCSK9 Inhibitors Do Not Worsen Liver Function Tests in Patients With Hepatic Steatosis

INTRODUCTION: Hepatic Steatosis is associated with cardiovascular disease independently of classic risk factors. Hepatocytes secrete proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) which in turn inhibits the uptake of low-density lipo-proteins by targeting the receptor for degradation and possibly lipogenesis. Anti-PCSK9 drugs reduce LDL-cholesterol but it is unclear how it affects the liver function in patients with underlying steatosis. AIM: To evaluate the efficacy and safety of PCSK9 inhibitors in patients with Fatty Liver disease. METHODS: A retrospective chart review study was done from September 2015 to January 2018 to include patients currently prescribed PCSK9 inhibitors who had an ICD code of hepatic steatosis or fatty liver disease. Blood AST (aspartate aminotransferase), ALT (alanine aminotransferase), Triglycerides, Cholesterol and HBA1c were charted of patients who were started on this medication and were followed after interval of 12 months while on the medication. This was compared to a control of patients who were not on PCSK9 but did have underlying diagnosis of fatty liver disease. RESULTS: A total of 37 patients on PCSK9 were identified having the ICD 9 and 10 code for fatty liver disease. A random control of 73 patients with the same ICD9/10 code were identified. The mean age of all the patients was 63 (32-90 years), 36% male and 64% female. The mean ALT in the study group after 12 months of PCSK9 therapy was 51 which was not statistically different from the control group (P = 0.05). The average AST value was 43 in the group that was studied and was not statistically significant (P = 0.09). Mean Triglyceride value was 180 (P = 0.87) and mean cholesterol was 143 (P &lt; 0.01). This shows that the drug does significantly reduce the cholesterol values. CONCLUSION: PCSK9 may not have a detrimental effect on the liver profile as observed in our study. There was no significant difference in the liver function test after initiation of the drug. These drugs may serve as alternative agents for those who have experienced or are at risk of hepatic injury.

Recent Updates on the Use of PCSK9 Inhibitors in Patients with Atherosclerotic Cardiovascular Disease

Atherosclerotic cardiovascular disease (ASCVD) is caused by elevated levels of low-density lipoprotein cholesterol (LDL-C). Although statins significantly reduce ASCVD risk, there remains a high degree of residual risk in statin-treated patients. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition has emerged as a significant therapeutic target for further lowering of LDL-C when used in combination with statins. The purpose of this review is to provide an update on recent evidence supporting the use of PCSK9 inhibitors in patients with ASCVD. Alirocumab and evolocumab were approved by the US Food and Drug Administration in 2015. Multiple phase II and III studies have demonstrated that these agents reduce LDL-C levels by up to 60% and are relatively safe, with the exception of injection site reactions. Additionally, two randomized controlled clinical trials have demonstrated that both alirocumab and evolocumab reduce ASCVD events when used in combination with statin therapy compared to statin alone. In light of this evidence, the 2018 Cholesterol Guideline incorporated PCSK9 inhibitors into the treatment algorithm for select secondary prevention patients unable to achieve an LDL-C below 70mg/dL despite maximally tolerated statin plus ezetimibe. Although PCSK9 inhibitors provide substantial reductions in LDL-C levels and reduce ASCVD events in secondary prevention populations, the cost-effectiveness of alirocumab and evolocumab limit widespread use. Additional research is needed to explore the role of PCSK9 inhibitors in other populations, including primary prevention, patients unable to tolerate statins, and acute myocardial infarction.

Lipoprotein(a) and proprotein convertase subtilisin/kexin type\xa09 inhibitors

Lipoprotein(a) (Lp(a)) is an internationally accepted independent atherogenic risk factor. Details about its synthesis, many aspects of composition and clearance from the bloodstream are still unknown. LDL receptor (LDLR) (and probably other receptors) play a role in the elimination of Lp(a) particles. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors increase the number of available LDLRs and in this way very effectively reduce the LDL cholesterol (LDL-C) concentrations. As shown in controlled studies using PCSK9 inhibitors, Lp(a) levels are decreased by 20 to 30%, though in some patients no effect was observed. So far, it has not been clarified whether this decrease is associated with an effect on the incidence of cardiovascular events (CVEs). In two recently published well-performed secondary prevention studies (FOURIER with evolocumab, ODYSSEY OUTCOMES with alirocumab) baseline Lp(a) levels were shown to have an impact on CVEs independently of baseline LDL-C concentrations. The rather modest PCSK9 inhibitor-induced decrease of Lp(a) was associated with a reduction of CVEs in both studies, even after adjusting (ODYSSEY OUTCOMES) for demographic variables (age, sex, race, region), baseline Lp(a), baseline LDL-C, change in LDL-C, and clinical variables (time from acute coronary syndrome, body mass index, diabetes, smoking history). The largest decrease of CVEs was seen in patients with relatively low concentrations of both LDL-C and Lp(a) (FOURIER). These findings will probably have an influence on the use of PCSK9 inhibitors in patients with high Lp(a) concentrations.

Treatment of hypercholesterolaemia with PCSK9 inhibitors in patients after cardiac transplantation.

BackgroundHypercholesterolaemia is common in patients after cardiac transplantation. Monoclonal antibodies that inhibit proprotein convertase subtilisin-kexin type 9 (PCSK9) reduce low-density lipoprotein (LDL) cholesterol levels and subsequently the risk of cardiovascular events in patients with dyslipidaemia. There are no published data on the effect of this medication class on cholesterol levels in patients after cardiac transplantation.MethodsIn this retrospective study we investigated patients who were treated with PCSK9 inhibitors either because of intolerance of statins or residual hypercholesterolaemia with evidence of cardiac allograft vasculopathy. We compared the data of patients prior to the start with these medications with their most recent dataset.ResultsTen patients (nine men; mean age 58±6 years) underwent cardiac transplantation 8.3±4.5 (range 3–15) years ago. The treatment duration of Evolocumab or Alirocumab was on average 296±125 days and lead to a reduction of total Cholesterol (281±52 mg/dl to 197±36 mg/dl; p = 0.002) and LDL Cholesterol (170±22 mg/dl to 101±39 mg/dl; p = 0.001). No significant effects on HDL Cholesterol, BNP, Creatin Kinase or hepatic enzymes were noticed. There were no unplanned hospitalisations, episodes of rejections, change of ejection fraction or opportunistic infections. Both patients on Alirocumab developed liver pathologies: One patient died of hepatocellular carcinoma and the other developed hepatitis E.ConclusionsOur study demonstrates that the PCSK9 inhibitors Evolocumab and Alirocumab lead to a significant reduction of LDL Cholesterol in heart transplantation recipients. No effect on cardiac function or episodes of rejections were noticed. Larger and long-term studies are needed to establish safety and efficacy of PCSK9 inhibitors after cardiac transplantation.

Role of PCSK9 Inhibitors in High Risk Patients with Dyslipidemia: Focus on Familial Hypercholesterolemia.

Familial hypercholesterolemia (FH) is an inherited autosomal dominant disorder that is characterized by substantially increased Low-Density Lipoprotein Cholesterol (LDL-C) levels. Patients with FH have a significantly higher risk for Cardiovascular (CV) events, and the timely reduction of LDL-C is of paramount importance to ameliorate the risk for CV disease. Among the available lipid-lowering therapies, the novel Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) inhibitors have emerged as a very promising class of drugs for the management of such patients. The purpose of this review is to present available data on the efficacy and safety of the two available PCSK9 inhibitors in patients with FH, and importantly to discuss potential differences between the two drugs. A comprehensive literature search was performed to identify available data from clinical studies evaluating the impact of evolocumab or alirocumab on lipid and CV parameters in patients with FH. Several studies have assessed the lipid-lowering profile of PCSK9 inhibitors in patients with FH. Both evolocumab and alirocumab were found to significantly reduce LDL-C by more than 50-60% in FH patients. Furthermore, data also support a lower rate of lipid apheresis in FH patients receiving a PCSK9 inhibitor. In terms of CV outcomes, both drugs were found to possess CV-ameliorating effects of the same extent in patients with CV disease. However, alirocumab reduced all-cause mortality, as well, a finding not observed with evolocumab. Several differences in the study population characteristics might explain this and other mild differences observed in the CV trials of these drugs. Available evidence suggests similar potency of alirocumab and evolocumab in reducing lipids and CV events.

Update on the use of PCSK9 inhibitors in adults: Recommendations from an Expert Panel of the National Lipid Association

An Expert Panel convened by the National Lipid Association was charged with updating the recommendations on the use of proprotein convertase subtilisin/kexin type 9 (PCSK9) antibody therapy that were provided by the 2015 National Lipid Association Recommendations for the Patient-Centered Management of Dyslipidemia: Part 2. Recent studies have demonstrated the efficacy of these agents in reducing low-density lipoprotein cholesterol and non–high-density lipoprotein cholesterol and have confirmed their excellent safety profile. A cardiovascular outcomes study has shown that these agents reduce incident atherosclerotic cardiovascular disease (ASCVD) events in patents with stable ASCVD and concomitant risk factors. The current update provides the Expert Panel's evidence-based recommendations on the clinical utility of PCSK9 inhibitors in patients with stable ASCVD, progressive ASCVD, LDL-C ≥ 190 mg/dL (including polygenic hypercholesterolemia, heterozygous familial hypercholesterolemia and the homozygous familial hypercholesterolemia phenotype) and very-high-risk patients with statin intolerance.