Hypertriglyceridemic subjects exhibit an accumulation of small dense chylomicron particles in the fasting state

Efficacy and Safety of Pemafibrate Versus Bezafibrate to Treat Patients with Hypertriglyceridemia: A Randomized Crossover Study

AIM

Pemafibrate is a highly selective agonist for peroxisome proliferator-activated receptor (PPAR)-α, a key regulator of lipid and glucose metabolism. We compared the efficacy and safety of pemafibrate with those of bezafibrate, a nonselective PPAR-α agonist.

METHODS

In this randomized crossover study, 60 patients with hypertriglyceridemia (fasting triglyceride [TG] ≥ 150 mg/dL) were treated with pemafibrate of 0.2 mg/day or bezafibrate of 400 mg/day for 24 weeks. The primary endpoint was percent change (%Change) from baseline in TG levels, while the secondary endpoints were %Change in high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A-I (Apo A-I) levels.

RESULTS

The %Change in TG and Apo A-I levels was significantly greater with pemafibrate than with bezafibrate (-46.1% vs. -34.7%, p＜0.001; 9.2% vs. 5.7%, p =0.018, respectively). %Change in HDL-C levels was not significantly different between the two treatments. %Change in liver enzyme levels was markedly decreased with pemafibrate than with bezafibrate. Creatinine levels significantly increased in both treatments; however, its %Change was significantly lower with pemafibrate than with bezafibrate (5.72% vs. 15.5%, p＜0.001). The incidence of adverse events (AEs) or serious AEs did not differ between the two treatments; however, the number of patients with elevated creatinine levels (≥ 0.5 mg/dL and/or 25% from baseline) was significantly higher in the bezafibrate group than in the pemafibrate group (14/60 vs. 3/60, p =0.004) [corrected].

CONCLUSION

Compared with bezafibrate, pemafibrate is more effective in decreasing TG levels and increasing Apo A-I levels and is safer regarding liver and renal function.

Efficacy and safety of K-877, a novel selective peroxisome proliferator-activated receptor α modulator (SPPARMα), in combination with statin treatment: Two randomised, double-blind, placebo-controlled clinical trials in patients with dyslipidaemia

BACKGROUND AND AIMS

Substantial residual cardiovascular risks remain despite intensive statin treatment. Residual risks with high triglyceride and low high-density lipoprotein cholesterol are not the primary targets of statins. K-877 (pemafibrate) demonstrated robust efficacy on triglycerides and high-density lipoprotein cholesterol and a good safety profile as a monotherapy. The aim of these studies was to evaluate the efficacy and safety of K-877 add-on therapy to treat residual hypertriglyceridaemia during statin treatment.

METHODS

The objectives were investigated in two, multicentre, randomised, double-blind, placebo-controlled, parallel group comparison clinical trials: (A) K-877 0.1, 0.2, and 0.4 mg/day in combination with pitavastatin for 12 weeks in 188 patients, (B) K-877 0.2 (fixed dose) and 0.2 (0.4) (conditional up-titration) mg/day in combination with any statin for 24 weeks in 423 patients.

RESULTS

In both studies, we found a robust reduction in fasting triglyceride levels by approximately 50% in all combination therapy groups, which was significant compared to the statin-monotherapy (placebo) groups (p < 0.001). High-performance liquid chromatography analysis for lipoprotein subfractions revealed that atherogenic lipoprotein profiles were ameliorated by K-877 add-on therapy, i.e. small low-density lipoproteins decreased whereas larger ones increased, and larger high-density lipoproteins decreased whereas smaller ones increased. The incidence rates of adverse events and adverse drug reactions in K-877 combination therapy groups were comparable to those in statin-monotherapy groups without any noteworthy event in both studies.

CONCLUSIONS

These results strongly support the favourable benefit-to-risk ratio of K-877 add-on therapy in combination with statin treatment.

Dietary fat and physiological determinants of plasma chylomicron remnant homoeostasis in normolipidaemic subjects: insight into atherogenic risk

TAG depleted remnants of postprandial chylomicrons are a risk factor for atherosclerosis. Recent studies have demonstrated that in the fasted state, the majority of chylomicrons are small enough for transcytosis to arterial subendothelial space and accelerate atherogenesis. However, the size distribution of chylomicrons in the absorptive state is unclear. This study explored in normolipidaemic subjects the postprandial distribution of the chylomicron marker, apoB-48, in a TAG-rich lipoprotein plasma fraction (Svedberg flotation rate (Sf>400), in partially hydrolysed remnants (Sf 20-400) and in a TAG-deplete fraction (Sf<20), following ingestion of isoenergetic meals with either palm oil (PO), rice bran or coconut oil. Results from this study show that the majority of fasting chylomicrons are within the potentially pro-atherogenic Sf<20 fraction (70-75 %). Following the ingestion of test meals, chylomicronaemia was also principally distributed within the Sf<20 fraction. However, approximately 40 % of subjects demonstrated exaggerated postprandial lipaemia specifically in response to the SFA-rich PO meal, with a transient shift to more buoyant chylomicron fractions. The latter demonstrates that heterogeneity in the magnitude and duration of hyper-remnantaemia is dependent on both the nature of the meal fatty acids ingested and possible metabolic determinants that influence chylomicron metabolism. The study findings reiterate that fasting plasma TAG is a poor indicator of atherogenic chylomicron remnant homoeostasis and emphasises the merits of considering specifically, chylomicron remnant abundance and kinetics in the context of atherogenic risk. Few studies address the latter, despite the majority of life being spent in the postprandial and absorptive state.

Enzyme-Linked Immunoassay-Based Quantitative Measurement of Apolipoprotein B (ApoB) in Dried Blood Spots, a Biomarker of Cardiovascular Disease Risk

Apolipoprotein B (ApoB) is a strong predictor of cardiovascular disease, which remains the leading cause of mortality in both higher and lower income countries. Here, we adapted an enzyme-linked immunosorbent assay (ELISA) development kit for quantitative determination of ApoB levels in serum and plasma for use with dried blood spots (DBS). After confirming the dilution linearity of the assay for DBS, we measured ApoB in 208 venous DBS samples. Then, using Passing-Bablok regression analysis and Spearman rank correlation analysis, we evaluated the correspondence in ApoB values between matched plasma and finger-prick DBS samples from 40 individuals who had ApoB values spanning the range of ApoB values observed in the 208 vDBS samples. We also evaluated assay precision and recovery, the effects of hematocrit, number of freeze-thaw cycles, and different storage temperatures on ApoB levels in DBS. There was a strong, significant correlation between plasma and DBS ApoB levels with little bias. Assay precision and recovery were within the range recommended by the U.S. government's industry guidelines for bioanalytical assay validation. The assay was not affected by the DBS matrix or physiological hematocrit levels. This DBS-based ELISA assay will facilitate population-scale assessment of cardiovascular risk in previously unexplored populations.

Plasma triglyceride and high density lipoprotein cholesterol are poor surrogate markers of pro-atherogenic chylomicron remnant homeostasis in subjects with the metabolic syndrome

BACKGROUND

Subjects with metabolic syndrome (MetS) exhibit impaired lipoprotein metabolism and have an increased risk of cardiovascular disease. Although the risk is attributed primarily to the risk associated with individual components, it is also likely affected by other associated metabolic defects. Remnants of postprandial lipoproteins show potent atherogenicity in cell and animal models of insulin resistance and in pre-diabetic subjects with postprandial dyslipidemia. However, few studies have considered regulation of chylomicron remnant homeostasis in MetS per se. This study measured the plasma concentration in Caucasian men and women of small dense chylomicrons following fasting and explored associations with metabolic and anthropometric measures.

METHODS

A total of 215 Australian Caucasian participants (median age 62 years) were investigated. Of them, 40 participants were classified as having MetS. Apolipoprotein (apo) B-48, an exclusive marker of chylomicrons, metabolic markers and anthropometric measures were determined following an overnight fast.

RESULTS

The fasting apo B-48 concentration was 40 % higher in subjects with MetS than those without MetS. In all subjects, triglyceride (r = 0.445, P < 0.0005), non-HDL cholesterol (r = 0.28, P < 0.0005) and HDL cholesterol concentration (r = -0.272, P < 0.0005) were weakly associated with apo B-48 concentration. In subjects with MetS, the association of apo B-48 with triglyceride and non-HDL cholesterol was enhanced, but neither were robust markers of elevated apo B-48 in MetS (r = 0.618 and r = 0.595 respectively). There was no association between apo B-48 and HDL cholesterol in subjects with MetS.

CONCLUSION

This study demonstrates a substantial accumulation of pro-atherogenic remnants in subjects with MetS. We have shown that in a Caucasian cohort, the fasting plasma concentration of triglyceride or HDL/non-HDL cholesterol serves as poor surrogate markers of atherogenic chylomicron remnants. These findings suggest that subjects with MetS exhibit a chronic defect in chylomicron metabolism that is likely to contribute to their increased CV risk.