S. Kwon

Commissioning of the PLS-II

After 14 years of successful operation, the Pohang Light Source (PLS) has completed PLS-II upgrade to meet the increasing demand from the growing user community. The PLS-II upgrade has increased the beam energy from 2.5 GeV to 3 GeV; the number of insertion devices has been increased by a factor of two (20 IDs); and the beam current has been increased to 400 mA from 200 mA. The beam emittance has been reduced to below 10 nm while retaining the existing PLS tunnel as well as the existing injection system. During the six months of commissioning in the latter half of 2011, we have successfully achieved 14 insertion device operations and top-up operations with 100 mA beam current and 5.8 nm beam emittance. In this paper, we report the experimental results obtained from the PLS-II commissioning.

AB0855 The disparities between fracture risk assessment (FRAX) with bmd and without BMD in korean patients with ankylosing spondylitis- multicenter trial

Objectives The aims of this study are to determine the proportion of patients with ankylosing spondylitis (AS) at high risk for major osteoporotic and hip fractures of Fracture risk assessment (FRAX) in Korean and to determine if a care gap exists for high risk. Methods This study is a multicenter study including 163 AS patients in 5. All of the AS patients fulfilled the modified New York criteria. The classification of osteoporosis according to WHO criteria was based on T-score ≤ -2.5. The FRAX criteria for high risk of osteoporotic fracture, which is 10-year probability of ≥20% for major osteoporotic fracture or ≥3% for hip fracture, were calculated by the FRAX tool including the bone mineral density (BMD) values. We assessed various demographic factors, clinical and laboratory findings of AS, and medication use for AS and osteoporosis, and then evaluated the risk factors for osteoporotic fracture. Results The mean age of AS patients was 44.3 years, and 42 patients were female (25.2%) with 23 postmenopausal women 56.1%. Osteoporotic fracture was detected in 16 (9.8%) patients with AS. Among the 16 patients ≥65 years of age, 2 (12.5%) and 8 (50%) were at high risk for a major osteoporotic fracture (10-year probability >20%) and hip fracture (>3%), respectively. Among patients with BMD measurements (n=106), the 10-year risk of a major osteoporotic fracture and hip fracture calculated with BMD was significantly higher than in those without BMD measurements (P=0.001, P=0.002) respectively. The 10-year risk of a major osteoporotic and hip fracture fracture calculated with BMD was significantly higher than in those without BMD measurements (P<0.001, P=0.003) respectively among male patients with BMD measurements (n=74). There is no statistic difference of the 10-year risk of a major osteoporotic fracture and hip fracture between those calculated with BMD and those without BMD measurements (P>0.05) respectively among female patients (n=32). Conclusions A substantial gap exists between FRAX with BMD and without BMD in Korean patients with AS. Disclosure of Interest None declared

FRI0533 Incidence and risk factors of osteoporotic fracture in patients with rheumatoid arthritis: a multicenter comparative study of the frax criteria and who criteria

Background The fracture risk assessment tool (FRAX) criteria and the bone mineral density (BMD) criteria of the World Health Organization (WHO) are widely used for the assessment of osteoporotic fracture. Rheumatoid arthritis (RA) is the only disease parameter for the evaluation of osteoporotic fracture in the FRAX model, unlike the WHO criteria. However, the input for RA is just a dichotomous variable in FRAX model. Objectives In this study, we evaluated the incidence and risk factors of osteoporotic fracture in patients with RA through the comparison of the FRAX criteria and WHO criteria. Methods This study is a multicenter study, including 479 RA patients in 5 hospitals and 384 healthy controls, between January 2012 and December 2016. All of the RA patients fulfilled the 1987 American College of Rheumatology (ACR) criteria or the 2010 ACR/European League Against Rheumatism (EULAR) criteria for RA. The FRAX criteria for high risk of osteoporotic fracture, which is a 10-year probability of ≥20% for major osteoporotic fracture or ≥3% for hip fracture, were calculated by the FRAX tool including the BMD values. The classification of osteoporosis, according to WHO criteria were based on T-score ≤ -2.5. We assessed various demographic factors, clinical and laboratory findings of RA, and medication use for RA and osteoporosis, and then evaluated the incidence and risk factors for osteoporotic fracture. Results The mean age of RA patients was 61.7±11.9 years, and 426 patients were female (88.9%) with 353 postmenopausal women (82.9%). The BMD score of L-spine in RA patients was significantly lower than that in healthy control (-2.21±1.41 vs. 0.97±0.11, p<0.001). Osteoporotic fracture was detected in 81 (16.9%) patients with RA. In RA patients, 226 (47.2%) patients met the FRAX criteria for high risk of osteoporotic fracture, and 240 (50.1%) patients satisfied the WHO criteria. The result of the FRAX criteria was affected by the female sex, menopause, smoking, drinking, higher dose of glucocorticoid (≥5mg/day), vitamin D use, calcium use and proton pump inhibitor (PPI) use (p<0.05). In multiple linear analysis, the FRAX score to 10-year probability of ≥3% of hip fracture was associated with age (β=0.384, p<0.001), body weight (β=-0.110, p=0.038), erythrocyte sedimentation rate level (β=0.125, p=0.010), glucocorticoid dose (β=0.105, p=0.024), and PPI use (β= -0.123, p=0.010). The independent risk factors for FRAX criteria were age (OR 1.160, p<0.001), female sex (OR 3.942, p=0.010), body mass index (BMI) (OR 0.869, p=0.001), glucocorticoid dose (OR 1.167, p=0.025) and PPI use (OR 2.552, p=0.019), and those for WHO criteria were age (OR 1.021, p=0.040), glucocorticoid dose (OR 1.109, p=0.046) and smoking (OR 2.924, p=0.031). Conclusions Osteoporotic fractures were found in 16.9% of RA patients. The proportion of patients with high risk of osteoporotic fracture was 47.2% in the FRAX model and 50.1% in the WHO model. Age, female sex, lower BMI, higher dose of glucocorticoid, PPI use and smoking were independent risk factors for osteoporotic fracture in RA patients. Disclosure of Interest None declared

SAT0137 Bone mineral density measurement intervals for seropositive rheumatoid arthritis patients not treated for osteoporosis

Background Osteoporosis occurs more frequently in rheumatoid arthritis (RA) patients than in healthy individuals. However the appropriate interval for the bone mineral density (BMD) measurement in RA patients is not well established. Objectives This study investigated the effective BMD measurement interval and the risk factors associated with the development of osteoporosis for RA patients. Methods A retrospective study was performed on 511 RA patients aged more than 40 years old who had undergone BMD (DXA, GE LUNAR PRODIGY ADVANCE) testing more than once and who had normal BMD or osteopenia at the baseline BMD test and no history of any fracture of the spine or femur. The subjects were categorized into four subgroups: normal BMD (T-score > -1), mild (-1 ≥ T-score > -1.5), moderate (-1.5 ≥ T-score > -2), and advanced (-2 ≥ T-score > -2.5) osteopenia. The BMD testing interval was defined as the estimated time for 10% of the RA patients to make the transition into osteoporosis without osteoporotic fracture or the administration of any osteoporosis drug. Results The observation period was 2,214 patient-years, with an average of 4.3 years. The estimated BMD testing interval was more than 10 years for normal, 4.3 years for mild, 2.5 years for moderate, and 1.5 years for advanced osteopenia in each of the RA patient groups.Table 1. Interval between baseline BMD testing and the development of osteoporosis Baseline BMD Mean interval to develop osteoporosis (year) Mean interval to develop osteoporosis in 10% of each group (year) Lumbar spine Femur neck Lumbar spine Femur neck Normal 9.4 (9.29–9.49)a 9.4 (9.25–9.53)a >10 >10 Mild osteopenia 9.2 (8.58–9.71)a 9.1 (8.94–9.22)a 4.3 >10 Moderate osteopenia 7.9 (6.94–8.76)a 9.4 (8.93–9.87)a 2.5 7.5 Advanced osteopenia 5.4 (4.61–6.21)a 8.6 (7.68–9.50)a 1.5 2.2 BMD, bone mineral density. aMean (95% confidence interval). Conclusions Our study indicated that in normal or osteopenic RA groups, a baseline BMD T-score is the most important factor in estimating the interval in which osteoporosis is predicted to occur. In addition, we recommend that the BMD measuring interval should be greater than 10 years in normal BMD RA patients, 4 years in mild, 2 years in moderate, and 1 year in advanced osteopenic RA patients on the basis of L-spine BMD. Disclosure of Interest None declared

AB0392 Safety and effectiveness of CT-P13 in patients with rheumatoid arthritis: results from 24 months nationwide registry in korea

Background CT-P13 is approved in both European Union and United States, and licensed for use in 79 countries around the world as a biosimilar to innovator infliximab (INX). The independent registries of CT-P13 have been conducted in a number of European countries and Korea [1]. Objectives To evaluate safety and effectiveness of CT-P13 when administered in a real-life setting in active RA patients. Methods This study collected data of patients who were treated with CT-P13 from 2013 December to 2016 June. Efficacy was assessed at baseline and every 6 months thereafter using DAS28 (ESR) and/or DAS28 (CRP) and collection of adverse events (AEs) was performed. Immunogenicity was assessed at baseline, Week 30 and every year during CT-P13 treatment period. Results Total 125 patients were enrolled; 104 patients started treatment with CT-P13 (Naïve group) and 21 patients (8 from INX, 13 from other anti-TNFs) switched treatment to CT-P13 (Switching group). The mean (SD) duration since RA diagnosis was 6.5 (±6.85) years for all patients. Of all patients treated with CT-P13, only 4.8% (6/125) of patients changed to other anti-TNFs. Two of six patients changed treatment within 8 month after starting CT-P13. The proportion of patients achieving clinical remission by DAS28 (ESR/CRP) increased gradually (Figure 1). DAS28 (ESR/CRP) value decreased from baseline at 6 months and it maintained thereafter (Table 1). Switching group also showed similar results that remission rate by DAS28 (CRP) was 42.9% (3/7) and mean actual value was 2.85 at 12 months. For Naïve group, 50% (52/104) of patients had at least one positive anti-drug antibody result and it is consistent to other published study [2]. Overall safety summarized as the percentage of patients with at least one treatment emergent AE (TEAE) was similar or lower after switching to CT-P13 (Table 2). No cases of active tuberculosis were reported.Table 1. DAS28 in CT-P13 Naïve group over 24 months Baseline 6 months 12 months 18 months 24 months DAS28 (ESR) n 67 62 40 14 3 Mean 5.78 3.61 3.30 3.01 2.42 SD 1.14 1.40 1.22 1.03 0.74 DAS28 (CRP) n 63 61 39 14 3 Mean 5.06 2.97 2.59 2.35 1.81 SD 1.19 1.21 1.06 0.69 0.63Table 2. Safety results in CT-P13 Naïve and Switching group Naïve group Switching group TEAEs 80.8% (84/104) 66.7% (14/21) Related TEAEs 31.7% (33/104) 28.6% (6/21) Infection and Infestation 42.3% (44/104) 33.3% (7/21) Conclusions The overall safety profile revealed that CT-P13 is well-tolerated in patients with RA and remission rate for 24 months also showed that CT-P13 is efficacious under real world practice. References Glintborg et al. ACR 2016. Krintel et al. Rheumatology 2013. Disclosure of Interest None declared

SAT0154 Effectiveness and safety of CT-P13 in patients with rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis and plaque psoriasis: observational study in republic of korea

Background CT-P13 is approved as a biosimilar of innovator infliximab for marketing in 79 countries around the world. After approval, observational study has been conducted in Republic of Korea in patients with Rheumatoid Arthritis (RA), Ankylosing Spondylitis (AS), Psoriatic Arthritis (PsA) and Plaque Psoriasis (PS). Objectives To evaluate the effectiveness and safety of CT-P13 under routine care in Republic of Korea. Methods This observational study included both biologic naïve patients (Naïve group) and patients who switched from other anti-tumor necrosis factor (TNF)s to CT-P13 (Switch group). Effectiveness were evaluated based on remission (DAS28≤2.6 in RA, BASDAI<3 in AS and absence of swollen and tender joint counts in PsA), and response (BASDAI 20/50/70 in AS and PASI 50/75 in PS). Adverse events (AEs) were collected over 6 month period. Results Total 940 patients (400 with RA, 531 with AS, 3 with PsA and 6 with PS) were registered and 338 (36.0%) patients (108 with RA, 228 with AS, 2 with PS) who switched to CT-P13 were included. The proportion of patients achieving remission was similar between Naïve and Switch groups in both RA and AS during post-baseline visits (Table 1). In RA, the proportion of patients achieving each disease activity category by DAS28 was similar between Naïve and Switch groups (Figure 1). The proportion of patients who achieved BASDAI 20/50/70 response gradually increased from week 6 to week 24 or 30 in Naïve group with AS (Figure 1). Fifty percent of naïve patients with PsA achieved clinical remission. The proportions of both PASI 50 and 75 responses were 50% at Week 22 in Naïve group and were 100% and 50% in Switch group, respectively during post-baseline visits in PS patients. Throughout this study, treatment-emergent adverse events (TEAE) and treatment-emergent serious adverse events (TESAE) were reported as Table 2. Only 11% of patients experienced infection.Table 1. Clinical remission in RA and AS Naïve Switch Baseline Post-baseline Baseline Post-baseline RA DAS28 (ESR) 0/181 (0.0%) 24/182 (13.1%) 0/25 (0.0%) 5/25 (20.0%) DAS28 (CRP) 0/180 (0.0%) 43/179 (24.0%) 2/25 (8.0%) 6/24 (25.0%) AS BASDAI 2/292 (0.7%) 199/292 (68.2%) 112/209 (53.6%) 150/210 (71.4%)Table 2. Summary of safety results n/N (%) RA AS PsA PS TEAE 198/400 (49.5) 183/531 (34.5) 1/3 (33.3) 3/6 (50.0) TEAE related with CT-P13 73/400 (18.3) 64/531 (12.1) 0/3 (0.0) 2/6 (33.3) TESAE 52/400 (13.0) 14/531 (2.6) 0/3 (0.0) 1/6 (16.7) TESAE related with CT-P13 15/400 (3.8) 6/531 (1.1) 0/3 (0.0) 0/6 (0.0) Infusion-related reactions 28/400 (7.0) 11/531 (2.1) 0/3 (0.0) 0/6 (0.0) Conclusions CT-P13 is efficacious and well-tolerated in RA/AS/PsA/PS patients. Efficacy and safety results in patients treated with CT-P13 were clinically consistent to historical data [1,2,3]. Especially, Switch group results showed that CT-P13 provides a useful alternative to other anti-TNFs. References Kobayashi et al (2016). Hetland et al (2005). Hetland et al (2010). Disclosure of Interest D.-W. Kim: None declared, T.-H. Kim: None declared, S. R. Kwon: None declared, E. Y. Lee: None declared, C.-N. Son: None declared, Y. S. Kim: None declared, S. H. Kim: None declared, Y.-B. Park: None declared, J.-W. Hur: None declared, H.-S. Lee: None declared, S. J. Lee Employee of: CELLTRION,Inc., S. H. Lee Employee of: CELLTRION,Inc.

AB0610 Platelet Factor 4 as A Biomarker in Korean Patients with Systemic Sclerosis

Background Systemic sclerosis (SSc) is a complex multi-organ autoimmune disease with chronic and heterogeneous clinical manifestations. There is an unmet need for a new biomarker for early diagnosis and classification of SSc. Recent technical advancements have indicated several biomarkers for SSc; among these, platelet factor 4 (PF4), also known as CXCL4, was suggested by a large-cohort proteomic study 1. PF4 is a chemokine released from activated platelets and is involved in coagulation, inflammation, and angiogenesis, which are influential in SSc pathogenesis. Therefore, PF4 may be an effective biomarker for SSc. Objectives To investigate the efficacy of PF4 as a biomarker for the diagnosis, activity and severity of patients with SSc. Methods Thirty-nine SSc patients (36 female and 3 male; mean age, 58.8±10.42 years; mean disease duration, 7.15±3.92 years; 11 diffuse cutaneous SSc cases and 28 limited cutaneous SSc cases) and 30 healthy controls (HC; 25 female and 5 male; mean age, 46.43±14.43 years) were enrolled. To estimate the circulating PF4 level, levels of platelet poor plasma (PPP) PF4 as well as serum PF4 were measured using an ELISA kit (R&D, Minneapolis, USA). SSc patients were divided into 2 subgroups according to disease activity and based on the presence/absence of interstitial lung disease (ILD), pulmonary hypertension, digital ulcers, and autoantibodies (anti-centromere Ab and anti-Scl70 Ab). Differences between SSc and HC groups were compared by Students t-test, and the subgroups were compared using the Mann-Whitney test. Predictive values of serum PF4 and PPP PF4 for SSc diagnosis were evaluated by the area under the receiver operating characteristic curve (AUROC). Results Serum PF4 levels of SSc were lower than those of HC (SSc, 5143.3±1777.5 ng/mL; HC, 5927.4±1348.5 ng/mL; p =0.048) but no significant differences were observed PPP PF4 levels (SSc, 407.2±486.6 ng/mL; HC, 297.3±141.5 ng/mL; p =0.187) between SSc patients and controls. Moreover, no significant differences were observed between active and inactive SSc subgroups and between subgroups with/without ILD, pulmonary hypertension, digital ulcers, and autoantibodies. The AUROC for serum PF4 and PPP PF4 levels was 0.628 (0.497–0.76, cuff of value 3998.5 ng/mL) and 0.491 (0.367–0.65, cuff of value 511.1 ng/mL), respectively. Conclusions In Korean patients with SSc, both serum PF4 and PPP PF4 levels are not efficient biomarkers for SSc diagnosis and do not appear to be associated with clinical activity and severity. References van Roon JA, Tesselaar K, Radstake TR. Proteome-wide analysis and CXCL4 in systemic sclerosis. N Engl J Med. 2014;370(16):1563–4. Disclosure of Interest None declared

SAT0199 Nmr-Based Metabolomic Analysis for The Diagnosis of Systemic Sclerosis

Background Systemic sclerosis (SSc) is a complex multi-organ autoimmune disease that is caused by inflammation, vasculopathy and fibrosis. Clinical heterogeneity, unpredictable course, high mortality and resistance to treatment make physicians still frustrated. Recently, there are unmet needs of useful biomarkers for diagnosis, disease activity and severity of SSc. Metabolomics is expected to be a useful tool for the identification of biomarkers and new therapeutic targets. Several researchers have applied metabolomics to autoimmune diseases such as systemic lupus erythematosus, and rheumatoid arthritis. Objectives To identify the biomarker candidates for the diagnosis of SSc using metabolomic analysis. Methods Fifty-five patients (48 females (87%); mean age 59.30 ± 11.44 years; disease duration 6.92 ± 4.36 years; 11 diffuse cutaneous SSc, 44 limited cutaneous SSc) and thirty age, gender matched healthy controls (HCs) were enrolled. Serum samples after 8 h of fasting were stored at -80° and analysed using nuclear magnetic resonance (NMR)-based metabolomics. Results Multivariate analysis showed metabolic differences between SSc and HCs using partial least squares discrimination analysis (PLS-DA: R2Y=0.654, Q2=0.482) and orthogonal partial least squares discrimination analysis (OPLS-DA: R2Y=0.83, Q2=0.674) (Figure 1). We identified nine discriminatory metabolites (p<0.05): isopropanol, lactate, 2-oxoisocaproate, glucose, and formate were increased and pyruvate, glutamate, methylguanidine, and methanol were decreased in SSc compared with those in the HCs. Using these metabolites for diagnosis of SSc, sensitivity was 96.36% and specificity was 80% by Leave-one-out analysis.Figure 1. PLS-DA and OPLS-DA plots based on NMR analysis of systemic sclerosis (white dots) and healthy controls (black square). PLS-DA: partial least squares discrimination analysis, OPLS-DA: orthogonal partial least squares discrimination analysis. Conclusions There are considerable differences in the serum metabolomic characteristics between SSc and HCs. We expect that metabolomic analysis can be a useful tool for identification of potential diagnostic biomarkers of SSc. Disclosure of Interest None declared

FRI0533 The Diagnostic Performance of Post-Contrast 3-D Ultrashort Echo Time Sequence of Sacroiliitis in Patients with Axial Spondyloarthropathy Comparing with Conventional Post-Contrast Fat Suppressed T1 Weighted Sequence

Background Axial spondyloarthropathies (axSpA) are chronic inflammatory diseases affecting the sacroiliac joint, spine, peripheral joint, and entheses. Entheses are emphasized as one of the primary targets of axSpA, but they show little signal on conventional clinical magnetic resonance (MR). Recently, the ultrashort echo time (UTE) sequence has been reported to be useful in detecting a signal from the tissues with short T2 such as the ligaments, periosteum, and cortical bone. Contrast enhancement study of UTE sequence showed increased enhancement as a consequence of angiogenesis in a diseased tendon and fibrocartilage. To our knowledge, no prior study has compared the diagnostic performances of post-contrast 3D UTE and conventional post-contrast fat suppressed T1 weighted sequence (FST1WI) for sacroiliitis in patients with axSpA. Objectives To compare the diagnostic performance of post-contrast 3D UTE and conventional FS1WI for sacroiliitis. Methods Total 16 patients with axSpA (asSpA group: 10 men, 6 women, mean age: 35.56 years [range: 24–52 years], human leukocyte antigen B 27 positivity 81.25%,) and 10 patients with mechanical back pain (control group: 2 men, 8 women, mean age: 58.6 years [range 34–74 years]) were enrolled in this prospective study. All patients underwent oblique coronal short tau inversion recovery sequence (STIR), pre/post contrast fat suppressed (FS) 3D UTE, and post contrast FST1WI. Active inflammation of the sacroiliac joint was quantitatively analyzed and scored on post-contrast FS 3D UTE and post contrast FST1WI for inflammatory findings, such as osteitis, synovitis, capsulitis, and enthesitis, by two musculoskeletal radiologists with a consensus. The score per active inflammatory finding of 3D UTE and post contrast FST1WI was compared between axSpA group and control group using Wilcoxon rank test. Results The axSpA group showed higher scores for osteitis and synovitis on both post-contrast FS 3D UTE (P =0.018, 0.025, respectively) and post-contrast FST1WI (P =0.003, 0.005, respectively) and for enthesitis on post-contrast FS 3D UTE with a statistical significance (P =0.004). Post-contrast FS 3D UTE showed statistically significant lower scores for all inflammatory findings than enhanced FS T1 WI sequences did (P <0.05).Figure 1. Oblique coronal image of the SI joint of a 23-year-old man with ankylosing spondylitis. Bone marrow edema (black arrow) is better visualized on FST1WI (A). However, the erosions (white arrow) and synovial enhancement (white dashed arrow) are more clearly visualized on FS 3D UTE with and without enhancement (B,C). Conclusions Post contrast 3D UTE can differentiate axSpA and mechanical back pain, especially when considering enthesitis. Although it showed slightly lower diagnostic performance for the active inflammatory finding than post contrast FST1WI did, post contrast 3D UTE might play a supplementary diagnostic role for early diagnosis of axSpA. Disclosure of Interest K. H. Jung: None declared, Y. J. Kim: None declared, W. Park: None declared, M. J. Lim: None declared, M. Carl Employee of: GE Healthcare, D. E. Kim Employee of: GE healthcare, M. Hwang Employee of: GE Healthcare, J. G. Cha: None declared, S. Kwon: None declared

OP0207 The Relationship Among the Inflammation, Osteoblast Activity, and Adipogenesis in Patients with Ankylosing Spondylitis:

Background Many authors tried to elucidate the relationship among the inflammation, osteoblast activity or new bone formation, and adipogenesis in patients with ankylosing spondylitis (AS). But the results were disappointing. Objectives We investigated the relationship among the inflammation, osteoblast activity or new bone formation, and adipogenesis in patients with AS by novel cell culture technique of osteoblast in peripheral blood and other methods. Methods Male sixteen individuals with AS were enrolled. They met modified New York criteria and were candidates for infliximab therapy. Sex and age matched nineteen controls were also recruited. Peripheral blood mononuclear cells were collected and cultured in growth medium. Once cell multi-layering has been observed (about 7 days), cells were transferred to differentiation medium and cultured for 3 weeks. Cells were then fixed and stained with alizarin S stain to detect any calcified nodules. The optical density (OD) of alizarin S was measured for quantitative analysis. We evaluated the numbers, the differences and relationship of 1) the numbers of circulating osteoblast precursors in peripheral blood, 2) the OD of alizarin S red staining of circulating osteoblast precursors, 3) P1NP (total procollagen type 1 N-terminal propeptide), c-terminal telopeptide (CTX), osteocalcin, triglyceride, low density lipoprotein cholesterol (LDL), apolipoprotein A-1, apolipoprotein B, lipoportein (a) with enzyme linked immunosorbent assay (ELISA), 4) erythrocyte sedimentation rate (ESR), c-reactive protein (CRP), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) before and after 14 week infliximab therapy, 5) bone densitometry (BMD) before infliximab therapy in patients with AS. Results The number of osteoblast precursor cells and optic density of alizarin S were decreased after infliximab therapy (p=0.028 for optic density of alizarin S). The serum level of P1NP was decreased after infliximab therapy (p=0.002). The serum level of triglyceride was tend to increased, but that of lipoprotein (a) was decreased (p=0.07, p=0.007 separately). There were positive correlation between the BASDAI and the serum level of triglyceride (r =0.666, p=0.005), ESR and lipoprotein (a) (r =0.594, p=0.015), CRP and CTX (r =0.648, p=0.012), CRP and P1NP (r =0.631, p=0.016); negative correlation between BASDAI and femur total T score of BMD (r = -0.79, p=0.006) before infliximab therapy. They showed positive correlation between the difference of the serum level of LDL and that of osteocalcin (r =0.566, p=0.022), Alizarin S OD and apoprotein B (r =0.943, p=0.005), Alizarin S OD and osteocalcin (r =0.829, p=0.042); negative correlation between the difference of the serum level of LDL and ESR (r = -0.614, p=0.011) before and after infliximab therapy. Conclusions The circulating osteoblasts in peripheral blood and the serum level of P1NP were decreased significantly after 14 weeks of infliximab therapy. This result could be indirect evidence that infliximab therapy appeared to diminish osteoblast activity or new bone formation in patients with AS. There were strong relationship among inflammation, osteoblast activity, and adipogenesis before and after infliximab therapy in patients with AS. Disclosure of Interest S.-R. Kwon Grant/research support from: From Celltrion, Korea, Republic of, W. park: None declared, M.-J. Son: None declared, M.-J. Lim: None declared, K.-H. Jung: None declared