Contemporary and Novel Therapeutic Options for Hypertriglyceridemia

Exploring emerging pharmacotherapies for type 2 diabetes patients with hypertriglyceridemia

INTRODUCTION

Atherogenic dyslipidemia with increased triglycerides, low high-density lipoprotein cholesterol levels and increased small dense low-density lipoprotein (LDL) particles is a major risk factor contributing to the increased cardiovascular (CV) risk in patients with type 2 diabetes (T2D). This is regarded as a residual risk after achieving target levels of LDL cholesterol.

AREAS COVERED

This article reviews the novel therapies to reduce triglycerides in patients with T2D. These were identified by a PubMed search and mainly focus on pemafibrate and the drugs targeting apolipoprotein C3 (apoC3) and angiopoietin-like 3 (ANGPTL3).

EXPERT OPINION

Current therapies to reduce triglycerides in patients with T2D include fibrates and omega-3 fatty acids but these are often not sufficient and the evidence for CV benefits is limited. Pemafibrate was effective in reducing triglycerides in patients with T2D but did not reduce CV events in the PROMINENT study. Inhibitors of apoC3 are effective in reducing triglycerides even in familial chylomicronaemia syndrome and olezarsen and plozasiran in this group are being studied in patients with combined hyperlipidemia. The ANGPTL3 inhibitor evinacumab has been approved for homozygous familial hypercholesterolemia, and other ANGPTL3 inhibitors may prove to be useful to reduce triglycerides in T2D.

Olezarsen, a liver-directed APOC3 ASO therapy for hypertriglyceridemia

INTRODUCTION

Apolipoprotein (apo)C-III, a key regulator of plasma triglyceride (TG) levels, is a prime candidate for the treatment of hypertriglyceridemia (HTG), prevention of acute pancreatitis, and reduction of future atherosclerotic cardiovascular disease (ASCVD) events.

AREAS COVERED

We discuss the role of apoC-III as a therapeutic target for HTG, describe the pharmacodynamics, pharmacokinetics, and metabolism of olezarsen, as well as report on the findings of recent clinical trials with this liver-directed APOC3 antisense oligonucleotide (ASO).

EXPERT OPINION

Olezarsen, a GalNac-conjugated ASO targeting apoC-III, can reduce TG levels by ~ 50% in patients with extreme HTG due to familial chylomicronemia syndrome, as well as in patients with moderate HTG. Attention is now focused on whether olezarsen reduces ASCVD risk in patients with moderate and severe HTG. While olezarsen does cause elevations in liver enzymes, these changes are not clinically meaningful, and are not associated with thrombocytopenia, an issue with its predecessor, volanesorsen. The need for 4-weekly administration puts olezarsen at a disadvantage to competing injectables. Results from the CORE, CORE2, and ESSENCE phase III clinical trials in patients with severe HTG, expected in the second half of 2025, will help determine the requirement for a larger cardiovascular outcomes trial.

Hypertriglyceridemia-induced acute pancreatitis in children: A mini-review

Severe hypertriglyceridemia (HTG) is a known metabolic cause of acute pancreatitis (AP) in pediatric patients. The incidence of hypertriglyceridemia-induced acute pancreatitis (HTG-AP) is less well established in pediatric compared to adult patients. Studies in adults suggest that higher risk of AP occurs when triglyceride levels (TG) are >1,000 mg/dL. Most common etiologies for severe HTG in pediatric patients are either from primary hypertriglyceridemia, underlying genetic disorders of lipid and TG metabolism, or secondary hypertriglyceridemia, separate disease or exposure which affects TG metabolism. Most common theories for the pathophysiology of HTG-AP include hydrolysis of TG by pancreatic lipase to free fatty acids leading to endothelial and acinar cell damage and ischemia, as well as hyperviscosity related to increased chylomicrons. Though there are varying reports of HTG-AP severity compared to other causes of AP, a steadily growing body of evidence suggests that HTG-AP can be associated with more severe course and complications. Therapeutic interventions for HTG-AP typically involve inpatient management with dietary restriction, intravenous fluids, and insulin; select patients may require plasmapheresis. Long term interventions generally include dietary modification, weight management, control of secondary causes, and/or antihyperlipidemic medications. Though some therapeutic approaches and algorithms exist for adult patients, evidence-based management guidelines have not been well established for pediatric patients.

The characteristic, antioxidative and multiple organ protective of acidic-extractable mycelium polysaccharides by Pleurotus eryngii var. tuoliensis on high-fat emulsion induced-hypertriglyceridemic mice

The antioxidant and multiple organ protection effects of acid- extracted mycelia polysaccharides (Ac-MPS) from Pleurotus eryngii var. tuoliensis on HFE-induced hypertriglyceridemic mice were investigated. The results showed that Ac-MPS have potential ability to relieve the hypertriglyceridemia and preventing oxidative stress by decreasing levels of TG, TC LDL-C, elevating contents of HDL-C in serum, increasing the activities of SOD, GSH-Px, CAT and T-AOC, and the down regulating MDA and LPO contents in liver, heart, kidney and spleen. And the histopathological observations also displayed that Ac-MPS could alleviate organ damage. Moreover, the GC, HPGPC, FT-IR and AFM analyses revealed the Ac-MPS possessed the typical polysaccharides structure with the molecular weights (Mw) of 2.712 × 10⁵ Da. These conclusions indicated that the Ac-MPS had the potential to develop new drugs for hypertriglyceridemia-induced multiple organ failure.

Approach to Hypertriglyceridemia in the Pediatric Population

Hypertriglyceridemia is increasingly identified in children and adolescents, owing to improved screening and higher prevalence of childhood obesity. Hypertriglyceridemia can result from either increased triglyceride (TG) production or reduced TG clearance. The etiologic origin can be primary (genetic) or secondary, but it is often multifactorial. Management is challenging because of the interplay of genetic and secondary causes and lack of evidence-based guidelines. Lifestyle changes and dietary interventions are most important, especially in hypertriglyceridemia associated with obesity. Dietary restriction of fat remains the mainstay of management in primary hypertriglyceridemia. When fasting TG concentration is increased above 500 mg/dL (5.65 mmol/L), fibrates may be used to prevent pancreatitis. Omega-3 fatty acids are often used as an adjunctive therapy. When the fasting TG concentration is less than 500 mg/dL (5.65 mmol/L) and if the non-high-density lipoprotein cholesterol level is above 145 mg/dL (3.76 mmol/L), statin treatment can be considered.

Novel therapies for severe dyslipidemia originating from human genetics

PURPOSE OF REVIEW

Novel therapies for severe dyslipidemia target a wide range of unmet medical needs: severe familial hypercholesterolemia, severe hypertriglyceridemia and chylomicronemia, elevated lipoprotein (a), lipodystrophies, high-density lipoprotein particle diseases, lysosomal acid lipase deficiency and storage diseases, nonalcoholic fatty liver disease and others. The purpose of this review is to describe the contribution of human genetics to the development of therapeutic approaches targeting severe dyslipidemia.

RECENT FINDINGS

Recent advances in human genetics and the identification of rare genetic variants having strong effects on disease risk not only accelerated the development of therapies for severe dyslipidemia, they also revealed new pathways, genes and mechanisms of health, disease or drug response, and facilitated molecular diagnosis, which may prove essential as the authorized use of some of these novel drugs is limited to specific conditions. In addition, the dissection of the gene and cell machinery gave rise to new technologies, gene-based therapies and biodrugs covering a broad range of novel agents currently available or in clinical development to treat severe lipid disorders.

SUMMARY

Several novel therapies are recently available or under development to treat severe dyslipidemia and associated risk stem directly from genetic research. Altogether, these therapies target a broad variety of severe dyslipidemia pathways or mechanisms and illustrate that clinical lipidology has now entered the era of precision medicine.