E3710, a new proton pump inhibitor, with a long-lasting inhibitory effect on gastric acid secretion.

We have investigated the pharmacology of sodium (R)-2-[4-(2,2-dimethyl-1,3-dioxan-5-yl) methoxy-3,5-dimethylpyridin-2-yl]methylsulfinyl-1H-benzimidazol (E3710), a new proton pump inhibitor (PPI), and its effect on gastric acid secretion. E3710 irreversibly inhibited H(+),K(+)-ATPase activity in pig gastric vesicles with an acidic internal environment with an IC(50) of 0.28 microM. Administration of E3710 (0.1, 0.2, 0.4, and 0.8 mg/kg; n = 6) intraduodenally in a gastric fistula model in dogs inhibited histamine-stimulated gastric acid secretion at 0 to 2 and 24 to 26 h after administration with ED(50) values of 0.18 and 0.22 mg/kg, respectively. The inhibition by E3710 was 2.3 times more potent than that of another representative PPI, esomeprazole (0.2, 0.4, 0.8, and 1.6 mg/kg; n = 6) at 0 to 2 h after administration (ED(50) = 0.40 mg/kg) and 2.8 times more potent at 24 to 26 h (ED(50) = 0.71 mg/kg). In the gastric fistula dogs, the intragastric pH was >or=4 for 17% (n = 27) of a 24-h period with vehicle alone, but when E3710 was administered, at 0.2 (n = 4), 0.4 (n = 8), and 0.8 mg/kg (n = 5), the pH was >or=4 for 40, 79, and 88% of a day, respectively. The corresponding values for esomeprazole at 0.8 (n = 4) and 1.6 mg/kg (n = 8) were 55 and 59%, respectively. In a crossover study with vehicle, E3710 at 0.4 mg/kg and esomeprazole at 1.6 mg/kg (n = 6), E3710 increased the intragastric pH to >4 for 82% of a day compared with 61% of a day with esomeprazole. These results show that E3710 is a long-acting inhibitor of gastric acid secretion and a promising novel therapy for acid-related diseases, such as gastroesophageal reflux disease.

Calreticulin and integrin alpha dissociation induces anti-inflammatory programming in animal models of inflammatory bowel disease.

Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease, is a chronic intestinal inflammatory condition initiated by integrins-mediated leukocyte adhesion to the activated colonic microvascular endothelium. Calreticulin (CRT), a calcium-binding chaperone, is known as a partner in the activation of integrin α subunits (ITGAs). The relationship between their interaction and the pathogenesis of IBD is largely unknown. Here we show that a small molecule, orally active ER-464195-01, inhibits the CRT binding to ITGAs, which suppresses the adhesiveness of both T cells and neutrophils. Transcriptome analysis on colon samples from dextran sodium sulfate-induced colitis mice reveals that the increased expression of pro-inflammatory genes is downregulated by ER-464195-01. Its prophylactic and therapeutic administration to IBD mouse models ameliorates the severity of their diseases. We propose that leukocytes infiltration via the binding of CRT to ITGAs is necessary for the onset and development of the colitis and the inhibition of this interaction may be a novel therapeutic strategy for the treatment of IBD.

E7090, a Novel Selective Inhibitor of Fibroblast Growth Factor Receptors, Displays Potent Antitumor Activity and Prolongs Survival in Preclinical Models.

The FGFR signaling pathway has a crucial role in proliferation, survival, and migration of cancer cells, tumor angiogenesis, and drug resistance. FGFR genetic abnormalities, such as gene fusion, mutation, and amplification, have been implicated in several types of cancer. Therefore, FGFRs are considered potential targets for cancer therapy. E7090 is an orally available and selective inhibitor of the tyrosine kinase activities of FGFR1, -2, and -3. In kinetic analyses of the interaction between E7090 and FGFR1 tyrosine kinase, E7090 associated more rapidly with FGFR1 than did the type II FGFR1 inhibitor ponatinib, and E7090 dissociated more slowly from FGFR1, with a relatively longer residence time, than did the type I FGFR1 inhibitor AZD4547, suggesting that its kinetics are more similar to the type V inhibitors, such as lenvatinib. E7090 showed selective antiproliferative activity against cancer cell lines harboring FGFR genetic abnormalities and decreased tumor size in a mouse xenograft model using cell lines with dysregulated FGFR Furthermore, E7090 administration significantly prolonged the survival of mice with metastasized tumors in the lung. Our results suggest that E7090 is a promising candidate as a therapeutic agent for the treatment of tumors harboring FGFR genetic abnormalities. It is currently being investigated in a phase I clinical trial. Mol Cancer Ther; 15(11); 2630-9. ©2016 AACR.

The novel and orally active thrombin receptor antagonist E5555 (Atopaxar) inhibits arterial thrombosis without affecting bleeding time in guinea pigs.

Thrombin is a powerful agonist for platelets, the action of which is mediated by the thrombin receptor protease-activated receptor-1 (PAR-1). Recently, we discovered that E5555 (1-(3-tert-butyl-4-methoxy-5-morpholinophenyl)-2-(5,6-diethoxy-7-fluoro-1-imino-1,3-dihydro-2H-isoindol-2-yl) ethanone hydrobromide) is a potent thrombin receptor antagonist. We evaluated the anti-platelet and anti-thrombotic effects of E5555. E5555 inhibited the binding of a high-affinity thrombin receptor-activating peptide ([(3)H]haTRAP) to PAR-1 with a half maximal inhibitory concentration (IC(50)) value of 0.019µM. E5555 showed potent inhibitory effects on human platelet aggregation induced by thrombin and TRAP with IC(50) values of 0.064 and 0.031µM, respectively, but had no effect on platelet aggregation induced by either ADP or collagen. Similarly, E5555 showed potent and selective inhibitory effects on guinea pig platelet aggregation induced by thrombin and TRAP with IC(50) values of 0.13 and 0.097µM, respectively. The antithrombotic activity of E5555 in vivo was evaluated in a photochemically-induced thrombosis (PIT) model using guinea pigs. Oral administration of E5555 at 30 and 100mg/kg prolonged the time to occlusion by 1.8-fold and 2.4-fold, respectively, compared with controls. Furthermore, E5555 did not prolong bleeding time in guinea pigs at the highest tested dosage of 1000mg/kg. The drug interactions between E5555 and tissue plasminogen activator (tPA) were evaluated. Intravenous administration of 1mg/kg tPA significantly prolonged bleeding time, and its effects were not altered by the oral co-administration of 300mg/kg E5555. These results suggest that E5555 could be a therapeutic option for atherothrombotic disease.

Oral administration of the thrombin receptor antagonist E5555 (atopaxar) attenuates intimal thickening following balloon injury in rats.

Thrombin is a powerful agonist for a variety of cellular responses including platelet aggregation and vascular smooth muscle cell (SMC) proliferation. These actions are mediated by a thrombin receptor known as protease-activated receptor-1 (PAR-1). Recently we discovered that 1-(3-tert-butyl-4-methoxy-5-morpholinophenyl)-2-(5,6-diethoxy-7-fluoro-1-imino-1,3-dihydro-2H-isoindol-2-yl)ethanone hydrobromide (E5555, atopaxar) is a potent and selective thrombin receptor antagonist. This study characterized the pharmacological effects of E5555 on SMC proliferation in vitro and in a rat model of intimal thickening after balloon injury in vivo. E5555 selectively inhibited rat aortic SMC proliferation induced by thrombin and thrombin receptor-activating peptide (TRAP) with half maximal inhibitory concentration (IC(50)) values of 0.16 and 0.038 µM, respectively. E5555 did not inhibit rat SMC proliferation induced by basic fibroblast growth factor (bFGF) and platelet-derived growth factor (PDGF) at concentrations up to 1µM. In addition, E5555 inhibited human aortic SMC proliferation induced by thrombin at concentrations of 0.3 and 3units/ml with IC(50) values of 0.028 and 0.079 µM, respectively, whereas it did not affect bFGF-induced proliferation at concentrations up to 1µM. Repeated oral administration of 30 mg/kg E5555 (once daily for 16 days) significantly reduced neointimal formation in the balloon-injured rat arterial model. These results suggested that a PAR-1 antagonist could be effective for treating restenosis following vascular intervention in addition to preventing thrombus formation. E5555 could thus have therapeutic potential for restenosis and chronic atherothrombotic disease.