Lipoproteins and cancer: The role of HDL-C, LDL-C, and cholesterol-lowering drugs.

Cholesterol is an amphipathic sterol molecule that is vital for maintaining normal physiological homeostasis. It is a relatively complicated molecule with 27 carbons whose synthesis starts with 2-carbon units. This in itself signifies the importance of this molecule. Cholesterol serves as a precursor for vitamin D, bile acids, and hormones, including estrogens, androgens, progestogens, and corticosteroids. Although essential, high cholesterol levels are associated with cardiovascular and kidney diseases and cancer initiation, progression, and metastasis. Although there are some contrary reports, current literature suggests a positive association between serum cholesterol levels and the risk and extent of cancer development. In this review, we first present a brief overview of cholesterol biosynthesis and its transport, then elucidate the role of cholesterol in the progression of some cancers. Suggested mechanisms for cholesterol-mediated cancer progression are plentiful and include the activation of oncogenic signaling pathways and the induction of oxidative stress, among others. The specific roles of the lipoprotein molecules, high-density lipoprotein (HDL) and low-density lipoprotein (LDL), in this pathogenesis, are also reviewed. Finally, we hone on the potential role of some cholesterol-lowering medications in cancer.

Effectiveness of Blood Lipid Management in Patients With Peripheral Artery Disease.

BACKGROUND: Low-density lipoprotein cholesterol (LDL-C) is associated with heightened risk of major adverse cardiovascular events (MACE) and major adverse limb events (MALE) in peripheral artery disease (PAD). Lipid-lowering therapies (LLT) that reduce LDL-C decrease this risk. OBJECTIVES: The authors examined LLT use and actual achieved LDL-C in PAD. METHODS: PAD patients in MarketScan from 2014 to 2018 were identified. Outcomes included LLT use, defined as high-intensity (HI) (high-intensity statin, statin plus ezetimibe, or PCSK9 inhibitor), low-intensity (any other lipid regimen), or no therapy, and follow-up LDL-C. Factors associated with LDL-C <70 mg/dl were identified with multivariable logistic regression. RESULTS: Among 250,103 PAD patients, 20.5% and 39.5% were treated at baseline with HI and low-intensity LLT, respectively; 40.0% were on no LLT. Over a 15-month median follow-up period, HI LLT use increased by 1.5%. Among 18,747 patients with LDL-C data, at baseline, 25.1% were on HI LLT, median LDL-C was 91 mg/dl, and 24.5% had LDL-C <70 mg/dl. Within the HI LLT subgroup, median LDL-C was 81 mg/dl, and 64% had LDL-C ≥70 mg/dl. At follow-up, HI LLT use increased by 3.7%, median LDL-C decreased by 4.0 mg/dl, and an additional 4.1% of patients had LDL-C <70 mg/dl. HI LLT use was greater after follow-up MACE (55.0%) or MALE (41.0%) versus no ischemic event (26.1%). After MACE or MALE, LDL-C was <70 mg/dl in 41.5% and 36.1% of patients, respectively, versus 27.1% in those without an event. Factors associated with follow-up LDL-C <70 mg/dl included smoking, hypertension, diabetes, prior lower extremity revascularization, and prior myocardial infarction but not prior acute or critical limb ischemia. CONCLUSIONS: In PAD, LLT use is suboptimal, LDL-C remains elevated, and LLT intensity is a poor surrogate for achieved LDL-C. Less aggressive lipid management was observed in PAD versus cardiovascular disease, highlighting missed opportunities for implementation of proven therapies in PAD.

Efficacy of PCSK9 inhibitors in the treatment of heterozygous familial hypercholesterolemia: A clinical practice experience.

BACKGROUND: PCSK9 inhibitors are a treatment option for patients with familial hypercholesterolemia not on low-density lipoprotein cholesterol goals despite the use of maximally tolerated high intensity-statins dose. OBJECTIVE: To evaluate the efficacy of alirocumab and evolocumab in LDL-C reduction and targets attainment in patients with heterozygous familial hypercholesterolemia in clinical practice setting. METHODS: SAFEHEART is an open, long-term prospective study of a cohort of subjects with molecular diagnosis of familial hypercholesterolemia. This study analyze subjects ≥ 20 years of age on stable lipid-lowering therapy, who received PCSK9 inhibitors during the period 2016 to January 2020. RESULTS: 433 patients (mean age 55 years, 53% male, 39% with cardiovascular disease) were included and followed-up for a median of 2.5 years (IQR 1.6-3.0). Median LDL-C level prior to PCSK9 inhibitors was 145 mg/dL (IQR 125-173). The addition of PCSK9 inhibitors (211 alirocumab, 222 evolocumab) reduced LDL-C by 58% (IQR 41-70) p<0.001, in men and women, achieving a median LDL-C level of 62 mg/dL (IQR 44-87) without differences between both PCSK9 inhibitors. Out of them 67% with and 80% without cardiovascular disease reached 2016 ESC/EAS LDL-C targets, and 46% very high risk and 50% high risk patients achieved 2019 ESC/EAS LDL-C goals. Independent predictor factors for attainment of 2019 ESC/EAS LDL-C goals were to be male, smoking and the use of statins with ezetimibe. Both inhibitors were well tolerated. CONCLUSIONS: PCSK9 inhibitors on top of maximum lipid-lowering treatment significantly reduced LDL-C levels in patients with familial hypercholesterolemia and improved the achievement of LDL-C targets.

Using genetic variants to evaluate the causal effect of cholesterol lowering on head and neck cancer risk: A Mendelian randomization study.

Head and neck squamous cell carcinoma (HNSCC), which includes cancers of the oral cavity and oropharynx, is a cause of substantial global morbidity and mortality. Strategies to reduce disease burden include discovery of novel therapies and repurposing of existing drugs. Statins are commonly prescribed for lowering circulating cholesterol by inhibiting HMG-CoA reductase (HMGCR). Results from some observational studies suggest that statin use may reduce HNSCC risk. We appraised the relationship of genetically-proxied cholesterol-lowering drug targets and other circulating lipid traits with oral (OC) and oropharyngeal (OPC) cancer risk using two-sample Mendelian randomization (MR). For the primary analysis, germline genetic variants in HMGCR, NPC1L1, CETP, PCSK9 and LDLR were used to proxy the effect of low-density lipoprotein cholesterol (LDL-C) lowering therapies. In secondary analyses, variants were used to proxy circulating levels of other lipid traits in a genome-wide association study (GWAS) meta-analysis of 188,578 individuals. Both primary and secondary analyses aimed to estimate the downstream causal effect of cholesterol lowering therapies on OC and OPC risk. The second sample for MR was taken from a GWAS of 6,034 OC and OPC cases and 6,585 controls (GAME-ON). Analyses were replicated in UK Biobank, using 839 OC and OPC cases and 372,016 controls and the results of the GAME-ON and UK Biobank analyses combined in a fixed-effects meta-analysis. We found limited evidence of a causal effect of genetically-proxied LDL-C lowering using HMGCR, NPC1L1, CETP or other circulating lipid traits on either OC or OPC risk. Genetically-proxied PCSK9 inhibition equivalent to a 1 mmol/L (38.7 mg/dL) reduction in LDL-C was associated with an increased risk of OC and OPC combined (OR 1.8 95%CI 1.2, 2.8, p = 9.31 x10-05), with good concordance between GAME-ON and UK Biobank (I2 = 22%). Effects for PCSK9 appeared stronger in relation to OPC (OR 2.6 95%CI 1.4, 4.9) than OC (OR 1.4 95%CI 0.8, 2.4). LDLR variants, resulting in genetically-proxied reduction in LDL-C equivalent to a 1 mmol/L (38.7 mg/dL), reduced the risk of OC and OPC combined (OR 0.7, 95%CI 0.5, 1.0, p = 0.006). A series of pleiotropy-robust and outlier detection methods showed that pleiotropy did not bias our findings. We found limited evidence for a role of cholesterol-lowering in OC and OPC risk, suggesting previous observational results may have been confounded. There was some evidence that genetically-proxied inhibition of PCSK9 increased risk, while lipid-lowering variants in LDLR, reduced risk of combined OC and OPC. This result suggests that the mechanisms of action of PCSK9 on OC and OPC risk may be independent of its cholesterol lowering effects; however, this was not supported uniformly across all sensitivity analyses and further replication of this finding is required.

Pooled Patient-Level Analysis of Inclisiran Trials in Patients With Familial Hypercholesterolemia or Atherosclerosis.

BACKGROUND: Inclisiran is a double-stranded small interfering RNA that suppresses proprotein convertase subtilisin-kexin type 9 (PCSK9) translation in the liver, leading to sustained reductions in low-density lipoprotein cholesterol (LDL-C) and other atherogenic lipoproteins with twice-yearly dosing. OBJECTIVES: The purpose of this study was to conduct a patient-level pooled analysis from 3 phase 3 studies of inclisiran. METHODS: Participants with heterozygous familial hypercholesterolemia (ORION-9 [Trial to Evaluate the Effect of Inclisiran Treatment on Low Density Lipoprotein Cholesterol (LDL-C) in Subjects With Heterozygous Familial Hypercholesterolemia (HeFH)]), atherosclerotic cardiovascular disease (ASCVD) (ORION-10 [Inclisiran for Participants With Atherosclerotic Cardiovascular Disease and Elevated Low-density Lipoprotein Cholesterol]), or ASCVD and ASCVD risk equivalents (ORION-11 [Inclisiran for Subjects With ASCVD or ASCVD-Risk Equivalents and Elevated Low-density Lipoprotein Cholesterol]) taking maximally tolerated statin therapy, with or without other LDL-C-lowering agents, were randomly assigned in a 1:1 ratio to receive either inclisiran or placebo, administered by subcutaneous injection on day 1, day 90, and every 6 months thereafter for 540 days. The coprimary endpoints were the placebo-corrected percentage change in LDL-C level from baseline to day 510 and the time-adjusted percentage change in LDL-C level from baseline after day 90 to day 540. Levels of other atherogenic lipoproteins and treatment-emergent adverse events were also assessed. RESULTS: A total of 3,660 participants (n = 482, n = 1,561, and n = 1,617 from ORION-9, -10, and -11, respectively) underwent randomization. The placebo-corrected change in LDL-C with inclisiran at day 510 was -50.7% (95% confidence interval: -52.9% to -48.4%; p < 0.0001). The corresponding time-adjusted change in LDL-C was -50.5% (95% confidence interval: -52.1% to -48.9%; p < 0.0001). Safety was similar in both groups. Treatment-emergent adverse events at the injection site were more frequent with inclisiran than placebo (5.0% vs. 0.7%), but were predominantly mild, and none were severe or persistent. Liver and kidney function tests, creatine kinase values, and platelet counts did not differ between groups. CONCLUSIONS: These pooled safety and efficacy data show that inclisiran, given twice yearly in addition to maximally tolerated statin therapy with or without other LDL-C lowering agents, is an effective, safe, and well-tolerated treatment to lower LDL-C in adults with heterozygous familial hypercholesterolemia, ASCVD, or ASCVD risk equivalents.

Assessment of exopolysaccharides, bacteriocins and in vitro and in vivo hypocholesterolemic potential of some Egyptian Lactobacillus spp.

Lactobacilli probiotics have been suggested to reduce cholesterol with low side effects to host. Bacteriocins and exopolysaccharides (EPSs) production are two meaningful examples of functional applications of lactobacilli in the food industry. Eight Lactobacillus strains were isolated from some Egyptian fermented food and tested for their probiotic properties. Analysis of the monosaccharide composition by thin layer chromatography showed the presence of glucose, galactose and unknown sugar. The main functional groups of EPSs were elucidated by Fourier-Transform Infrared Spectroscopy. Their fermentation cultures displayed powerful antioxidant activities extending from 97.5 to 99%, 40-75% for their EPSs and free cells, respectively, and exhibited in vitro cholesterol downgrading from 48 to 82% and 72 to 91% after 48 and 120 h, respectively. Their EPSs showed good anticancer activities against carcinoma cells with low IC50 values for HCT-116, PC-3 and HepG-2 cells. To the best of our knowledge, there have been no previous reports on the potential of Lactobacillus EPSs activity against PC-3. The selected strains, L. plantarum KU985433 and L. rhamnosus KU985436 produced two different bacteriocins as detected by gel permeation chromatography with good antimicrobial activities. In vivo study demonstrated that feeding Westar rats with fermented milk exhibited greater cholesterol, LDL and blood triglyceride reduction for both strains. Whereas, HDL was increased by about 43 and 38%, respectively, and the atherogenic indices decreased.

Identification of IgG1 isotype phosphorylcholine antibodies for the treatment of inflammatory cardiovascular diseases.

BACKGROUND: Phosphorylcholine (PC) is an important pro-inflammatory damage-associated molecular pattern. Previous data have shown that natural IgM anti-PC protects against cardiovascular disease. We aimed to develop a monoclonal PC IgG antibody with anti-inflammatory and anti-atherosclerotic properties. METHODS: Using various techniques PC antibodies were validated and optimized. In vivo testing was performed in a femoral artery cuff model in ApoE3*Leiden mice. Safety studies are performed in rats and cynomolgus monkeys. RESULTS: A chimeric anti-PC (PC-mAb(T15), consisting of a human IgG1 Fc and a mouse T15/E06 Fab) was produced, and this was shown to bind specifically to epitopes in human atherosclerotic tissues. The cuff model results in rapid induction of inflammatory genes and altered expression of genes associated with ER stress and choline metabolism in the lesions. Treatment with PC-mAb(T15) reduced accelerated atherosclerosis via reduced expression of endoplasmic reticulum stress markers and CCL2 production. Recombinant anti-PC Fab fragments were identified by phage display and cloned into fully human IgG1 backbones creating a human monoclonal IgG1 anti-PC (PC-mAbs) that specifically bind PC, apoptotic cells and oxLDL. Based on preventing macrophage oxLDL uptake and CCL2 production, four monoclonal PC-mAbs were selected, which to various extent reduced vascular inflammation and lesion development. Additional optimization and validation of two PC-mAb antibodies resulted in selection of PC-mAb X19-A05, which inhibited accelerated atherosclerosis. Clinical grade production of this antibody (ATH3G10) significantly attenuated vascular inflammation and accelerated atherosclerosis and was tolerated in safety studies in rats and cynomolgus monkeys. CONCLUSIONS: Chimeric anti-PCs can prevent accelerated atherosclerosis by inhibiting vascular inflammation directly and through reduced macrophage oxLDL uptake resulting in decreased lesions. PC-mAb represents a novel strategy for cardiovascular disease prevention.

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

BACKGROUND: 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. OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: Available evidence suggests similar potency of alirocumab and evolocumab in reducing lipids and CV events.

Impact of fibrates on circulating cystatin C levels: a systematic review and meta-analysis of clinical trials.

AIMS: To assess the effect of fibrates on circulating cystatin C levels. MATERIAL AND METHODS: Clinical studies evaluating the effect of a fibrate on circulating cystatin C levels were searched in PubMed-Medline, SCOPUS, Web of Science, and Google Scholar databases. A random-effect model and generic inverse variance method were used for quantitative data synthesis, sensitivity analysis conducted using the leave-one-out method, and weighted random-effects meta-regression performed to evaluate potential confounders on cystatin C levels. RESULTS: This meta-analysis of data from nine published studies (16 treatment arms) involved a total of 2195 subjects. In a single-arm analysis of clinical trials (without control group; eight studies comprising 14 treatment arms), fibrate therapy increased circulating cystatin C concentrations (WMD: 0.07 mg/dL, 95% CI: 0.04, 0.10, p < .001; I2 = 82.66%). When the analysis was restricted to randomized controlled trials (four studies comprising six treatment arms), again elevation of circulating cystatin C levels was observed (WMD: 0.06 mg/L, 95% CI: 0.03, 0.09, p < .001; I2 = 42.98%). Elevated cystatin C levels were only seen with fenofibrate and not with other fibrates. CONCLUSIONS: The results suggest that fenofibrate treatment adversely affects cystatin C levels and might partially explain the limited efficacy of fenofibrate in reducing cardiovascular events. Key message Fenofibrate treatment adversely affects cystatin C levels and might partially explain the limited efficacy of fenofibrate in reducing cardiovascular events.

Hypolipidemic, antioxidant and antiatherogenic property of sardine by-products proteins in high-fat diet induced obese rats.

AIMS: Fish by-products valorization on account of their richness in bioactive compounds may represent a better alternative to marine products with a view to economic profitability and sustainable development. In this study, we compared the effect of sardine by-product proteins (SBy-P), with those of the fillets (SF-P) or casein (Cas), on growth parameters, serum leptin level, lipids disorders, lipid peroxidation and reverse cholesterol transport, in diet-induced obese rats. MAIN METHODS: Obesity was induced by feeding rats a high-fat diet (20% sheep fat), during 12 weeks. At body weight (BW) of 400 ±â€¯20 g, eighteen obese rats were divided into three homogenous groups and continue to consume the high-fat diet for 4 weeks containing either, 20% SBy-P, SF-P or Cas. KEY FINDINGS: The results showed that SBy-P, compared to SF-P and Cas, efficiently reduced food intake (FI), BW gain and serum leptin level, and improved blood lipids levels and reverse cholesterol transport by reducing total cholesterol (TC), triacylglycerols (TG) and low-density lipoprotein cholesterol (LDL-HDL1-C) serum levels, increasing the level of high-density lipoprotein cholesterol (HDL2-C and HDL3-C), and enhancing lecithin: cholesterol acyltransferase (LCAT) activity. Furthermore, they attenuated lipid peroxidation by increasing atheroprotective activity of the paraoxonase-1 (PON-1). SIGNIFICANCE: Sardine by-product proteins due to their richness in certain essential amino acids, highlight weight-loss, lipid-lowering, antioxidant and anti-atherogenic potentials, contributing to the improvement of the complications associated with obesity.

Does Evolocumab, as a PCSK9 Inhibitor, Ameliorate the Lipid Profile in Familial Hypercholesterolemia Patients? A Meta-Analysis of Randomized Controlled Trials.

Proprotein convertase subtilisin-kexin type 9 (PCSK9) is a member of regulatory serine proteases which is mostly expressed in liver. In the physiological condition, LDL-C binds to LDL receptors (LDLRs) and via endocytosis, LDLRs are degraded. PCSK9 binds to the epidermal growth factor-like repeat A (EGFA) domain of extracellular LDLRs, and then physiological recycling of LDLRs from surface of liver is cancelled, resulting in elevation of circulating LDL-C in plasma. To evaluate whether evolucomab, as PCSK9 inhibitor monoclonal antibody, ameliorates lipid profile in familial hypercholesterolemia (FH) patients, this meta-analysis has been conducted. PubMed, Web of Science (ISI) and Scopus databases were searched for studies which had investigated the efficacy of evolucomab. Types of outcome investigated were percentage changes from baseline of the lipid profile. Our meta-analysis shows that evolucomab at the dosage of 420 mg monthly could decrease LDL-C  by 54.71%, TC by 35.08%, VLDL-C by 28.37 %, ratio of TC to HDL-C by 39.14 %, triglycerides by 12.11 %, and increased HDL-C by 6.06% from baseline compared to placebo at the end of study in FH patients. Our findings indicate that evolocumab could be a hopeful agent for challenging patients, such as statin intolerance or patients who fail to attain the target goal of LDL-C despite consumption of maximum doses of statins. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.

Pharmacogenomics of statin therapy: any new insights in efficacy or safety?

PURPOSE OF REVIEW: To examine the current evidence concerning the effects of genetic variation on statin-related low-density lipoprotein cholesterol reductions, clinical efficacy, and adverse events and the relevance for patient care. RECENT FINDINGS: Recent years have seen the emergence of large-scale genetic experiments, including genome-wide association studies and candidate gene studies, exploring the impact of common genetic variation on patient response to statins. These studies have built on previous smaller scale evidence, providing improved statistical power and enhanced ability to explore the genome. Current evidence suggests that common genetic variants do not alter low-density lipoprotein cholesterol response by more than a few percent, or materially alter the effect of statin on vascular risk reduction, and therefore that patients benefit from statins independent of common genetic variation. However, knowledge of SLCO1B1 genotypes is believed to have clinical utility for predicting myopathy risk and ensuring that statins are prescribed as safely as possible. Furthermore, new hypothesis-generating studies, such as those associating GATM with myopathy risk, offer potential insights for the future. SUMMARY: Common genetic variation does not appear to be an important determinant of statin response, with the exception of SLCO1B1 and risk of myopathy. Future studies will help to determine the impact of low-frequency and rare genetic variation on statin response.

Targeting LDL: is lower better and is it safe?

Low density lipoprotein cholesterol (LDL-C) is one of the most validated targets in clinical medicine. Large randomized, outcome trials have demonstrated a clear relationship between reducing LDL-C and cardiovascular disease (CVD) risk, which has been maintained to LDL-C levels of <1.8 mmol/L. To assess the benefit of even lower LDL-C it is important to recognize that CVD risk reduction is related to absolute reduction in LDL-C, not to percent change. Furthermore measurement of LDL-C is also critical as recent studies show the Friedewald calculation significantly underestimates true LDL-C values <1.8 mmol/L, distorting the relationship with CVD risk reduction. Discussion of potential harm from low, or lower, LDL-C has centered on cancer, hemorrhagic stroke, and violent death, but there is little evidence from outcome trials to show a relationship with low LDL-C. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors which will reduce LDL-C well below 1.3 mmol/L, will likely provide the clearest answer to both the question of efficacy and safety of low LDL-C within the next few years.

Comparative effectiveness of rosuvastatin versus simvastatin in primary prevention among new users: a cohort study in the French national health insurance database.

PURPOSE: Using the French claims database (Système National d'Information Inter-Régimes de l'Assurance Maladie) linked to the hospital discharge database (Programme de Médicalisation des Systèmes d'Information), this observational study compared the effectiveness of rosuvastatin and simvastatin prescribed at doses with close LDL-cholesterol-lowering potency on all-cause mortality and cardiovascular and cerebrovascular diseases (CCDs) in primary prevention. METHODS: This historical cohort included patients with no prior CCD, aged 40-79 years, who initiated statin therapy with rosuvastatin 5 mg or simvastatin 20 mg in 2008-2009 in general practice. Follow-up started after a 1-year period used to select patients who regularly received the initial treatment. In an intention-to-treat analysis, patients were followed up to December 2011. In a per-protocol analysis, they were censored prematurely when they discontinued their initial treatment. Adjustment for baseline covariates (age, deprivation index, comedications, comorbidities, prior hospital admissions) was carried out by a Cox proportional hazards model. In the per-protocol analysis, estimation was done by "inverse probability of censoring weighting" using additional time-dependent covariates. Analyses were gender-specific. RESULTS: A total of 106941 patients initiated statin therapy with rosuvastatin 5 mg and 56860 with simvastatin 20 mg. Mean follow-up was 35.8 months. For both genders and both types of analyses, the difference in incidence rates of mortality and/or CCD between rosuvastatin 5 mg and simvastatin 20 mg users was not statistically significant after adjustment (e.g., for CCD and/or mortality in men, in intention-to-treat analysis HR=0.94 [95% CI=0.85-1.04], in per-protocol analysis HR=0.98 [0.87-1.10]). CONCLUSIONS: The results of this real-life study based on medico-administrative databases do not support preferential prescription of rosuvastatin compared to simvastatin for primary prevention of CCD.

PCSK9 inhibitors.

PURPOSE OF REVIEW: To summarize the therapeutic strategies to inhibit PCSK9 and to describe the main results obtained in phase I and II trials with monoclonal antibodies targeting PCSK9. RECENT FINDINGS: Among the various approaches for PCSK9 inhibition, human data are only available for inhibition of PCSK9 binding to LDL receptor by monoclonal antibodies. Promising preclinical studies have also been reported with other strategies, including inhibition of PCSK9 synthesis by gene silencing agents. The two most advanced monoclonal antibodies in development are SAR236553/REGN727 and AMG145. In phase II, these two monoclonal antibodies administered subcutaneously are well tolerated and effective to decrease atherogenic lipoproteins. A dramatic decrease in LDL cholesterol up to 70% can be obtained. The efficacy has been evaluated so far in addition to statins in hypercholesterolemic patients with or without familial hypercholesterolemia, in patients with intolerance to statin therapy and in monotherapy. SUMMARY: The short-term efficacy, safety and tolerability of two monoclonal antibodies to PSCK9 have been demonstrated in several phase II trials. These PCSK9 inhibitors are now tested in larger phase III studies to provide insights into the long-term safety and clinical efficacy of this very promising approach.

Microsomal transfer protein inhibition in humans.

PURPOSE OF REVIEW: Microsomal triglyceride transfer protein (MTP) is a key protein in the secretion of apolipoprotein B-containing lipoproteins. Its pharmacological inhibition is associated with a decrease in LDL cholesterol (LDL-C) and triglycerides. However, the clinical use of MTP inhibitors has been uncertain because of the gastrointestinal adverse events and the increase in liver fat content observed during their administration. RECENT FINDINGS: Lomitapide, a systemic MTP inhibitor, significantly reduces LDL-C in homozygous familial hypercholesterolemia (hoFH) when administered concurrently with other lipid-lowering therapies, including apheresis. Its lipid-lowering effect is additive to that of existing drugs. In the presence of an up-titration regiment and low-fat diet, lomitapide is generally well tolerated and liver fat accumulation stabilizes after the initial increase. Elevation of alanine aminotranferase levels greater than 3 times the upper limit of normal can be managed successfully with temporary dose reduction. Drug-drug interaction studies show that concomitant treatment of lomitapide with other lipid-lowering drugs is generally safe. Based on these findings, lomitapide was recently approved for the treatment of hoFH as add-on therapy. SUMMARY: MTP inhibition is a valuable therapeutic approach for hoFH. Long-term safety consequences of liver fat accumulation will need to be assessed.

Mipomersen as a potential adjunctive therapy for hypercholesterolemia.

Mipomersen, an antisense oligonucleotide directed against apolipoprotein B-100 (apoB), was investigated for its safety and efficacy in reducing low-density lipoprotein (LDL) cholesterol (C) as adjunctive treatment for patients with homozygous familial hypercholesterolemia (HoFH) in a Phase III, double-blind, randomized, controlled trial. HoFH patients are very rare in the general population (∼ 1:1,000,000) and have very high risk for cardiovascular events. HoFH patients respond poorly to statins and most other existing lipid-lowering therapies. Mipomersen (200 or 160 mg) administered subcutaneously to 34 HoFH patients for 26 weeks significantly reduced LDL-C by 24.7% from baseline. In addition, mipomersen lowered plasma lipoprotein (a). In most patients, mipomersen administration was most associated with injection-site reactions; influenza-like symptoms were also more common in mipomersen-treated patients. Four patients had elevated serum alanine aminotransferase (ALT) concentrations, one of whom also had a significant increase in intrahepatic triglyceride content. Another patient met the stopping rules for increased ALT concentrations. No patient developed steatohepatitis during the study. Thus, so far short-term data indicate that mipomersen is safe and effective as an adjunctive drug for lowering LDL-C. Despite these promising results, the longer-term safety and efficacy of mipomersen still needs to be determined.