PCSK9 Research Articles

Effect of alirocumab on coronary plaque stratified by atherothrombotic risks

Abstract Background Previous clinical studies have shown that high-risk subgroups including patients with major atherosclerotic cardiovascular disease (ASCVD) events and multiple atherothrombotic risk factors derive enhanced cardiovascular benefit from proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition. To date, the effect of alirocumab on coronary plaque regression stratified by the number of atherothrombotic risk factors remains unknown. Purpose To investigate the utility of atherothrombotic risk stratification to identify patients with acute myocardial infarction (AMI) who have the greatest potential for benefit on plaque regression as assessed by intracoronary imaging from the addition of alirocumab to high-intensity statin therapy. Methods This was a substudy of the PACMAN trial, a randomized, double-blind trial comparing biweekly alirocumab (150 mg) versus placebo in AMI patients undergoing percutaneous coronary intervention. Intravascular ultrasound (IVUS) was serially performed in non-infarct-related coronary arteries at baseline and after 52 weeks. Atherothrombotic risk factors defined in the 2018 ACC/AHA cholesterol guidelines include myocardial infarction, ischemic stroke, peripheral artery disease, age ≥65 years, familial hypercholesterolemia, coronary revascularization, diabetes, hypertension, chronic kidney disease, current smoking, LDL-C ≥100 mg/dL despite maximum tolerated statin therapy, and history of heart failure. The key endpoint was the change in IVUS-derived percent atheroma volume (PAV) from baseline to 52 weeks. Results A total of 263 patients available for serial IVUS data were analyzed for the current study. The most prevalent atherothrombotic risk factors were current smoking (49%), hypertension (43%), and age ≥65 years (24%). Patients were divided into 3 groups according to the number of risk factors (0 risk factor: n=52, 1 risk factor: n=101, ≥2 risk factors: n=100). Patients with risk factors had greater PAV at baseline compared with those with 0 risk factor (39.0% vs. 42.6% vs. 42.8%, P=0.008). The addition of Alirocumab to high-intensity statin therapy demonstrated a significant reduction in PAV among patients with 0 risk factor (-2.66% vs. -1.02%, P=0.009) and those with 1 risk factor (-2.36% vs. -0.76%, P<0.001) (Figure 1). In contrast, patients with ≥2 risk factors had no significant PAV reduction by alirocumab (-1.72% vs. -1.12%, P=0.076, P for interaction=0.009). Conclusions Among AMI patients with no or 1 atherothrombotic risk factor, the addition of alirocumab to high-intensity statin therapy demonstrated greater coronary plaque regression. Patients with fewer risk factors thus appear to be more susceptible for atheroma regression.Change in PAV stratified by risk factors

Efficacy of lipid lowering therapy beyond statins to prevent cardiovascular events

Abstract Background Lipid lowering therapy is a key cornerstone in secondary prevention of patients with coronary artery disease. However, only a minority of patients with statin therapy reach LDL thresholds as suggested by the ESC. Ezetimibe, bempedoic acic, and proprotein convertase subtilisin/kexin type 9 (PCSK-9) (synthase-) inhibitors allow for the reduction in LDL-cholesterol in addition to statin therapy. Purpose We aimed to perform a meta-analysis of existing trials, evaluating how lipid lowering therapy beyond statins impacts cardiovascular outcome. In specific, we evaluated the potential influence of duration of follow-up on the association with mortality endpoints. Methods We performed a systematic search using the Pubmed, Cochrane, SCOPUS, and Web of Science databases for studies, evaluating the impact of an intensified lipid lowering therapy via ezetimibe, bempedoic acid, Bococizumab, Alirocumab, Evolocumab, Inclisiran in addition to statin therapy compared to statin therapy alone. Manuscript and congress presentations, published until 1st of August 2023, were included. We made our search specific and sensitive using Medical Subject Headings terms and free text and considered studies published in English language. Search terms used were : "Bempedoic Acid" or "Bococizumab" or "Alirocumab" or "Evolocumab" or "Ezetimibe" or "Inclisiran" and "statin" and "cardiovascular events". Results A total of 123,785 patients from 15 randomized controlled trials (IMPROVE-IT, FOURIER, ODYSSEY Outcomes, ODYSSEY LONG TERM, EWTOPIA 75, PACMAN-AMI, RACING, SIPRE I, SPIRE II, OSLER-1 and OSLER-2, CLEAR HARMONY, CLEAR OUTCOMES, CLEAR SERENITY, CLEAR WISDOM) were included. Treatment with ezetimibe or a PCSK-9 inhibitor was associated with a 19% risk reduction in cardiovascular events (OR [95%CI]: 0.81 [0.75; 0.86]). Effect sizes were similar for myocardial infarction (0.81 [0.74; 0.89]) and even more pronounced for ischemic stroke (0.77 [0.70; 0.84]). In contrast, all-cause mortality was not improved by the intensified lipid lowering therapy (0.99 [0.93; 1.04]). Stratifying by follow-up duration of < vs. ≥ 3 years, no improvement in all-cause mortality was observed in both groups (<3 years: 1.04 [0.93; 1.17]; ≥3 years: 0.97 (0.88; 1.06). No relevant heterogeneity and inconsistency between groups was present in all analyses (detailed data not shown). Conclusion Intensified LDL-lowering therapy with ezetimibe, bempedoic acic or PCSK-9 inhibitors, in addition to statins, reduces the risk of myocardial infarction and stroke, however, does not impact overall mortality. A potential survival benefit was also not observed in studies with follow-up duration of ≥ 3 years.

PCSK9 inhibitors in HIV patients with dyslipidemia

Abstract Introduction Cardiovascular disease has become increasingly prevalent in the HIV (human immunodeficiency virus) population. Antiretroviral therapy and HIV itself independently increase the risk of dyslipidemia. While statins are currently the predominant therapy to treat dyslipidemia in HIV patients, drug-drug interactions and adverse drug events can limit their use. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a naturally occurring inhibitor of the LDL-receptor pathway. PCSK9 inhibitors offer an alternative in patients who cannot tolerate or need additional therapy in addition to statin for optimal dyslipidemia management. Purpose The purpose of this study is to compare major adverse cardiovascular events in HIV patients on a PCSK9 inhibitor (evolucumab, alirocumab, inclisiran) vs patients not on a PCSK9 inhibitor. Methods A retrospective cohort study was conducted using electronic medical records from a global federated health research network. The TriNetX network was searched on February 10, 2024, including records from 2020 to 2024. Patients were included based on a diagnosis of HIV status and concomitant dyslipidemia. Patients with HIV and dyslipidemia on a PCSK9 inhibitor were propensity-score matched for age, sex, race, and comorbidities with patients who were not on a PCSK9 inhibitor. The outcomes were mortality, myocardial infarction, heart failure and stroke. Results A total of 485 patients were included in the study. PCSK9 inhibitor use associated with 9% lower odds of all-cause mortality (odds radio, .29; 95% CI, 0.18-0.48; p<.0001). PCSK9 inhibitor use was also associated with 8% lower odds of heart failure (odds radio, .63; 95% CI, 0.47-0.85; p<.0023). No significant associations were noted for myocardial infarction (odds radio, .87; 95% CI, 0.63-1.21; p=0.406) or stroke (odds radio, .67; 95% CI, 0.45-1.01; p=0.052). Conclusion The role of dyslipidemia in HIV is challenging due the complex pathophysiology of HIV. There is an apparent increased risk of cardiovascular disease from the infection itself as well current antiretroviral therapies. While current guidelines recommend the use of statins as first line therapy for dyslipidemia in this population, the drug-drug interaction of statins with ARTs, as well as their side effects, limit their use at times. PCSK9 inhibitors are associated with lower odds of all-cause mortality and heart failure. No significant association was seen for myocardial infarction or stroke. They should be considered as an early intervention alongside statins in HIV patients with dyslipidemia. Further research should be done for the long term safety and tolerance of this therapy as well as cost-effectiveness and access to PCSK9 inhibitors in this population.

Multi-biomarker approach for predicting cardiac magnetic resonance parameters at 30 days after ST-segment elevation myocardial infarction

Abstract Background Prior data showed associations of circulating Proprotein Convertase Subtilisin / Kexin type 9 (PCSK9) and inflammatory/anti-fibrotic Cellular Communication Network factor 1 (CCN1) at index ST-segment elevation acute myocardial infarction (STEMI) with left ventricular ejection fraction at 6 and 12 months, respectively and for CCN1 also with infarct size. Purpose PCSK-9, CCN1 and reference biomarkers high-sensitivity Troponin T (hsTNT) and N-terminal pro-brain natriuretic peptide (NTproBNP) were measured in patients from the CLEVER-ACS trial (clinicaltrials.gov NCT01529554) at presentation with STEMI and correlated with clinically relevant cardiac magnetic resonance (CMR) parameters at 30 days. Methods Associations between baseline biomarkers (PCSK-9, CCN1, hsTNT, NTproBNP) and CMR parameters at 30 days were evaluated using Spearman correlation and linear regression analysis (dichotomised at their median). Receiver operating characteristic (ROC) and area under the curve (AUC) were determined for significant values based on correlation analysis; AUC > 0,7 considered relevant. CMR parameters comprised left ventricular structural and functional parameters including scar mass and microvascular obstruction. Results We identified 56 STEMI patients (mean age 61.7 ± 11.2 (SD) years) who completed 30 days follow-up with biomarker data. Among biomarkers, significant associations with CMR parameters were only found for hsTNT, and NTproBNP. The strongest associations were found for left ventricular ejection fraction (LVEF; hsTNT RSp =-0.66; NTproBNP RSp =-0.57), left ventricular scar (LVSCAR; hsTNT RSp =0.58; NTproBNP RSp =0.56) and scar mass (SM; hsTNT RSp =0.65; NTproBNP RSp =0.55). Conversely, left ventricular end-diastolic volume index (LVEDVI; hsTNT RSp =0.47; NTproBNP RSp =0.32), left ventricular end-systolic volume index (LVESVI; hsTNT RSp =0.51; NTproBNP RSp =0.39) and microvascular obstruction (MVO; hsTNT RSp =0.34; NTproBNP RSp =0.34) were significantly, albeit only modestly associated. ROC and AUC analysis yielded relevant associations of biomarkers with CMR parameters LVEF (hsTNT=0.79; NTproBNP=0.81), LVSCAR (hsTNT=0.84; NTproBNP=0.76) and scar mass (hsTNT=0.83; NTproBNP=0.78). Furthermore, relevant associations of biomarkers with CMR were found for LVEDVI (hsTNT=0.79; NTproBNP=0.72), LVESVI (hsTNT=0.84; NTproBNP=0.72) and MVO (hsTNT=0.72; NTproBNP=0.71). Conclusion Baseline levels of hsTNT and NT-proBNP are strong predictors for functional and dimensional CMR parameters of the left ventricle including clinically relevant imaging surrogates of myocardial injury shortly after STEMI.ROC LVEF

Discovery of Truncated Cyclic Peptides Targeting an Induced-Fit Pocket on PCSK9.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) regulates plasma low-density lipoprotein cholesterol (LDL-C) levels by promoting hepatic LDL receptor (LDL-R) degradation. We previously identified and optimized 13-mer cyclic peptides that bind to a novel, induced-fit pocket adjacent to the binding interface of PCSK9 and LDL-R and effectively disrupted the PCSK9/LDL-R protein-protein interaction (PPI) both in vitro and in vivo. However this series of large cyclic peptides required charged groups for function and lacked oral bioavailability in rodents. We describe herein multiple structure-based modifications to these original peptides to yield truncated, neutral molecules with full PPI function in both biochemical and cellular assays. In parallel, new mRNA-peptide display screens identified non-functional 8- and 9-mer compounds which ligand the induced-fit pocket in a distinct manner. Taken together, these studies indicate multiple directions to reduce the size and complexity of this peptide class toward a true small molecule oral agent.

Rationale for Early Administration of PCSK9 Inhibitors in Acute Coronary Syndrome.

Acute coronary syndromes (ACSs) represent a significant global health challenge arising from atherosclerotic cardiovascular disease (ASCVD), with elevated low-density lipoprotein cholesterol (LDL-C) levels being a primary contributor. Despite standard statin therapy, individuals with ACS remain at high risk for recurrent cardiovascular events, particularly in the initial post-ACS period. Monoclonal antibodies targeting proprotein convertase subtilisin/kexin type 9 (PCSK9), such as evolocumab and alirocumab, offer a potential strategy to reduce LDL-C levels further and mitigate this residual risk. This review delves into the molecular mechanisms, effects on cholesterol metabolism, inflammatory modulation, and clinical outcomes associated with early administration of PCSK9 inhibitors following ACS.

Clinical reality and challenges with familial hypercholesterolemia patients' management. 2024 results from the Regional Center for Rare Diseases (RCRD) Registry in Poland

BackgroundDespite advancements in early diagnosis and effective medications in last decade, most heterozygous familial hypercholesterolemia (heFH) patients still fail to achieve their low-density lipoprotein cholesterol (LDL-C) goals and remain at residual cardiovascular disease risk. We present recent data from the regional FH registry in Poland, highlighting the challenges and real-life clinical management of FH patients. MethodsThe registry is held at the Regional Centre for Rare Diseases, founded in 2016, at the 2nd largest, supraregional hospital in Poland, where >80 different rare diseases in patients from all over Poland are diagnosed and treated, including phenotypically or genetically diagnosed FH patients. Our analysis focused on both children and adult FH patients, excluding those treated with inclisiran due to a small sample size (n = 5). ResultsWe studied 173 consecutive heFH patients, median age for adult population was 40 years (range: 27–57), of whom 56.14 % were women. Among the population, 82.1 % were adults (n = 142), and 31 were children (17.92 %; median age 9 (8–13), females 58.16 %). Children exhibited lower total cholesterol and triglyceride levels compared to adults, with no significant differences in LDL-C and high-density lipoprotein cholesterol (HDL-C) levels. Molecular diagnosis in the whole population revealed that 76.6 % had an LDL receptor (LDLR) mutation, while 23.4 % had an apolipoprotein B (APOB) mutation. Risk assessment categorized patients into high (70.7 %), very high (22.1 %), and extremely high (7.1 %) risk groups. Triple therapy achieved treatment goals in 61.76 % of adults and 70.97 % of children. At baseline, 36.62 % of adult patients were not using statins. High-intensity statin therapy combined with ezetimibe was initiated for the remaining patients. Only 3.33 % of patients avoided statins due to complete intolerance. Ezetimibe was used in 57.27 % of patients (mostly in combination therapy), and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors were prescribed for 28.17 % FH patients. In adults receiving statin and ezetimibe therapy, median achieved LDL-C was 141 mg/dl (107–184). For triple therapy, median achieved LDL-C was 52.5 mg/dL (32–86.5). Overall median achieved LDL-C in the study population was 99.5 mg/dl (57.5–145.4). PCSK9 inhibitors reduced LDL-C by 165.6 mg/dl. Combination therapy did not significantly alter baseline lipoprotein(a) (Lp(a)) levels (p = 0.134), and PCSK9 inhibitors led to a mean Lp(a) reduction of 18.66 mg/dl (45 % reduction; p = 0.013). Multivariable regression analysis identified key factors for achieving LDL-C targets in FH patients: DLCN total score, DLCN category, ezetimibe use, and PCSK9 inhibitors. ConclusionsIn Poland, FH patients are often diagnosed too late (usually over 40 years of age), and many still do not reach their LDL-C goals. Combination LLT double or triple therapy significantly increases the likelihood of achieving LDL-C targets – even up to fivefold. Therefore, unrestricted access to PCSK9 inhibitors for all FH patients is crucial, without the current limitations imposed by drug reimbursement programs like B101.

HMGCR as a promising molecular target for therapeutic intervention in aortic aneurisms: a mendelian randomization study

BackgroundDespite the exploration of the connections between serum low-density lipoprotein cholesterol (LDL-C) levels and aneurisms in epidemiological studies, causality remains unclear. Therefore, this study aimed to assess the causal impact of LDL-C-lowering targets (HMGCR, PCSK9, NPC1L1, CETP, APOB, and LDLR) on various forms of aneurisms using Mendelian Randomization (MR) analysis.MethodsTwo genetic instruments acted as proxies for exposure to LDL-C-lowering drugs: expression quantitative trait loci of drug target genes and genetic variants linked to LDL-C near drug target genes. Summary-data-based MR (SMR), inverse-variance-weighted MR (IVW-MR), and multivariable MR (MVMR) methods were employed to compute the effect estimates.ResultsThe SMR analysis revealed substantial associations between increased HMGCR expression and a heightened risk of aortic aneurism (odds ratio [OR] = 1.603, 95% confidence interval [CI] = 1.209–2.124), thoracic aortic aneurism (OR = 1.666, 95% CI = 1.122–2.475), and abdominal aortic aneurism (OR = 1.910, 95% CI = 1.278–2.856). Likewise, IVW-MR analysis demonstrated positive correlations between HMGCR-mediated LDL-C and aortic aneurism (OR = 2.228, 95% CI = 1.702–2.918), thoracic aortic aneurism (OR = 1.751, 95% CI = 1.191–2.575), abdominal aortic aneurism (OR = 4.784, 95% CI = 3.257–7.028), and cerebral aneurism (OR = 1.993, 95% CI = 1.277–3.110). Furthermore, in the MVMR analysis, accounting for body mass index, smoking, and hypertension, a significant positive relationship was established between HMGCR-mediated LDL-C levels and the development of aortic aneurisms, encompassing both thoracic and abdominal subtypes. Similarly, consistent positive associations were observed for PCSK9 and CETP genes, as well as PCSK9-mediated and CETP-mediated LDL-C levels, with the occurrence of aortic aneurism and abdominal aortic aneurism. Nonetheless, the evidence for potential associations between APOB, NPC1L1 and LDLR with specific subtypes of aortic aneurisms lacked consistent support from both SMR and IVW-MR analyses.ConclusionsOur MR analysis offered compelling evidence of a plausible causal link between HMGCR and an increased risk of aortic aneurism, encompassing both thoracic and abdominal types. These groundbreaking findings further bolster the case for the deployment of HMGCR inhibitors in the treatment of aortic aneurisms, including both thoracic and abdominal variants.

Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) Inhibitors as Adjunct Therapy to Statins: A New Frontier in Cardiovascular Risk Reduction.

Lowering low-density lipoprotein cholesterol (LDL-C) plasma levels is crucial for the prevention of primary and secondary cardiovascular diseases (CVDs). Many patients struggle to obtain goal LDL-C levels, despite the availability of several lipid-lowering medications, because of limited efficaciousness and unfavorable side effects. Proprotein convertase subtilisin/kexin type 9 (PCSK9) targeting has drawn interest recently as a novel approach to further lower cardiovascular (CV) risk. The number of receptors accessible to remove LDL-C from the bloodstream is reduced when PCSK9 attaches to LDL-C receptors and directs them toward lysosomal destruction. LDL receptor activity is increased by PCSK9 inhibition, which attracts therapeutic intervention. Despite concurrent statin therapy, phase 3 clinical trials have demonstrated encouraging outcomes with monoclonal antibodies against PCSK9, such as evolocumab and alirocumab, resulting in significant reductions in LDL-C levels. This study intends to investigate recent advancements in the field to evaluate PCSK9 inhibitors' safety, effectiveness, and potential for preventing CVD. The investigation will also review potential future paths and wider effects of using PCSK9 inhibitors in therapeutic settings.

Safety of Inclisiran: A Disproportionality Analysis from the EudraVigilance Database.

Introduction: The discovery of serine protease proprotein convertase subtilisin-kexin type 9 (PCSK9) has revolutionized pharmacological lipid-lowering treatments. The first PCSK9 antagonists (PCSK9-A), evolocumab and alirocumab, were approved in 2015. Targeting PCSK9 synthesis marked a major advancement in this field, leading to the development of inclisiran, a long-acting siRNA targeting PCSK9 mRNA. However, real-world safety data on this drug are still limited. Therefore, this study aims to provide a real-world safety evaluation of inclisiran, comparing its characteristics to those of PCSK9-As. Methods: A retrospective pharmacovigilance study was conducted using EudraVigilance (EV). Inclisiran-related individual case safety reports (I-ICSRs) from 01/01/2021 to 06/30/2023 were retrieved. ICSRs for evolocumab or alirocumab from 01/01/2015 to 06/30/2023 were collected as a reference group (RG). ADRs were classified using the MedDRA dictionary. Data were evaluated using descriptive and disproportionality analyses. Crude reporting odds ratio (ROR) with 95% confidence intervals (CI) were used as disproportionality measures. Results: Of the 15,236 ICSRs, 3.7% (n = 563) involved inclisiran, with the rest in the RG. Most I-ICSRs involved female patients (51.7%) aged 18 to 64 (52.8%). The most-reported ADRs for inclisiran were "general disorders and administration site conditions" (n = 347) and "investigations" (n = 277). Significant disproportionality was found in I-ICSRs compared to the RG for "Myalgia" (ROR: 2.43; 95% CI: 1.94-3.04), "Low-density lipoprotein increased" (ROR: 11.95; 95% CI: 9.10-15.52), and "Drug ineffective" (ROR: 6.37; 95% CI: 4.64-8.74). Conclusions: The inclisiran safety profile aligns with the existing literature and pre-commercial data. However, further studies are needed to fully understand the observed differences with PCSK9-As.

Recaticimab Monotherapy for Nonfamilial Hypercholesterolemia and Mixed Hyperlipemia: The Phase 3 REMAIN-1 Randomized Trial

BackgroundMonoclonal antibodies against proprotein convertase subtilisin/kexin type 9 (PCSK9) have been used to reduce the level of low-density lipoprotein cholesterol (LDL-C), but require either biweekly or monthly dosing frequency. Recaticimab is a new humanized monoclonal antibody selectively targeting PCSK9, with long-acting characteristic. ObjectivesThe purpose of this study was to assess the efficacy and safety of recaticimab monotherapy in patients with nonfamilial hypercholesterolemia and mixed hyperlipemia at low-to-moderate atherosclerotic cardiovascular disease (ASCVD) risk, and to explore different dosing strategies to provide patients with flexible administration options. MethodsThis was a randomized, double-blind, placebo-controlled, phase 3 study conducted at 59 sites in China. Patients with fasting LDL-C ≥2.6 to <4.9 mmol/L, fasting triglyceride ≤5.6 mmol/L, and 10-year ASCVD risk score <10% were randomly assigned (2:2:2:1:1:1) to receive subcutaneous injections of recaticimab at 150 mg every 4 weeks (Q4W), 300 mg every 8 weeks (Q8W), or 450 mg every 12 weeks (Q12W), or matching placebo, on background lipid-lowering diet. Primary endpoint was percentage change in LDL-C from baseline to week 12 for 150 mg Q4W and 450 mg Q12W and to week 16 for 300 mg Q8W. ResultsA total of 703 patients underwent randomization and received recaticimab (n = 157, 156, and 155 for 150 mg Q4W, 300 mg Q8W, and 450 mg Q12W, respectively) or placebo (n = 78, 79, and 78, respectively). Compared with placebo, recaticimab further reduced LDL-C by 49.6% (95% CI: 44.2%-54.9%) at 150 mg Q4W, 52.8% (95% CI: 48.3%-57.2%) at 300 mg Q8W, and 45.0% (95% CI: 41.0%-49.0%) at 450 mg Q12W (P < 0.0001 for all comparisons). Safety with recaticimab was comparable to placebo. After 12 or 16 weeks of treatment, patients who received recaticimab continued treatment until week 24, whereas those allocated to placebo were switched to recaticimab treatment with the same dosing strategy. Both 24-week recaticimab and 12- or 8-week recaticimab switched from placebo were effective. With 24 weeks of recaticimab treatment, the most common treatment-related adverse event was injection site reaction (n = 23 [4.9%]). ConclusionsRecaticimab monotherapy yielded significant LDL-C reductions and showed comparable safety vs placebo in patients with nonfamilial hypercholesterolemia and mixed hyperlipemia at low-to-moderate ASCVD risk, even with an infrequent dosing interval up to Q12W.

Dihydrotanshinone I promotes LDL uptake by HepG2 cells through increasing LDLR level

ABSTRACT Dihydrotanshinone I (DHT), a lipophilic compound extracted from Salvia miltiorrhiza, has cardiovascular protective effects, but the underlying molecular mechanisms of action have rarely been reported. Based on this, whether DHT affects cholesterol metabolism by regulating LDLR is investigated in this work. The results revealed that DHT can increase LDLR expression and promote LDL uptake by HepG2 cells. Meanwhile, DHT stabilizes LDLR mRNA expression by activating the epidermal growth factor receptor/extracellular signal-regulated kinase 1/2 (EGFR/erk1/2) signaling pathway. In addition, DHT inhibits the expression of the proprotein convertase subtilisin/kexin type 9 (PCSK9) by down-regulating the liver nuclear transcription factor 1 A (HNF1A) and up-regulating the forkhead box O3 (FOXO3). All of these indicate that DHT increases LDLR expression at the post-transcriptional and post-translational levels thereby promoting LDL-C metabolism. The potential mechanism of DHT to improve lipid metabolism has been revealed as a promising drug against AS.

A register-based cohort study on the effectiveness and Safety of anti-PCSK9 treatment in persons with hyperlipidemia.

Dyslipidemia is a known risk factor for cardiovascular disease. While statins are the primary treatment, some individuals require additional lipid-lowering therapies, such as proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors. Alirocumab and evolocumab have shown efficacy in reducing low-density lipoprotein cholesterol (LDL-C) levels and reduce the risk of major cardiovascular events (MACE) but have not been directly compared in clinical trials. This study aims to assess the effects of PCSK9 inhibitors on LDL-C levels and evaluate the impact of a mandated switch from alirocumab to evolocumab. Taking advantage of the mandated switch in PCSK9 treatment in Denmark, we conducted a register-based cohort study of 907 individuals with dyslipidemia treated with PCSK9 inhibitors in the Capital Region of Denmark from 2016 to 2022. We analyzed LDL-C levels, treatment retention, and MACE, adjusting for variables such as age, sex, dose, and concurrent lipid-lowering medications. We show that PCSK9 inhibitors treatment resulted in a 49% reduction in LDL-C levels. Following a mandated switch from alirocumab to evolocumab, no significant difference was observed in LDL-C levels or adverse clinical outcomes, including MACE. Treatment discontinuation was most likely within the first 100 days, and no significant difference in discontinuation rates was found between the two drugs. Our study demonstrates that both alirocumab and evolocumab are effective in significantly reducing LDL-C levels in individuals with dyslipidemia. The mandated switch from alirocumab to evolocumab did not result in significant changes in LDL-C or clinical outcomes, suggesting that these treatments can be used interchangeably. These findings support the clinical equivalence of the two PCSK9 inhibitors and may guide therapeutic decisions in lipid management.

12369 Clinical Experience With Inclisiran At An Academic Center

Abstract Disclosure: L. Chavez Marin: None. M. Gonzalez: None. M.F. Linton: None. B.G. Carranza Leon: None. Background: Inclisiran, a small interfering RNA (siRNA) molecule designed to inhibit proprotein convertase subtilisin/kexin type 9 (PCSK9), is the only siRNA approved for management of elevated low-density lipoprotein cholesterol (LDL-C) in both primary (for patients with familial hypercholesterolemia) and secondary prevention of cardiovascular disease. In clinical trials, Inclisiran has been shown to reduce LDL-C by more than 50% in populations at high cardiovascular risk. However, real world data about its tolerability and efficacy is still limited. Methods: We conducted an electronic medical record search to identify subjects who were prescribed Inclisiran at a lipid clinic within Vanderbilt University Medical Center (Nashville, USA). Subjects were included if they received at least one dose of Inclisiran and had pre- and post- LDL-C levels. Subjects taking other LDL-C lowering medications like statins, ezetimibe, bempedoic acid, and PCSK-9 inhibitors were included. Pre- and post- LDL-C averages were calculated and analyzed with 95% confidence intervals. The reasons for medication discontinuation were also examined. Results: Out of 69 subjects identified, only 19 met criteria for inclusion, while 32 never received a dose due to cost burden and insurance denial. The other 18 subjects were not included due to inadequate lab results at the time of data collection. In subjects who received at least one dose of Inclisiran, average pre-LDL-C was 142 mg/dL [CI: 34.7] while post-LDL-C was 77 mg/dL [CI: 24.0], notable for a 46% decrease in LDL-C levels. These subjects were also receiving another lipid lowering agent, like a statin, or had previously used a monoclonal antibody-PCSK-9 inhibitor. Those without prior use of PCSK-9 inhibitors were also analyzed. Average pre-LDL-C was 109.5 mg/dL [CI: 15.8] while post-LDL-C was 39.8 mg/dL [CI: 17.2], which revealed a 64% decrease in LDL-C levels. The main reason for discontinuation of Inclisiran was insurance denial followed by individual preference. Only one subject discontinued Inclisiran due to experiencing a generalized rash. Conclusions: Inclisiran is an effective and overall well-tolerated medication indicated for the management of elevated LDL cholesterol. Our study revealed that for individuals with above goal LDL-C, despite maximum tolerated therapy with a statin, additional LDL-C lowering benefits can be seen with Inclisiran use. However, insurance approval and cost burden seem to be the main barriers for access. Presentation: 6/3/2024

Cost-Utility Analysis of PCSK9 Inhibitors and Quality of Life: A Two-Year Multicenter Non-Randomized Study.

The primary objective of this study was to conduct a cost-utility analysis of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors in real-world, comparing their use with standard care for managing cardiovascular disease. A multicenter prospective study was conducted across 12 Spanish hospitals from May 2020 to April 2022, involving 158 patients with hypercholesterolemia or atherosclerotic cardiovascular disease. This study assessed health-related quality of life (QoL) using the EQ-5D-3L questionnaire. The cost-utility analysis evaluated the economic impact of PCSK9 inhibitors when used with standard care compared to standard care alone, calculating the incremental cost-effectiveness ratio (ICER). This study included 158 patients with an average age of 61 years, male (66.5%). For patients initiating PCSK9 inhibitors, the treatment cost was EUR 13,633.39, while standard therapy cost EUR 3638.25 over two years. QoL for PCSK9 inhibitors stood at 1.6489 over two years, compared to 1.4548 for standard therapy. The results revealed favorable cost-utility outcomes, with an ICER of EUR 51,427.72. Significant improvements were observed in the domains of mobility, self-care, daily activities, pain/discomfort, and anxiety/depression (p < 0.001). This study presents the first real-world cost-utility analysis of PCSK9 inhibitors, supporting their economic rationale and highlighting their benefits in clinical practice. Healthcare decision-makers can use these results to inform their decisions and reimbursement policies concerning PCSK9 inhibitors. Trial Registration clinicaltrials.gov Identifier: NCT04319081.

PCSK9 inhibitor attenuates cardiac fibrosis in reperfusion injury rat by suppressing inflammatory response and TGF-β1/Smad3 pathway

Progressive cardiac fibrosis, a hallmark of heart failure, remains poorly understood regarding Proprotein convertase subtilisin/kexin type 9 (PCSK9) ’s role. This study aims to elucidate PCSK9′s involvement in cardiac fibrosis. After ischemia/reperfusion (I/R) injury surgery in rats, PCSK9 inhibitors were used to examine their effects on the transforming growth factor-β1 (TGF-β1)/small mother against decapentaplegic 3 (Smad3) pathway and inflammation. Elevated PCSK9, TGF-β1, and Smad3 levels were observed in cardiac tissues post-I/R injury, indicating fibrosis. PCSK9 inhibition reduced pro-fibrotic protein expression, protecting the heart and mitigating I/R-induced damage and fibrosis. Additionally, it ameliorated cardiac inflammation and reduced post-myocardial infarction (MI) size, improving cardiac function and slowing heart failure progression. PCSK9 inhibitors significantly attenuate myocardial fibrosis induced by I/R via the TGF-β1/Smad3 pathway.

Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitor Eligibility and Prescription Rates in Patients Presenting With Recurrent Acute Coronary Syndromes

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are novel medications for reducing low-density lipoprotein cholesterol (LDL-C) levels. In 2020, the Australian Pharmaceutical Benefits Scheme (PBS) began subsidising PCSK9 inhibitors for secondary prevention of cardiovascular disease in patients with LDL-C >2.6 mmol/L despite statin and ezetimibe therapy. This criterion was expanded to LDL-C >1.8 mmol/L in2022. A retrospective analysis was conducted on patients admitted to a quaternary hospital with acute coronary syndrome (ACS) between 2020-2022. PCSK9 inhibitor eligibility and prescribing patterns were compared between recurrent ACS patients (≥2 events within 5 years) and first-presentation ACS patients. Australian PBS 2020 and 2022 criteria were applied to assess eligibility. Of 817 ACS patients with LDL-C >1.8 mmol/L, 118 (14.4%) were categorised as recurrent ACS (33.9% female, mean age 67 years, LDL-C 2.9 mmol/L). When compared with first-presentation ACS patients (n=699), recurrent ACS patients had significantly higher proportions already on statin therapy (49.2% vs 6.0%, p<0.001) and ezetimibe (20.3% vs 2.4%, p<0.001). Recurrent ACS patients had significantly higher proportions of 2020 PBS-eligible patients (11.0% vs 1.3%, p<0.001) and 2022 PBS-eligible patients (20.3% vs 2.2%, p<0.001). There were no significant differences in PCSK9 inhibitor prescription rates among eligible patients (four of 13, 30.8% vs four of nine, 44.4%, p=0.51). Univariate binary logistic regression demonstrated that statin intolerance was significantly associated with PCSK9 inhibitor prescription (odds ratio 10; 95% confidence interval 1.3-79.3; p=0.029). Despite significantly higher eligibility rates, PCSK9 inhibitor uptake remains low in recurrent ACS patients, demonstrating the need to raise further awareness about eligibility criteria and encourage proactive prescription to prevent recurrent cardiovascular events.

Normal caloric intake with high-fat diet induces metabolic dysfunction-associated steatotic liver disease and dyslipidemia without obesity in rats

Excessive caloric intake and obesity due to high-fat (HFD) and high-disaccharide (HDD) diets have been recognized as major contributing factors to dyslipidemia and metabolic dysfunction-associated steatotic liver disease (MASLD). However, the effect of HFD and HDD without excessive caloric intake is obscure. The aim of the study was to evaluate the effect of physiological caloric intake delivered through HFD and HDD on liver and lipid profiles. The study was performed on 6-week-old male and female (50/50%) Sprague Dawley rats, receiving either a standard (controls, n = 16), HFD (n = 14) or HDD (n = 14) chow. All groups received the same, standard daily calorie rations, titrated weekly to the age of growing rats, for 12 weeks. A panel of metabolic in vivo measurement were performed, followed by histological, biochemical and molecular biology assays on tissues harvested from sacrificed rats. There was no significant difference between the groups in body weight. In contrast to controls, HFD and HDD groups showed metabolic dysfunction-associated steatohepatitis (MASH) characterized by liver steatosis, inflammation, ballooning of hepatocytes and fibrosis. These changes were more pronounced in the HFD than in the HDD group. The HFD group showed significantly higher serum LDL than controls or HDD rats. Furthermore, the HFD group had higher liver protein levels of low-density lipoprotein receptor (LDLR) but lower plasma levels of proprotein convertase subtilisin/kexin type 9 (PCSK9) than the controls or HDD group. There were no differences between sexes in evaluated parameters. The excessive caloric intake and obesity are not prerequisites for the development of MASH and dyslipidemia in rats. The liver changes induced by the HFD and HDD diets exhibit differences in severity, as well as in the expression patterns of LDLR and PCSK9. Notably, these effects are independent of the sex of the rats.

Optimization of Hypercholesterolemia Treatment after Heart Transplant: The Role of PCSK9 Inhibitors.

Previous studies have reported the benefit of statins after heart transplant (HT). However, the use of high-dose statins might be limited in some HT patients due to intolerance and interactions with immunosuppression or might not be enough to achieve low-density lipoprotein (LDL) cholesterol goals. Hyperlipidemia has been associated with coronary allograft vasculopathy. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors might be a safe and effective option in HT patients with suboptimal lipid control. In a retrospective study, we identified HT patients in our center with LDL cholesterol >100 mg/dL, after diet modifications and up-titration of statins to maximum tolerated dose, treated with PCSK9i. The primary endpoint was LDL reduction one month after, and secondary endpoints were the development of donorspecific HLA antibodies (DSA) and the presence of coronary allograft vasculopathy or rejection. From January, 2018, to January, 2024, we identified five HT patients treated with PCSK9 inhibitors. In all cases, evolocumab was used. A significant reduction in LDL cholesterol was observed (151.6 ± 13.5 mg/dl to 72.4 ± 14.6 mg/dl; p = 0.04, mean reduction 75.7 ± 14.1 mg/dl), as well as in total cholesterol (231 ± 34.6 mg/dl to 152.2 ± 38.9 mg/dl; p < 0.01, mean reduction 78.8 ± 22.2 mg/dl). A significant increase in HDL cholesterol was not observed (45.4 ± 10.9 mg/dl to 46.2 ± 11.1 mg/dl; p = 0.60). One patient developed DSA five years after treatment onset. Rejection and coronary allograft vasculopathy were not observed. PCSK9 inhibitors are safe and effective in reducing LDL in HT patients. However, larger studies are needed to clarify if they can reduce the development of coronary allograft vasculopathy.

Dendrobium Officinale Kimura &amp; Migo Attenuates High Cholesterol Diet-Induced Atherosclerosis

Objectives: This study aimed to investigate the potential of Dendrobium officinale Kimura &amp; Migo (DOKM) in ameliorating high cholesterol-induced atherosclerosis (AS) in zebrafish, focusing on the development of safe and effective drugs with low toxicity for AS treatment. Methods: A zebrafish AS model was established by feeding zebrafish a high cholesterol diet (HCD). Treatment was administered using 1 mg/L and 10 mg/L DOKM water extract. Fluorescence microscopy was utilised to observe the effects of DOKM on HCD-induced cholesterol accumulation, neutrophil accumulation, and macrophage infiltration in the vasculature. The impact of DOKM on HCD-induced disorders of lipid metabolism was assessed using Nile red staining. Total cholesterol (TC), triglycerides (TG), and low-density lipoprotein (LDL-C) levels in zebrafish were measured using kits. The expression of pcsk9, srebf2, and hmgcr genes in zebrafish was determined using RT-PCR. HE staining and Elvitegravir (EVG) staining were employed to assess the effect of DOKM on plaque formation in the blood vessels of AS zebrafish. Results: A total of 145 compounds were collected from Dendrobium officinale, along with 680 corresponding targets. Additionally, 1583 atherosclerosis-related targets were identified, with 202 representing interaction targets between Dendrobium officinale and atherosclerosis-related targets. Key compounds identified included Gigantol, Chrysotobibenzyl, Naringenin Chalcone, Hesperetin, and Tangeretin. The core targets of Dendrobium officinale for atherosclerosis treatment were STAT3, PTPN11, JAK2, epidermal growth factor receptor (EGFR), platelet-derived growth factor receptor alpha (PDGFRA), proto-oncogene tyrosine-protein kinase Src (SRC), STAT1, TP53, ESR1, and AKT1. GO functional enrichment analysis revealed a total of 2090 GO biological functional entries. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis showed 200 AS signalling pathways associated with DOKM treatment for atherosclerosis. DOKM significantly attenuated cholesterol accumulation, neutrophil aggregation, and macrophage infiltration in the blood vessels of AS zebrafish, ultimately leading to reduced plaque formation. AS zebrafish exhibited lipid metabolism disorders, characterised by significant increases in TC, TG, and LDL-C levels, as well as mRNA expression of pcsk9, srebf2, and hmgcr genes. Treatment with DOKM significantly improved these lipid metabolism disorders. Conclusion: DOKM effectively attenuates HCD-induced AS, and this therapeutic effect on AS may be related to its role in improving lipid metabolism dysfunction.