Long-term evaluation of E6011, an anti-fractalkine monoclonal antibody, in patients with rheumatoid arthritis inadequately responding to biological disease-modifying antirheumatic drugs.

OBJECTIVES: The objective of the study is to evaluate the long-term safety and efficacy of E6011, a humanized anti-fractalkine monoclonal antibody, in patients with rheumatoid arthritis with an inadequate response to biological disease-modifying antirheumatic drugs. METHODS: In the double-blind treatment phase (24 weeks), placebo or E6011 400 mg was administered until Week 10. Thereafter, E6011 200 mg or 400 mg was administered to Week 22. Subjects who completed the evaluation at Week 24 of the treatment phase were rolled over into the extension phase. The extension phase lasted until Week 104, and all subjects received E6011 400 mg or 200 mg every 2 weeks in an open-label manner until Week 102. RESULTS: A total of 47 subjects completed the double-blind treatment phase and were rolled over into the extension phase. In total, 46 (97.9%) subjects experienced any adverse events, and the incidence of treatment-related adverse events was 57.4%. No clear efficacy trend in the American College of Rheumatology 20% response rates was observed. CONCLUSIONS: E6011 was well tolerated in active rheumatoid arthritis patients who had shown an inadequate response to biologic disease-modifying antirheumatic drugs, but no clear benefit in the American College of Rheumatology 20% response rates was observed. Further studies are needed to clarify the clinical benefit of E6011.

Long-term safety and efficacy of E6011, an anti-fractalkine monoclonal antibody, in patients with rheumatoid arthritis inadequately responding to methotrexate.

OBJECTIVES: To evaluate the long-term safety and efficacy of E6011, a humanized anti-fractalkine monoclonal antibody, in patients with rheumatoid arthritis (RA) with an inadequate response to methotrexate (MTX). METHODS: Active RA patients with an inadequate response to MTX were randomly assigned to the E6011 or placebo group and received the study drug subcutaneously every 2 weeks during a 24-week double-blind study period. Subjects who completed evaluations at Week 24 were rolled over into the extension phase and received open-label E6011 (200 or 400 mg) every 2 weeks until Week 102. The safety analysis was conducted up to Week 104, and the efficacy analysis was conducted up to Week 84. RESULTS: A total of 169 subjects completed the double-blind treatment phase and were rolled over into the extension phase. In total, 167 (98.8%) subjects experienced any adverse events, and the incidence of treatment-related adverse events was 56.2%. The American College of Rheumatology 20 response rates were observed between 40 and 70% during the extension phase. CONCLUSIONS: E6011 was safe and well tolerated with no notable safety concerns up to 102 weeks in RA patients with an inadequate response to MTX.

Serum APOA4 Pharmacodynamically Represents Administered Recombinant Human Hepatocyte Growth Factor (E3112).

BACKGROUND: Hepatocyte growth factor (HGF) is an endogenously induced bioactive molecule that has strong anti-apoptotic and tissue repair activities. In this research, we identified APOA4 as a novel pharmacodynamic (PD) marker of the recombinant human HGF (rh-HGF), E3112. METHODS: rh-HGF was administered to mice, and their livers were investigated for the PD marker. Candidates were identified from soluble proteins and validated by using human hepatocytes in vitro and an animal disease model in vivo, in which its c-Met dependency was also ensured. RESULTS: Among the genes induced or highly enhanced after rh-HGF exposure in vivo, a soluble apolipoprotein, Apoa4, was found to be induced by rh-HGF in the murine liver. By using primary cultured human hepatocytes, the significant induction of human APOA4 was observed at the mRNA and protein levels, and it was inhibited in the presence of a c-Met inhibitor. Although mice constitutively expressed Apoa4 mRNA in the small intestine and the liver, the liver was the primary organ affected by administered rh-HGF to strongly induce APOA4 in a dose- and c-Met-dependent manner. Serum APOA4 levels were increased after rh-HGF administration, not only in normal mice but also in anti-Fas-induced murine acute liver failure (ALF), which confirmed the pharmacodynamic nature of APOA4. CONCLUSIONS: APOA4 was identified as a soluble PD marker of rh-HGF with c-Met dependency. It should be worthwhile to clinically validate its utility through clinical trials with healthy subjects and ALF patients.

Phase 1 study on the safety and efficacy of E6011, antifractalkine antibody, in patients with Crohn's disease.

BACKGROUND AND AIM: E6011 is a humanized monoclonal antibody targeting fractalkine (FKN), a CX3C chemokine, which regulates leukocyte trafficking during inflammation. We evaluated the safety and pharmacokinetic profile of E6011 in patients with Crohn's disease (CD) and also performed preliminary pharmacodynamic (PD) and efficacy assessments. METHODS: This study included a 12-week multiple ascending dose (MAD) phase (2, 5, 10, and 15 mg/kg intravenously every 2 weeks, n = 6, 8, 7, and 7, respectively) and a 40-week Extension phase (n = 12) at the same dose as the MAD phase. Serum E6011, serum total FKN (free soluble FKN and E6011-FKN complex) as a PD marker and CD activity index were evaluated. The primary outcome was safety assessment in the MAD phase. RESULTS: Twenty-seven (96%) of 28 patients had previously been treated with anti-tumor necrosis factor α agents. During the MAD phase, adverse events (AEs) occurred in 18 (64%). The most common AE was nasopharyngitis (five patients, 18%). No severe AEs occurred. Serious AEs occurred in three patients, progression of CD in two, and anemia in one. Serum E6011 concentrations increased dose-dependently after infusion and reached a plateau around 4-6 weeks. Serum total FKN rose simultaneously. Five (18%) patients developed anti-E6011 antibodies during the study. Overall, clinical response and clinical remission were observed at Week 12 in 40% (10/25) and 16% (4/25) of active CD patients, respectively. CONCLUSION: E6011 was well-tolerated and might be effective in CD patients. These findings need to be clarified in a randomized controlled study.

A phase 2 study of E6011, an anti-Fractalkine monoclonal antibody, in patients with rheumatoid arthritis inadequately responding to biological disease-modifying antirheumatic drugs.

OBJECTIVES: To evaluate the safety and efficacy of E6011, a novel humanized anti-fractalkine monoclonal antibody, in patients with active rheumatoid arthritis (RA) with an inadequate response to biological disease-modifying antirheumatic drugs (DMARDs). METHODS: Active RA patients inadequately responding to biological DMARDs were randomly assigned to placebo or E6011 400-mg group at a 1:1 ratio, and administered E6011 at weeks 0, 1, 2, and subsequently every 2 weeks. Primary endpoint was American College of Rheumatology (ACR)20 response at week 12. RESULTS: Of 64, 33 received placebo, 31 received E6011 400-mg. The ACR20 response rate at week 12 (non-responder imputation) was 27.3% and 22.6% in the placebo and E6011 groups, respectively. ACR50, ACR70 response rates at week 12 were 3.0%, 0% in the placebo and 9.7%, 3.2% in the E6011 group. Exploratory PK exposure analysis revealed that the effect of E6011 tended to be clearer in patients with higher serum trough E6011 concentration. E6011 was well tolerated with no notable safety concerns. CONCLUSIONS: E6011 400-mg was well tolerated but had no clear efficacy at week 12 in RA patients with inadequate response to biologics. Further investigations are warranted to determine the optimal clinical dose and evaluation period for E6011.

Efficacy and Safety of E6011, an Anti-Fractalkine Monoclonal Antibody, in Patients With Active Rheumatoid Arthritis With Inadequate Response to Methotrexate: Results of a Randomized, Double-Blind, Placebo-Controlled Phase II Study.

OBJECTIVE: To evaluate the efficacy and safety of E6011, a humanized IgG2 monoclonal antibody against human fractalkine (FKN), in a phase II, double-blind, placebo-controlled study in rheumatoid arthritis (RA) patients. METHODS: Patients with moderate-to-severe RA who had an inadequate response to methotrexate were randomly assigned to a placebo group or to E6011 100-mg, 200-mg, or 400/200-mg groups at a 2:1:2:2 ratio. During the 24-week period, patients received the study drug subcutaneously at weeks 0, 1, and 2 and then once every 2 weeks. The primary end point was the American College of Rheumatology 20% improvement criteria (ACR20) response rate at week 12. RESULTS: Study drugs were administered to 190 patients (placebo, n = 54; E6011 100 mg, n = 28; E6011 200 mg, n = 54; E6011 400/200 mg, n = 54), and 169 patients completed treatment. A significant difference from placebo was not found in ACR20 response rates at week 12 (37.0% [placebo], 39.3% [100 mg], 48.1% [200 mg], and 46.3% [400/200 mg], using nonresponder imputation). As a secondary end point, ACR20 response rate in the 200-mg and 400/200-mg groups attained statistical significance at week 24 (35.2% [placebo], 39.3% [100 mg], 53.7% [200 mg], and 57.4% [400/200 mg]). Subsequent exploratory subgroup analysis revealed greater efficacy of E6011, particularly in patients with a higher baseline proportion of CD16+ monocytes; ACR20 response rates in this patient subgroup at week 24 were 30.0% (placebo), 46.7% (100 mg), 57.7% (200 mg), and 69.6% (400/200 mg). E6011 administered for 24 weeks was well tolerated. CONCLUSION: This is the first evidence that E6011, a novel cell trafficking inhibitor targeting the FKN-CX3 CR1 interaction, is modestly effective with 24 weeks of treatment in RA patients, although the primary end point was not met.

Inhibition of the Progression of Skin Inflammation, Fibrosis, and Vascular Injury by Blockade of the CX3 CL1/CX3 CR1 Pathway in Experimental Mouse Models of Systemic Sclerosis.

OBJECTIVE: To assess the preclinical efficacy and mechanism of action of an anti-CX3 CL1 monoclonal antibody (mAb) in systemic sclerosis (SSc). METHODS: Cultured human dermal fibroblasts were used to evaluate the direct effect of anti-CX3 CL1 mAb on fibroblasts. In addition, bleomycin-induced and growth factor-induced models of SSc were used to investigate the effect of anti-CX3 CL1 mAb on leukocyte infiltration, collagen deposition, and vascular damage in the skin. RESULTS: Anti-CX3 CL1 mAb treatment significantly inhibited Smad3 phosphorylation (P < 0.05) and expression of type I collagen and fibronectin 1 (P < 0.01) in dermal fibroblasts stimulated with transforming growth factor ß1 (TGFß1). In the bleomycin model, daily subcutaneous bleomycin injection increased serum CX3 CL1 levels (P < 0.05) and augmented lesional CX3 CL1 expression. Simultaneous administration of anti-CX3 CL1 mAb or CX3 CR1 deficiency significantly suppressed the dermal thickness, collagen content, and capillary loss caused by bleomycin (P < 0.05). Injection of bleomycin induced expression of pSmad3 and TGFß1 in the skin, which was inhibited by anti-CX3 CL1 mAb. Further, the dermal infiltration of CX3 CR1+ cells, macrophages (inflammatory and alternatively activated [M2-like] subsets), and CD3+ cells significantly decreased following anti-CX3 CL1 mAb therapy (P < 0.05), as did the enhanced skin expression of fibrogenic molecules, such as thymic stromal lymphopoietin and secreted phosphoprotein 1 (P < 0.05). However, the treatment did not significantly reduce established skin fibrosis. In the second model, simultaneous anti-mCX3 CL1 mAb therapy significantly diminished the skin fibrosis induced by serial subcutaneous injection of TGFß and connective tissue growth factor (P < 0.01). CONCLUSION: Anti-CX3 CL1 mAb therapy may be a novel approach for treating early skin fibrosis in inflammation-driven fibrotic skin disorders such as SSc.

Anti-Apoptotic Effects of Recombinant Human Hepatocyte Growth Factor on Hepatocytes Were Associated with Intrahepatic Hemorrhage Suppression Indicated by the Preservation of Prothrombin Time.

Hepatocyte growth factor (HGF) is an endogenously expressed bioactive substance that has a strong anti-apoptotic effect. In this study, we biochemically and histologically characterized the effects of rh-HGF on in vitro human hepatocyte injury and mouse acute liver failure (ALF) models, both of which were induced by antibody-mediated Fas signaling. rh-HGF inhibited intracellular caspase-3/7 activation and cytokeratin 18 (CK-18) fragment release in both models. Histologically, rh-HGF dramatically suppressed parenchymal damage and intrahepatic hemorrhage. Among the laboratory parameters, prothrombin time (PT) was strongly preserved by rh-HGF, and PT was well correlated with the degree of intrahepatic hemorrhage. These results showed that the anti-apoptotic effect of rh-HGF on hepatocytes coincided strikingly with the suppression of intrahepatic hemorrhage. PT was considered to be the best parameter that correlated with the intrahepatic hemorrhages associated with hepatocellular damage. The action of rh-HGF might derive not only from its anti-apoptosis effects on liver parenchymal cells but also from its stabilization of structural and vasculature integrity.

Pharmacokinetics, Pharmacodynamics, and Safety of E6011, a Novel Humanized Antifractalkine (CX3CL1) Monoclonal Antibody: A Randomized, Double-Blind, Placebo-Controlled Single-Ascending-Dose Study.

E6011 is a novel humanized antifractalkine (FKN) monoclonal antibody being developed as a therapeutic target for Crohn's disease, rheumatoid arthritis, and primary biliary cholangitis. This study was a randomized, double-blind, placebo-controlled single-ascending-dose study of intravenous administration of E6011 (0.0006-10 mg/kg) in healthy Japanese adult men (n = 64). The starting dose was the minimum anticipated biological effect level (MABEL). MABEL was estimated by extrapolating results of a pharmacokinetic/pharmacodynamic (PK/PD) model relating E6011 exposure and suppression of free soluble FKN using data obtained from cynomolgus monkeys. Safety assessments consisted of monitoring and recording adverse events, laboratory tests, vital signs, intensive electrocardiograms, and chest x-rays. Blood samples to determine PK, PD (serum total FKN concentration), and serum anti-E6011 antibody were collected. Noncompartmental analysis was used to derive PK parameters. Single intravenous infusions of E6011 were safe and well tolerated in healthy subjects. Serum E6011 concentrations showed triphasic elimination. An increase in serum total FKN concentration was observed, confirming target engagement. The dose strategy for patient studies is to select regimens that will attain a minimum serum E6011 exposure of 10 µg/mL, identified as the minimum concentration needed to saturate the target-mediated elimination pathway. Model-based drug development from preclinical stage was successful in identifying dose regimens for clinical testing.

Safety, pharmacokinetics, and efficacy of E6011, an antifractalkine monoclonal antibody, in a first-in-patient phase 1/2 study on rheumatoid arthritis.

OBJECTIVE: Fractalkine (CX3CL1/FKN) is a chemokine that regulates chemotaxis and adhesion of CX3C chemokine receptor 1 (CX3CR1)-expressing inflammatory cells. We conducted the first phase 1/2, open-label, multiple ascending dose study of E6011, a humanized anti-FKN monoclonal antibody, in Japanese rheumatoid arthritis (RA) patients (clinicaltrial.gov identifier: NCT02196558). METHODS: Active RA patients with an inadequate response or intolerance to methotrexate or tumor necrosis factor (TNF) inhibitor received E6011 at week 0, 1, 2, and thereafter every 2 weeks for 12 weeks. RESULTS: Twelve, 15, and 10 subjects were enrolled in the 100, 200, and 400 mg cohorts, respectively. No severe adverse events (AEs) or deaths occurred, and no major differences were observed in the incidence or severity of AEs across the cohorts. Serum E6011 concentrations increased dose dependently. American College of Rheumatology (ACR) 20, 50, and 70 responses at week 12 were 75.0%, 33.3%, and 8.3% in the 100 mg cohort; 66.7%, 20.0%, and 13.3% in the 200 mg cohort; and 60.0%, 30.0%, and 20.0% in the 400 mg cohort, respectively. CONCLUSIONS: E6011 appeared to be safe and well tolerated in RA patients during this 12-week treatment period, suggesting that E6011 has an effective clinical response in active RA patients.

The recovery of the PT-INR to less than 1.3 predicts survival in patients with severe acute liver injury.

BACKGROUND: Acute liver failure is a potentially fatal disease of various etiologies for which liver transplantation is the only known curative treatment. Although the decision-making on transplantation is largely dependent on the severity of liver injury (based on predicting a fatal outcome), a statistical analysis to predict "survival" has not been extensively conducted. In this study, we investigate the medical history of patients in two distinct areas of Japan with the aim of identifying the predictors of survival in patients with acute liver injury (ALI). METHODS: Datasets of 301 patients with ALI in two distinct areas (93 in southern Kyushu and 208 in northern Tohoku) of Japan, who were treated from 2004 to 2014, were included in the analysis. RESULTS: Among the enrolled 301 cases, 263 patients survived without transplantation. A PT-INR of ≥ 1.3 during the clinical course was found to be adequate for predicting a poor prognosis, because all of the fatal cases emerged from this population (hazard ratios: southern Kyushu, 0.2827; northern Tohoku, 0.1862). All surviving patients showed a reduction in their PT-INR during treatment, whereas the PT-INR did not decrease in the patients with a poor prognosis. A PT-INR of < 1.3 on days 7 and 8 efficiently predicted transplant-free survival (log-rank test: southern Kyushu, P = 0.0030; northern Tohoku, P = 0.0022). CONCLUSIONS: A PT-INR of ≥ 1.3 during the clinical course might identify cases with a poor prognosis, while the recovery of the PT-INR to < 1.3 predicts transplant-free survival.

Inhibition of CCL20 increases mortality in models of mouse sepsis with intestinal apoptosis.

BACKGROUND: CC chemokine ligand 20 (CCL20) and CC chemokine receptor 6 are believed to stimulate the recruitment of neutrophils and activation of macrophages against bacterial pathogens through the activation of T helper cells. We analyzed the role of CCL20 in the acute phase of sepsis. METHODS: The effect of a neutralizing, anti-mouse CCL20 monoclonal antibody (mAb) was examined in 2 murine models of sepsis: Cecal ligation and puncture (CLP) and Escherichia coli peritonitis. Immune cell migration, bacterial clearance, and expression of 17 cytokines and 5 chemokines were quantified in E coli-induced peritonitis. Expression of CCL20 in various tissues was determined, and apoptotic cells in jejunum were measured. RESULTS: Anti-CCL20 mAb increased mortality in CLP and E coli peritonitis (P = .029 and .024, respectively by Kaplan-Meier method and log-rank test). The 48-hour survival rate in anti-CCL20 mAb- and control immunoglobulin (Ig)G-treated mice was 37% (11/30) vs 62% (18/29) in CLP and 28% (11/40) vs 48% (19/40) in bacterial peritonitis. Neutralization of CCL20 showed no effect on leukocyte infiltration into the peritoneal cavity or bacterial clearance at 24 hours. CCL20 was induced strongly and predominantly in jejunum after bacterial infection, and neutralizing CCL20 increased apoptosis of epithelial cells in jejunum crypt. Inhibition of CCL20 increased serum tumor necrosis factor (TNF)-α (3.3-fold greater than control mice) and decreased serum interleukin (IL)-1α and IL-6. CONCLUSION: Neutralization of CCL20 before induction of sepsis increased mortality during sepsis accompanied with increasing epithelial apoptosis in the jejunum and augmenting serum TNF-α.

Chemokines as novel therapeutic targets for inflammatory bowel disease.

The inflammatory bowel diseases (IBD) such as Crohn's disease (CD) and ulcerative colitis (UC) are illness characterized by a chronic clinical course of relapse and remission associated with self-destructive inflammation of the gastrointestinal tract. In both UC and CD, leukocyte infiltration into the intestine is fundamental event in disease development and progression where the chemokines and their receptors are orchestrating the tissue-specific and the cell type-selective trafficking of leukocytes. In this review, we will discuss the homeostatic and inflammatory roles of the chemokines and their receptors with their potentials and promise as molecular targets for therapeutic interventions in human IBD, focusing on the recently identified role of the CX3CL1-CX3CR1 axis, as well as the CCL20-CCR6, CCL25-CCR9, and CXCL10-CXCR3 pathways.

Expansion of lung V alpha 14 NKT cells by administration of alpha-galactosylceramide-pulsed dendritic cells.

NKT cells, a novel murine lymphoid lineage bearing an invariant T cell receptor encoded by V alpha 14 and J alpha 281 gene segments, recognize a specific ligand glycolipid, alpha-galactosylceramide (alpha-GalCer) in a CD1d-dependent manner. Recent research has revealed that activated V alpha 14 NKT cells have dramatic antitumor effects against a wide variety of tumor cell lines in vivo and in vitro. Here, we demonstrate strong in vivo antitumor effects brought about by treatment with alpha-GalCer-pulsed dendritic cells in comparison with in vitro-activated V alpha 14 NKT cells. Furthermore, we show a significant expansion of endogenous V alpha 14 NKT cells in the lung following the administration of alpha-GalCer-pulsed dendritic cells. The feasibility of immunotherapy with alpha-GalCer-pulsed dendritic cells is discussed.