Toshihiro Nanki

Fractalkine/CX3CL1 in rheumatoid arthritis.

Abstract Fractalkine is a CX3C chemokine that exists in both membrane-bound and soluble forms. Interaction between fractalkine and its unique receptor (CX3CR1) induces cell adhesion, chemotaxis, crawling, “accessory cell” activity, and survival. The serum level of fractalkine is elevated in patients with rheumatoid arthritis (RA) and is correlated with disease activity. Peripheral blood CD16+ u2009monocytes and a subset of T cells express CX3CR1, while fractalkine is expressed on fibroblast-like synoviocytes and endothelial cells in the synovial tissue of patients with RA. Fractalkine expression is enhanced by tumor necrosis factor-α and interferon-γ, and it promotes the migration of monocytes, T cells, and osteoclast precursors into RA synovial tissue. Fractalkine also induces the production of inflammatory mediators by macrophages, T cells, and fibroblast-like synoviocytes. Moreover, fractalkine promotes angiogenesis and osteoclastogenesis. In an animal model of RA, arthritis was improved by the abrogation of fractalkine. Recently, a clinical trial of an anti-fractalkine monoclonal antibody for the treatment of RA commenced in Japan. We review the multiple roles of fractalkine in the pathogenesis of RA and its potential as a therapeutic target for this disease.

The growth factor midkine may play a pathophysiological role in rheumatoid arthritis

Abstract Objectives: Midkine (MK) is involved in cell proliferation, differentiation, migration, and survival. In this study, we measured serum MK levels in rheumatoid arthritis (RA) and investigated the correlation of serum MK with RA disease activity. Expression and effect of MK in RA synovial tissue were also examined. Methods: Serum MK and production of inflammatory mediators by rheumatoid synovial fibroblasts (RSFs) were measured by enzyme-linked immunosorbent assay. MK expression in synovial tissue was examined by immunohistochemistry. MK receptor expression was analyzed by RT-PCR and Western blotting. Results: RA patients had a significantly higher serum MK level than healthy controls. In RA patients, the MK level was correlated with DAS28-ESR, disability index of the Health Assessment Questionnaire, and rheumatoid factor level. The serum MK level tended to be decreased by anti-TNF therapy. MK was expressed by synovial lining cells in RA synovial tissues and it enhanced the production of IL-6, IL-8, and CCL2 by RSFs. RSFs expressed LDL receptor-related protein 1, candidate receptor for MK. Conclusions: The serum MK level could be a marker of disease activity in RA and an indicator of a poor prognosis. MK may have a role in the pathogenesis of RA via induction of inflammatory mediators.

Optimal regimens of sulfamethoxazole-trimethoprim for chemoprophylaxis of Pneumocystis pneumonia in patients with systemic rheumatic diseases: results from a non-blinded, randomized controlled trial

BackgroundSulfamethoxazole-trimethoprim (SMX/TMP) is a standard drug for the prophylaxis of Pneumocystis pneumonia (PJP) in immunosuppressed patients with systemic rheumatic diseases, but is sometimes discontinued due to adverse events (AEs). The objective of this non-blinded, randomized, 52-week non-inferiority trial was to quest an effective chemoprophylaxis regimen for PJP with a low drug discontinuation rate. Results at week 24 were reported.MethodsAdult patients with systemic rheumatic diseases who started prednisolone ≥0.6xa0mg/kg/day were randomized into three dosage groups: a single-strength group (SS, SMX/TMP of 400/80xa0mg daily), half-strength group (HS, 200/40xa0mg daily), and escalation group (ES, started with 40/8xa0mg daily, increasing incrementally to 200/40xa0mg daily). The primary endpoint was non-incidence rates (non-IR) of PJP at week 24.ResultsOf 183 patients randomly allocated at a 1:1:1 ratio into the three groups, 58 patients in SS, 59 in HS, and 55 in ES started SMX/TMP. A total of 172 patients were included in the analysis. No cases of PJP were reported up to week 24. Estimated non-IR of PJP in patients who received daily SMX/TMP of 200/40xa0mg, either starting at this dose or increasing incrementally, was 96.8–100% using the exact confidence interval as a post-hoc analysis. The overall discontinuation rate was significantly lower with HS compared to SS (pu2009=u20090.007). The discontinuation rates due to AEs were significantly lower with HS (pu2009=u20090.006) and ES (pu2009=u20090.004) compared to SS. The IR of AEs requiring reduction in the dose of SMX/TMP (pu2009=u20090.009) and AEs of special interest (pu2009=u20090.003) were different among the three groups with significantly higher IR in SS compared to HS and ES.ConclusionsAlthough there were no PJP cases, the combined group of HS and ES had an excellent estimated non-IR of PJP andxa0both were superior in safety to SS. From the perspective of feasibility and drug discontinuation rates, the daily half-strength regimen was suggested to be optimal for prophylaxis of PJP in patients with systemic rheumatic diseases.Trial registrationThe University Hospital Medical Information Network Clinical Trials Registry number is UMIN000007727, registered 10 April 2012.

Resistin upregulates chemokine production by fibroblast-like synoviocytes from patients with rheumatoid arthritis

BackgroundAdipokines are bioactive hormones secreted by adipose tissues. Resistin, an adipokine, plays important roles in the regulation of insulin resistance and inflammation. Resistin levels are known to be increased in the serum and synovial fluid of rheumatoid arthritis (RA) patients. However, the pathogenic role of resistin in RA has not yet been elucidated.MethodsThe expression of resistin and adenylate cyclase-associated protein 1 (CAP1), a receptor for resistin, was examined immunohistochemically in synovial tissue. CAP1 expression in in vitro cultured fibroblast-like synoviocytes (FLSs) was assessed with a reverse transcription-polymerase chain reaction (PCR) and western blotting. The gene expression of resistin-stimulated FLSs was evaluated by RNA sequencing (RNA-Seq) and quantitative real-time PCR. Concentrations of chemokine (C-X-C motif) ligand (CXCL) 8, chemokine (C-C motif) ligand (CCL) 2, interleukin (IL)-1β, IL-6 and IL-32 in culture supernatants were measured by enzyme-linked immunosorbent assay. Small interfering RNA (siRNA) for CAP1 was transfected into FLSs in order to examine inhibitory effects.ResultsThe expression of resistin and CAP1 in synovial tissue was stronger in RA than in osteoarthritis (OA). Resistin was expressed by macrophages in the RA synovium, while CAP1 was expressed by macrophages, FLSs and endothelial cells. In vitro cultured RA FLSs also expressed CAP1. RNA-Seq revealed that the expression levels of 18 molecules were more than twofold higher in resistin-stimulated FLSs than in unstimulated FLSs. Seven chemokines, CXCL1, CXCL2, CXCL3, CXCL5, CXCL6, CXCL8, and CCL2, were included among the 18 molecules. Increases induced in the expression of CXCL1, CXCL8, and CCL2 by the resistin stimulation were confirmed by real-time PCR. The stimulation with resistin increased the protein levels of CXCL8 and CCL2 produced by RA FLSs, and the upregulated expression of CXCL8 was inhibited by the abrogation of CAP1 by siRNA for CAP1. Production of IL-6 by FLSs was also increased by resistin. Expression of IL-1β and IL-32 was not detected by ELISA.ConclusionsResistin contributes to the pathogenesis of RA by increasing chemokine production by FLSs via CAP1 in synovial tissue.

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

Abstract 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 400u2009mg 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 100u2009mg cohort; 66.7%, 20.0%, and 13.3% in the 200u2009mg cohort; and 60.0%, 30.0%, and 20.0% in the 400u2009mg 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.

THU0074 Different risk factors are associated with serious infection in rheumatoid arthritis patients with and without pulmonary comorbidities; Analyses from the real database

Background Pulmonary comorbidity (PC) is a clinically important complication in patients with rheumatoid arthritis (RA) because PC has been recognized as one of the prognostic factors for RA1-3 and often prevents patients from receiving aggressive treatments for RA. Furthermore, Japanese may be more susceptible to development of PC than other ethnic groups4. However, a difference in risk factors for serious infections (SIs) between patients with and without PC has not been thoroughly studied yet. Objectives To compare risk factors for SIs between patients with and without PC using the Registry of Japanese RA patients for Long-term safety (REAL) database. Methods This study included Japanese RA patients who started biologics or nonbiological DMARDs at the enrollment in the REAL database. Case report forms were filed by attending physicians every 6 months up to 5 years for each patient in the REAL. Observation period of this study started at the enrollment in the REAL and was censored after 2 years. We analyzed types and incidence rates of SIs. Analysis included 360 patients with PC [PC group, 589 patient-years] and 1,384 patients without PC (non-PC group, 2,325 patient-years). PC included interstitial pneumonia (193), obstructive pulmonary diseases (30), bronchiectasis (20),and other pulmonary diseases. To identify risk factors and hazard ratio (HR) for SIs in each group, Cox proportional-hazard regression analysis was applied. Results At baseline, patients were older (p<0.001) and percentage of male was higher (p<0.001) in the PC group. The PC group had higher DAS28 (3/CRP) (p<0.001) and poorer physical function (p<0.001), and received lower dosage of methotrexate (p<0.001). Percentage of patients receiving prednisolone (PSL) more than 7.5mg/day (p=0.001) and that of patients who had diabetes mellitus (DM) (p<0.001) were also higher in the PC group. There were 65 SIs (40 for pulmonary, 11 for skin and subcutaneous tissue, 14 other infections) in the PC group, and 89 SIs (42 for pulmonary, 21 for skin and subcutaneous tissue, 26 other infections) in the non-PC group. The crude incidence rate ratios comparing the PC group with the non-PC group were 2.8 (2.1-4.0) for all SIs and 3.7 (2.4-5.8) for pulmonary infections. Multivariate analyses revealed that age by decade (HR [95% CI], 1.8 [1.4-2.3]), presence of DM (1.9 [1.0-3.4]) and use of PSL ≥7.5mg/day (2.1 [1.2-3.7]) were significant risk factors for SIs in the PC group, while age by decade (1.5 [1.1-2.0]), Steinbrocker’s stage (III or IV) (1.9 [1.0-3.4]), and DAS28 (3/CRP) (1.4 [1.1-1.7]) in the non-PC group. HR of higher dosage of PSL in the PC group and those of biologics in both groups were not significant. Conclusions Different risk factors were associated with SIs between RA patients with and without PC. References Rheumatology 2010; 49:1483-1489 Arthritis Rheum 2010; 62:1583-1591 Ann Rhum Dis 2010; 69:1086-1091 Nat. Rev. Rheumatol 2010; 6:644-652 Disclosure of Interest R. Sakai: None Declared, M. Tanaka: None Declared, T. Nanki: None Declared, H. Yamazaki: None Declared, K. Watanabe: None Declared, R. Koike: None Declared, N. Miyasaka Grant/Research support from: Abbott Japan Co., Ltd., Astellas Pharma Inc., MSD K.K., Chugai Pharmaceutical Co., Ltd., Daiichi Sankyo Co., Ltd., Eizai Co., Ltd., Janssen Pharmaceutical K.K., Mitsubishi Tanabe Pharma Co., Takeda Pharmaceutical Co., Ltd., and Teijin Pharma Ltd., Consultant for: Janssen Pharmaceutical K.K., Bristol Myers Squibb K.K., Otsuka Pharmaceutical Co. Ltd., Mitsubishi Tanabe Pharma Co., Abbott Japan Co., Ltd., M. Harigai Grant/Research support from: Abbott Japan Co., Ltd., Astellas Pharma Inc., Bristol Myers Squibb K.K., Chugai Pharmaceutical Co., Ltd., Eisai Co., Ltd., Mitsubishi Tanabe Pharma Co., Santen Pharmaceutical Co., Ltd, Takeda Pharmaceutical Co., Ltd., and Pfizer Japan Inc., Consultant for: Abbott Japan Co., Ltd., Astellas Pharma Inc., Bristol Myers Squibb K.K., Chugai Pharmaceutical Co., Ltd., Eisai Co., Ltd., Janssen Pharmaceutical K.K., Mitsubishi Tanabe Pharma Co., Santen Pharmaceutical Co., Ltd, Takeda Pharmaceutical Co., Ltd., and Pfizer Japan Inc.

Low body mass index and lymphocytopenia associate with Mycobacterium avium complex pulmonary disease in patients with rheumatoid arthritis

Abstract Objectives: Patients with rheumatoid arthritis (RA) are at an increased risk of Mycobacterium avium complex pulmonary disease (MAC-PD). We aimed to identify factors associated with MAC-PD in RA patients, and investigate their clinical significance for diagnosis of this disease. Methods: We examined 396 patients with RA for the presence of MAC-PD, using the criteria of the American Thoracic Society and conducted three years of follow-up on these patients. Multivariate logistic analyses were employed for selecting factors associated with MAC-PD. We developed a point system based on these factors which we call MAC-PD score to improve diagnosis of MAC-PD. Results: During this study, 14 out of 396 patients were newly diagnosed with MAC-PD. Multivariate analyses revealed body mass index (BMI)u2009<18.0u2009kg/m2 and lymphocyte count <1500/μl were associated with MAC-PD in RA patients. Points were assigned to them and totalled to provide the MAC-PD score. Among 20 patients with high-resolution computer tomography images consistent with MAC-PD, the scores were significantly higher in 14 patients with MAC-PD than those in six patients without MAC-PD. Conclusion: Using these data, in the forms of the MAC-PD score, could help to identify patients who should be considered for bronchoscopy more selectively.

Successful Treatment of IgA Vasculitis Complicated with Bowel Perforation and Crescentic Glomerulonephritis by Combination Therapy of Glucocorticoid, Cyclosporine and Factor XIII Replacement

We report the findings of an 18-year-old boy with immunoglobulin A vasculitis (IgAV) complicated with bowel perforation and nephritis. He presented with abdominal pain, arthralgia and palpable purpura. Massive proteinuria developed during his clinical course. The patient was treated successfully using combination therapy of glucocorticoid (GC), cyclosporine (CYA) and factor XIII (F XIII) replacement. A standard treatment strategy for severe IgAV patients has not been established due to its rarity. Combination therapy using GC, CYA and F XIII replacement should be considered for severe IgAV patients.

Glucocorticoid therapy causes contradictory changes of serum Wnt signaling-related molecules in systemic autoimmune diseases

The objective of this study was to investigate the clinical significance of the Wnt/β-catenin signaling pathway in glucocorticoid-induced osteoporosis. A total of 91 patients with systemic autoimmune diseases who received initial glucocorticoid therapy with prednisolone (30–60xa0mg daily) were prospectively enrolled. We measured serum levels of N-terminal peptide of type I procollagen (P1NP), bone alkaline phosphatase (BAP), tartrate-resistant acid phosphatase isoform 5b (TRACP-5b), N-telopeptide cross-linked type I collagen (NTX), sclerostin, Dickkopf-1 (Dkk-1), and Wnt3a before starting glucocorticoid therapy and every week for 4xa0weeks after its initiation. The effects of dexamethasone on expression of mRNA and protein of sclerostin and Dkk-1 by cultured normal human osteoblasts (NHOst) were evaluated by RT-PCR and ELISA, respectively. Serum levels of sclerostin and Dkk-1 increased significantly by 1xa0week of glucocorticoid therapy and then decreased from the second week onward. Serum Wnt3a tended to decrease and serum P1NP showed a significant decrease. However, TRACP-5b was significantly elevated from the first week of treatment onwards. In vitro study, dexamethasone increased Dkk-1 mRNA expression in cultured NHOst, but sclerostin mRNA was not detected. Dexamethasone also increased Dkk-1 protein production by osteoblasts, whereas sclerostin protein was not detected. Bone formation might be impaired at least in the first week of the initiation of glucocorticoid therapy by increase of the serum Wnt signaling inhibitors; however, their reductions in the subsequent weeks were contradictory to the maintained suppression of the bone formation markers after glucocorticoid therapy for patients with systemic autoimmune diseases.

SAT0187 Safety, pharmacokinetics and efficacy of e6011, an anti-fractalkine monoclonal antibody, in a first-in-patient phase 1/2 study in rheumatoid arthritis; addtional data of 400 mg cohort

Background Fractalkine (CX3CL1, designated as FKN hereafter) is the sole member of the CX3C-chemokine which leads to dual actions, chemotaxis and cell adhesion for leukocytes expressing the cognate receptor, CX3CR1, during their migration. Accumulating evidence is telling that FKN-CX3CR1 axis plays a pivotal role in leukocyte/lymphocyte accumulation in inflamed tissues in RA1. Last year, we presented an interim report (up to 200 mg cohort) of Phase 1/2 study of E6011, a novel humanized anti-FKN monoclonal antibody, for active Japanese RA patients2. Objectives To evaluate safety, pharmacokinetics and efficacy of E6011 with the dosage up to 400 mg in a Phase 1/2, open-label, multiple ascending dose study in RA patients (NCT02196558). Methods Active RA patients with inadequate response (IR) to MTX or TNF inhibitors (TNFi) were received 7 consecutive doses (subcutaneous) of E6011 at week 0, 1, 2 and thereafter every 2 weeks up to week 10. The safety, pharmacokinetics and efficacy up to week 12 were evaluated. Results Twelve, 15 and 10 subjects were enrolled in the cohort of 100, 200 and 400 mg dosage, respectively, in total 37 subjects received repeated subcutaneous (SC) administrations of E6011. As a result, repeated dose of E6011 was found safe and well tolerated. The incidence of adverse event (AE), treatment-related AE and serious AE were 56.8%, 29.7% and 5.4%, respectively. AEs occurring in ≥2 subjects were nasopharyngitis, Injection site erythema, headache and oropharyngeal pain, among which there were no severe AEs, serious infections and deaths. No significant differences were observed in the incidence or severity of AEs across the cohorts. After starting multiple SC injection of E6011, serum E6011 concentration reached steady-state at week 2, and its level was maintained up to week 12 in all cohorts. Clinical outcome was also available in the study in which response rates of ACR20, 50 and 70 at week 12 calculated using the non-responder imputation (NRI) were 75.0%, 33.3%, 8.3% in 100 mg cohort, 66.7%, 20.0%, 13.3% in 200 mg cohort and 60.0%, 30.0%, 20.0% in 400 mg cohort, respectively. The percentage of patients categorized “good response” with the EULAR response criteria at week 12 (NRI) were 16.7% in 100 mg cohort, 20% in 200 mg cohort and 40% in 400 mg cohort. Conclusions E6011 was safe and well tolerated, and the study demonstrated a promising efficacy of E6011 in active RA patients with MTX- or TNFi-IR. The results obtained suggest that a novel approach to target FKN/CX3CR1 interaction will be clinically beneficial for RA, and support to conduct phase 2 clinical trials in which the efficacy and safety should be confirmed in a placebo controled double-blind manner. References Nanki T. Arthritis Rheum. 2002; 46(11):2878–83. Tanaka Y, et al., EULAR Congress 2016, Poster Number FRI0236. Acknowledgements The authors wish to thank the study investigators. Disclosure of Interest Y. Tanaka Grant/research support from: Mitsubishi-Tanabe, Takeda, Daiichi-Sankyo, Chugai, Bristol-Myers, MSD, Astellas, Abbvie, Eisai, Speakers bureau: Abbvie, Chugai, Daiichi-Sankyo, Bristol-Myers, Mitsubishi-Tanabe, Astellas, Takeda, Pfizer, Teijin, Asahi-kasei, YL Biologics, Sanofi, Janssen, Eli Lilly, GlaxoSmithKline, T. Takeuchi Grant/research support from: Astellas, Bristol-Myers, Chugai, Daiichi-Sankyo, Eisai, AYUMI, Takeda, Teijin, AbbVie, Asahikasei, Taisho-Toyama, Consultant for: Astra Zeneca, Eli Lilly, Novartis, Mitsubishi-Tanabe, Asahi-Kasei, AbbVie, Daiichi-Sankyo, Bristol-Myers, Nipponkayaku, Janssen, Merck Serono, Takeda, Astellas, Pfizer, Speakers bureau: AbbVie, Bristol-Myers, Chugai, Eisai, Janssen, Mitsubishi-Tanabe, Pfizer, Takeda, Astellas, Daiichi-Sankyo, Celtrion, Nipponkayaku, H. Umehara: None declared, T. Nanki Grant/research support from: Chugai, Eisai, Takeda, Teijin, Eli Lilly, Bristol-Myers, AbbVie, Ono, Novartis, Asahi-Kasei, Consultant for: UCB, Eisai, Chugai, Speakers bureau: Mitsubishi-Tanabe, Chugai, Eisai, Takeda, Astellas, Janssen, Eli Lilly, Ayumi, Pfizer, Ono, AbbVie, N. Yasuda Shareholder of: EISAI, Employee of: EISAI, F. Tago Employee of: EISAI, Y. Kitahara Shareholder of: EISAI, Employee of: EISAI, M. Kawakubo Shareholder of: EISAI, Employee of: EISAI, S. Hojo Employee of: EISAI, T. Kawano Employee of: KAN Research Institute, T. Imai Employee of: KAN Research Institute