POS1247 THE EFFECT OF IMMUNOSUPPRESSIVE AGENTS ON ANTIBODY FORMATION AFTER COVID-19 VACCINATION IN RHEUMATOID ARTHRITIS PATIENTS

Background

There is still controversy about the efficacy of COVID-19 vaccination and its extent in lowering immunogenicity of Rheumatoid Arthritis (RA) patients. The guideline in whether immunosuppressive agents need to be discontinued before the vaccination is continuously updated because it is considered to lower immunogenicity. Furthermore, there is great discussion on the effectiveness of the COVID-19 booster vaccine and interest in antibody generation in different types of vaccine, as in South Korea there are many patients who were prescribed the mRNA booster vaccine after two doses of ChAdOx1-S nCoV-19 vaccine.

Objectives

Thus, we investigated the differences of antibody production between patients who received only two doses of ChAdOx1-S nCoV-19 and those who received the mRNA booster vaccine. Also, antibody production under different types of immunosuppressive agents was analyzed.

Methods

From October 14, 2021 to January 21, 2022 at a tertiary referral center, two patient groups diagnosed with RA were studied prospectively; one group that completed 1st and 2nd doses of ChAdOx1-S nCoV-19 vaccine, second group that completed mRNA booster vaccine as well as two doses of ChAdOx1-S nCoV-19 vaccine. SARS-CoV-2 antibody testing on the semiquantitative anti-SARS-CoV-2 S enzyme immunoassay was done, and differences in antibody titers were analyzed in patients who received different immunosuppressive agents such as csDMARD, TNF inhibitor, JAK inhibitor, Tocilizumab, Abatacept and Corticosteroid. Statistical analysis with a multivariate logistic regression model was performed.

Results

In a total of 261 patients, 153 patients had completed two doses of ChAdOx1-S nCoV-19, 108 patients had completed third mRNA booster vaccine. Anti-SARS-CoV-2 RBD antibody positive rate (titer>0.8U/mL) was 97%(149/153) and 99%(107/108) respectively, and only 5 patients showed negative result. In the aspect of high antibody titer(>250U/mL), which is the upper limit of the RBD antibody immunoassay, the result showed rate of 31% (47/153) in the non-booster group and 94%(102/108) in the booster group respectively.

Among the different immunosuppressive agents and other clinical aspects, multivariate analysis revealed that corticosteroid use (OR 0.91; 95% CI: 0.86-0.98), older age(OR 4.33; 95% CI: 1.34-13.91), and male gender(OR 0.35; 95% CI 0.16-0.75) were significantly associated with low rate of high antibody titer.

Furthermore, out of 14 patients who underwent antibody test twice before and after the mRNA booster vaccine, other than four patients who already showed high titer of >250U/mL before the mRNA booster vaccine, 10 patients showed an increase in titer after the booster vaccine and 7 patients were acquired high titer of >250U/mL.

Figure 1.

Anti-SARS-CoV RBD antibody titer of two groups

Table 1.

Analysis of immunosuppressive agents and other clinical aspects for high antibody titer(>250U/mL) after two doses of ChAdOx1-S nCoV-19

Univariate analysisMultivariate analysisParameterOR95% CIp valueOR95% CIp valueClinical features Age0.9170.860-0.9780.0080.9170.857-0.9810.012 Sex3.6741.206-11.1910.0224.3301.348-13.9120.014 DAS 281.1440.670-1.9500.622 Duration0.9300.830-1.0430.214Medications csDMARD1.2730.639-2.5331.273 TNF inhibitor2.2110.795-6.1450.128 JAK inhibitor0.6650.275-1.6070.365 Abatacept0.3680.038-3.6020.391 Tocilizumab1.2640.438-3.6480.665 Corticosteroid0.4720.235-0.9490.0350.3490.163-0.7480.007Medication dose Methotrexate0.9930.919-1.0720.855 Corticosteroid0.8490.719-1.0030.054

Conclusion

Anti-SARS-CoV-2 RBD antibody positive rate was 97% or more regardless of the mRNA booster vaccination. However, patients who received the mRNA booster vaccine after two doses of ChAdOx1-S nCoV-19 vaccine showed high antibody titer (>250U/mL) three times more than those who did not receive the booster shot.

Our findings also showed that corticosteroid use, old age, and male gender is significantly associated with low rate of acquiring high antibody titer.

Disclosure of Interests

None declared

AB0476 PREDICTIVE FACTORS FOR THE DEVELOPMENT OF SYSTEMIC LUPUS ERYTHEMATOSUS IN PATIENTS WITH IMMUNE THROMBOCYTOPENIA

Background

Patients with immune thrombocytopenia (ITP) have a risk of developing systemic lupus erythematosus (SLE). We sought to examine the clinical characteristics of patients with primary ITP who later developed SLE, and identified the risk factors for the development of SLE.

Objectives

We retrospectively examined patients who were diagnosed with primary ITP at a tertiary hospital between August 2001 and November 2019. We compared the clinical characteristics according to the development of SLE. Logistic regression analysis was performed to identify the factors associated with the development of SLE.

Methods

Of 130 patients with primary ITP, 10 (7.7%) were later diagnosed with SLE during follow-up (median, 30 months [IQR, 15.5–105]). The presence of skin bleeding, organ bleeding, lymphopenia, anemia, and positive antinuclear antibody (ANA) titer (> 1:160) were more common among patients who later developed SLE than did those who did not develop SLE. Multivariate analysis showed that young age (< 40 years; odds ratio [OR], 8.359 [95% confidence interval (CI), 1.230–56.793]; p = 0.033), organ bleeding (OR, 18.349 [95% CI, 2.771–121.517]; p = 0.003), and ANA positivity (>1:160; OR, 7.692 [95% CI, 1.482–39.910]; p = 0.015) were significantly associated with the development of SLE.

Results

Young age (< 40 years), organ bleeding, and ANA positivity (> 1:160) were risk factors for the development of SLE in patients with primary ITP.

Conclusion

These results suggest that continued follow-up for the detection of SLE development is needed for patients with ITP, particularly those with young age, ANA positivity, or organ bleeding.

References

[1]Zhu, Fang-Xiao, et al. “Risk of systemic lupus erythematosus in patients with idiopathic thrombocytopenic purpura: a population-based cohort study.” Annals of the rheumatic diseases 79.6 (2020): 793-799.

Table 1.

Factors associated with the development of SLE in patients with primary ITP

UnivariateMultivariateOR95% CIP valueOR95% CIP valueYoung agea5.4441.332–22.2500.0188.3591.230–56.7930.033Female4.3330.530–35.4220.17BMI0.8730.717–1.0700.20Skin bleeding8.4191.034–68.5330.046Mucosa bleeding1.2500.247–6.3300.79Organ bleeding14.8643.633–60.815< 0.00118.3492.771–121.5170.003Platelet counts0.9110.828–1.0020.06ANA positivityb16.5003.984–68.341< 0.0017.6921.482–39.9100.015Neutropeniac2.1110.229–19.4990.51Lymphopeniad4.8461.189–19.7590.028Anemiae10.1182.044–50.0910.005

SLE: systemic lupus erythematosus, ITP: immune thrombocytopenia, BMI: body mass index, ANA: antinuclear antibody, OR: odds ratio, CI: confidence interval.

aYoung age = age < 40 years

bANA positivity ≥ 1:160

cNeutropenia = Absolute neutrophil count < 1500 μL

dLymphopenia = Absolute lymphocyte count < 1500 μL

eAnemia = Hemoglobin < 12 g/dL

Disclosure of Interests

None declared

AB0456 DISEASE FLARE OF SYSTEMIC LUPUS ERYTHEMATOSUS IN PATIENTS WITH END-STAGE RENAL DISEASE ON DIALYSIS

Background

The systemic lupus erythematosus (SLE) disease activity in patients with lupus nephritis (LN) generally declines after the initiation of renal replacement therapy (RRT); this is known as the “burn out” phenomenon that possibly occurs due to the suppression of cellular and humoral immunity in the end-stage renal disease (ESRD) state and elimination of disease pathogenic factor by dialysis [1-4]. However, several studies showed that SLE flares could occur even during RRT [5-8]. Nevertheless, the details of disease flares of SLE in patients under dialysis have not been studied yet.

Objectives

This study aimed to investigate the clinical features, risk factors, and treatment details of SLE patients experiencing disease flare under RRT.

Methods

The medical records of SLE patients who received dialysis at two tertiary referral hospitals in Seoul and Ulsan, South Korea were reviewed. All patients in this study were either clinically or histologically diagnosed with LN

Results

Of a total of 121 patients with SLE on dialysis, 96 (79.3%) were on hemodialysis (HD) and 25 (20.6%) were on peritoneal dialysis (PD). During a median follow-up of 45 months (IQR, 23–120) after the initiation of dialysis, 32 (26.4%) patients experienced SLE flare (HD, n = 25; PD, n = 7). The most common features of SLE flare were hematologic (40.6%) and constitutional manifestations (40.6%). Treatments for disease flares were based on corticosteroids, and 11 (34.3%) patients required additional immunosuppressants including cyclophosphamide and mycophenolate mofetil. There was no case of severe adverse events related to medication. non-renal SLE Disease Activity Index (SLEDAI) score before dialysis initiation (HR 1.235; 95% CI, 1.122–1.359; P = 0.001) was a significant risk factor for disease flare during dialysis.

Table 1.

Multivariable analysis of factors associated with SLE flare under dialysis

Hazard ratio95% CIP-valueNon-renal SLEDAI at the initiation of dialysis1.2351.122–1.3590.001Hematologic manifestation prior to dialysis1.2560.690–2.8260.150Cumulative amount of steroid during 1 year prior to the initiation of dialysis1.0400.995–1.0870.086Dialysis modality: hemodialysis0.7660.262–2.2430.630

Conclusion

More than one-quarter of SLE patients experienced disease flare during dialysis, which most commonly had hematologic manifestations. Continued follow-up and appropriate treatments including immunosuppressants should be considered for patients with SLE under dialysis.

References

[1]Coplon NS, Diskin CJ, Petersen J, Swenson RS. The Long-Term Clinical Course of Systemic Lupus Erythematosus in End-Stage Renal Disease. New England Journal of Medicine 1983;308:186-90.

[2]Lee P-T, Fang H-C, Chen C-L, Chiou Y-H, Chou K-J, Chung H-M. Poor prognosis of end-stage renal disease in systemic lupus erythematosus: a cohort of Chinese patients. Lupus 2003;12:827-32.

[3]Pahl MV, Gollapudi S, Sepassi L, Gollapudi P, Elahimehr R, Vaziri ND. Effect of end-stage renal disease on B-lymphocyte subpopulations, IL-7, BAFF and BAFF receptor expression. Nephrology Dialysis Transplantation 2010;25:205-12.

[4]Ribeiro FM, Fabris CL, Bendet I, Lugon JR. Survival of lupus patients on dialysis: a Brazilian cohort. Rheumatology 2013;52:494-500.

[5]Okano K, Yumura W, Nitta K et al. Analysis of Lupus Activity in End-Stage Renal Disease Treated by Hemodialysis. Internal Medicine 2001;40:598-602.

[6]Barrera-Vargas A, Quintanar-Martínez M, Merayo-Chalico J, Alcocer-Varela J, Gómez-Martín D. Risk factors for systemic lupus erythematosus flares in patients with end-stage renal disease: a case–control study. Rheumatology 2015:kev349.

[7]Cucchiari D, Graziani G, Ponticelli C. The dialysis scenario in patients with systemic lupus erythematosus. Nephrology Dialysis Transplantation 2014;29:1507-13.

[8]Kang S-H, Chung B-H, Choi S-R et al. Comparison of Clinical Outcomes by Different Renal Replacement Therapy in Patients with End-Stage Renal Disease Secondary to Lupus Nephritis. The Korean Journal of Internal Medicine 2011;26:60.

Disclosure of Interests

None declared

AB1273 MACROPHAGE ACTIVATION SYNDROME IN RHEUMATIC DISEASE: CLINICAL CHARACTERISTICS AND PROGNOSIS OF 20 PATIENTS

Background

Macrophage activation syndrome (MAS) is a hyperinflammatory condition that is known to be secondary hemophagocytic lymphohistiocytosis (HLH) in patients with rheumatic disease.

Objectives

The aim of study was to evaluate the clinical manifestations and outcomes in patients with MAS with rheumatic disease.

Methods

We performed a retrospective study of 20 adult patients who were diagnosed with MAS from 2012 to 2020. MAS was classified according to the HLH-2004 criteria. Patients’ information, including clinical features, laboratory findings, and treatment regimens, was collected, and the overall survival rate was estimated by the Kaplan–Meier method.

Results

Twenty patients (18 women, 35.6 ± 18.3 years) who met the HLH-2004 criteria also fulfilled the 2016 EULAR/ACR/PRINTO classification criteria for MAS, and HScore was higher than 169 (median, 238.5). Fourteen patients with systemic lupus erythematosus and 6 patients with adult-onset Still’s disease were included. All patients were treated initially with corticosteroids, and 16 patients required additional immunosuppressants. The overall survival at 3 and 6 months was 75.2% and 64.3%. In survivors, renal impairment was less common (23.1% versus 42.9%, p = 0.007), the levels of AST (202.0 versus 72.0 IU/L, p = 0.006) and LDH (1144.0 versus 343.0IU/L, p = 0.001), and platelet count (90.0 versus 46.0 × 109/L, p = 0.016) were higher in compared to non-survivors. Nine patients had opportunistic infections, five of whom died during admission.

Conclusion

The mortality of patients with MAS remains high. Renal impairment, levels of AST and LDH, and platelet count might be associated with prognosis.

Table 1.

Treatments and management characteristics of patients with MAS

No.Age/sexDiseaseDisease duration (months)1st Treatment (corticosteroids)2nd Treatment3rd TreatmentCombined infectionAlive/dead119/FSLE11 mg/kgIVIG + PPTCZ, RTXBacteremiaDead220/MSLE01 mg/kg---Alive320/FAOSD11 mg/kgVP16--Alive422/FSLE1100 mgIVIG + PP-PneumoniaDead522/FAOSD0500 mgIVIG--Alive623/FSLE1821 mg/kg---Alive723/FSLE411 mg/kg---Alive830/FSLE1461 mg/kgIVIGCsA-Alive932/FSLE1271 mg/kgIVIG + PPCsA, TCZPneumoniaAlive1035/FAOSD01 mg/kgCsA-Viral infectionAlive1137/FSLE651 mg/kgCsA, VP16-BacteremiaAlive1238/FSLE01 mg/kgIVIG + PPRTX-Dead1340/FAOSD00.5 mg/kgCsA--Alive1443/FSLE601 mg/kgIVIG + PPTCZ, RTX, CsA,PCP,DeadVP16, IFXViral infection1549/FSLE01 mg/kgCYC-BacteremiaAlive1651/FAOSD01 mg/kg---Alive1757/FSLE01 mg/kgIVIG + PPCsA, VP16Fungal infectionDead1861/FSLE21 mg/kgIVIG + PPTCZ-Dead1968/FSLE21 mg/kgIVIG + PPCsAFungal infectionAlive2070/MAOSD01 mg/kgIVIG + PPCsA, VP16Fungal infectionDead

SLE: Systemic lupus erythematosus, IVIG: Intravenous immunoglobulin, PP: Plasmapheresis, TCZ: Tocilizumab, RTX: Rituximab, AOSD: Adult-onset still’s disease, VP16: Etoposide, PCP: Pneumocystis pneumonia, CsA: Cyclosporin, IFX: Infliximab, MCTD: Mixed connective tissue disease.

Disclosure of Interests

None declared

POS0762 LONG-TERM RENAL OUTCOMES OF PATIENTS WITH NON-PROLIFERATIVE LUPUS NEPHRITIS

Background

Although proliferative (class III or IV) lupus nephritis (LN) is the most common finding in the classification of LN, pure membranous (class V) or mesangial (class I or II) LN can occur as a form of LN. Even though non-proliferative LN (class I, II, or V) is a less severe form with good outcomes, data on long-term renal prognosis are limited.

Objectives

This study investigated the long-term outcomes and prognostic factors in non-proliferative LN.

Methods

We retrospectively reviewed the medical records of patients with systemic lupus erythematosus who were diagnosed with LN class I, II, V or II+IV by kidney biopsy between 1997 and 2021 at a tertiary referral center. Clinical and laboratory data were compared between patients with and without poor renal outcomes. Poor renal outcome was defined as an estimated glomerular filtration rate (eGFR) of < 60 mL/min/1.73 m2 or death due to renal cause. Univariate and multivariate analyses were performed with the Cox proportional hazard model to identify the factors associated with poor renal outcomes.

Results

We included 71 patients with non-proliferative LN (4: class I; 17: class II; 48: class V, 17; 2: class II+V). Median follow-up duration was 103 months (interquartile range 27–185) and the overall rate of poor renal outcomes at last follow-up was 29% (21/71), including end-stage renal disease (n=2) and renal death (n=1).

Univariate analysis indicated that older age (HR 1.05; 95% CI: 1.00–1.09), low eGFR (HR 0.97; 95% CI: 0.95–0.99) and failure to reach complete remission at 6 months (HR 0.332; 95% CI: 0.12–0.92) were significantly associated with poor renal outcomes. Multivariate analysis revealed that low eGFR at 6 months (HR 0.97; 95% CI: 0.95–0.99) was significantly associated with poor renal outcomes.

Figure 1.

Renal outcomes at last follow up

eGFR, estimated glomerular filtration rate (ml/min/1.73m2)

Table 1.

Univariate and multivariate Cox proportional hazard regression analyses of the factor associated with poor renal outcomes

ParameterUnivariate analysisMultivariate analysisHR95% CIp valueHR95% CIp valueClinical features Age1.0461.003-1.0910.0361.0020.960-1.0470.921 Sex1.6540.375-7.2980.506 SLEDAI1.0360.965-1.1120.327 Extra renal SLEDAI1.0380.971-1.110.272Renal profiles eGFR at LN diagnosis0.9930.976-1.0110.456 Proteinuria at LN diagnosis1.0001.000-1.0000.444 > 1g/24 hours0.6690.243-1.8410.437  > 3g/24 hours0.6240.229-1.6990.356 eGFR at 6M0.9670.948-0.9860.0010.9680.948-0.9880.002 eGFR at 12M0.9640.947-0.9810.000 Complete remission at 6M0.3320.119-0.9240.0350.5530.179-1.7070.303 Complete remission at 12M0.6670.232-1.9140.451 Transformation1.2460.423-0.7010.692Laboratory data Anti-dsDNA1.0010.999-1.0030.196 C31.0201.000-1.0410.051 C41.0270.969-1.0890.367 Albumin1.1800.661-2.1090.576ClassificationaClass I0.8020.102-6.3030.834Class II1.2980.412-4.0880.656Class V0.8870.308-2.5570.824Class II+V0.0480.000-16850.837Medicationsb ACEi/ARB1.6520.603-4.5280.329 Hydroxychloroquine1.3260.414-4.2420.635 Corticosteroid1.1860.154-9.1080.870 CNI2.4390.464-12.8240.292 MMF3.7880.959-14.9650.057  　 AZA0.5890.133-2.6110.486

a LN classifications were based on the International Society of Pathology/Renal Pathology Society (ISN/RPS) classification.

b Medications maintained at least one year since Lupus Nephritis diagnosis.

HR, hazard ratio; 95% CI, 95% confidence interval; SLEDAI, systemic lupus erythematosus disease activity index; eGFR, estimated glomerular filtration rate; LN, lupus nephritis; anti-dsDNA, anti-double strand DNA; C3/C4; complement 3/4; ACEi, angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker; CNI, carcineurin inhibitor; MMF, mycophenolate mofetil; AZA, azathioprine.

Conclusion

Poor renal outcomes occurred in approximately 30% of patients with non-proliferative LN (class I, II or V) after long-term follow-up.

Our findings suggest that more active management may be needed for non-proliferative LN, particularly in patients with low eGFR at 6 months.

Disclosure of Interests

None declared

Social determinants of health influence disease activity and functional disability in Polyarticular Juvenile Idiopathic Arthritis

BACKGROUND

Social determinants of health (SDH) greatly influence outcomes during the first year of treatment in rheumatoid arthritis, a disease similar to polyarticular juvenile idiopathic arthritis (pJIA). We investigated the correlation of community poverty level and other SDH with the persistence of moderate to severe disease activity and functional disability over the first year of treatment in pJIA patients enrolled in the Childhood Arthritis and Rheumatology Research Alliance Registry.

METHODS

In this cohort study, unadjusted and adjusted generalized linear mixed effects models analyzed the effect of community poverty and other SDH on disease activity, using the clinical Juvenile Arthritis Disease Activity Score-10, and disability, using the Child Health Assessment Questionnaire, measured at baseline, 6, and 12 months.

RESULTS

One thousand six hundred eighty-four patients were identified. High community poverty (≥20% living below the federal poverty level) was associated with increased odds of functional disability (OR 1.82, 95% CI 1.28-2.60) but was not statistically significant after adjustment (aOR 1.23, 95% CI 0.81-1.86) and was not associated with increased disease activity. Non-white race/ethnicity was associated with higher disease activity (aOR 2.48, 95% CI: 1.41-4.36). Lower self-reported household income was associated with higher disease activity and persistent functional disability. Public insurance (aOR 1.56, 95% CI 1.06-2.29) and low family education (aOR 1.89, 95% CI 1.14-3.12) was associated with persistent functional disability.

CONCLUSION

High community poverty level was associated with persistent functional disability in unadjusted analysis but not with persistent moderate to high disease activity. Race/ethnicity and other SDH were associated with persistent disease activity and functional disability.

Realizing topologically ordered states on a quantum processor

[Figure: see text].

Removing leakage-induced correlated errors in superconducting quantum error correction

Quantum computing can become scalable through error correction, but logical error rates only decrease with system size when physical errors are sufficiently uncorrelated. During computation, unused high energy levels of the qubits can become excited, creating leakage states that are long-lived and mobile. Particularly for superconducting transmon qubits, this leakage opens a path to errors that are correlated in space and time. Here, we report a reset protocol that returns a qubit to the ground state from all relevant higher level states. We test its performance with the bit-flip stabilizer code, a simplified version of the surface code for quantum error correction. We investigate the accumulation and dynamics of leakage during error correction. Using this protocol, we find lower rates of logical errors and an improved scaling and stability of error suppression with increasing qubit number. This demonstration provides a key step on the path towards scalable quantum computing.

Pre-Transplant Marital Status and Hematopoietic Cell Transplantation Outcomes

Background

Evidence about the impact of marital status before hematopoietic cell transplantation (hct) on outcomes after hct is conflicting.

Methods

We identified patients 40 years of age and older within the Center for International Blood and Marrow Transplant Research registry who underwent hct between January 2008 and December 2015. Marital status before hct was declared as one of: married or living with a partner, single (never married), separated or divorced, and widowed. We performed a multivariable analysis to determine the association of marital status with outcomes after hct.

Results

We identified 10,226 allogeneic and 5714 autologous hct cases with, respectively, a median follow-up of 37 months (range: 1-102 months) and 40 months (range: 1-106 months). No association between marital status and overall survival was observed in either the allogeneic (p = 0.58) or autologous (p = 0.17) setting. However, marital status was associated with grades 2-4 acute graft-versus-host disease (gvhd), p < 0.001, and chronic gvhd, p = 0.04. The risk of grades 2-4 acute gvhd was increased in separated compared with married patients [hazard ratio (hr): 1.13; 95% confidence interval (ci): 1.03 to 1.24], and single patients had a reduced risk of grades 2-4 acute gvhd (hr: 0.87; 95% ci: 0.77 to 0.98). The risk of chronic gvhd was lower in widowed compared with married patients (hr: 0.82; 95% ci: 0.67 to 0.99).

Conclusions

Overall survival after hct is not influenced by marital status, but associations were evident between marital status and grades 2-4 acute and chronic gvhd. To better appreciate the effects of marital status and social support, future research should consider using validated scales to measure social support and patient and caregiver reports of caregiver commitment, and to assess health-related quality of life together with health care utilization.

AB0212 FLARE RISK AFTER DISCONTINUING LONG-TERM METHOTREXATE TREATMENT IN PATIENTS HAVING RHEUMATOID ARTHRITIS WITH LOW DISEASE ACTIVITY

Background:

Several recent studies have reported that MTX could be discontinued in patients with low disease activity who are taking biologic DMARDs or tofacitinib. However, there are limited studies on whether MTX could be discontinued in patients with low disease activity who have taken MTX for a long term.

Objectives:

We investigated the disease flare rate in patients with rheumatoid arthritis (RA) who achieved low disease activity following long-term methotrexate (MTX) treatment and the factors related to flare.

Methods:

This retrospective longitudinal cohort study included patients with RA and low disease activity who were exposed to MTX for >10 years. Disease flare was defined as an increase in DAS28 of >1.2 within 6 months of discontinuation of MTX. Logistic regression analysis was performed to identify the factors associated with flare.

Results:

In total, 97 patients with RA were included in the study. The mean baseline DAS28 was 1.96 ± 0.56. The median cumulative MTX dose was 11.7g; the median duration of exposure to MTX was 19 years. Following MTX discontinuation, flare occurred in 43 (44.3%) patients; the mean time to flare was 98 ± 37.7 days. According to univariable logistic regression analysis, C-reactive protein, erythrocyte sedimentation rate (ESR) at discontinuation, the average ESR in the 6 months before discontinuation of MTX, a weekly dose of MTX before discontinuation, and use of other conventional synthetic DMARDs were associated with a higher risk of disease flare. In multivariable analysis, a weekly dose of MTX before discontinuation (OR, 1.014; 95% CI, 1.014–1.342; p = 0.031) was significantly associated with flare risk.

Conclusion:

Among patients with RA who achieved low disease activity with long-term treatment with MTX, more than half of the patients remained flare free after MTX discontinuation. A higher MTX dose before discontinuation was associated with a high flare risk.

Disclosure of Interests:

None declared

FRI0118 RISK OF LIVER FIBROSIS ON TRANSIENT ELASTOGRAPHY IN PATIENTS WITH RHEUMATIC DISEASE UNDER LONG-TERM METHOTREXATE TREATMENT

Background:

Methotrexate (MTX) is a cornerstone drug for the treatment of rheumatic disease and low doses of MTX are both tolerable and safe, with monitored toxicity, assessed via the liver function test. However, there is still controversy regarding the risk of liver fibrosis with long-term use of MTX. Transient elastography is commonly used to assess and monitor fibrosis progression in patients with chronic liver disease.

Objectives:

The present study aims to investigate liver fibrosis using transient elastography and related factors in patients with rheumatic disease receiving long-term MTX.

Methods:

The present retrospective, longitudinal, cross-sectional study included patients with an autoimmune disease who are taking cumulative MTX dosed over 7 g, and who had liver fibrosis upon examination using transient elastography. Liver fibrosis was defined as liver stiffness, valued over 7.2 kPa. Logistic regression analysis was performed to identify factors associated with liver fibrosis, and receiver operating characteristics analysis was used to determine the predictive value of each factor.

Results:

We included 83 patients with autoimmune disease, with a median MTX cumulative dose of 11.6 (range 7.3-16.0) g. Sixty-eight patients (81.9%) had rheumatoid arthritis (RA), and 13 patients (15.7%) had Takayasu arteritis. The median MTX exposure duration was 18 (range 9-31) years. The median liver stiffness value was 4 (range 1.8-10.2) kPa. Five patients (6%) showed liver fibrosis (3 patients; RA, 2 patients; Takayasu arteritis). In the linear regression analysis, cumulative MTX dose showed a tendency towards a positive correlation with increasing liver stiffness value (r2 =0.039, p = 0.074). In the logistic regression analysis, cumulative MTX dose was associated with a higher risk of liver fibrosis (OR: 1.734, 95% CI: 1.060–2.837, p = 0.029). In addition, cumulative MTX dose had an area under the curve (AUC) of 0.813 (95% CI 0.695-0.930) and a sensitivity of 80% and specificity of 71.8% at a cut-off value of 12.7 g.

Conclusion:

Liver fibrosis was observed in 6% of patients with long-term MTX use and higher cumulative MTX doses increased the risk of liver fibrosis. Thus, transient elastography should be considered in patients exposed to high cumulative doses of MTX.

Disclosure of Interests:

None declared

THU0210 EARLY DISCONTINUATION OF TOFACITINIB IN PATIENTS WITH RHEUMATOID ARTHRITIS CO-TREATED WITH RIFAMPIN FOR LATENT TUBERCULOSIS: RESULTS FROM THE REAL-WORLD DATA

Background:

Rheumatoid arthritis (RA) patients need to undergo screening and receive treatment for latent tuberculosis infection (LTBI) before starting tofacitinib, which is primarily metabolized by cytochrome P450 (CYP) 3A4. Among chemoprophylactic agents, rifampin is known to be a potent CYP3A4 inducer; therefore, it is expected to decrease the efficacy of tofacitinib. However, tofacitinib and rifampin have been co-administered practically because of the short duration of chemoprophylaxis.

Objectives:

The aim of this study was to determine the efficacy of tofacitinib on co-administration with rifampin.

Methods:

Biologic-naïve RA patients treated with tofacitinib were selected, and electronic medical reports were reviewed retrospectively. All patients underwent screening for LTBI before starting tofacitinib, and patients with positive results were treated to prevent progression to active tuberculosis. To evaluate the efficacy of tofacitinib with or without rifampin, the discontinuation rates of tofacitinib were examined during the first 6 months. Kaplan–Meier analysis was used to construct cumulative discontinuation curves, and comparisons were performed using the log-rank test.

Results:

Among 81 patients who started tofacitinib, 21 (25.9%) were LTBI-positive and 18 (22.2%) were administered rifampin concomitantly with tofacitinib. The median follow-up time was 6 months in both patients who received rifampin (interquartile range [IQR] 2.21, 6.00) and those who did not receive rifampin (IQR 5.97, 6.00) (p = 0.083). There were no significant differences between patients who received rifampin and those who did not receive rifampin in all baseline characteristics, except the swollen joint count (3.00 [1.75, 5.25] vs. 5.00 [4.00, 7.00]; p = 0.025), at the time of starting tofacitinib. In patients who received rifampin at the time of starting tofacitinib, the mean duration of co-administration was 47.00 ± 23.54 days (median 56; IQR 28.75, 59.00). During follow-up, 14 of the 81 patients (17.3%) discontinued tofacitinib. As shown in the Figures 1 and 2, the discontinuation rate of tofacitinib within the first 6 months was significantly higher among patients who received rifampin for LTBI than among those who did not receive rifampin (lack of efficacy: 24.7% vs. 5.1%, p = 0.008; all causes: 38.9% vs. 11.2%, p = 0.002). Seven patients discontinued tofacitinib because of uncontrolled RA activity, and rifampin had been administered concomitantly in four of these seven patients. Of the four patients, three stopped taking tofacitinib in the middle of LTBI treatment, and the DAS28-ESR scores of these patients were higher at discontinuation than at baseline.

Conclusion:

Discontinuation rates were higher in RA patients who started tofacitinib during chemoprophylaxis involving rifampin than in those who did not receive rifampin. Physicians should be aware that the efficacy of tofacitinib could be decreased by the chemoprophylactic regimen for tuberculosis.

Disclosure of Interests:None declared

SAT0009 ROLE OF EC-18 IN AUTOIMMUNE ARTHRITIS AND INTERSTITIAL LUNG DISEASE IN CURDLAN-ADMINISTERED SKG MICE

Background:

Although the mortality of patients with rheumatoid arthritis (RA), for which interstitial lung disease (ILD) is one of the major contributors, has still not decreased, new target therapies for RA have shown good response in peripheral arthritis. EC-18 (acetylated diacylglycerol 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol) is a mono-acetyl-diglyceride that has been isolated from the antlers of sika deer and can be chemically synthesized from glycerol, palmitic acid, and linoleic acid. Research using LPS-induced acute lung injury murine model has reported that EC-18 stimulates a more rapid resolution of LPS-induced lung Inflammation. In addition, it has been reported that in a murine model of collagen-induced arthritis, EC-18 treatment ameliorated arthritis, with down-regulation of IL-6 level by regulating the activity of STAT3 in the synovium. Curdlan-administered SKG mice develop ILD spontaneously followed by peripheral arthritis, which resembles RA-ILD.

Objectives:

We evaluated the modulatory effect of the EC-18 on arthritis and ILD in autoimmune arthritis animal model.

Methods:

Male SKG mice were obtained from Dr. S. Sakaguchi. We injected curdlan (3 mg/mice) in 8-week-old SKG mice and identified the presence of ILD by histological analysis at 20 weeks post-injection. Arthritis score was measured every week for up to 20 weeks. EC-18 (250 mg/kg body weight/day, Enzychem Lifesciences Co., Daejeon, Korea) was administered every day orally. At 20 weeks post-injection, lung sections were stained with H&E and Masson’s trichrome. Using the Opal method, multiplexed immunofluorescent staining of lung tissue was performed. According to the scale by Ashcroft et al., fibrosis severity of lung sections was assessed by a system of eight grades. Analysis of serum cytokines by the luminex multiplex cytokine assay was performed at 20 weeks post-injection.

Results:

Oral administration of EC-18 decreased arthritis score significantly until 8 weeks post-injection and remained unchanged thereafter. At 20 weeks post-injection, histological analysis showed severe pulmonary destruction, including bronchial alveolar tissue damage and massive leukocyte infiltration, and fibrosis in the curdlan-administered mice, which was attenuated in EC-18 treated mice. In particular, 67% of curdlan-administered mice showed ILD-like phenotype, whereas the incidence rate in EC-18-treated mice was 17%. Furthermore, immunofluorescent-staining showed both IL-17A and neutrophil accumulation in lung in curdlan-administered mice; these were decreased in EC-18-treated mice. Interestingly, at 20weeks post-injection, EC-18 treatment down-regulated serum levels of IL-6 and TNF-α and up-regulated sIL-7Rα (anti-fibrotic molecule).

Conclusion:

Taken together, EC-18 exerts an anti-arthritic effect in early phase, but a long-term effect was not indicated. We emphasize the effect on ILD prevention of EC-18 via up-regulation of sIL-7Rα and inhibition of neutrophil accumulation, suggesting a therapeutic agent potentially for RA-ILD.

Disclosure of Interests:

None declared

OP0023 PREDICTION OF REMISSION FOR EACH BIOLOGICS BASED ON PATIENT’S CLINICAL INFORMATION BEFORE STARTING BIOLOGICS USING EXPLAINABLE ARTIFICIAL INTELLIGENCE: DATA FROM THE KOREAN COLLEGE OF RHEUMATOLOGY BIOLOGICS REGISTRY

Background:

Many studies have identified predictive factors of response to biologics in patients wirh rheumatoid arthritis (RA). However, there is still a lack in using them in daily clinical practice. Therefore, it is necessary to develop a method that can assist the physician in selecting effective biologics.

Objectives:

The purpose of this study is to establish machine learning model that predicts remission in patients treated with biologics using data of RA patients from the Korean College of Rheumatology Biologics (KOBIO) registry, and to identify the important features that have the most influence on the response to biologics using explainable artificial intelligence (AI).

Methods:

A total of 1,527 patients who started with biologics such as etanercept, adalimumab, golimumab, infliximab, abatacept, and tocilizumab from December 2012 to June 2019 were enrolled. Remission was predicted using 46 variables corresponding to baseline profiles at the starting of each biologics. We used five machine learning methods such as lasso, ridge, SVM, random forest, and XGBoost. For explainability of those models, we used Shapley plot to interpret the feature importance for each biologics.

Results:

In all machine learning methods, the accuracy and the area under the receiver operating characteristic (AUROC) were 57.2%~74.5%, 0.547~0.747, respectively (Table 1). The accuracy and AUROC of each biologics were similar between machine learning methods. Figure 2 showed interpretation of feature importance with the Shapley plot for remission. The most important feature was age in adalimumab (younger were closer to remission), daily corticosteroid dose in etanercept, golimumab, and all TNF inhibitors (using fewer doses daily were closer to remission), baseline erythrocyte sedimentation rate in infliximab (lower ESR were closer to remission), disease duration in abatacept (longer disease durations showed difficulty determining remission), baseline c-reactive protein in tocilizumab (higher CRP were closer to remission).

Table.

Predicting remission for all biologics in various machine learning method.

MeasureLassoRidgeSVMRandom ForestXGBoostNo info rateSampleAbataceptAccuracy74.1%74.1%70.6%71.8%68.8%70.6%216AUROC0.7250.7420.7070.6770.6470.500AdalimumabAccuracy73.6%72.0%70.4%72.0%70.4%68.8%315AUROC0.7100.7290.7000.6750.6630.500EtanerceptAccuracy72.0%72.0%70.0%71.5%70.0%68.0%250AUROC0.7410.7470.7260.7190.7040.500GolimumabAccuracy71.3%68.5%66.7%68.5%68.5%68.5%138AUROC0.7460.7270.7010.6900.6550.500InfliximabAccuracy72.8%73.5%67.6%73.5%69.1%72.5%172AUROC0.6630.6830.6160.5970.5270.500TNF inhibitorsAccuracy73.9%74.5%73.9%74.2%73.6%70.3%875AUROC0.7390.7410.7260.7470.7240.500TocilizumabAccuracy62.4%63.6%62.4%59.5%57.2%59.5%436AUROC0.6330.6400.6330.6150.5470.500Figure 2.

Shapley plots and SHAP values for the feature importance from clinical information in patients with RA.

Conclusion:

We developed machine learning models for predicting remission as a response to each biologics in active RA patients based on their clinical profiles, and found important clinical features using explainable AI. This approach may support clinical decisions to improve treatment outcomes in patients with RA.

Disclosure of Interests:

None declared