Magnetization Vector Rotation Reservoir Computing Operated by Redox Mechanism

Physical reservoir computing is a promising way to develop efficient artificial intelligence using physical devices exhibiting nonlinear dynamics. Although magnetic materials have advantages in miniaturization, the need for a magnetic field and large electric current results in high electric power consumption and a complex device structure. To resolve these issues, we propose a redox-based physical reservoir utilizing the planar Hall effect and anisotropic magnetoresistance, which are phenomena described by different nonlinear functions of the magnetization vector that do not need a magnetic field to be applied. The expressive power of this reservoir based on a compact all-solid-state redox transistor is higher than the previous physical reservoir. The normalized mean square error of the reservoir on a second-order nonlinear equation task was 1.69 × 10-3, which is lower than that of a memristor array (3.13 × 10-3) even though the number of reservoir nodes was fewer than half that of the memristor array.

Few- and single-molecule reservoir computing experimentally demonstrated with surface-enhanced Raman scattering and ion gating

Molecule-based reservoir computing (RC) is promising for achieving low power consumption neuromorphic computing, although the information-processing capability of small numbers of molecules is not clear. Here, we report a few- and single-molecule RC that uses the molecular vibration dynamics in the para-mercaptobenzoic acid (pMBA) detected by surface-enhanced Raman scattering (SERS) with tungsten oxide nanorod/silver nanoparticles. The Raman signals of the pMBA molecules, adsorbed at the SERS active site of the nanorod, were reversibly perturbated by the application of voltage-induced local pH changes near the molecules, and then used to perform time-series analysis tasks. Despite the small number of molecules used, our system achieved good performance, including >95% accuracy in various nonlinear waveform transformations, 94.3% accuracy in solving a second-order nonlinear dynamic system, and a prediction error of 25.0 milligrams per deciliter in a 15-minute-ahead blood glucose level prediction. Our work provides a concept of few-molecular computing with practical computation capabilities.

Redox-based ion-gating reservoir consisting of (104) oriented LiCoO2 film, assisted by physical masking

Reservoir computing (RC) is a machine learning framework suitable for processing time series data, and is a computationally inexpensive and fast learning model. A physical reservoir is a hardware implementation of RC using a physical system, which is expected to become the social infrastructure of a data society that needs to process vast amounts of information. Ion-gating reservoirs (IGR) are compact and suitable for integration with various physical reservoirs, but the prediction accuracy and operating speed of redox-IGRs using WO3 as the channel are not sufficient due to irreversible Li+ trapping in the WO3 matrix during operation. Here, in order to enhance the computation performance of redox-IGRs, we developed a redox-based IGR using a (104) oriented LiCoO2 thin film with high electronic and ionic conductivity as a trap-free channel material. The subject IGR utilizes resistance change that is due to a redox reaction (LiCoO2 ⟺ Li1-xCoO2 + xLi+ + xe-) with the insertion and desertion of Li+. The prediction error in the subject IGR was reduced by 72% and the operation speed was increased by 4 times compared to the previously reported WO3, which changes are due to the nonlinear and reversible electrical response of LiCoO2 and the high dimensionality enhanced by a newly developed physical masking technique. This study has demonstrated the possibility of developing high-performance IGRs by utilizing materials with stronger nonlinearity and by increasing output dimensionality.

Effects of Mg Doping to a LiCoO2 Channel on the Synaptic Plasticity of Li Ion-Gated Transistors

Artificial synapses with ideal functionalities are essential in hardware neural networks to allow for energy-efficient analog computing. However, the realization of linear and symmetric weight updates in real synaptic devices has proven challenging and ultimately limits the online training capabilities of neural network systems. Herein, we investigate the effect of Mg doping on a LiCoO2 (LCO) channel in a Li ion-gated synaptic transistor, so as to improve long-term and short-term plasticity. Two transistor structures, based on a lithium phosphorus oxynitride electrolyte, were examined by using undoped LCO and Mg-doped LCO as the channel material between the source and drain electrodes. It was found that Mg doping increased the initial channel conductance by 3 orders of magnitude, which is probably due to the substitution of Co3+ by Mg2+ and the compensation of hole creation. It was further found that the doped channel transistor showed good retention characteristics and better linearity of long-term potentiation and depression when voltage pulses were applied to the gate electrode. The improved retention and linearity are attributed to an extended range of the insulator-to-conductor transition by Mg doping and Li-ion extraction/insertion cooperated in the LCO channel. Using the obtained synaptic weight update, artificial neural network simulations demonstrated that the doped channel transistor shows an image recognition accuracy of ∼80% for handwritten digits, which is higher than ∼65% exhibited by the undoped channel transistor. Mg doping also improved short-term plasticity such as paired-pulse facilitation/depression and Hebbian spike timing-dependent plasticity. These results indicate that elemental doping to the channel of Li ion-gated synaptic transistors could be a useful procedure for realizing robust neuromorphic systems based on analog computing.

Proton-Gated Synaptic Transistors, Based on an Electron-Beam Patterned Nafion Electrolyte

Neuromorphic processors using artificial neural networks are the center of attention for energy-efficient analog computing. Artificial synapses act as building blocks in such neural networks for parallel information processing and data storage. Herein we describe the fabrication of a proton-gated synaptic transistor using a Nafion electrolyte thin film, which is patterned by electron-beam lithography (EBL). The device has an active channel of indium-zinc-oxide (IZO) between the source and drain electrodes, which shows Ohmic behavior with a conductance level on the order of 100 μS. Under voltage applications to the gate electrode, the channel conductance is changed due to the injection and extraction of protons between the IZO channel and the Nafion electrolyte, emulating various synaptic functions with short-term and long-term plasticity. When positive (negative) gate voltage pulses are consecutively applied, the device exhibits long-term potentiation (depression) at the same number of steps as the number of input pulses. Based on these characteristics, an artificial neural network using this transistor shows ∼84% image recognition accuracy for handwritten digits. The subject transistor also successfully mimics paired-pulse facilitation and depression, Hebbian spike-timing-dependent plasticity, and Pavlovian associative learning followed by extinction activities. Finally, dynamical pattern image memorization is demonstrated in a 5 × 5 array of these synaptic transistors. The results indicate that EBL patternable Nafion electrolytes have great potential for use in the fabrication and circuit-level integration of synaptic devices for neuromorphic computing applications.

Nitrogen Plasma Enhanced Low Temperature Atomic Layer Deposition of Magnesium Phosphorus Oxynitride (MgPON) Solid-State Electrolytes

Solid-state batteries (SSBs) that use solid electrolytes instead of flammable liquid electrolytes have the potential to generate higher specific capacity and offer better safety. Magnesium (Mg) based SSBs with Mg metal anodes are considered to be one of the most promising energy storage candidates, because it gives high theoretical volumetric capacities of 3830 mAh cm^-3 . Here, we demonstrate an atomic layer deposition (ALD) process with a double nitrogen plasma process that successfully produces nitrogen-incorporated magnesium phosphorus oxynitride (MgPON) solid-state electrolyte (SSE) thin films at a low deposition temperature of 125 °C. The ALD MgPON SSEs exhibit an ionic conductivity of 0.36 and 1.2 μS cm^-1 at 450 and 500 °C, respectively. The proposed ALD strategy shows the ability of conformal deposition nitrogen-doped SSEs on pattered substrates and is attractive for using nitride ion-conducing films as protective or wetting interlayers in solid-state Mg and Li batteries.

Edge-of-chaos learning achieved by ion-electron-coupled dynamics in an ion-gating reservoir

Physical reservoir computing has recently been attracting attention for its ability to substantially reduce the computational resources required to process time series data. However, the physical reservoirs that have been reported to date have had insufficient computational capacity, and most of them have a large volume, which makes their practical application difficult. Here, we describe the development of a Li⁺ electrolyte-based ion-gating reservoir (IGR), with ion-electron-coupled dynamics, for use in high-performance physical reservoir computing. A variety of synaptic responses were obtained in response to past experience, which were stored as transient charge density patterns in an electric double layer, at the Li⁺ electrolyte/diamond interface. Performance for a second-order nonlinear dynamical equation task is one order of magnitude higher than memristor-based reservoirs. The edge-of-chaos state of the IGR enabled the best computational capacity. The IGR described here opens the way for high-performance and integrated neural network devices.

Quantum Conductance in Memristive Devices: Fundamentals, Developments, and Applications

Quantum effects in novel functional materials and new device concepts represent a potential breakthrough for the development of new information processing technologies based on quantum phenomena. Among the emerging technologies, memristive elements that exhibit resistive switching, which relies on the electrochemical formation/rupture of conductive nanofilaments, exhibit quantum conductance effects at room temperature. Despite the underlying resistive switching mechanism having been exploited for the realization of next-generation memories and neuromorphic computing architectures, the potentialities of quantum effects in memristive devices are still rather unexplored. Here, a comprehensive review on memristive quantum devices, where quantum conductance effects can be observed by coupling ionics with electronics, is presented. Fundamental electrochemical and physicochemical phenomena underlying device functionalities are introduced, together with fundamentals of electronic ballistic conduction transport in nanofilaments. Quantum conductance effects including quantum mode splitting, stability, and random telegraph noise are analyzed, reporting experimental techniques and challenges of nanoscale metrology for the characterization of memristive phenomena. Finally, potential applications and future perspectives are envisioned, discussing how memristive devices with controllable atomic-sized conductive filaments can represent not only suitable platforms for the investigation of quantum phenomena but also promising building blocks for the realization of integrated quantum systems working in air at room temperature.

A floating gate negative capacitance MoS2 phototransistor with high photosensitivity

Monolayer MoS₂ exhibits interesting optoelectronic properties that have been utilized in applications such as photodetectors and light emitting diodes. For image sensing applications, improving the light sensitivity relies on achieving a low dark current that enables the detection weak light signals. Although previous reports on improving the detectivity have been explored with heterostructures and pn junction devices, some of these approaches lack CMOS compatibility processing and sufficient low dark current suppression. Steep slope transistors that overcome the Boltzmann tyranny can further enhance the performance in photodetectors by providing efficient extraction of photogenerated charges. Here, we report a monolayer MoS₂ floating gate negative capacitance phototransistor with the integration of a hafnium-zirconium oxide ferroelectric capacitor. In this study, a SS_min of 30 mV dec^-1, very low dark currents of 10^-13-10^-14 A, and a high detectivity of 7.2 × 10¹⁵ cm Hz^1/2 W^-1 were achieved under weak light illumination due to an enhancement in the photogating effect. In addition, its potential as an optical memory and as an optical synapse with excellent long-term potentiation characteristics in an artificial neural network was also explored. Overall, this device structure offers high photosensitivity to weak light signals for future low-powered optoelectronic applications.

Effects of Oxygen Partial Pressure and Substrate Temperature on the Structure and Morphology of Sc and Y Co-Doped ZrO2 Solid Electrolyte Thin Films Prepared via Pulsed Laser Deposition

Scandium (Sc) and yttrium (Y) co-doped ZrO₂ (ScYSZ) thin films were prepared on a SiO₂-Si substrate via pulsed laser deposition (PLD) method. In order to obtain good quality thin films with the desired microstructure, various oxygen partial pressures (PO2) from 0.01 Pa to 10 Pa and substrate temperatures (T_s) from 25 °C to 800 °C were investigated. X-ray diffraction (XRD) patterns results showed that amorphous ScYSZ thin films were formed at room substrate temperature while cubic polycrystalline thin films were obtained at higher substrate temperatures (T_s = 200 °C, 400 °C, 600 °C, 800 °C). Raman spectra revealed a distinct Raman shift at around 600 cm⁻¹ supporting a cubic phase. However, a transition from cubic to tetragonal phase can be observed with increasing oxygen partial pressure. Photoemission spectroscopy (PES) spectra suggested supporting analysis that more oxygen vacancies in the lattice can be observed for samples deposited at lower oxygen partial pressures resulting in a cubic structure with higher dopant cation binding energies as compared to the tetragonal structure observed at higher oxygen partial pressure. On the other hand, dense morphologies can be obtained at lower  PO2 (0.01 Pa and 0.1 Pa) while more porous morphologies can be obtained at higher PO2 (1.0 Pa and 10 Pa).

Neuromorphic System for Edge Information Encoding: Emulating Retinal Center-Surround Antagonism by Li-Ion-Mediated Highly Interactive Devices

Center-surround antagonism, a key mechanism in the retina, contributes to the encoding of edge contrast rather than of the overall information on a visual image. Here, a neuromorphic system consisting of multiple ionic devices is built, where each device has a lithium cobalt oxide channel arranged on a common lithium phosphorus oxynitride electrolyte. Because of the migration of Li ions between the channels through the electrolyte, the devices are highly interactive, as is seen with retinal neurons. On the basis of the excitation of single devices and device-to-device inhibition, the system successfully emulates the antagonistic center-surround receptive field and the Mach band effect in which perceived contrast is enhanced at the edges between dark and bright regions. Furthermore, a two-dimensional array system is simulated to implement edge detection for real images. This scheme enables computer vision tasks with simple and effective operations, owing to the intrinsic properties of the materials employed.

The electric double layer effect and its strong suppression at Li+ solid electrolyte/hydrogenated diamond interfaces

The electric double layer (EDL) effect at solid electrolyte/electrode interfaces has been a key topic in many energy and nanoelectronics applications (e.g., all-solid-state Li⁺ batteries and memristors). However, its characterization remains difficult in comparison with liquid electrolytes. Herein, we use a novel method to show that the EDL effect, and its suppression at solid electrolyte/electronic material interfaces, can be characterized on the basis of the electric conduction characteristics of hydrogenated diamond(H-diamond)-based EDL transistors (EDLTs). Whereas H-diamond-based EDLT with a Li-Si-Zr-O Li⁺ solid electrolyte showed EDL-induced hole density modulation over a range of up to three orders of magnitude, EDLT with a Li-La-Ti-O (LLTO) Li⁺ solid electrolyte showed negligible enhancement, which indicates strong suppression of the EDL effect. Such suppression is attributed to charge neutralization in the LLTO, which is due to variation in the valence state of the Ti ions present. The method described is useful for quantitatively evaluating the EDL effect in various solid electrolytes.

AB0233 REASONS AND RISK FACTOR FOR DISCONTINUATION OF BIOLOGIC AGENTS FOR RHEUMATOID ARTHRITIS PATIENTS IN LONG-TERM OBSERVATION

Background:

Rheumatoid arthritis (RA) patients who failed a first biologic agent due to any reasons have the option of switching to a second one along with the strategy of biologic agent treatment. Patients go over switching to the next one at failing their biologic agent. On the other hand, there are some patients who discontinue any biologic agent treatment due to various reasons such as tolerability concern, complications, economic issue, remission and so on1 2. The impact of this concern has been less studied.

Objectives:

The objective of this study was to investigate the reasons and the risk factors for discontinuation any biologic agent in RA patients.

Methods:

To Include patients who are observed long-term, patients who underwent biologic agent treatment between 2003 and 2007 at Nagoya University Hospital and 12 other institutes (Tsurumai Biologics Communication Study Group) were enrolled. 570 patients who were confirmed continuation or discontinuation of biologic agent treatment were enrolled. The last observation was September 2017. We analyzed the retention rate of biologic agent treatment and the reasons for discontinuation. To identify the risks for discontinuation, baseline demographics were compared between the continuing group and the disc continuing group using cox hazard regression analysis.

Results:

In total 570 patients, the average duration of treatment with biologics was 6.6±3.3 (years) and total patient-year was 3739 in this study. 458 patients were administered biologics continuously, 112 patients were withdrawn. Table 1 showed the demographic data in total patients. The retention rate was 96.0% (discontinuation n=23) at least 1 year from starting biologics treatment, 92.6% (n=42) at 3 years, 88.2% (n=67) at 5 years, 84.4% (n=89) at 7 years, 81.1% (n=108) at 10 years. In 112 patients who discontinued, the reasons were adverse events in 74 patients, lack of effectiveness in 11 patients, others in 27 patients. Comparison of incidence for discontinuation using cumulative hazard function, the reason of adverse events was significantly higher than others reasons (Figure 1). To identify the risks of discontinuation, we analyzed by multivariable Cox proportional hazard modeling in patients who discontinued treatment due to adverse events, the risk factors (hazard ratio: HR, confidence interval: CI) were over 3 of Steinblocker class (HR 1.85 [1.02-2.04]), age (HR:1.07 [1.04-1.10]) and Non-concomitant with methotrexate (HR 1.90 [1.08-3.33]) (Figure 2).

Table 1.Age (years)56.1 ± 13.4Gender n (% male)110 (19%) n (% female)460 (81%)Disease duration (years)11.1 ± 9.8stage 1,2104 (19%) 3,4455 (81%)class 1,2336 (60%) 3,4225 (40%)Methotrexate use, no (%)400 (70%)Glucocorticoid use, no (%)262 (47%)Rheumatoid Factor, no (%)287 (65%)anti CCP antibody, no (%)137 (87%)

Conclusion:

The most common reason for discontinuation was adverse events in long term observation. The risk factors for discontinuation were class, age, and non-concomitant MTX. These results suggested that comorbidity has a significant impact on continuation rates because there are some reasons of non-concomitant MTX in addition to relate with age and the activities of daily living.

References:

[1]Marussa B, et al. j.clin thera. 2011; 33(7): 901-913

[2]Alejandro S, et al. Rheumatol. 2016; 55(3): 523-34

Disclosure of Interests:

KENYA TERABE: None declared, Nobunori Takahashi Speakers bureau: AbbVie, Asahi Kasei, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Eli Lilly, Janssen, Mitsubishi Tanabe, Ono, Pfizer, Takeda, and UCB Japan, Shuji Asai Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Janssen, Takeda, and UCB Japan, Yuji Hirano Speakers bureau: Tanabe-Mitsubishi, Pfizer, Eisai, Abbie, Chugai, Bristol-Meyers, Jansen, Astellas, UCB, Eli-Lilly, Asahikasei, Daiichi-Sankyo, Amgen, Yasuhide Kanayama: None declared, Toshihisa Kojima Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eli Lilly, Janssen, Mitsubishi Tanabe, Pfizer, and Takeda, Consultant of: AbbVie, Grant/research support from: Chugai, Eli Lilly, Astellas, Abbvie, and Novartis

Room-Temperature Manipulation of Magnetization Angle, Achieved with an All-Solid-State Redox Device

An all-solid-state redox device, composed of magnetite (Fe₃O₄) thin film and Li⁺ conducting electrolyte thin film, was fabricated for the manipulation of a magnetization angle at room temperature (RT). This is a key technology for the creation of efficient spintronics devices, but has not yet been achieved at RT by other carrier doping methods. Variations in magnetization angle and magnetic stability were precisely tracked through the use of planar Hall measurements at RT. The magnetization angle was reversibly manipulated at 10° by maintaining magnetic stability. Meanwhile, the manipulatable angle reached 56°, although the manipulation became irreversible when the magnetic stability was reduced. This large manipulation of magnetic angle was achieved through tuning of the 3d electron number and modulation of the internal strain in the Fe₃O₄ due to the insertion of high-density Li⁺ (approximately 10²¹ cm^-3). This RT manipulation is applicable to highly integrated spintronics devices due to its simple structure and low electric power consumption.

AB0353 COMPARATIVE STUDY OF PATIENT BACKGROUND AND TREATMENT OUTCOME BY BARICITINIB DOSE UNDER REAL CLINICAL CONDITIONS

Background:

Balicitinib (BAR) is one of the Janus kinase (JAK) inhibitors, which mainly inhibits JAK1 and JAK2 and has an anti-inflammatory effect on rheumatoid arthritis(RA). In Japan, it is necessary to use different doses of BAR depending on the RA patient’s estimated glomerular filtration rate (eGFR). The RA-BEACOM and RA-BUILD trials reported the treatment effects by BAR dose at 24 weeks and concluded that there was no difference in DAS(disease activity score)28CRP between BAR 2mg and 4mg. The patient background treated in these double-blind RCTs is uniform even at different BAR doses.There is uncertainty about the difference in the therapeutic effects of BAR dose under the real clinical setting where the patient background differs from that of the trial patients.

Objectives:

To compare patient backgrounds and treatment outcome by Baricitinib dose under real clinical setting.

Methods:

113 RA patients taking BAR who were registered in the Nagoya University Orthopedic Surgery Multicenter Study (TBCR) were included in this study. Patient characteristics (such as age, illness duration, combined anti-rheumatic drugs, eGFR) and DAS28CRP, clinical and simplified disease activity index(CDAI, SDAI respectively) up to 24 weeks were compared between BAR 2mg and 4mg groups. The continuation rates, including the discontinuation due to ineffectiveness and adverse events (AEs), were also compared between the two groups. For these comparisons, Student’s t-test and Pearson’s chi-square test, Kaplan-Meier survival curve were used. Missing data due to discontinuation of BAR was complemented by LOCF method and analyzed statistically. The significance level was set to less than 0.05.

Results:

There were 39 subjects (8 males and 31 females) in BAR2mg group and 74 patients (17 males and 57 females) in BAR4mg group. There was a significant difference in mean age (73.5 vs. 62.3 years old,p<0.001), average eGFR (65.1vs 84.8ml / min / 1.73m2,p<0.001), methotrexete(MTX) use rate (28 vs 58%,p<0.01), average MTX dose (3.0 vs 5.5mg,p<0.01),glucocorticoid(GC) use rate(51.3 vs 33.8%,p<0.01) between the two groups(Table). DAS28CRP improved from week 0 (3.2 vs 3.5) to week 24 (2.5 vs 2.4), and no significant difference was observed between the two groups at each time point (Fig.1-A). The same was true for CDAI and SDAI(Fig.1-B,-C). The rate of DAS28CRP remission and low disease activity was not significantly different at 24 weeks (0.64 vs. 0.69, Fig.1-D). The same was true for CDAI and SDAI(Fig.1-E,-F). Kaplan-Meier analysis showed that there was no difference in discontinuation rate due to ineffectiveness in the two groups. The same was true for the discontinuation rate due to AEs (Figure 2-B,-C). The total continuation rate including discontinuation due to ineffectiveness and AEs was significantly lower in BAR2mg group (0.691 vs 0.843,p<0.05, Fig.2-A).

Conclusion:

BAR2mg group under real clinical setting was older and had lower eGFR than BAR4mg group. Although the treatment effect for 24 weeks was similar, safety management was considered more important because the discontinuation rate due to AEs tended to be higher in BAR2mg group.

References:

[1]Taylor PC, (2017) The New England journal of medicine. 376(7), 652.

[2]Takeuchi T, Ann Rheum Dis 2019;78:171–178.

[3]Keystone EC, Ann Rheum Dis 2015;74:333–340

Table 1.

ITT outcomes at week 13

BAR2mg (n=39)BAR4mg (n=74)pvalueAge, years old73.5±9.762.3±12.6<0.001Female31(79)57(77)0.767Disease duration, year13.7±11.314.2±15.40.857Stage(1/2/3/4)6/17/8/815/24/14/210.473ACPA >4.5U/ml29(74.4)59(79.7)0.629eGFR, ml/min/1.73m265.1±27.784.8±23.2<0.001MTX dose, mg/week3.03±4.835.54±5.480.018MTX use11(28.2)41(55.4)0.003GC dose, mg/day1.91±2.361.32±2.200.191GC use20(51.3)25(33.8)0.007DAS28CRP3.42±1.043.52±13.00.689CDAI12.6±7.615.1±10.90.222SDAI14.7±9.716.2±11.40.279

Values are the mean±SD or the number (%).

Disclosure of Interests:

Tsuyoshi Nishiume: None declared, Nobunori Takahashi Speakers bureau: AbbVie, Asahi Kasei, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Eli Lilly, Janssen, Mitsubishi Tanabe, Ono, Pfizer, Takeda, and UCB Japan, Toshihisa Kojima Grant/research support from: Chugai, Eli Lilly, Astellas, Abbvie, and Novartis, Consultant of: AbbVie, Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eli Lilly, Janssen, Mitsubishi Tanabe, Pfizer, and Takeda, Shuji Asai Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Janssen, Takeda, and UCB Japan, Kenya Terabe: None declared, Naoki Ishiguro Grant/research support from: AbbVie, Asahi Kasei, Astellas, Chugai, Daiichi-Sankyo, Eisai, Kaken, Mitsubishi Tanabe, Otsuka, Pfizer, Takeda, and Zimmer Biomet, Consultant of: Ono, Speakers bureau: Astellas, Bristol-Myers Squibb, Daiichi-Sankyo, Eli Lilly, Pfizer, and Taisho Toyama

FRI0107 EFFECTIVENESS OF ABATACEPT ON CLINICAL DISEASE ACTIVITY AND RADIOGRAPHIC PROGRESSION IN RHEUMATOID ARTHRITIS PATIENTS IN DAILY CLINICAL PRACTICE IN JAPAN: COMPARISONS ACCORDING TO ACPA STATUS

Background:

The clinical effectiveness of abatacept (ABA) in rheumatoid arthritis (RA) patients has been reported to be higher when the patients’ anti-cyclic citrullinated peptide antibody (ACPA) status is positive. The report from the ORA registry demonstrated that the ACPA positivity was associated with a better response to ABA [1]. In a sub-analysis of the AMPLE trial, patients with very high ACPA titers who were treated with ABA had a statistically significant response compared to patients with lower titers [2]. However, these studies did not demonstrate the data regarding the structural progression.

Objectives:

This study aimed to evaluate the effectiveness of ABA on the clinical disease activity as well as the radiographic progression in patients with RA in the clinical settings.

Methods:

All eligible patients were registered in the TBCR, a Japanese multicenter registry system for RA patients treated with biologics [3]. The present study included 553 consecutive patients whose ACPA data were obtained, treated with ABA and observed for longer than 52 weeks. We primarily compared the status of disease activity (SDAI) and radiographic progression (van der Heijde modified total Sharp score: mTSS) between ACPA-positive [ACPA (+)] and ACPA-negative [ACPA (-)] RA patients. The ACPA positive was defined as ≥13.5 U/ml of anti-CCP antibody.

Results:

Number of cases was 446/ 107 [ACPA (+)/ ACPA (-)], respectively. Baseline characteristics between groups were quite similar; mean age was 68.0/ 67.3 years, rate of methotrexate (MTX) use rate was 41.2/ 50.0%, rate of bio-naive was 28.0/ 31.8%, and mean SDAI score was 22.2/ 20.8. Significant difference was observed in mean change in SDAI score from baseline to 52 weeks between the ACPA (+) and ACPA (-) group (-13.4 vs -9.9, p = 0.027) (Figure 1A). Proportion of patents that achieved low disease activity (LDA; SDAI ≤11) at 52 weeks was significantly higher in the ACPA (+) group compared to the ACPA (-) group (72.1 vs 56.0%, p < 0.01) (Figure 1B). In univariate and multivariate logistic regression analysis, ACPA positivity was an independent predictor for achievement of LDA at 52 weeks (Table). There observed no significant difference between ACPA (+) and ACPA (-) group in the proportion of patients that achieved structural remission (ΔmTSS ≤0.5) at 52 weeks (66.2 vs 62.1%) (Figure 2A) as well as mean change in mTSS (1.66 vs 1.17), erosion score (0.60 vs 0.53), and joint narrowing (JSN) score (1.06 vs 0.64) (Figure 2B).

Table.UnivariateMultivariateVariablesOR (95%CI)p-valueadjusted OR (95%CI)p-valueAge0.99 (0.98-1.01)0.4391.00 (0.97-1.02)0.749male (vs female)1.12 (0.70-1.80)0.6340.79 (0.40-1.58)0.511disease duration0.99 (0.97-1.00)0.0530.99 (0.97-1.01)0.468Biologics-naïve1.23 (0.81-1.85)0.3351.18 (0.67-2.08)0.575Concomitant MTX use1.12 (0.75-1.69)0.5851.14 (0.66-1.95)0.649Concomitant PSL use0.82 (0.55-1.23)0.3290.97 (0.58-1.64)0.923SDAI @baseline0.96 (0.94-0.97)<0.0010.96 (0.94-0.98)<0.001mHAQ @baseline0.50 (0.36-0.69)<0.0010.57 (0.38-0.86)0.008ACPA positive2.03 (1.29-3.17)0.0022.61 (1.36-5.00)0.004Bold italic, p<0.05

Conclusion:

Consistent with previous reports, the ACPA-positive group demonstrated significantly higher LDA achievement rate at 52 weeks and indeed the ACPA positivity was significantly associated with LDA achievement in multivariate analysis. However, the ACPA-negative group demonstrated quite similar transition of SDAI score and LDA achievement rate except at 52 weeks compared with the ACPA-positive group. Additionally, there was no significant difference in the structural progression at 52 weeks between the groups. ABA treatment may be considered not only in the ACPA-positive RA patients but also in the ACPA-negative patients in the clinical practice.

References:

[1]Gottenberg JE, et al. Ann Rheum Dis. 2012;71:1815.

[2]Sokolove J, et al. Ann Rheum Dis. 2016;75:709.

[3]Takahashi N, et al. Rheumatology (Oxford). 2015;54:854.

Disclosure of Interests:

Nobunori Takahashi Speakers bureau: AbbVie, Asahi Kasei, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Eli Lilly, Janssen, Mitsubishi Tanabe, Ono, Pfizer, Takeda, and UCB Japan, Toshihisa Kojima Grant/research support from: Chugai, Eli Lilly, Astellas, Abbvie, and Novartis, Consultant of: AbbVie, Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eli Lilly, Janssen, Mitsubishi Tanabe, Pfizer, and Takeda, Shuji Asai Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Janssen, Takeda, and UCB Japan, Kenya Terabe: None declared, Naoki Ishiguro Grant/research support from: AbbVie, Asahi Kasei, Astellas, Chugai, Daiichi-Sankyo, Eisai, Kaken, Mitsubishi Tanabe, Otsuka, Pfizer, Takeda, and Zimmer Biomet, Consultant of: Ono, Speakers bureau: Astellas, Bristol-Myers Squibb, Daiichi-Sankyo, Eli Lilly, Pfizer, and Taisho Toyama

AB0178 PERIARTICULAR OSTEOPHYTE FORMATION PROTECTS AGAINST TOTAL KNEE ARTHROPLASTY IN RHEUMATOID ARTHRITIS PATIENTS WITH ADVANCED JOINT DAMAGE

Background:

New medications including biologics and aggressive treatment strategies can halt the inflammatory and destructive disease processes in patients with rheumatoid arthritis (RA), and in some cases repair damaged joints. In the process of damaged joint repair, periarticular osteophyte formation might be detected radiographically (1). However, little is known about the clinical and functional role of osteophyte formation in RA joints. Total joint arthroplasty, a common procedure for treating damaged large joints, can serve as a surrogate for the long-term outcome of large joint destruction in patients with RA.

Objectives:

To determine the influence of periarticular osteophyte formation on the incidence of total knee arthroplasty (TKA) in patients with RA.

Methods:

This retrospective longitudinal study used data from a registry of patients with RA starting biologics. A flow chart summarizing the study design is shown in Figure 1. A total of 130 symptomatic (tender and/or swollen) knee joints in 80 patients were studied with a median follow-up of 12 years. All data were analyzed using the knee joint as the statistical unit of analysis. The cumulative incidences of TKA were estimated using Kaplan-Meier curves, and compared according to the presence or absence of osteophyte on plain anteroposterior radiograph [osteophyte (+/-)] and the extent of advanced joint damage as defined by Larsen’s grading system (0-II vs. III-V).

Results:

Baseline characteristics of all subjects included in this study are shown in Table 1. A total of 42 knees underwent TKA during the follow-up period. There was no significant difference in the cumulative incidence of TKA between the osteophyte (+) and osteophyte (-) groups (31% vs. 34% at 10 years, P=0.718) (Fig. 2A). The cumulative incidence of TKA was significantly higher for the Larsen grade III-V group compared to the Larsen grade 0-II group (56% vs. 10% at 10 years, P<0.001) (Fig. 2B). While no significant difference was observed in the cumulative incidence of TKA between the osteophyte (+) and osteophyte (-) groups in the Larsen grade 0-II group (9% vs. 10% at 10 years, P=0.774) (Fig. 2C), the cumulative incidence of TKA was significantly lower for the osteophyte (+) group compared to the osteophyte (-) group in the Larsen grade III-V group (38% vs. 74% at 10 years, P=0.010) (Fig. 2D). Multivariate analysis using Cox proportional hazards models revealed that older age [hazard ratio (HR): 1.04 per 1 year, 95% confidence interval (CI): 1.01-1.08] and osteophyte formation (HR: 0.39, 95% CI: 0.19-0.79) independently predicted TKA in the Larsen grade III-V group, whereas none of the assessed variables predicted TKA in the Larsen grade 0-II group.

Table 1.

Baseline characteristics by presence or absence of osteophyte formation

TotalOsteophyte (+)Osteophyte (-)Characteristicsn = 130n = 44n = 86PvalueAge, years57(41-63)59(52-65)56(39-63)0.051Sex, female, n (%)108(83)40(91)68(80)0.137Body mass index21.3(19.0-23.8)21.3(18.9-24.4)21.2(19.0-23.7)0.744Disease duration, years8(3-12)9(5-18)7(3-11)0.007Larsen grade, n (%)<0.001Grade 0-II66(51)11(25)55(64)Grade III-V64(59)33(75)31(36)Osteophyte formation, n (%)44(34)---RF or ACPA positive, n (%)85(83)35(90)50(78)0.183CRP, mg/dl3.2(1.5-4.9)2.9(1.0-4.1)3.4(1.8-5.2)0.172First biologic agent, n (%)1.000Infliximab57(44)19(43)38(44)Etanercept73(56)25(57)48(56)Use of methotrexate, n (%)98(75)33(75)65(76)1.000Methotrexate dose, mg/week*8(6-10)8(6-9)8(6-10)0.104Use of glucocorticoids, n (%)79(61)22(50)57(66)0.088Glucocorticoid dose, mg/day*†5.0(5.0-7.5)5.0(5.0-5.0)5.0(5.0-7.8)0.204

Data are presented as median (interquartile range) or number of subjects (percentages). *Median among subjects receiving the drug. †Prednisolone equivalent (mg/day).

Conclusion:

Osteophyte formation reduces the incidence of TKA in patients with RA who have advanced joint damage.

References:

[1]Rau R. Clin Exp Rheumatol 2006;24:S-41-4.

Disclosure of Interests:

Shuji Asai Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Janssen, Takeda, and UCB Japan, Nobunori Takahashi Speakers bureau: AbbVie, Asahi Kasei, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Eli Lilly, Janssen, Mitsubishi Tanabe, Ono, Pfizer, Takeda, and UCB Japan, KENYA TERABE: None declared, Toshihisa Kojima Grant/research support from: Chugai, Eli Lilly, Astellas, Abbvie, and Novartis, Consultant of: AbbVie, Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eli Lilly, Janssen, Mitsubishi Tanabe, Pfizer, and Takeda, Naoki Ishiguro Grant/research support from: AbbVie, Asahi Kasei, Astellas, Chugai, Daiichi-Sankyo, Eisai, Kaken, Mitsubishi Tanabe, Otsuka, Pfizer, Takeda, and Zimmer Biomet, Consultant of: Ono, Speakers bureau: Astellas, Bristol-Myers Squibb, Daiichi-Sankyo, Eli Lilly, Pfizer, and Taisho Toyama

THU0182 THE EFFECTIVENESS OF BIOLOGICAL AGENTS CONCOMITANT WITH TACROLIMUS IN RHEUMATOID ARTHRITIS

Background:

In Japan, oral tacrolimus (TAC) was approved for the treatment of RA in 2005 and the improvement of symptoms thorough the use concomitant with disease modifying antirheumatic drugs (DMARDs), including MTX has been reported1 2. On the other hand, the efficacy and tolerance of biological agents therapy concomitant with TAC are unknown.

Objectives:

The objective of this study was to investigate the efficacy and tolerance of biological agents concomitant with TAC in Japanese patients with RA using retention rate analysis.

Methods:

Total patients (n=2860) who underwent 5 biological agents (etanercept: ETN, adalimumab: ADA, golimumab:GLM, tocilizumab: TCZ, abatacept: ABT) treatment between 2003 and 2017 at Nagoya University Hospital and 12 other institutes (Tsurumai Biologics Communication Study Group) were enrolled3. In each biologics analysis, patients were divided into three groups: (1) concomitant only MTX (MTX group) (2) concomitant only TAC (TAC group) (3) others (others group). In TAC or MTX group, these drugs were only ones which concomitant with biologics. Kaplan-Meier analysis was used to estimate retention rate in each biologics group. To estimate the tolerance of concomitant biologics with TAC, cumulative hazard function in adverse events rate was performed in each biologics group. In both analyses, hazard ratios (HR) were assessed by Cox proportional hazards modeling adjusted for age, sex, disease duration and previously used biologics.

Results:

In total 2860 patients, 142 patients (5.0%) administered each biologics concomitant with TAC (ETN: n=47, ADA: n=10 GLM: n=14, TCZ: n=27, ABT: n=49). Baseline characteristics of 142 patients were shown in table 1. Average dosages of TAC at starting were ETN: 2.2±0.7mg ADA: 2.4±1.0mg GLM: 1.9±1.0mg TCZ: 1.7±0.9mg ABT: 1.9±0.9mg. With comparison of retention rate between 3 groups in each biologics under analysis of cox proportional hazard modeling, in ETN and ABT analysis, the retention rate of TAC group was higher than others group (table 2, figure 1). Comparison of incidence of adverse event between 3 group using cumulative hazard function and cox proportional hazard modeling in ETN and ABT analysis. In ETN analysis, incident rate of other group was higher than TAC group. In ABT analysis, there was no significant difference between 3 gruops (figure 2).

Table 1.Baseline characteristic (n=142)age (years)63 ± 3gendermale33 (23%)female109 (77%)disease duration (years)12.0 ± 7.8stage1,234 (24%)3,4108 (76%)class1,299 (70%)3,443 (30%)naïve vs switchnaïve71 (50%)switch71 (50%)corticosteroid use, no (%)+98 (75%)-32 (25%)corticosteroid dose (mg)5.6 ± 3.2DAS28-ESR4.71 ± 1.55Table 2.HR (95%CI)/p-valuen (MTX/TAC/others)ETNADAGLMTCZABT(774/ 47/ 486)(339/ 10/ 135)(156/ 14/ 61)(272/ 27/ 207)(213/ 49/ 178)TAC vs others0.27 (0.16-0.45)<0.0010.9 (0.37-2.20)ns0.46 (0.13-1.63)ns0.55 (0.24-1.31)ns0.51 (0.26-0.97)<0.05TAC vs MTX0.65 (0.38-1.08)ns1.42 (0.61-3.31)ns0.83 (0.24-2.87)ns0.5 (0.21-1.17)ns0.74 (0.39-1.42)nsMTX vs others0.42 (0.35-0.50)<0.0010.9 (0.50-0.88)<0.0010.56 (0.33-0.96)<0.051.01 (0.78-1.57)ns0.68 (0.46-0.99)<0.05

Bold italic: p<0.05CI: confidence interval ns: not significant

Conclusion:

We suspected that, in ETN and ABT treatment, combination therapy with TAC are subsequent options for treatment to RA patients, especially in whom MTX cannot be administration.

References:

[1]Kino T, et al. Antibiot. 1987 Sep 40(9): 1256-65

[2]Kondo H, et al. J Rheumatol. 2004 Feb;31(2):243-51

[3]Kojima T, et al. Mod Rheumatol. 2011 Sep 3.

Disclosure of Interests:

KENYA TERABE: None declared, Nobunori Takahashi Speakers bureau: AbbVie, Asahi Kasei, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Eli Lilly, Janssen, Mitsubishi Tanabe, Ono, Pfizer, Takeda, and UCB Japan, Shuji Asai Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Janssen, Takeda, and UCB Japan, Atsushi Kaneko Speakers bureau: Abbvie, Asahi-Kasei, Astellas, Bristol-Myers Squibb, Chugai, Eisai, Eli Lily, Mitsubishi-Tanabe, Pfizer, and UCB Japan, Yuji Hirano Speakers bureau: Tanabe-Mitsubishi, Pfizer, Eisai, Abbie, Chugai, Bristol-Meyers, Jansen, Astellas, UCB, Eli-Lilly, Asahikasei, Daiichi-Sankyo, Amgen, Yasuhide Kanayama: None declared, Yuichiro Yabe Speakers bureau: Asahi Kasei, Janssen, and Mitsubishi Tanabe, Toshihisa Kojima Grant/research support from: Chugai, Eli Lilly, Astellas, Abbvie, and Novartis, Consultant of: AbbVie, Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eli Lilly, Janssen, Mitsubishi Tanabe, Pfizer, and Takeda, Naoki Ishiguro Grant/research support from: AbbVie, Asahi Kasei, Astellas, Chugai, Daiichi-Sankyo, Eisai, Kaken, Mitsubishi Tanabe, Otsuka, Pfizer, Takeda, and Zimmer Biomet, Consultant of: Ono, Speakers bureau: Astellas, Bristol-Myers Squibb, Daiichi-Sankyo, Eli Lilly, Pfizer, and Taisho Toyama

FRI0135 PREDICTORS FOR SHORT-TERM CLINICAL EFFECTIVENESS OF BARICITINIB IN RHEUMATOID ARTHRITIS PATIENTS IN ROUTINE CLINICAL PRACTICE: DATA FROM A JAPANESE MULTICENTER REGISTRY

Background:

Baricitinib is considered as a specific JAK1/2 inhibitor. While a number of randomized controlled trials have reported on the clinical efficacy and safety profile of baricitinib in rheumatoid arthritis (RA) patients, clinical data for RA patients in routine clinical practice are scarce.

Objectives:

This study aimed to evaluate the short-term effectiveness and safety profiles of baricitinib and explore factors associated with improved short-term effectiveness in patients with RA in clinical settings.

Methods:

A total of 113 consecutive RA patients who had been treated with baricitinib were registered in the TBCR, a Japanese multicenter registry for RA patients treated with biologics or JAK inhibitors (targeted DMARDs) [3], and followed for at least 24 weeks. Univariate and multivariate logistic regression analysis was used to study predictive factors for achievement of low disease activity (LDA) at 24 weeks.

Results:

Mean age was 66.1 years, mean RA disease duration was 14.0 years, 71.1% had a history of use targeted DMARDs, and 48.3% and 40.0% were receiving concomitant methotrexate (MTX) and oral prednisone, respectively. Mean DAS28-CRP significantly decreased from 3.55 at baseline to 2.32 at 24 weeks (Figure 1A). At 24 weeks, 68.2% and 64.1% of patients achieved LDA and moderate or good response, respectively (Figure 1B). Multivariate logistic regression analysis revealed that no previous targeted DMARD use and lower DAS28-CRP score at baseline were independently associated with achievement of LDA at 24 weeks (Table). While the percent change in DAS28-CRP was similar regardless of whether patients used concomitant MTX (Figure 2A), patietns with previous use of targeted DMARDs (Switch group) showed lower percent improvement in DAS28-CRP compared to targeted DMARDs-naïve patients (Naïve group) (Figure 2B). The overall retention rate for baricitinib was 86.5% at 24 weeks, as estimated by Kaplan-Meier analysis. The discontinuation rate due to adverse events was 6.5% at 24 weeks. In the present study cohort, seven patients developed herpes zoster, with an incidence rate of 8.4 per 100 patient-years. All seven patients were treated with antiviral agents for herpes zoster and restarted baricitinib treatment.

TableUnivariateMultivariatevariablesOR (95%CI)p-valueadjusted OR (95%CI)p-valueMale1.17 (0.43-3.16)0.755Age, <65 years1.46 (0.62-3.44)0.388Disease duration, <10 years1.41 (0.61-3.23)0.419ACPA positive1.56 (0.51-4.80)0.433no previous biological DMARDs4.67 (1.49-14.66)0.00833.4 (2.53-442.62)0.008concomitant MTX0.860 (0.40-2.02)0.789concomitant PSL0.24 (0.10-0.56)0.001DAS28-CRP@baseline0.55 (0.38-0.80)0.0020.28 (0.13-0.62)0.002mHAQ@baseline0.27 (0.09-0.77)0.015Bold italic, p<0.05

Conclusion:

In this study, we demonstrated the short-term clinical effectiveness and safety profile of baricitinib in Japanese RA patients in the ‘real-world’ setting. To the best of our knowledge, this study is the first to report the clinical outcomes of baricitinib in routine clinical practice in Japan. Baricitinib significantly improved disease activity, with an expected safety profile. We observed some interesting features regarding the effectiveness of baricitinib. Baricitinib was significantly more effective when used as a first-line targeted DMARD and may play a key role in the modern treatment strategy for RA, although careful observation is necessary for possible complications and AEs including herpes zoster.

References:

[1]Taylor PC, et al. (2017) The New England journal of medicine. 376(7), 652.

[2]Tanaka Y, et al. (2018) Modern rheumatology. 28(1), 20-9.

[3]Takahashi N, et al. (2014) Rheumatology (Oxford) 2014.

Disclosure of Interests:

Nobunori Takahashi Speakers bureau: AbbVie, Asahi Kasei, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Eli Lilly, Janssen, Mitsubishi Tanabe, Ono, Pfizer, Takeda, and UCB Japan, Toshihisa Kojima Grant/research support from: Chugai, Eli Lilly, Astellas, Abbvie, and Novartis, Consultant of: AbbVie, Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eli Lilly, Janssen, Mitsubishi Tanabe, Pfizer, and Takeda, Shuji Asai Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Janssen, Takeda, and UCB Japan, Kenya Terabe: None declared, Naoki Ishiguro Grant/research support from: AbbVie, Asahi Kasei, Astellas, Chugai, Daiichi-Sankyo, Eisai, Kaken, Mitsubishi Tanabe, Otsuka, Pfizer, Takeda, and Zimmer Biomet, Consultant of: Ono, Speakers bureau: Astellas, Bristol-Myers Squibb, Daiichi-Sankyo, Eli Lilly, Pfizer, and Taisho Toyama

SAT0122 HIGHER DOSES OF METHOTREXATE ASSOCIATED WITH DISCONTINUATION OF ORAL GLUCOCORTICOIDS AFTER INITIATION OF BIOLOGICAL DMARDS: A RETROSPECTIVE OBSERVATIONAL STUDY BASED ON DATA FROM A JAPANESE MULTICENTER REGISTRY STUDY

Background:

Glucocorticoids exert anti-inflammatory effects and are important drugs used to treat rheumatoid arthritis(1). We recommend glucocorticoid discontinuation as soon as possible because glucocorticoid caused several side effects, but many patients continue to take oral glucocorticoids long-term in daily clinical practice. The frequency of use of glucocorticoid has gradually declined, and there are several reports on discontinuation of glucocorticoid due to the initiation of biological disease-modifying antirheumatic drugs (bDMARDs)(2). However, there is no report showing the relation between discontinuation of glucocorticoid and MTX dose.

Objectives:

The present study aimed to explore factors associated with glucocorticoid discontinuation at 52 weeks after initiating bDMARDs.

Methods:

We established the large observational cohort, the Nagoya University orthopedic facility multicenter study (TBCR), and a total of 3119 patients used bDMARD and examined the status of oral glucocorticoid use at 52 weeks after initiating the 1stbDMARD. In predictive analyses, the outcome variable was glucocorticoid discontinuation at 52 weeks after bDMARD initiation. Factors associated with baseline characteristics at bDMARD initiation were assessed with univariate and stepwise forward multivariate logistic regression analyses. This cohort study was not randomized. Propensity score (PS) matching was used to align patient backgrounds to avoid selection bias.

Results:

Subjects were 564 patients administered glucocorticoids and methotrexate (MTX) following initiation of the 1stbDMARD (Figure 1). Mean DAS28-CRP at bDMARD initiation was 4.70 ± 1.16. Percentages of patients with low, moderate, and high disease activity as evaluated by DAS28-CRP at bDMARD initiation were 4.7%, 23.5%, and 71.8%, respectively. By 52 weeks after bDMARD initiation, 164 patients (29.1%) discontinued glucocorticoids. Multivariate analysis identified age (odds ratio (OR), 0.98), MTX dose (OR, 1.11), and glucocorticoid dose (OR, 0.87) as factors independently associated with glucocorticoid discontinuation at the time of bDMARD initiation (Table 1). After adjusting for baseline characteristics using propensity score matching among patient groups administered MTX ≤ 8 mg/week and MTX > 8 mg/week, 105 pairs remained. Among patients administered MTX > 8 mg/week, 41.0% discontinued glucocorticoids. Among those administered MTX ≤ 8 mg/week, 22.9% discontinued glucocorticoids, with a significant difference between the two groups (Figure 2, P=0.007).

Table 1.

Factors associated with baseline characteristics at bDMARD initiation

Continuation(n=400)Discontinuation(n=164)UnivariateOdds ratio (95% CI)MultivariateOdds ratio (95% CI)Age, years58.4 ± 12.954.3 ± 14.30.98 (0.97-0.99)*0.98 (0.97-0.99)*Disease duration, years9.4 ± 9.47.5 ± 8.50.98 (0.95-0.99)*–Female, %80.381.11.06 (0.67-1.68)–DAS28-CRP4.78 ± 1.154.50 ± 1.160.81 (0.69-0.96)*–Seropositivity, %90.086.10.69 (0.38-1.25)–MTX dose, mg/week7.7 ± 2.58.8 ± 3.01.16 (1.09-1.24)*1.11 (1.03-1.21)*Glucocorticoid dose, mg/day4.9 ± 2.14.3 ± 2.10.86 (0.78-0.95)*0.87 (0.78-0.97)*TNF inhibitor use, %88.885.40.74 (0.43-1.26)-

Data are presented as mean ± standard deviation.

Conclusion:

Data from the TBCR revealed that, from a clinical perspective, glucocorticoid use decreased among RA patients treated with bDMARDs. Higher doses of MTX (> 8 mg/week) at the time of bDMARD initiation were found to be associated with glucocorticoid discontinuation in patients treated with bDMARDs. In addition, we found that aggressive use of MTX was sufficient to fulfill the Treat-to-Target approach, demonstrating that glucocorticoid discontinuation is a viable option.

References:

[1]Smolen JS. Ann Rheum Dis. 2014;73(3):492-509.

[2]Shimizu Y. Mod Rheumatol. 2018;28(3):461-7.

Disclosure of Interests:

Mochihito Suzuki Speakers bureau: Bristol-Myers Squibb, Eisai, and Asahi Kasei, Toshihisa Kojima Grant/research support from: Chugai, Eli Lilly, Astellas, Abbvie, and Novartis, Consultant of: AbbVie, Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eli Lilly, Janssen, Mitsubishi Tanabe, Pfizer, and Takeda, Nobunori Takahashi Speakers bureau: AbbVie, Asahi Kasei, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Eli Lilly, Janssen, Mitsubishi Tanabe, Ono, Pfizer, Takeda, and UCB Japan, Shuji Asai Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Janssen, Takeda, and UCB Japan, Kenya Terabe: None declared, Naoki Ishiguro Grant/research support from: AbbVie, Asahi Kasei, Astellas, Chugai, Daiichi-Sankyo, Eisai, Kaken, Mitsubishi Tanabe, Otsuka, Pfizer, Takeda, and Zimmer Biomet, Consultant of: Ono, Speakers bureau: Astellas, Bristol-Myers Squibb, Daiichi-Sankyo, Eli Lilly, Pfizer, and Taisho Toyama

OP0207 MECHANISM OF CHONDROPROTECTIVE EFFECTS OF 2-DEOXYGLUCOSE

Background:

We recently reported that the inhibitor of hyaluronan (HA) biosynthesis, 4-methylumbelliferone (4-MU) blocked IL-1β activation of MMP13 mRNA and protein expression in human osteoarthritic (OA), bovine as well as bovine or OA cartilage explants [1]. This was a somewhat counterintuitive observation because we have also demonstrated that the overexpression of HAS2 (HAS2-OE) exerted the same chondroprotective effects on human and bovine chondrocytes. Others [2] have reported that HAS2-OE in tumor cells generates a flux in intracellular UDP-sugar pools that resulted in changes in cell metabolism; switching from a dependence on glycolysis to aerobic respiration. HAS2-OE and 4-MU likely also cause dramatic fluxes in intracellular UDP-GlcUA pools. From these results, we hypothesized that the effect of HAS2-OE and 4-MU relate to changing metabolism and the possibility of inhibition of glycolysis induce chondroprotective effect. To determine that, we used the glycolysis inhibitor, 2-Deoxyglucose (2DG) as an alternative agent to change metabolism in chondrocytes.

Objectives:

The objective of this study was to investigate the mechanism of chondroprotective effects of 2DG

Methods:

Bovine and human chondrocyte were stimulated with IL-1β (2ng/ml) in the presence or absence of 4MU (1.0 mM), 2DG (0.2-20 mM). Bovine chondrocytes were tested using Seahorse Flux Analyzer (Agilent Tech) to determine rate changes in medium accumulation of +H protons (indicative of lactic acid accumulation: ECAR) and for O2 consumption (indicative of mitochondrial respiration: OCR). Accumulation of MMP13 and phosphor AMPK (pAMPK) protein was quantified with Western blotting. Human and Bovine cartilage explants were cultured with L-1β in the presence or absence of 2DG (20 mM) and d 5-Aminoimidazole-4-carboxamide 1-β-D-ribofuranoside (AICAR) to pharmacologically induce AMPK for 7 days and stained with Safranin O.

Results:

Reduced mitochondrial potential and enhanced dependence on glycolysis was observed in IL-1β stimulated chondrocytes. Co-treatment with 4-MU and 2DG returned the cell metabolism to levels at or below baseline (Fig 1A, B). The Seahorse ATP Rate Assay means the contributions of glycolysis and mitochondrial respiration to chondrocyte ATP production (Fig 1C). In control chondrocytes, the use of glycolysis contributes to the majority of ATP produced (grey bars) approximately 1/5th from the TCA cycle (red bars). IL1β-activated chondrocytes display increase in glycolysis and decrease in mitochondrial contributions. These changes are reversed by co-treatment with 4MU and 2DG. As shown in Figs 2A, 2DG reversed the IL1β-induced increases accumulation of MMP13 protein in human OA chondrocytes by Western blotting analysis. Although IL-1β lost safranin O staining in human and bovine samples, co-incubation with 2DG blocked in the loss of proteoglycan (Fig 2B). pAMPK is associate with energy homeostasis in chondrocytes. IL-1β treatment decreased accumulation of phosphor AMPK. Co-treatment with 4-MU and 2DG resulted in a rescue of the pAMPK status (Figure 3A). Co treatment with AICAR, which is inducer of AMPK, also blocked in the loss of proteoglycan (Fig 3B).

Conclusion:

4-MU and 2DG have chondroprotective effect by changing metabolism and upregulate AMPK. We propose that 4MU and 2DG become useful when these endogenous responses are not enough to rescue cells from a pro-catabolic phenotype.

References:

[1]J. Biol. Chem. 291:12087, 2016; [2] J. Biol. Chem. 291:24105, 2016

Disclosure of Interests:

KENYA TERABE: None declared, Nobunori Takahashi Speakers bureau: AbbVie, Asahi Kasei, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eisai, Eli Lilly, Janssen, Mitsubishi Tanabe, Ono, Pfizer, Takeda, and UCB Japan, Ohashi Yoshifumi: None declared, Maeda Masataka: None declared, Warren Knudson: None declared, Cheryl Knudson: None declared, Toshihisa Kojima Grant/research support from: Chugai, Eli Lilly, Astellas, Abbvie, and Novartis, Consultant of: AbbVie, Speakers bureau: AbbVie, Astellas, Bristol-Myers Squibb, Chugai, Daiichi-Sankyo, Eli Lilly, Janssen, Mitsubishi Tanabe, Pfizer, and Takeda, Naoki Ishiguro Grant/research support from: AbbVie, Asahi Kasei, Astellas, Chugai, Daiichi-Sankyo, Eisai, Kaken, Mitsubishi Tanabe, Otsuka, Pfizer, Takeda, and Zimmer Biomet, Consultant of: Ono, Speakers bureau: Astellas, Bristol-Myers Squibb, Daiichi-Sankyo, Eli Lilly, Pfizer, and Taisho Toyama

Investigation of Ag and Cu Filament Formation Inside the Metal Sulfide Layer of an Atomic Switch Based on Point-Contact Spectroscopy

The atomic switches have attracted wide attention owing to their applications in nonvolatile electric devices. The atomic switch is operated by the formation and dissipation of a metallic filament inside a metal sulfide film, which is controlled by a solid electrochemical reaction. Although the metallic filament is considered to consist of metal atoms, the chemical species of the metallic filament are difficult to be identified due to challenges in observing the metallic filament inside the solid. In this study, we report the investigation on the metallic filament in the atomic switch with metal sulfide based on point-contact spectroscopy (PCS). By cooling the atomic switch, the switch voltage increased to 1 V, which allowed for the PCS measurement. The PCS revealed that the metallic filament was composed of Ag atoms in the case of the Pt/Ag₂S/Ag atomic switch. We applied this technique to the Pt/Cu₂S/Ag and Pt/Ag₂S/Cu atomic switches to uncover the formation process of the metallic filament. In both atomic switches, the chemical species of the metallic filament were Ag. The metal atoms were supplied from both the metal electrode and the sulfide layer.

Ionic decision-maker created as novel, solid-state devices

Decision-making is being performed frequently in areas of computation to obtain better performance in a wide variety of current intelligent activities. In practical terms, this decision-making must adapt to dynamic changes in environmental conditions. However, because of limited computational resources, adaptive decision-making is generally difficult to achieve using conventional computers. The ionic decision-maker reported here, which uses electrochemical phenomena, has excellent dynamic adaptabilities, as demonstrated by its ability to solve multiarmed bandit problems (MBPs) in which a gambler given a choice of slot machines must select the appropriate machines to play so as to maximize the total reward in a series of trials. Furthermore, our ionic decision-maker successfully solves dynamic competitive MBPs, which cause serious loss due to the collision of selfish users in communication networks. The technique used in our devices offers a shift toward decision-making using the motion of ions, an approach that could find myriad applications in computer science and technology, including artificial intelligence.

Magnetic Control of Magneto-Electrochemical Cell and Electric Double Layer Transistor

A magneto-electrochemical cell and an electric double layer transistor (EDLT), each containing diluted [Bmim]FeCl₄ solution, have been controlled by applying a magnetic field in contrast to the control of conventional field effect devices by an applied electric field. A magnetic field of several hundred mT generated by a small neodymium magnet is sufficient to operate magneto-electrochemical cells, which generate an electromotive force of 130 mV at maximum. An EDLT composed of hydrogen-terminated diamond was also operated by applying a magnetic field. Although it showed reversible drain current modulation with a magnetoresistance effect of 503%, it is not yet advantageous for practical application. Magnetic control has unique and interesting characteristics that are advantageous for remote control of electrochemical behavior, the application for which conventional electrochemical devices are not well suited. Magnetic control is opening a door to new applications of electrochemical devices and related technologies.

Nanoionic devices enabling a multitude of new features

In recent years, interesting nanoscale phenomena caused by physical or chemical effects due to local ion transfers near heterointerfaces using ionic conductors have been discovered, and the so-called "nanoionic devices" (which apply new functionalities gained by exploiting those phenomena) are being proposed. Up until now, nanoionic devices with unique functions that have been unattainable with conventional semiconductor devices have been developed. These devices include brain-type devices, completely solid-state electric-double-layer transistors, multi-functional on-demand-type devices, superconducting elements capable of modulating transition temperature, and so on. As for research and development on nanodevices for next-generation information and communication technologies, expected developments of these devices in the field of solid-state ionics are introduced based on the results of our research.

In Situ Tuning of Magnetization and Magnetoresistance in Fe3O4 Thin Film Achieved with All-Solid-State Redox Device

An all-solid-state redox device composed of Fe3O4 thin film and Li(+) ion conducting solid electrolyte was fabricated for use in tuning magnetization and magnetoresistance (MR), which are key factors in the creation of high-density magnetic storage devices. Electrical conductivity, magnetization, and MR were reversibly tuned by Li(+) insertion and removal. Tuning of the various Fe3O4 thin film properties was achieved by donation of an electron to the Fe(3+) ions. This technique should lead to the development of spintronics devices based on the reversible switching of magnetization and spin polarization (P). It should also improve the performance of conventional magnetic random access memory (MRAM) devices in which the ON/OFF ratio has been limited to a small value due to a decrease in P near the tunnel barrier.

Revival of "dead" memristive devices: case of WO3-x

Inappropriate operation could make a memristive device "dead" and cause the loss of resistive switching performance. In this study, the revival of "dead" devices was investigated in the case of WO3-x-based memristive devices. It is believed that inappropriate operation with a high-voltage pulse creates an ordered structure of oxygen vacancies and such an ordered structure makes the normal reset process fail. By precisely controlled voltage sweeping at certain compliance currents, a "dead" device can be revived. The revival operation disrupts the ordered structure by Joule heating and recovers Schottky-like barrier modulation-based switching.

Synaptic Metaplasticity Realized in Oxide Memristive Devices

Metaplasticity, a higher order of synaptic plasticity, as well as a key issue in neuroscience, is realized with artificial synapses based on a WO3 thin film, and the activity-dependent metaplastic responses of the artificial synapses, such as spike-timing-dependent plasticity, are systematically investigated. This work has significant implications in neuromorphic computation.

Size-Controlled AgI/Ag Heteronanowires in Highly Ordered Alumina Membranes: Superionic Phase Stabilization and Conductivity

Nanoscaled ionic conductors are crucial for future nanodevices. A well-known ionic conductor, AgI, exhibited conductivity greater than 1 Ω(-1) cm(-1) in α-phase and transformed into poorly conducting β-/γ-phase below 147 °C, thereby limiting applications. Here, we report that transition temperatures both from the β-/γ- to α-phase (Tc↑) and the α- to β-/γ-phase (Tc↓) are tuned by AgI/Ag heteronanowires embedded in anodic aluminum oxide (AAO) membranes with 10-30 nm pores. Tc↑ and Tc↓ shift to correspondingly higher and lower temperature as pore size decreases, generating a progressively enlarged thermal hysteresis. Tc↑ and Tc↓ specifically achieve 185 and 52 °C in 10 nm pores, and the final survived conductivity reaches ∼8.3 × 10(-3) Ω(-1) cm(-1) at room temperature. Moreover, the low-temperature stabilizing α-phase (down to 21 °C, the lowest in state of the art temperatures) is reproducible and survives further thermal cycling. The low-temperature phase stabilization and enhancement conductivity reported here suggest promising applications in silver-ion-based future nanodevices.

Effect of Ionic Conductivity on Response Speed of SrTiO3-Based All-Solid-State Electric-Double-Layer Transistor

An all-solid-state electric-double-layer transistor (EDLT) with a Y-stabilized ZrO₂ (YSZ) proton conductor/SrTiO₃ (STO) single crystal has been fabricated to investigate ionic conductivity effect on the response speed, which should be a key parameter for development of next-generation EDLTs. The drain current exhibited a 4-order-of-magnitude increment by electrostatic carrier doping at the YSZ/STO interface due to ion migration, and the behavior strongly depended on the operation temperature. An Arrhenius-type plot of the ionic conductivity (σ(i)) in the YSZ and t(c)⁻¹, which is a current-rise time needed for charge accumulation at the YSZ/STO interface, shows a synchronized variation, indicating a proportional relationship between the two parameters. Analysis of the σ(i)-t(c) diagram shows that, in contrast to conventional EDLTs, the response speed should reach picosecond order at room temperature by using extreme miniaturization and superionic conductors. Furthermore, the diagram indicates that plenty of solid electrolytes, which have not been used due to the lack of criteria for evaluation, can be a candidate for all-solid-state EDLTs exceeding the carrier density of conventional EDLTs, even though the response speed becomes comparably lower than those of FETs.

In situ and nonvolatile photoluminescence tuning and nanodomain writing demonstrated by all-solid-state devices based on graphene oxide

In situ and nonvolatile tuning of photoluminescence (PL) has been achieved based on graphene oxide (GO), the PL of which is receiving much attention because of various potential applications of the oxide (e.g., display, lighting, and nano-biosensor). The technique is based on in situ and nonvolatile tuning of the sp(2) domain fraction to the sp(3) domain fraction (sp(2)/sp(3) fraction) in GO through an electrochemical redox reaction achieved by solid electrolyte thin films. The all-solid-state variable PL device was fabricated by GO and proton-conducting mesoporous SiO2 thin films, which showed an extremely low PL background. The device successfully tuned the PL peak wavelength in a very wide range from 393 to 712 nm, covering that for chemically tuned GO, by adjusting the applied DC voltage within several hundred seconds. We also demonstrate the sp(2)/sp(3) fraction tuning using a conductive atomic force microscope. The device achieved not only writing, but also erasing of the sp(2)/sp(3)-fraction-tuned nanodomain (both directions operation). The combination of these techniques is applicable to a wide range of nano-optoelectronic devices including nonvolatile PL memory devices and on-demand rewritable biosensors that can be integrated into nano- and microtips which are transparent, ultrathin, flexible, and inexpensive.

In situ and non-volatile bandgap tuning of multilayer graphene oxide in an all-solid-state electric double-layer transistor

The sp(2) /sp(3) domain fraction of multilayer graphene oxide (GO) is tuned in situ and in a non-volatile manner by using a proton-induced redox reaction at the interface of GO and the yttria-stabilized zirconia proton-conductor. This method opens the door for transparent, ultrathin, flexible, and low cost carbon-nanoionics devices that can control not only electronic transport, but also other properties such as photoluminescence and optics.

Volatile and nonvolatile selective switching of a photo-assisted initialized atomic switch

A photo-assisted atomic switch, which has a photoconductive molecular layer in a gap of about 20 nm between an Ag2S electrode and a Pt electrode, is set to a conventional gap-type atomic switch operation mode by light irradiation with the application of a small bias that precipitates Ag atoms from an Ag2S electrode. After this initialization, the switch operates only with application of a bias. In this study, we also found that after the set-operation a photo-assisted initialized atomic switch shows different switching modes depending on the bias range, i.e., volatile switching when the applied bias is smaller than the threshold bias, and nonvolatile switching when the applied bias is larger than the threshold bias. These characteristics can be useful in reconfiguring a circuit such as in neural computing systems.

Synaptic plasticity and memory functions achieved in a WO3-x-based nanoionics device by using the principle of atomic switch operation

A compact neuromorphic nanodevice with inherent learning and memory properties emulating those of biological synapses is the key to developing artificial neural networks rivaling their biological counterparts. Experimental results showed that memorization with a wide time scale from volatile to permanent can be achieved in a WO3-x-based nanoionics device and can be precisely and cumulatively controlled by adjusting the device's resistance state and input pulse parameters such as the amplitude, interval, and number. This control is analogous to biological synaptic plasticity including short-term plasticity, long-term potentiation, transition from short-term memory to long-term memory, forgetting processes for short- and long-term memory, learning speed, and learning history. A compact WO3-x-based nanoionics device with a simple stacked layer structure should thus be a promising candidate for use as an inorganic synapse in artificial neural networks due to its striking resemblance to the biological synapse.

Room temperature redox reaction by oxide ion migration at carbon/Gd-doped CeO2 heterointerface probed by an in situ hard x-ray photoemission and soft x-ray absorption spectroscopies

In situ hard x-ray photoemission spectroscopy (HX-PES) and soft x-ray absorption spectroscopy (SX-XAS) have been employed to investigate a local redox reaction at the carbon/Gd-doped CeO2 (GDC) thin film heterointerface under applied dc bias. In HX-PES, Ce3d and O1s core levels show a parallel chemical shift as large as 3.2 eV, corresponding to the redox window where ionic conductivity is predominant. The window width is equal to the energy gap between donor and acceptor levels of the GDC electrolyte. The Ce M-edge SX-XAS spectra also show a considerable increase of Ce3+ satellite peak intensity, corresponding to electrochemical reduction by oxide ion migration. In addition to the reversible redox reaction, two distinct phenomena by the electrochemical transport of oxide ions are observed as an irreversible reduction of the entire oxide film by O2 evolution from the GDC film to the gas phase, as well as a vigorous precipitation of oxygen gas at the bottom electrode to lift off the GDC film. These in situ spectroscopic observations describe well the electrochemical polarization behavior of a metal/GDC/metal capacitor-like two-electrode cell at room temperature.

Quantized Conductance and Neuromorphic Behavior of a Gapless-Type Ag-Ta2O5 Atomic Switch

We investigated quantization behavior in conductance of an Ag/Ta2O5/Pt gapless-type atomic switch. Stepwise increases and decreases in the conductance were observed when small positive and negative bias voltages were applied to the Ag electrode, respectively, where each step corresponds to the conductance of a single atomic point contact. The conductance level could also be controlled by applying voltage pulses with varied amplitudes. Furthermore, when the interval time of consecutive input pulses was turned, we also observed long-term potentiation behavior similar to that of biological synapses. These results indicate that the oxide-based, gapless-type atomic switch has potential for use as a building block of neural computing systems.