Recent developments in pharmacotherapy for hypertriglyceridemia: what’s the current state of the art?

Hypertriglyceridemia Therapy: Past, Present and Future Perspectives

Hypertriglyceridemia therapy is essential for preventing cardiovascular diseases. Fibrates belong to an important class of lipid-lowering drugs useful for the management of dyslipidaemia. By acting on the peroxisome proliferator-activated receptor (PPAR)-α, these drugs lower serum triglyceride levels and raise high-density lipoprotein cholesterol. Fibrate monotherapy is associated with a risk of myopathy and this risk is enhanced when these agents are administered together with statins. However, whereas gemfibrozil can increase plasma concentrations of statins, fenofibrate has less influence on the pharmacokinetics of statins. Pemafibrate is a new PPAR-α-selective drug considered for therapy, and clinical trials are ongoing. Apart from this class of drugs, new therapies have emerged with different mechanisms of action to reduce triglycerides and the risk of cardiovascular diseases.

Recent Treatment Strategies for Acute Pancreatitis

Acute pancreatitis (AP) is a leading gastrointestinal disease that causes hospitalization. Initial management in the first 72 h after the diagnosis of AP is pivotal, which can influence the clinical outcomes of the disease. Initial management, including assessment of disease severity, fluid resuscitation, pain control, nutritional support, antibiotic use, and endoscopic retrograde cholangiopancreatography (ERCP) in gallstone pancreatitis, plays a fundamental role in AP treatment. Recent updates for fluid resuscitation, including treatment goals, the type, rate, volume, and duration, have triggered a paradigm shift from aggressive hydration with normal saline to goal-directed and non-aggressive hydration with lactated Ringer's solution. Evidence of the clinical benefit of early enteral feeding is becoming definitive. The routine use of prophylactic antibiotics is generally limited, and the procalcitonin-based algorithm of antibiotic use has recently been investigated to distinguish between inflammation and infection in patients with AP. Although urgent ERCP (within 24 h) should be performed for patients with gallstone pancreatitis and cholangitis, urgent ERCP is not indicated in patients without cholangitis. The management approach for patients with local complications of AP, particularly those with infected necrotizing pancreatitis, is discussed in detail, including indications, timing, anatomical considerations, and selection of intervention methods. Furthermore, convalescent treatment, including cholecystectomy in gallstone pancreatitis, lipid-lowering medications in hypertriglyceridemia-induced AP, and alcohol intervention in alcoholic pancreatitis, is also important for improving the prognosis and preventing recurrence in patients with AP. This review focuses on recent updates on the initial and convalescent management strategies for AP.

Differentially Expressed Genes in Response to a Squalene-Supplemented Diet Are Accurate Discriminants of Porcine Non-Alcoholic Steatohepatitis

Squalene is the major unsaponifiable component of virgin olive oil, the fat source of the Mediterranean diet. To evaluate its effect on the hepatic transcriptome, RNA sequencing was carried out in two groups of male Large White x Landrace pigs developing nonalcoholic steatohepatitis by feeding them a high fat/cholesterol/fructose and methionine and choline-deficient steatotic diet or the same diet with 0.5% squalene. Hepatic lipids, squalene content, steatosis, activity (ballooning + inflammation), and SAF (steatosis + activity + fibrosis) scores were analyzed. Pigs receiving the latter diet showed hepatic squalene accumulation and twelve significantly differentially expressed hepatic genes (log2 fold change < 1.5 or <1.5) correlating in a gene network. These pigs also had lower hepatic triglycerides and lipid droplet areas and higher cellular ballooning. Glutamyl aminopeptidase (ENPEP) was correlated with triglyceride content, while alpha-fetoprotein (AFP), neutralized E3 ubiquitin protein ligase 3 (NEURL3), 2'-5'-oligoadenylate synthase-like protein (OASL), and protein phosphatase 1 regulatory inhibitor subunit 1B (PPP1R1B) were correlated with activity reflecting inflammation and ballooning, and NEURL3 with the SAF score. AFP, ENPEP, and PPP1R1B exhibited a remarkably strong discriminant power compared to those pathological parameters in both experimental groups. Moreover, the expression of PPP1R1B, TMEM45B, AFP, and ENPEP followed the same pattern in vitro using human hepatoma (HEPG2) and mouse liver 12 (AML12) cell lines incubated with squalene, indicating a direct effect of squalene on these expressions. These findings suggest that squalene accumulated in the liver is able to modulate gene expression changes that may influence the progression of non-alcoholic steatohepatitis.

Medical management of hypertriglyceridemia in pancreatitis

PURPOSE OF REVIEW

Hypertriglyceridemia-induced acute pancreatitis (HTG-AP) should be considered in all cases of acute pancreatitis and triglyceride levels measured early, so that appropriate early and long-term treatment can be initiated.

RECENT FINDINGS

In most cases of HTG-AP, conservative management (nothing by mouth, intravenous fluid resuscitation and analgesia) is sufficient to achieve triglyceride levels less than 500 mg/dl. Intravenous insulin and plasmapheresis are sometimes used, although prospective studies showing clinical benefits are lacking. Pharmacological management of hypertriglyceridemia (HTG) should start early and target triglyceride levels of less than 500 mg/dl to reduce the risk or recurrent acute pancreatitis. In addition to currently used fenofibrate and omega-3 fatty acids, several novel agents are being studied for long-term treatment of HTG. These emerging therapies focus mainly on modifying the action of lipoprotein lipase (LPL) through inhibition of apolipoprotein CIII and angiopoietin-like protein 3. Dietary modifications and avoidance of secondary factors that worsen triglyceride levels should also be pursued. In some cases of HTG-AP, genetic testing may help personalize management and improve outcomes.

SUMMARY

Patients with HTG-AP require acute and long-term management of HTG with the goal of reducing and maintaining triglyceride levels to less than 500 mg/dl.

New Therapies for Primary Hyperlipidemia

Primary hyperlipidemias include a heterogeneous set of monogenic and polygenic conditions characterized by a strong family aggregation, severe forms of hypercholesterolemia and/or hypertriglyceridemia, appearance early on life, and a high risk of cardiovascular events and/or recurrent pancreatitis. In real life, a small proportion of the primary hyperlipidemia cases is recognized and treated properly. Our goal is to present an update of current and upcoming therapies for patients with primary hyperlipidemia. Recently, new lipid-lowering medications have obtained authorization from the U.S. Food and Drug Administration and the European Medicines Agency. These drugs target metabolic pathways, including (adenosine 5'-triphosphates)-citrate lyase (bempedoic acid), proprotein convertase subtilisin/kexin 9 (inclisiran), apolipoprotein CIII (volanesorsen), and angiopoietin-like 3 (volanesorsen), that have additive effects with the actions of the currently available therapies (i.e., statins, ezetimibe or fibrates). We discuss the potential clinical indications for the novel medications. To conclude, the addition of these new medications to the therapeutic options for primary hyperlipidemia patients may increase the likelihood of achieving the treatment targets. Also, it could be a safer alternative for patients with side effects for the currently available drugs.

Early Investigational and Experimental Therapeutics for the Treatment of Hypertriglyceridemia

Hypertriglyceridemia has been identified as a risk factor for cardiovascular disease and acute pancreatitis. To date, there are only few drug classes targeting triglyceride levels such as fibrates and ω-3 fatty acids. These agents are at times insufficient to address very high triglycerides and the residual cardiovascular risk in patients with mixed dyslipidemia. To address this unmet clinical need, novel triglyceride-lowering agents have been in different phases of early clinical development. In this review, the latest and experimental therapies for the management of hypertriglyceridemia are presented. Specifically, ongoing trials evaluating novel apolipoprotein C-III inhibitors, ω-3 fatty acids, as well as fibroblast growth 21 analogues are discussed.

Treatment of Hypertriglyceridemia: A Review of Therapies in the Pipeline

BackgroundThe 2018 American College of Cardiology/American Heart Association (ACC/AHA) guidelines and 2021 ACC Expert Consensus Decision Pathway recommend nonpharmacological interventions and initiation of statin therapy for patients with moderate hypertriglyceridemia and addition of fibrates or omega-3 fatty acids in severe hypertriglyceridemia. Although the association between triglyceride (TG) lowering and atherosclerotic cardiovascular disease (ASCVD) risk reduction remains controversial, patients with hypertriglyceridemia may represent a subgroup that require additional therapy to further reduce residual ASCVD risk. Moreover, medications that target novel pathways could provide alternative options for patients who are intolerant of existing therapies or doses needed to provide adequate triglyceride lowering. Objective: Assess recent evidence for TG-lowering agents including omega-3 fatty acid-based therapies, PPARα modulators, apoC-III mRNA antisense inhibitors, angiopoietin-like 3 (ANGPTL3) antibodies, and herbal supplements. Methods: A literature search was performed using PubMed with hypertriglyceridemia specified as a MeSH term or included in the title or abstract of the article along with each individual agent. For inclusion, trials needed to have a primary or secondary outcome of TG levels or TG lowering. Conclusion: Currently, the only US Food and Drug Administration approved medication for CV risk reduction in patients with hypertriglyceridemia is icosapent ethyl. Results from phase 3 trials for CaPre, pemafibrate, and volanesorsen as well as additional evidence for pipeline pharmacotherapies with novel mechanisms of action (e.g., ApoC-III mRNA antisense inhibitors and ANGPTL3 antibodies) will help to guide future pharmacotherapy considerations for patients with hypertriglyceridemia.

Treatment of mild-to-moderate hypertriglyceridemia

The atherogenic role of triglycerides (TG) as an independent cardiovascular risk factor has been discussed for many years, largely because hypertriglyceridaemia (HTG) is a complex metabolic entity of multiple aetiology involving processes of diverse nature. In this chapter, a discussion will be presented on the current recommendations for the management of mild-moderate hypertriglyceridaemia (150-880mg/dL). The aim of the interventions used is to decrease the LDL-cholesterol (c-LDL) and control the HTG. This entails reducing apoprotein B (ApoB) levels, the number of remaining TG-rich lipoproteins (LRP), non-HDL-cholesterol (c-non-HDL), and increasing HDL-cholesterol (c-HDL). The management strategy includes healthy lifestyle recommendations, and subsequent use of lipid-lowering drugs, including statins, fibrates, n-3 fatty acids and PCSK9 inhibitors.

Hypertriglyceridemia and acute pancreatitis

Hypertriglyceridemia is the third most common cause of acute pancreatitis. It typically occurs in patients with an underlying disorder of lipoprotein metabolism and in the presence of a secondary condition such as uncontrolled diabetes, alcohol abuse, or medication use. The presentation of hypertriglyceridemia-induced pancreatitis is similar to that of acute pancreatitis due to other causes; however, patients with hypertriglyceridemia-induced pancreatitis are more likely to have severe disease courses and have a higher likelihood of persistent organ failure. The initial treatment of hypertriglyceridemia-induced pancreatitis is also similar to acute pancreatitis from other causes and consists of aggressive fluid resuscitation, pain control, and nutritional support. Hypertriglyceridemia is specifically treated with apheresis or insulin therapy when necessary. The prompt recognition of hypertriglyceridemia in the setting of acute pancreatitis is essential in both the initial and long-term management of this disease and are essential to prevent recurrent acute pancreatitis. The review seeks to highlight the etiology, pathogenesis, and clinical course of hypertriglyceridemia-induced acute pancreatitis.

Remnant lipoproteins: are they equal to or more atherogenic than LDL?

PURPOSE OF REVIEW

To critically appraise new insights into the biology of remnant lipoproteins and their putative role in the pathophysiology of atherosclerotic cardiovascular disease, and to compare the atherogenicity of remnant particles with that of low-density lipoproteins (LDL).

RECENT FINDINGS

New in-vivo stable isotope tracer studies of the kinetics of apoB48 and apoB100-containing lipoproteins in postprandial conditions have revealed that apoB48-containing very low-density lipoproteins (VLDL) accumulated markedly in hypertriglyceridemic patients. These intestinally-derived particles were cleared slowly, and represented up to 25% of circulating VLDL; as part of the remnant particle population, they may increase cardiovascular risk. Importantly, the PCSK9 inhibitor, evolocumab, was shown to reduce remnant levels (-29%) during the postprandial period in diabetic patients on statin therapy - an effect which may be additive to that of LDL-cholesterol reduction in conferring cardiovascular benefit. In recent Mendelian randomization studies, the effect of lowering triglyceride-rich lipoproteins or LDL-cholesterol translated to similar clinical benefit per unit of apoB. Finally, in randomized trials involving statin-treated patients with atherosclerotic cardiovascular disease, remnant cholesterol levels were associated with coronary atheroma progression independently of LDL-cholesterol.

SUMMARY

Overall, data from observational studies in large cohorts, Mendelian randomization studies, meta-regression analyses, and post-hoc analyses of randomized trials are consistent with the contention that remnants are highly atherogenic particles and contribute to the atherosclerotic burden in an equivalent manner to that of LDL.