PPAR-δ (EC50 = 2 μM); PPAR-α (EC50 = 1600 μM)
Seladelpar selectively targets the peroxisome proliferator-activated receptor-delta (PPAR-δ). It exhibits an EC50 of 2 nM for human PPAR-δ. It shows over 750-fold selectivity over PPAR-α and over 2500-fold selectivity over PPAR-γ. By activating PPAR-δ, it reduces bile acid synthesis via FGF21-mediated downregulation of CYP7A1, the rate-limiting enzyme in bile acid production.

Seladelpar (MBX-8025) is a PPAR-δ agonist that is being developed as a lipid-altering agent. It is orally active, potent (2 nM), and specific (>750-fold and >2500-fold compared with PPAR-α or PPAR-γ receptors, respectively)[1]. With a 50% effect concentration of human PPAR-δ = 2 nM and PPAR-α = 1,600 nM, seladelpar is a potent and selective PPAR-δ agonist that shows positive effects on atherogenic dyslipidemia, insulin resistance, and diabetes[2].

Following weaning, wild-type littermates and female Alms1 mutant (foz/foz) mice are given an atherogenic diet for 16 weeks.After that, groups (n=8–12) are randomized to receive either vehicle (1% methylcellulose) or Seladelpar (10 mg/kg) by gavage for an additional 8 weeks. Seladelpar normalizes glucose disposal, hyperglycemia, and hyperinsulinemia in foz/foz mice while hardly changing body weight. In mice treated with a vehicle, the serum level of alanine aminotransferase ranges from 300 to 600 U/L; Seladelpar reduces this level by 50%. Furthermore, Seladelpar restores normalcy to serum lipid levels, hepatic levels of free cholesterol, and other lipotoxic lipids that exhibit elevation in vehicle-treated foz/foz mice relative to wild-type mice. This significantly reduced steatosis and liver inflammation, eliminated hepatocyte ballooning and apoptosis, and improved liver fibrosis. The mean nonalcoholic fatty liver disease activity score in vehicle-treated foz/foz mice is 6.9, indicating nonalcoholic steatohepatitis (NASH); in all foz/foz mice, selegilegpar reverses NASH (nonalcoholic fatty liver disease activity score 3.13). When administered to Wt mice fed an atherogenic diet, Seladelpar reduces body weight by approximately 18% (P<0.05). On the other hand, Seladelpar has little effect on body weight in mice fed an atherogenic diet (foz/foz). After sixteen weeks (P<0.05), these animals develop severe hyperglycemia, hyperinsulinemia, and whole-body insulin resistance; selegilapar remarkably improves these indices (P<0.05). Following intraperitoneal injection of glucose, blood glucose levels in vehicle-treated mice reach approximately 32 mM, while in Seladelpar-treated foz/foz mice they reach approximately 14 mM (P<0.05); Seladelpar-treated foz/foz mice also have a lower area under the blood glucose disappearance curve (P<0.05). Seladelpar has a comparable effect (P<0.05) on glucose handling in Wt mice fed an atherogenic diet[2].

In vitro receptor binding and functional assays for Seladelpar involve measuring its activity at PPAR-δ. For binding affinity, radioligand binding studies using membranes from cells expressing human PPAR-δ are performed. Functional activity is assessed in cell-based reporter assays where the compound's ability to activate PPAR-δ-mediated transcription is measured. The compound's selectivity over PPAR-α and PPAR-γ is confirmed in similar assays using cells expressing these receptors.

In vitro cellular assays for Seladelpar are performed using cell lines to assess its effects on metabolic pathways. Hepatocytes or other relevant cells are treated with the compound, and the expression of PPAR-δ target genes involved in lipid metabolism and inflammation is measured by qPCR. The compound's ability to reduce lipid accumulation in cells can be assessed by Oil Red O staining or by measuring triglyceride content.

Mice: Atherogenic diet (23 percent fat, 0.2 percent cholesterol, and 45 percent simple carbohydrate; 4.78 kcal/g digestible energy) is fed ad libitum to Alms1 mutant (foz/foz) NOD.B10 mice or Wt littermates (female mice in both groups) from the time of weaning (week 4). Following this, groups are randomized (n=8–12 mice/group) to once-daily oral administration (by gavage) of Seladelpar (10 mg/kg in 1% methylcellulose) or vehicle (controls) for 8 weeks. Animals are kept in housing with a 12-hour light/dark cycle, a constant temperature of 22°C, and the highest level of humane treatment[2].
In vivo animal studies for Seladelpar have been conducted in female Alms1 mutant (foz/foz) mice, a model of NASH. These mice were fed a high-fat diet for 16 weeks and then treated with Seladelpar (10 mg/kg) or vehicle by oral gavage for 8 weeks. Endpoints included measurements of body weight, blood glucose, insulin, serum ALT, serum lipids, hepatic lipid levels, and histological assessment of liver steatosis, inflammation, and fibrosis.

Absorption
After a single dose, systemic exposure to celardpa increases proportionally with increasing dose, from 2 mg (0.2 times the recommended dose) to 15 mg (1.5 times the recommended dose), and then increases dose-proportionally with higher doses. When the dose increases from 10 mg to 200 mg (20 times the recommended dose), the mean Cmax and mean AUC of celardpa increase by 70-fold and 27-fold, respectively. After once-daily administration, celardpa reaches steady state on day 4, with an AUC increase of less than 30%. In patients with primary biliary cholangitis (PBC), after reaching steady state with once-daily administration of 10 mg celardpa, the mean (standard deviation) Cmax and AUC are 103 (29.3) ng/mL and 902 (238) ng·h/mL, respectively. The median time to peak concentration (Tmax) of celardpa is 1.5 hours. No clinically significant differences in the pharmacokinetics of seladelpar were observed in healthy subjects after ingestion of a high-fat meal.
Excretion Route
Seladelpar is primarily excreted in the urine as a metabolite. Following a single oral dose of 10 mg of radiolabeled seladelpar in humans, approximately 73.4% of the dose is excreted in the urine (less than 0.01% unchanged drug) and 19.5% is excreted in the feces (2.02% unchanged drug). Animal studies suggest that seladelpar may be excreted in the bile.
Volume of Distribution
The steady-state apparent volume of distribution of seladelpar is approximately 133.2 L.
Clearance
The apparent oral clearance of seladelpar is 12 L/h.
Protein Binding
The plasma protein binding of seladelpar is greater than 99%.
Metabolism/Metabolites
Seladelpar is primarily metabolized in vitro via CYP2C9, with minor metabolism via CYP2C8 and CYP3A4, yielding three major metabolites: seladelpar sulfoxide (M1), desethylseladelpar (M2), and desethylseladelpar sulfoxide (M3). The AUC ratios of the metabolites to the parent drug for M1, M2, and M3 are 0.36, 2.32, and 0.63, respectively. The median Tmax for the metabolites are 10 hours for M1, and 4 hours for both M2 and M3. All major metabolites are pharmacologically inactive.
Biological Half-Life
In healthy subjects, the mean elimination half-life of seladelpar is 6 hours after a single 10 mg dose. In patients with PBC, the half-life of seladelpar ranges from 3.8 to 6.7 hours.
Seladelpar is an orally active compound with good bioavailability. Its PK properties have been characterized in preclinical species and humans. As a PPAR-δ agonist, it is designed for oral administration and systemic exposure. Detailed PK parameters such as half-life, Cmax, and AUC are available from clinical trial data but are not detailed in the provided search results.

Hepatotoxicity
In pre-registration clinical trials, seladelpar was found to significantly reduce serum transaminase and alkaline phosphatase levels in most patients with primary biliary cholangitis (PBC). However, in an initial dose-exploration study of PBC patients, 3 out of 25 subjects (taking 50 mg and 200 mg daily) experienced transient increases in ALT and AST levels exceeding the upper limit of normal (ULN) by more than 5 times, while this did not occur in the placebo group. These increases occurred over several months of treatment and returned rapidly upon discontinuation of the drug. Notably, alkaline phosphatase levels decreased significantly during the ALT elevation and returned to pre-treatment levels quickly after discontinuation of the drug. In contrast, in subsequent clinical trials of seladelpar at a daily dose of 10 mg in PBC patients, ALT elevations exceeding 5 times the ULN were rare, occurred randomly, and were generally attributed to other causes. In a large, pre-registered, randomized, placebo-controlled trial, 2 out of 128 patients (1.6%) receiving seladelpar discontinued treatment due to abnormal liver function, compared to 2 out of 65 patients (3.1%) receiving placebo. No clinically significant liver injury caused by seladelpar has been reported in several small clinical trials. However, clinical experience with seladelpar is generally limited, and rare drug-induced liver injury is known to occur with other PPAR agonists such as fenofibrate, bezafibrate, pioglitazone, and rosiglitazone. In long-term extended studies, a small number of patients taking seladelpar experienced decompensation and jaundice, but all of these cases occurred in patients with pre-existing cirrhosis and were explained as being due to disease progression and unrelated to treatment. However, seladelpar and other PPAR agonists are not recommended for patients with advanced or decompensated cirrhosis, and regular monitoring of liver function is advised during treatment. Probability score: E (Unproven but suspected rare cause of clinically significant liver injury).
Comprehensive toxicological data for Seladelpar have been generated as part of its clinical development program. Standard preclinical safety assessments, including genotoxicity, safety pharmacology, and repeat-dose toxicity studies in rodents and non-rodents, would have been conducted. In animal models, it has shown a favorable safety profile, but specific toxicological data are not detailed in the provided sources.

[1]. MBX-8025, a novel peroxisome proliferator receptor-delta agonist: lipid and other metabolic effects in dyslipidemic overweight patients treated with and without atorvastatin. J Clin Endocrinol Metab. 2011 Sep;96(9):2889-97.

[2]. The selective peroxisome proliferator-activated receptor-delta agonist seladelpar reverses nonalcoholic steatohepatitis pathology by abrogating lipotoxicity in diabetic obese mice. Hepatol Commun. 2017 Jul 31;1(7):663-674.

Seladelpar (MBX-8025) has been used in clinical trials for the treatment of hyperlipidemia.

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Drug Indications
Treatment of primary biliary cholangitis
Mechanism of Action
Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear hormone receptor superfamily, which includes three members: PPAR-α, PPAR-δ, and PPAR-γ. Each PPAR plays a role in maintaining energy homeostasis and metabolic functions, such as fatty acid metabolism, bile acid synthesis, and adipocyte differentiation. In chronic liver diseases such as primary biliary cholangitis (PBC) and non-alcoholic steatohepatitis (NASH), altered bile acid composition and elevated systemic bile acid levels are observed. Seladelpar is a PPAR-δ agonist; however, the mechanism by which Seladelpar exerts its therapeutic effect in patients with PBC is not fully understood. Potential pharmacological activities related to therapeutic efficacy include inhibition of bile acid synthesis through activation of PPARδ. Published studies have shown that celadepa activation of PPARδ can reduce bile acid synthesis by inducing fibroblast growth factor 21 (FGF21), thereby activating the c-Jun N-terminal kinase (JNK) signaling pathway. This effect subsequently downregulates CYP7A1, a key enzyme in cholesterol-to-bile acid synthesis. Studies have shown that celadepa's inhibitory effect on bile acid synthesis is independent of the farnesoid X receptor (FXR) pathway, another molecular pathway regulating hepatic bile acid synthesis.
Pharmacodynamics
Celadepa can reduce total bile acid levels and decrease bile acid synthesis in patients with primary biliary cholangitis (PBC). Studies have shown that elevated bile acid concentrations in hepatobiliary diseases, including primary biliary cholangitis (PBC), can lead to elevated alkaline phosphatase (ALP) levels. In PBC patients treated with 10 mg seladelpar once daily, a significant reduction in mean ALP levels from baseline was observed one month after treatment compared to the placebo group, and the lower ALP levels typically persisted until month 12. In another study, a dose-dependent reduction in mean ALP levels was also observed in PBC patients treated with 2 mg, 5 mg, or 10 mg seladelpar once daily. Seladelpar is a peroxisome proliferator-activated receptor (PPAR)-δ agonist. Seladelpar is a single enantiomer of the R configuration. On August 14, 2024, the FDA granted accelerated approval to seladelpar for the treatment of primary biliary cholangitis, a disease associated with abnormal bile acid metabolism. Seladelpar works by blocking bile acid synthesis.
Serradepa is an oral peroxisome proliferator-activated receptor delta (PPARδ) agonist used in combination with ursodeoxycholic acid to treat primary biliary cholangitis (PBC). Rarely, elevated liver enzymes have been observed during serradepa treatment, but there is no conclusive evidence linking them to clinically significant liver damage with jaundice.
Serradepa is an orally bioavailable peroxisome proliferator-activated receptor (PPAR)-δ (PPARd) agonist whose activity is reduced by bile acids. After oral administration, serradepa targets, binds to, and activates PPARd in the liver. This induces the expression of fibroblast growth factor 21 (FGF21), which downregulates the activity of CYP7A1, a key enzyme in the synthesis of bile acids from cholesterol. By reducing CYP7A1 expression, bile acid synthesis is reduced. This may alleviate inflammation and scarring associated with primary biliary cholangitis (PBC). SELADELPAR is a small molecule drug that has completed Phase IV clinical trials (covering all indications) and was first approved in 2024 for the treatment of biliary cirrhosis. It also has 6 investigational indications.
Seladelpar is also known as MBX-8025 and RWJ800025. It is a potent and selective PPAR-δ agonist. It has been investigated in clinical trials for the treatment of dyslipidemia, NASH, and primary biliary cholangitis (PBC). Its development has been closely watched for its potential to treat metabolic and liver diseases.

C21H23F3O5S

444.464535951614

444.121

C, 56.75; H, 5.22; F, 12.82; O, 18.00; S, 7.21

851528-79-5

851528-79-5; 928821-40-3 (lysine hydrate); 3026272-26-1 (sodium); 928821-41-4 (lysine)

11236126

Colorless to light yellow liquid

1.3±0.1 g/cm3

557.5±50.0 °C at 760 mmHg

291.0±30.1 °C

0.0±1.6 mmHg at 25°C

1.554

6.16

1

9

11

30

511

1

O(C1C=CC(SC[C@H](OCC)COC2C=CC(C(F)(F)F)=CC=2)=CC=1C)CC(=O)O

JWHYSEDOYMYMNM-QGZVFWFLSA-N

InChI=1S/C21H23F3O5S/c1-3-27-17(11-28-16-6-4-15(5-7-16)21(22,23)24)13-30-18-8-9-19(14(2)10-18)29-12-20(25)26/h4-10,17H,3,11-13H2,1-2H3,(H,25,26)/t17-/m1/s1

2-[4-[(2R)-2-ethoxy-3-[4-(trifluoromethyl)phenoxy]propyl]sulfanyl-2-methylphenoxy]acetic acid

MBX-8025; RWJ800025; MBX 8025; Seladelpar; 851528-79-5; RWJ-800,025; (+)-MBX-8025; 7C00L34NB9; RWJ800025; MBX8025; RWJ-800025

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 (~225 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (5.62 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 (5.62 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.)