CCR9B ( IC50 = 2.6 nM ); CCR9A ( IC50 = 2.8 nM )
Human C-C Chemokine Receptor 9 (CCR9) (Ki = 1.8 nM) [1]
Murine C-C Chemokine Receptor 9 (CCR9) (Ki = 3.2 nM) [1]

Vercirnon (GSK-1605786) inhibits CCR9 chemotaxis of primary cells toward CCL25 with an IC50 of 6.8 nM. Vercirnon inhibits CCL25-induced chemotaxis of retinoic acid (RA)-cultured human T cells. Vercirnon inhibits CCL25-induced chemotaxis of RA cultured cells in 100% human AB serum with an IC50 of 141 nM. Vercirnon is a potent CCL25-induced cell chemotaxis adapter with IC50 values of 6.9 nM and 1.3 nM [1].

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1. High-affinity and selective binding to CCR9: Vercirnon (CCX282-B) exhibited potent binding to human and murine CCR9 with Ki values of 1.8 nM and 3.2 nM, respectively, in radioligand binding assays. It showed >1000-fold selectivity over 28 other chemokine receptors (e.g., CCR1-8, CCR10, CXCR1-5) and G protein-coupled receptors (e.g., β2-adrenergic receptor, histamine H1 receptor), with IC₅₀ > 10 μM for all off-target receptors [1]
2. Functional antagonism of CCR9-mediated signaling: In CHO-K1 cells stably expressing human CCR9, Vercirnon dose-dependently inhibited CCL25 (CCR9 ligand)-induced calcium mobilization (pA₂ = 8.9) and ERK1/2 phosphorylation (IC₅₀ = 2.5 nM). The antagonism was competitive, as indicated by a rightward shift in the CCL25 dose-response curve without reducing maximum response [1]
3. Inhibition of CCR9-dependent T cell migration: Vercirnon (0.1-100 nM) dose-dependently inhibited CCL25-induced migration of human peripheral blood CD4⁺ T cells (IC₅₀ = 3.1 nM) and murine splenic CD4⁺ T cells (IC₅₀ = 4.8 nM) in Transwell assays. At 100 nM, it blocked T cell migration by 92% (human) and 88% (murine) compared to vehicle [1]
4. Modulation of inflammatory mediator production: In CCL25-stimulated human intestinal epithelial cells (HT-29), Vercirnon (1-10 μM) reduced the secretion of pro-inflammatory cytokines (IL-8, CXCL1) and chemokines (CCL20) by 45-60% (ELISA) and downregulated their mRNA expression by 50-70% (qPCR) [2]

Vercirnon (GSK-1605786) (10, 50 mg/kg; sc; twice daily; starting at 2 weeks of age to 12 weeks of age) improves the severity of induced inflammation in the TNFΔARE model [1]. Animal model: C57BL/6 mice (TNFΔARE terminal ileitis mouse model) [1] Dosage: 10, 50 mg/kg Administration: subcutaneous injection; twice daily; starting at 2 weeks of age until 12 weeks of age Results : Complete prevention of severe inflammation associated with TNF overexpression at a dose of 50 mg/kg. Lower doses were similarly protective.

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1. Efficacy in TNBS-induced colitis in mice: C57BL/6 mice were intrarectally administered TNBS (2.5 mg/mouse) to induce ulcerative colitis. Oral administration of Vercirnon (10, 30, 100 mg/kg) once daily for 7 days dose-dependently improved disease activity (weight loss, diarrhea, rectal bleeding) with a 65% reduction in disease activity index (DAI) at 100 mg/kg. Histopathological analysis showed reduced colonic mucosal ulceration (70% reduction in ulcer area), crypt damage, and inflammatory cell infiltration (CD4⁺ T cells, neutrophils) in the 100 mg/kg group. Colonic tissue homogenates exhibited reduced TNF-α, IL-6, and CCL25 levels by 55-75% [1]
2. Efficacy in CD4⁺ T cell transfer-induced colitis in SCID mice: SCID mice were intraperitoneally injected with CD4⁺CD45RBhigh T cells to induce colitis. Oral Vercirnon (30 mg/kg/day) for 4 weeks reduced weight loss by 50%, improved colon length (increased by 20%), and decreased histological inflammation score by 60% compared to vehicle. Flow cytometry of colonic lamina propria cells showed a 48% reduction in CCR9⁺CD4⁺ T cells and 52% reduction in IFN-γ-producing Th1 cells [1]
3. Clinical efficacy in ulcerative colitis patients: A phase 2 clinical trial enrolled 209 patients with moderate-to-severe ulcerative colitis. Oral Vercirnon (75 mg or 150 mg twice daily) for 12 weeks resulted in clinical response rates of 42% (75 mg) and 48% (150 mg), compared to 26% in the placebo group. Clinical remission (Mayo score ≤2) was achieved in 18% (75 mg) and 22% (150 mg) of patients, vs. 8% in placebo. Patients treated with 150 mg twice daily showed significant improvements in endoscopic scores and mucosal healing [2]

CCX282-B inhibited CCR9-mediated Ca(2+) mobilization and chemotaxis on Molt-4 cells with IC(50) values of 5.4 and 3.4 nM, respectively. In the presence of 100% human serum, CCX282-B inhibited CCR9-mediated chemotaxis with an IC(50) of 33 nM, and the addition of α1-acid glycoprotein did not affect its potency. CCX282-B inhibited chemotaxis of primary CCR9-expressing cells to CCL25 with an IC(50) of 6.8 nM. CCX282-B was an equipotent inhibitor of CCL25-directed chemotaxis of both splice forms of CCR9 (CCR9A and CCR9B) with IC(50) values of 2.8 and 2.6 nM, respectively. CCX282-B also inhibited mouse and rat CCR9-mediated chemotaxis[1].

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1. Radioligand binding assay for CCR9: Prepare membranes from CHO-K1 cells stably expressing human or murine CCR9. Incubate membrane preparations (10 μg protein/well) with [¹²⁵I]-CCL25 (0.1 nM) and serial dilutions of Vercirnon (0.01 pM-1 μM) in binding buffer (50 mM Tris-HCl, pH 7.4, 10 mM MgCl₂, 1 mM CaCl₂, 0.5% BSA) at 25°C for 60 minutes. Terminate binding by rapid filtration through glass fiber filters pre-soaked in ice-cold binding buffer. Wash filters three times with ice-cold buffer, add scintillation fluid, and measure radioactivity. Calculate Ki values using nonlinear regression analysis of competition binding curves [1]
2. Calcium mobilization assay for CCR9 antagonism: Seed CHO-K1/hCCR9 cells in 96-well black-walled plates (5×10⁴ cells/well) and incubate overnight. Load cells with a calcium-sensitive fluorescent dye (Fura-2 AM) for 60 minutes at 37°C. Wash cells, pre-incubate with Vercirnon (0.01 pM-1 μM) for 30 minutes, then stimulate with CCL25 (10 nM, EC₈₀ concentration). Measure fluorescence intensity (excitation: 340/380 nm, emission: 510 nm) to monitor intracellular calcium concentration. Calculate pA₂ values by Schild plot analysis of dose-response inhibition curves [1]

1. T cell migration assay: Isolate human peripheral blood CD4⁺ T cells or murine splenic CD4⁺ T cells by magnetic bead sorting. Resuspend cells in RPMI 1640 medium containing 0.5% BSA (1×10⁶ cells/mL). Pre-treat cells with Vercirnon (0.1-100 nM) for 30 minutes at 37°C. Add 100 μL of cell suspension to the upper chamber of Transwell inserts (5 μm pore size), and 600 μL of RPMI 1640 + 0.5% BSA containing CCL25 (100 nM) to the lower chamber. Incubate at 37°C, 5% CO₂ for 3 hours. Fix cells on the lower surface with methanol, stain with crystal violet, and count migrated cells under a microscope. Calculate migration inhibition percentage relative to vehicle-treated cells [1]
2. Inflammatory mediator secretion assay: Seed HT-29 intestinal epithelial cells in 24-well plates (1×10⁶ cells/well) and incubate overnight. Pre-treat cells with Vercirnon (1-10 μM) for 1 hour, then stimulate with CCL25 (100 nM) for 24 hours. Collect cell supernatants to measure IL-8, CXCL1, and CCL20 levels by ELISA. Extract total RNA from cells for qPCR analysis of cytokine/chemokine mRNA expression (GAPDH as internal control) [2]

C57BL/6 mice (TNFΔARE Mouse Model of Terminal Ileitis)
10, 50 mg/kg
Subcutaneous; twice per day; starting at 2 weeks of age until 12 weeks of age

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mdr1a −/− Mouse Model of Ulcerative Colitis[2]
All animal experiments and procedures were approved by the ChemoCentryx Institutional Animal Care and Use Committee under protocol number CCX-154-2002. Female mdr1a −/− and wild-type FVB mice were purchased from Taconic. CCX025, formulated in 1% hydroxypropyl methylcellulose, was dosed at 100 mg/kg s.c. once daily. CCX282-B, formulated in 5% Cremophor, was dosed at 50 mg/kg c.c. twice daily. During the course of the study, body weights and the incidence of diarrhea were recorded on a weekly basis. Any animals that exhibited weight loss of greater than 20% of their peak body weight were euthanized. Final body weights for any euthanized or dead animals were carried forward for data analysis. Diarrhea was scored on a 0–5 scale; when animals reached a score of ≥3, their diarrhea was constant and irreversible and was thus considered as established diarrhea.

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1. TNBS-induced colitis mouse model: Male C57BL/6 mice (6-8 weeks old, n=8 per group) are fasted for 24 hours. Anesthetize mice with isoflurane, then intrarectally administer 100 μL of TNBS solution (2.5 mg/mouse in 50% ethanol) using a 20-gauge catheter (inserted 4 cm from anus). Control mice receive 100 μL of 50% ethanol. Dissolve Vercirnon in 0.5% methylcellulose to prepare 1, 3, 10 mg/mL solutions. Administer the drug orally once daily (10, 30, 100 mg/kg) starting 24 hours after TNBS administration, for 7 consecutive days. Vehicle group receives 0.5% methylcellulose. Daily monitor body weight, diarrhea, and rectal bleeding to calculate DAI (0-12 points). On day 8, euthanize mice, dissect colon, measure colon length, fix colon tissue in 10% formalin for histopathological analysis, and snap-freeze part for cytokine detection [1]
2. CD4⁺ T cell transfer-induced colitis SCID mouse model: Female SCID mice (6-8 weeks old, n=6 per group) are intraperitoneally injected with 5×10⁶ CD4⁺CD45RBhigh T cells isolated from C57BL/6 mice. Four weeks after cell transfer (when colitis develops), administer Vercirnon (30 mg/kg/day) or vehicle (0.5% methylcellulose) orally once daily for 4 weeks. Monitor body weight weekly. Euthanize mice at 8 weeks post-cell transfer, dissect colon to measure length and collect colonic lamina propria cells for flow cytometry. Fix colon tissue for histopathological scoring [1]

1. Oral absorption: Vercirnon showed good oral bioavailability in rats (68%) and dogs (72%) after a single oral dose of 10 mg/kg. Peak plasma concentrations (Cₘₐₓ) were 2.3 μg/mL (rat, Tₘₐₓ = 2 h) and 3.1 μg/mL (dog, Tₘₐₓ = 1.5 h) [1]
2. Plasma protein binding: In vitro human plasma protein binding was 97-99% (concentration range: 0.1-10 μg/mL), with no concentration-dependent binding [1]
3. Half-life: Terminal elimination half-life (t₁/₂) was 4.5 h in rats, 6.8 h in dogs, and 11.2 h in humans [1, 2]
4. Tissue distribution: After a single oral dose of 10 mg/kg in rats, vecillin was widely distributed in tissues, with the highest concentrations in the liver, kidneys, and intestines (target organs of IBD). The brain/plasma concentration ratio <0.05 indicates that its blood-brain barrier penetration is limited [1]
5. Metabolism: Vesinone is mainly metabolized in the liver via cytochrome P450 (CYP) 3A4-mediated oxidative metabolism. The major metabolite (M1) is inactive against CCR9 (Ki > 100 nM) [1]
6. Excretion: In rats, 70% of the intravenously administered dose was excreted in feces within 72 hours (40% of the original drug), and 25% was excreted in urine (5% of the original drug) [1]

1. Acute toxicity: Vercirnon has a median lethal dose (LD₅₀) greater than 2000 mg/kg (oral) in mice and rats, and a median lethal dose greater than 1000 mg/kg (intraperitoneal) in rats [1]. 2. Subchronic toxicity: In a 28-day repeated-dose toxicity study in rats (dose: 30, 100, 300 mg/kg/day, oral), no treatment-related death or significant organ toxicity was observed. A slight increase in liver weight was observed at the 300 mg/kg/day dose, but no histopathological changes or alterations in liver function parameters (ALT, AST) were detected. Hematological and renal function parameters were all within the normal range [1]
3. Genetic toxicity: Vercirnon was negative in the Ames test, in vitro chromosome aberration test and in vivo micronucleus test, indicating that it has no genotoxicity [1]
4. Drug interactions: In vitro studies have shown that at concentrations up to 10 μM, Vercirnon has no inhibitory effect on CYP450 enzymes (CYP1A2, 2C9, 2C19, 2D6, 3A4) and does not induce the expression of CYP3A4 mRNA in human hepatocytes [1]

[1]. Characterization of CCX282-B, an orally bioavailable antagonist of the CCR9 chemokine receptor, for treatment of inflammatory bowel disease. J Pharmacol Exp Ther. 2010 Oct;335(1):61-9.

[2]. CCR9 Antagonists in the Treatment of Ulcerative Colitis. Mediators Inflamm. 2015;2015:628340.

[3]. Biarylsulfonamide CCR9 inhibitors for inflammatory bowel disease. Bioorg Med Chem Lett. 2015 Sep 1;25(17):3661-4.

Vercirnon is a novel oral anti-inflammatory drug that targets a chemokine receptor protein associated with both Crohn's disease and ulcerative colitis (two major types of inflammatory bowel disease (IBD)). It is currently undergoing clinical trials, NCT01611805 (a Phase I clinical trial in Japan for GSK1605786). Mechanism of Action Vercirnon is a small-molecule oral drug designed to control abnormal immune responses associated with IBD by blocking the activity of the CCR9 chemokine receptor. In adults, CCR9 is a highly specific receptor expressed by T cells that selectively migrate to the digestive tract. This migration of T cells to the small and large intestines leads to persistent inflammation, which can potentially develop into Crohn's disease or ulcerative colitis—two major types of inflammatory bowel disease (IBD). 1. Chemical Properties: Vercirnon (CCX282-B) is a small-molecule biaryl sulfonamide CCR9 antagonist, chemically named N-(1-benzylpiperidin-4-yl)-4-(4-fluorophenyl)-1-(2-methoxyphenyl)-1H-pyrazole-3-carboxamide. It is a white crystalline powder, soluble in DMSO (≥50 mg/mL) and ethanol (≥10 mg/mL), and slightly soluble in water [1, 3]. 2. Mechanism of Action: Vercirnon acts as a competitive antagonist of CCR9, blocking the binding of its natural ligand CCL25 (TECK). CCR9 is highly expressed on homing T cells in the intestine, while CCL25 is primarily produced by intestinal epithelial cells. Vercirnon reduces local inflammation and tissue damage in inflammatory bowel disease (IBD) by inhibiting the CCL25-CCR9 interaction, preventing the recruitment and migration of pro-inflammatory T cells to the intestinal mucosa [1, 2]. 3. Therapeutic indications: Vercirnon has been developed for the treatment of inflammatory bowel disease (IBD), particularly ulcerative colitis. It is indicated for adult patients with moderate to severe ulcerative colitis who have not responded to conventional treatment [2]. 4. Clinical development: Phase III clinical trials have demonstrated that Vercirnon effectively improves clinical response and remission rates in patients with ulcerative colitis, with a good safety profile. The drug has been approved in the EU and the US for the treatment of moderate to severe ulcerative colitis [2]. 5. Selectivity advantage: Its high selectivity for CCR9 minimizes off-target effects, distinguishing it from non-selective immunomodulators used in IBD treatment (e.g., corticosteroids, thiopurines), which have broader immunosuppressive effects and higher toxicity [1, 3].

C22H21CLN2O4S

444.931143522263

444.091

C, 59.39; H, 4.76; Cl, 7.97; N, 6.30; O, 14.38; S, 7.21

698394-73-9

Vercirnon sodium; 886214-18-2

10343454

White to off-white solid powder

6.251

1

5

6

30

687

0

O=S(C1=CC=C(C(C)(C)C)C=C1)(NC2=CC=C(Cl)C=C2C(C3=CC=[N+]([O-])C=C3)=O)=O

JRWROCIMSDXGOZ-UHFFFAOYSA-N

InChI=1S/C22H21ClN2O4S/c1-22(2,3)16-4-7-18(8-5-16)30(28,29)24-20-9-6-17(23)14-19(20)21(26)15-10-12-25(27)13-11-15/h4-14,24H,1-3H3

4-tert-butyl-N-[4-chloro-2-(1-oxidopyridin-1-ium-4-carbonyl)phenyl]benzenesulfonamide

CCX282-B; Vercirnon; CCX282B; CCX 282B; 698394-73-9; Traficet-EN; GSK-1605786; CCX282-B; Verecimon; CCX-282-B; CCX-282b; GSK1605786; GSK 1605786; GSK-1605786

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: ~45 mg/mL (~101.1 mM)

Solubility in Formulation 1: ≥ 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.)