S1P1 ( IC50 = 1.88 nM )

Etrasimod arginine/APD-334 has a relatively low systemic clearance (<4% of hepatic blood flow) and high Cmax across all species. A notable reduction in volume of distribution (Vss) is noted in dogs and monkeys when compared to rodents. Oral bioavailability ranges from 40 to 100%, and the terminal phase half-life in dogs can reach up to 29 hours, while in monkeys it only lasts 6 hours. The t1/2 values for siponimod, an additional S1P1 modulator presently undergoing human trials, have been revealed to be 6 and 19 hours, respectively, for rats and monkeys[1].

Rats: Male Sprague-Dawley rats are used to assess the effects of APD334 on blood lymphopenia. Male rats are administered an oral dose of APD334 formulated in 0.5% methylcellulose (MC) in water at a rate of 0 mg/kg (vehicle only), 0.03 mg/kg (mice only), 0.1, 0.3, or 1 mg/kg. Samples of rat blood are taken 0, 1, 3, 5, 8, 16, 24, 32, 48, and 72 hours after the dose[1].
Mice: Male BALB/c mice are used to study the effects of APD334 on blood lymphopenia. In summary, APD334 is administered orally to male mice at doses of 0 (vehicle only), 0.03 (mice only), 0.1, 0.3, or 1 mg/kg when formulated in 0.5% methylcellulose (MC) in water. At 0, 1, 3, 5, 8, 16, 24, and 32 hours after administration, mouse blood samples are collected[1].

Absorption, Distribution and Excretion
Etrasimod mean (SD) steady-state maximum plasma concentration (Cmax) was 113 (27.5) ng/mL and the area under the time concentration curve at the dosing interval (AUCtau) was 2162 (488) ng*h/mL at the recommended dosage. Etrasimod Cmax and AUC are approximately dose-proportional from 0.7 mg to 2 mg (0.35 times up to the recommended dosage). Etrasimod steady state is reached within 7 days with an accumulation of approximately 2- to 3-fold compared to the first dose. The median (range) time to reach etrasimod Cmax (Tmax) is approximately 4 hours (range 2 to 8 hours) after oral administration. No clinically significant differences in the pharmacokinetics of etrasimod were observed following administration of etrasimod with a high-fat meal (800 to 1000 calories).
Approximately 82% of the total radioactive etrasimod dose was recovered in the feces and 5% in the urine within 336 hours. Approximately 11% of the administered radioactive dose was excreted as unchanged etrasimod in feces and none was excreted unchanged in urine.
The mean apparent volume of distribution of etrasimod is 66 (24) L.
The apparent steady-state oral clearance of etrasimod is approximately 1 L/h after oral administration.

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Metabolism / Metabolites
Etrasimod is metabolized by oxidation and dehydrogenation mediated primarily by CYP2C8, CYP2C9, and CYP3A4, with a minor contribution by CYP2C19 and CYP2J2. Etrasimod also undergoes conjugation primarily mediated by UGTs, with a minor contribution by sulfotransferases. Unchanged etrasimod is the main circulating component in plasma.

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Biological Half-Life
The mean plasma elimination half-life (t_1/2) of etrasimod is approximately 30 hours.

Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
No information is available on the use of etrasimod during breastfeeding. Because etrasimod is 98% bound to plasma proteins, the amount in milk is likely to be low. If the mother requires etrasimod, it is not a reason to discontinue breastfeeding. Until more data become available, etrasimod should be used with caution during breastfeeding, especially while nursing a newborn or preterm infant.
◉ Effects in Breastfed Infants
Relevant published information was not found as of the revision date.
◉ Effects on Lactation and Breastmilk
Relevant published information was not found as of the revision date.

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Protein Binding
Etrasimod plasma protein binding is 97.9%.

[1]. Discovery of APD334: Design of a Clinical Stage Functional Antagonist of the Sphingosine-1-phosphate-1 Receptor. ACS Med Chem Lett. 2014 Nov 4;5(12):1313-7.

Etrasimod is an organic heterotricyclic compound that is 1,2,3,4-tetrahydrocyclopenta[b]indole substituted by carboxymethyl and [4-cyclopentyl-3-(trifluoromethyl)phenyl]methoxy groups at positions 3R and 7, respectively. It is a potent and functional antagonist of the sphingosine-1-phosphate-1 (S1P1) receptor (IC50 = 1.88 nM in CHO cells). It has a role as an antibacterial agent, a sphingosine-1-phosphate receptor 1 antagonist, an immunosuppressive agent and an anti-inflammatory drug. It is a member of (trifluoromethyl)benzenes, a member of cyclopentanes, an aromatic ether, a monocarboxylic acid and an organic heterotricyclic compound. It is a conjugate acid of an etrasimod(1-).
Etrasimod is a synthetic next-generation selective Sphingosine 1-phosphate (S1P) receptor modulator that targets the S1P1,4,5 with no detectable activity on S1P2 and S1P3 receptors. S1P receptors are membrane-derived lysophospholipid signaling molecules that are involved in the sequestration of circulating peripheral lymphocytes in lymph nodes. Therefore, S1P receptor modulators like etrasimod were investigated in treating immune-mediated diseases like ulcerative colitis where a high level of inflammatory T cells is present in the gastrointestinal tract, thus causing diffuse mucosal inflammation. In fact, it has been observed that antigen-activated T cells within peripheral lymphoid organs can transiently downregulate S1P receptor levels to facilitate immune cells trafficking into the intestinal mucosa. Etrasimod was approved on October 13, 2023, by the FDA under the brand name VELSIPITY for the treatment of adults with moderately to severely active ulcerative colitis. This approval was based on favorable results obtained from Pfizer’s Elevate UC Phase III registrational program, consisting of the Elevate UC 52 and Elevate UC 12 clinical trials, that investigates the efficacy of a 2-mg daily dose regimen of etrasimod, with a 32% and 26% remission rate observed in UC 52 and UC 12 trials respectively.

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Drug Indication
Etrasimod is indicated for the treatment of moderately to severely active ulcerative colitis (UC) in adults.

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Mechanism of Action
Etrasimod is a sphingosine 1-phosphate (S1P) receptor modulator that binds with high affinity to S1P receptors 1, 4, and 5 (S1P_1,4,5). Etrasimod has minimal activity on S1P₃ (25-fold lower than C_max at the recommended dose) and no activity on S1P₂. Etrasimod partially and reversibly blocks the capacity of lymphocytes to egress from lymphoid organs, reducing the number of lymphocytes in peripheral blood. The mechanism by which etrasimod exerts therapeutic effects in UC is unknown but may involve the reduction of lymphocyte migration into the intestines.

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Pharmacodynamics
Etrasimod causes a reduction in peripheral blood lymphocyte count. In UC-1 and UC-2, mean lymphocyte counts decreased to approximately 50% of baseline at 2 weeks (approximate mean blood lymphocyte counts 0.9 x 109/L) and the lower lymphocyte counts were maintained during treatment with etrasimod. Dose-response relationship analysis indicates there is a dose-dependent reduction in blood lymphocyte counts. After discontinuing etrasimod 2 mg once daily, the median time for peripheral blood lymphocytes to return to the normal range was 2.6 weeks, with approximately 90% of subjects in the normal range within 4.7 weeks. Etrasimod may result in a transient decrease in heart rate and AV conduction upon treatment initiation. In UC-1 and UC-2, the mean (SD) decrease in heart rate was 7.2 (8.98) bpm at 2 to 3 hours after the first dose of etrasimod on Day 1. At 2 times the maximum recommended dose, etrasimod does not cause clinically significant QTc interval prolongation. Reductions in absolute FEV1 were also observed in subjects treated with etrasimod.

C26H26F3NO3

457.49321

457.186

C, 68.26; H, 5.73; F, 12.46; N, 3.06; O, 10.49

1206123-37-6

1206123-37-6; 1206123-97-8 (arginine)

44623998

White to khaki solid powder

1.3±0.1 g/cm3

621.4±50.0 °C at 760 mmHg

329.6±30.1 °C

0.0±1.9 mmHg at 25°C

1.606

6.43

2

6

6

33

695

1

FC(F)(F)C1=CC(COC2=CC=C(NC3=C4CC[C@@H]3CC(O)=O)C4=C2)=CC=C1C5CCCC5

MVGWUTBTXDYMND-QGZVFWFLSA-N

InChI=1S/C26H26F3NO3/c27-26(28,29)22-11-15(5-8-19(22)16-3-1-2-4-16)14-33-18-7-10-23-21(13-18)20-9-6-17(12-24(31)32)25(20)30-23/h5,7-8,10-11,13,16-17,30H,1-4,6,9,12,14H2,(H,31,32)/t17-/m1/s1

2-[(3R)-7-[[4-cyclopentyl-3-(trifluoromethyl)phenyl]methoxy]-1,2,3,4-tetrahydrocyclopenta[b]indol-3-yl]acetic acid

APD 334; APD334; APD-334; Etrasimod; Velsipity

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: ≥ 28 mg/mL (~61.2 mM)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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