👤 Yosuke Tanigawa

Recently, we reported that a pemafibrate extended-release (XR) formulation lowered low-density lipoprotein cholesterol (LDL-C) and cholesterol synthesis and absorption markers in a phase 2 clinical pharmacology study. Here we describe our post-hoc analysis of that study, discuss the mechanism by which pemafibrate lowers LDL-C, and suggest which patients may respond favorably to pemafibrate treatment. In the phase 2 study, patients with hypertriglyceridemia received treatment with pemafibrate immediate-release (IR) 0.2 mg/day or XR 0.4 mg/day or 0.8 mg/day. This post-hoc subgroup analysis examined the percentage change in LDL-C, apolipoprotein B (ApoB), non-HDL-C, and cholesterol synthesis and absorption markers, in subgroups by baseline LDL-C, and then determined the correlation between the percentage change in LDL-C and the percentage change in cholesterol synthesis and absorption markers. Our analysis included 60 patients who received two of three formulations of the drug. A total of 78.3% (47/60) were male, 16.7% (10/60) had type 2 diabetes mellitus, and 10% (6/60) received concomitant statins. The percentage of LDL-C lowering was greater in the population with high baseline LDL-C, and similar trends were noted for the ApoB, non-HDL-C, and cholesterol synthesis and absorption markers. The percentage change in LDL-C was positively correlated with the percentage change in lathosterol, β-sitosterol, and campesterol. In patients with hypertriglyceridemia, results suggested that pemafibrate lowered LDL-C by inhibiting cholesterol synthesis in the liver and cholesterol absorption from the intestinal tract. This lowering effect was greater in populations with higher baseline LDL-C. Show less

In the PEMA-FL study in patients with metabolic dysfunction-associated steatotic liver disease (MASLD), pemafibrate was shown to significantly decrease low-density lipoprotein cholesterol (LDL-C) levels. We aimed to investigate the mechanisms of pemafibrate-induced LDL-C reduction in patients with MASLD by conducting an additional sub-analysis of the PEMA-FL study. The PEMA-FL study randomized 118 patients with MASLD to receive pemafibrate or placebo for 72 weeks. This sub-analysis examined the percentage change in LDL-C and related lipid markers by tertile of baseline LDL-C levels and the correlation between these changes in the pemafibrate group. Pemafibrate significantly decreased LDL-C levels approximately 25% (p＜0.001 at all timepoints) from baseline in the highest tertile of baseline LDL-C levels (≥ 137.5 mg/dL), with similar trends for non-high-density lipoprotein cholesterol (non-HDL-C) and apolipoprotein B (ApoB) levels. Lipoprotein (a) [Lp(a)] levels decreased only in patients with the highest baseline LDL-C levels. Regardless of the baseline LDL-C levels, pemafibrate altered the LDL particle profile (increased LDL particle size and decreased the number); reduced lathosterol, β-sitosterol, and campesterol; and increased angiopoietin-like protein 3 (ANGPTL3). The percentage change in LDL-C positively correlated with that in ApoB, non-HDL-C, Lp(a), lathosterol, β-sitosterol, and campesterol but not HDL-C and ANGPTL3. Pemafibrate reduced LDL-C, ApoB, and non-HDL-C levels in patients with MASLD, and the effect was greater in those with higher baseline LDL-C levels. Pemafibrate may clinically benefit patients with MASLD by improving LDL-C levels and the LDL particle profile. Show less

Cholesteryl ester transfer protein (CETP) deficiency is a representative molecular abnormality in familial hyperalphalipoproteinemia, a hereditary disorder of lipid metabolism characterized by markedly elevated plasma high-density lipoprotein cholesterol (HDL-C) levels. In this condition, dysfunction of CETP, which mediates the transfer of cholesteryl esters from HDL particles to apolipoprotein (Apo)B-containing lipoproteins, leads to the abnormal accumulation of HDL-C. These HDL particles are unusually large and enriched in cholesteryl esters, ApoCIII, and ApoE, whereas low-density lipoprotein (LDL) particles are small, depleted of cholesteryl esters, and enriched in triglycerides. Both HDL and LDL particles in CETP deficiency are functionally abnormal. Pemafibrate, a selective peroxisome proliferator-activated receptor α modulator, has consistently been demonstrated in clinical trials to increase HDL-C levels by 16% to 22% in patients with dyslipidemia and low baseline HDL-C. Herein, we describe the unexpected finding of a marked reduction in HDL-C levels in a patient with CETP deficiency following pemafibrate treatment. To better understand this paradoxical response, we analyzed the patient's clinical data and investigated potential mechanisms underlying pemafibrate's effects on HDL metabolism. Show less

Balancing the tradeoff between quantity and quality of phenotypic data is critical in omics studies. Measurements below the limit of quantification (BLQ) are often tagged in quality control fields, but these flags are currently underutilized in human genetics studies. Extreme phenotype sampling is advantageous for mapping rare variant effects. We hypothesize that genetic drivers, along with environmental and technical factors, contribute to the presence of BLQ flags. Here, we introduce "hypometric genetics" (hMG) analysis and uncover a genetic basis for BLQ flags, indicating an additional source of genetic signal for genetic discovery, especially from phenotypic extremes. Applying our hMG approach to n = 227,469 UK Biobank individuals with metabolomic profiles, we reveal more than 5% heritability for BLQ flags and report biologically relevant associations, for example, at APOC3, APOA5, and PDE3B loci. For common variants, polygenic scores trained only for BLQ flags predict the corresponding quantitative traits with 91% accuracy, validating the genetic basis. For rare coding variant associations, we find an asymmetric 65.4% higher enrichment of metabolite-lowering associations for BLQ flags, highlighting the impact of putative loss-of-function variants with large effects on phenotypic extremes. Joint analysis of binarized BLQ flags and the corresponding quantitative metabolite measurements improves power in Bayesian rare variant aggregation tests, resulting in an average of 181% more prioritized genes. Our approach is broadly applicable to omics profiling. Overall, our results underscore the benefit of integrating quality control flags and quantitative measurements and highlight the advantage of joint analysis of population-based samples and phenotypic extremes in human genetics studies. Show less

Hypertriglyceridemia has emerged as a critical coronary artery disease (CAD) risk factor. Rare loss-of-function (LoF) variants in apolipoprotein C-III have been reported to reduce triglycerides (TG) and are cardioprotective in American Indians and Europeans. However, there is a lack of data in other Europeans and non-Europeans. Also, whether genetically increased plasma TG due to ApoC-III is causally associated with increased CAD risk is still unclear and inconsistent. The objectives of this study were to verify the cardioprotective role of earlier reported six LoF variants of APOC3 in South Asians and other multi-ethnic cohorts and to evaluate the causal association of TG raising common variants for increasing CAD risk. We performed gene-centric and Mendelian randomization analyses and evaluated the role of genetic variation encompassing APOC3 for affecting circulating TG and the risk for developing CAD. One rare LoF variant (rs138326449) with a 37% reduction in TG was associated with lowered risk for CAD in Europeans (p = 0.007), but we could not confirm this association in Asian Indians (p = 0.641). Our data could not validate the cardioprotective role of other five LoF variants analysed. A common variant rs5128 in the APOC3 was strongly associated with elevated TG levels showing a p-value 2.8 × 10 Our results highlight the challenges of inclusion of rare variant information in clinical risk assessment and the generalizability of implementation of ApoC-III inhibition for treating atherosclerotic disease. More studies would be needed to confirm whether genetically raised TG and ApoC-III concentrations would increase CAD risk. Show less