PPARδ (EC50 = 1.06 μM); PPARγ (EC50 = 1.47 μM); PPARα (EC50 = 22.4 μM); COX-2 (IC50 = 48 μM)

With EC50 values of 22.4 µM, 1.47 µM, and 1.06 µM for PPARα, PPARγ, and PPARδ, respectively, fenofibric acid is a PPAR activator[1]. With an IC50 of 48 nM, fenofibric acid (10, 25, 50, 75, and 100 nM) dose-dependently inhibits the COX-2 enzyme [2]. In HepG2 cells, the quantity of AOX1 protein is decreased by 500 nM of fenofibric acid [3]. At a concentration of 100 µM, fenofibric acid inhibits the phosphorylation of JNK1/2, c-Jun, and p38 MAPK. Additionally, it prevents the buildup of reactive oxygen species, endoplasmic reticulum stress, and disruption of the blood-retina barrier (BRB). ARPE-19 cells exhibit hypoxia and high glucose (HG). In ARPE-19 cells exposed to hypoxia and HG conditions, fenofibric acid (100 µM) triggers the IGF-IR/Akt/ERK1/2-mediated survival signaling pathway [4].

Fenofibric Acid (1, 5, 10 mg/kg, oral) shows anti-inflammatory action against carrageenan-induced acute inflammation in Wistar rats [2].

Adiponectin protects the liver from steatosis caused by obesity or alcohol and therefore the influence of adiponectin on human hepatocytes was analyzed. GeneChip experiments indicated that recombinant adiponectin downregulates aldehyde oxidase 1 (AOX1) expression and this was confirmed by real-time RT-PCR and immunoblot. AOX1 is a xenobiotic metabolizing protein and produces reactive oxygen species (ROS), that promote cell damage and fibrogenesis. Adiponectin and fenofibric acid activate peroxisome proliferator-activated receptor-alpha (PPAR-alpha) and both suppress AOX1 protein and this is blocked by the PPAR-alpha antagonist RU486. Obesity is associated with low adiponectin, reduced hepatic PPAR-alpha activity and fatty liver, and AOX1 was found induced in the liver of rats on a high-fat diet when compared to controls. Free fatty acids and leptin, that are elevated in obesity, failed to upregulate AOX1 in vitro. The current data indicate that adiponectin reduces AOX1 by activating PPAR-alpha whereas fatty liver disease is associated with elevated hepatic AOX1. High AOX1 may be associated with higher ROS well described to induce fibrogenesis in liver tissue but may also influence drug metabolism and activity[3].

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Fenofibrate, an anti-hyperlipidemic drug and its phase-I biotransformed metabolite fenofibric acid, was studied for COX-1 (PDB ID: 3N8Y) and COX-2 (PDB ID: 1PXX) inhibition potentials in silico and in vitro for their effects on human recombinant COX-2 enzyme isolated from a Baculovirus expression system in sf21 cells (EC 1.14.99.1) using a conventional spectrophotometric assay. The test compounds fenofibric acid, fenofibrate, and the standard drug diclofenac exhibited binding energies of - 9.0, - 7.2, and - 8.0 kcal mol-1, respectively, against COX-2 and - 7.2, - 7.0, and - 6.5 kcal mol-1, respectively, against COX-1. In in vitro studies, both the test compounds inhibited COX-2 enzyme activity. Fenofibric acid showed an IC50 value of 48 nM followed by fenofibrate (82 nM), while diclofenac showed an IC50 value of 58 nM[2].

In this study, we found an imbalance between stress-mediated and survival signaling and elevated apoptotic markers in retinal pigment epithelium (RPE) from diabetic patients. Since fenofibric acid (FA) treatment reduces the progression of diabetic retinopathy (DR), we investigated the effect of hyperglycemia and hypoxia, two components of the diabetic milieu, on stress, apoptosis, and survival pathways in ARPE-19 cells (immortalized human RPE cell line) and whether FA is able to prevent the deleterious effects induced by these conditions. ARPE-19 cells cultured in high-glucose (HG) medium or under hypoxia (1% oxygen)-induced phosphorylation of the stress-activated kinases JNK and p38 MAPK. This effect was increased by the combination of both conditions. Likewise, hyperglycemia and hypoxia triggered the phosphorylation of the endoplasmic reticulum (ER) stress markers PERK and eIF2α and the induction of the pro-apoptotic transcription factor CHOP. Under these experimental conditions, reactive oxygen species (ROS) were elevated and the integrity of tight junctions was disrupted. Conversely, ARPE-19 cells treated with FA were protected against these deleterious effects induced by hyperglycemia and hypoxia. FA increased insulin-like growth factor I receptor (IGF-IR)-mediated survival signaling in cells cultured under hyperglycemia and hypoxia, thereby suppressing caspase-3 activation and down-regulation of BclxL. Moreover, FA increased LC3-II, an autophagy marker. In conclusion, our results demonstrated that FA elicits a dual protective effect in RPE by down-regulation of stress-mediated signaling and induction of autophagy and survival pathways. These molecular mechanisms could be involved in the beneficial effects of fenofibrate reported in clinical trials[4].

Fenofibrate was screened for their anti-inflammatory potentials in vivo using carrageenan-induced paw oedema method in Wistar rats. Furthermore, under in vivo conditions in carrageenan-induced paw oedema rodent model, fenofibric acid exhibited relatively potent anti-inflammatory activity compared with fenofibrate. Hence, we conclude that fenofibric acid and fenofibrate are not only anti-hyperlipidemic but also shows potent anti-inflammatory activity, which may have an additional impact in the treatment of diabetic complications, viz., hyperlipidemia and inflammation leading to atherosclerosis[2].

Absorption, Distribution and Excretion
Some studies have demonstrated that the bioavailability of fenofibric acid (a sample administration of 130 mg oral suspension to healthy volunteers about 4 hours after a light breakfast) is approximately 81% in the stomach, 88% in the proximal small bowel, 84% in the distal small bowel, and 78% in the colon. Nevertheless, following the oral administration of fenofibric acid in healthy volunteers, median peak plasma levels for the drug occurred about 2.5 hours after administration. Moreover, exposure after administration of three 35 mg fenofibric acid tablets is largely comparable to that of one 105 mg tablet.
Fenofibric acid metabolites are largely excreted in the urine.
The volume of distribution for fenofibric acid is demonstrated to be 70.9 +/- 27.5 L.
In five elderly volunteers aged 77 to 87, the oral clearance of fenofibric acid after a single oral dose of fenofibrate was 1.2 L/h, which compares to 1.1 L/h in young adults.

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Metabolism / Metabolites
In vitro and in vivo metabolism studies reveal that fenofibric acid does not experience significant oxidative metabolism via the cytochrome P450 isoenzymes. The CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, and CYP3A4 enzymes are not known to play a role in the metabolism of fenofibric acid. Rather, fenofibric acid is predominantly conjugated with glucuronic acid and then excreted in urine. A small amount of fenofibric acid is reduced at the carbonyl moiety to benzhydrol metabolite which is, in turn, conjugated with glucuronic acid and excreted in urine.
Fenofibric Acid has known human metabolites that include Fenofibryl glucuronide.

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Biological Half-Life
Following once daily dosing, fenofibric acid demonstrates an elimination associated with a half-life of about 20 hours after absorption.

Protein Binding
Fenofibric acid demonstrates serum protein binding of approximately 99% in ordinary and hyperlipidemic subjects.

[1]. Comparative molecular profiling of the PPARα/γ activator aleglitazar: PPAR selectivity, activity and interaction with cofactors. ChemMedChem. 2012 Jun;7(6):1101-11.

[2]. Anti-inflammatory activity of anti-hyperlipidemic drug, fenofibrate, and its phase-I metabolite fenofibric acid: in silico, in vitro, and in vivo studies. Inflammopharmacology. 2017 Dec 13.

[3]. Aldehyde oxidase 1 is highly abundant in hepatic steatosis and is downregulated by adiponectin and fenofibric acid in hepatocytes in vitro. Biochem Biophys Res Commun. 2006 Nov 24;350(3):731-5. Epub 2006 Sep 27.

[4]. Beneficial effects of fenofibrate in retinal pigment epithelium by the modulation of stress and survival signaling under diabetic conditions. J Cell Physiol. 2012 Jun;227(6):2352-62.

Fenofibric acid is a monocarboxylic acid that is 2-methylpropanoic acid substituted by a 4-(4-chlorobenzoyl)phenoxy group at position 2. It is a metabolite of the drug fenofibrate. It has a role as a marine xenobiotic metabolite and a drug metabolite. It is a chlorobenzophenone, a monocarboxylic acid and an aromatic ketone.
Fenofibric acid is a lipid-lowering agent that is used in severe hypertriglyceridemia, primary hyperlipidemia, and mixed dyslipidemia. It works to decrease elevated low-density lipoprotein cholesterol, total cholesterol, triglycerides, apolipoprotein B, while increasing high-density lipoprotein cholesterol. Due to its high hydrophilicity and poor absorption profile, prodrug ,[fenofibrate], and other conjugated compounds of fenofibric acid, such as choline fenofibrate, have been developed for improved solubility, gastrointestinal absorption, and bioavailability, and more convenient administration.
Fenofibric acid is a Peroxisome Proliferator Receptor alpha Agonist.
Fenofibric Acid is the active form of fenofibrate, a synthetic phenoxy-isobutyric acid derivate with antihyperlipidemic activity.
See also: Fenofibrate (active moiety of); Choline Fenofibrate (active moiety of).

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Drug Indication
For use as an adjunctive therapy to diet to: (a) reduce triglyceride levels in adult patients with severe hypertriglyceridemia, and (b) reduce elevated total cholesterol, low-density-lipoprotein (LDL-C), triglycerides, and apolipoprotein B, and to increase high-density-lipoprotein (HDL-C) in adult patients with primary hypercholesterolemia or mixed dyslipidemia (Fredrickson Types IIa and IIb).
FDA Label

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Mechanism of Action
Having performed clinical studies with in vivo transgenic mice and in vitro human hepatocyte cultures, it is believed that the principal mechanism of action of fenofibric acid is demonstrated through its capability to activate peroxisome proliferator receptor alpha (PPAR-alpha). By activating PPAR-alpha, fenofibric acid increases lipolysis and the elimination of triglyceride-rich particles from plasma by actuating lipoprotein lipase and reducing production of apoprotein C-III, which acts as an inhibitor of lipoprotein lipase activity. The resultant decrease in triglycerides causes an alteration in the size and composition of low-density-lipoprotein from small, dense particles to large, buoyant ones. The size of these larger low-density-lipoprotein particles have a greater affinity for cholesterol receptors and are therefore catabolized more rapidly. Additionally, fenofibric acid's activation of PPAR-alpha also induces an increase in the synthesis of apoproteins apo A-I, apo A-II, and high-density-lipoprotein. Moreover, the use of fenofibric acid can also act to reduce serum uric acid levels in ordinary or hyperuricemic individuals by increasing the urinary excretion of uric acid.

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Pharmacodynamics
Various clinical studies have shown that elevated levels of total cholesterol, low-desnsity-lipoprotein (LDL-C), and apolipoprotein B (apo B) - an LDL membrane complex - are associated with human atherosclerosis. Concurrently, decreased levels of high-density-lioprotein (HDL-C) and its transport complex, apolipoproteins apo AI and apo AII, are associated with the development of atherosclerosis. Furthermore, epidemiological investigations demonstrate that cardiovascular morbidity and mortality vary directly with the levels of total cholesterol, LDL-C, and triglycerides, and inversely with the level of HDL-C. Fenofibric acid, the active metabolite of fenofibrate, subsequently produces reductions in total cholesterol, LDL-C, apo B, total triglycerides, and triglyceride rich lipoprotein (VLDL) in treated patients. Moreover, such treatment with fenofibrate also results in increases in HDL-C and apo AI and apo AII.

C17H15O4CL

318.7516

318.065

C, 64.06; H, 4.74; Cl, 11.12; O, 20.08

42017-89-0

Choline Fenofibrate;856676-23-8;Fenofibric acid (Standard);42017-89-0;Fenofibric acid-d6;1092484-69-9

64929

White to off-white solid powder

1.3±0.1 g/cm3

486.5±35.0 °C at 760 mmHg

176--179ºC

248.0±25.9 °C

0.0±1.3 mmHg at 25°C

1.585

3.86

1

4

5

22

405

0

MQOBSOSZFYZQOK-UHFFFAOYSA-N

InChI=1S/C17H15ClO4/c1-17(2,16(20)21)22-14-9-5-12(6-10-14)15(19)11-3-7-13(18)8-4-11/h3-10H,1-2H3,(H,20,21)

2-[4-(4-chlorobenzoyl)phenoxy]-2-methylpropanoic acid

Procetofenic acid; 2-(4-(4-Chlorobenzoyl)phenoxy)-2-methylpropanoic acid; 2-[4-(4-chlorobenzoyl)phenoxy]-2-methylpropanoic acid; Trilipix; alpha 1081; LF 178 acid;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ≥ 100 mg/mL (~313.73 mM)
H2O : ~1 mg/mL (~3.14 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (7.84 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (7.84 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)