Short-term predictor for COVID-19 severity from a longitudinal multi-omics study for practical application in intensive care units

BACKGROUND

The COVID-19 pandemic challenged the management of technical and human resources in intensive care units (ICU) across the world. Several long-term predictors for COVID-19 disease progression have been discovered. However, predictors to support short-term planning of resources and medication that can be translated to future pandemics are still missing. A workflow was established to identify a predictor for short-term COVID-19 disease progression in the acute phase of intensive care patients to support clinical decision-making.

METHODS

Thirty-two patients with SARS-CoV-2 infection were recruited on admission to the ICU and clinical data collected. During their hospitalization, plasma samples were acquired from each patient on multiple occasions, excepting one patient for which only one time point was possible, and the proteome (Inflammation, Immune Response and Organ Damage panels from Olink® Target 96), metabolome and lipidome (flow injection analysis and liquid chromatography-mass spectrometry) analyzed for each sample. Patient visits were grouped according to changes in disease severity based on their respiratory and organ function, and evaluated using a combination of statistical analysis and machine learning. The resulting short-term predictor from this multi-omics approach was compared to the human assessment of disease progression. Furthermore, the potential markers were compared to the baseline levels of 50 healthy subjects with no known SARS-CoV-2 or other viral infections.

RESULTS

A total of 124 clinical parameters, 271 proteins and 782 unique metabolites and lipids were assessed. The dimensionality of the dataset was reduced, selecting 47 from the 1177 parameters available following down-selection, to build the machine learning model. Subsequently, two proteins (C-C motif chemokine 7 (CCL7) and carbonic anhydrase 14 (CA14)) and one lipid (hexosylceramide 18:2; O2/20:0) were linked to disease progression in the studied SARS-CoV-2 infections. Thus, a predictor delivering the prognosis of an upcoming worsening of the patient's condition up to five days in advance with a reasonable accuracy (79 % three days prior to event, 84 % four to five days prior to event) was found. Interestingly, the predictor's performance was complementary to the clinicians' capabilities to foresee a worsening of a patient.

CONCLUSION

This study presents a workflow to identify omics-based biomarkers to support clinical decision-making and resource management in the ICU. This was successfully applied to develop a short-term predictor for aggravation of COVID-19 symptoms. The applied methods can be adapted for future small cohort studies.

Machine learning identifies right index finger tenderness as key signal of DAS28-CRP based psoriatic arthritis activity

Psoriatic arthritis (PsA) is a chronic inflammatory systemic disease whose activity is often assessed using the Disease Activity Score 28 (DAS28-CRP). The present study was designed to investigate the significance of individual components within the score for PsA activity. A cohort of 80 PsA patients (44 women and 36 men, aged 56.3 ± 12 years) with a range of disease activity from remission to moderate was analyzed using unsupervised and supervised methods applied to the DAS28-CRP components. Machine learning-based permutation importance identified tenderness in the metacarpophalangeal joint of the right index finger as the most informative item of the DAS28-CRP for PsA activity staging. This symptom alone allowed a machine learned (random forests) classifier to identify PsA remission with 67% balanced accuracy in new cases. Projection of the DAS28-CRP data onto an emergent self-organizing map of artificial neurons identified outliers, which following augmentation of group sizes by emergent self-organizing maps based generative artificial intelligence (AI) could be defined as subgroups particularly characterized by either tenderness or swelling of specific joints. AI-assisted re-evaluation of the DAS28-CRP for PsA has narrowed the score items to a most relevant symptom, and generative AI has been useful for identifying and characterizing small subgroups of patients whose symptom patterns differ from the majority. These findings represent an important step toward precision medicine that can address outliers.

The role of antidrug antibodies in ustekinumab therapy and the impact of methotrexate

OBJECTIVE

We investigated the impact of concomitant MTX on ustekinumab (UST) levels and antidrug antibody (ADA) formation in PsA and evaluated consequences in pharmacodynamics and pharmacokinetics.

METHODS

We conducted a post-hoc analysis on 112 PsA serum samples of subjects treated with open-label UST and either concomitant MTX (UST/MTX, n = 58) or placebo (UST/pbo, n = 54) obtained in a randomized (1:1), double-blind, multicentre trial. A validated antibody-binding-based multitiered testing was used to detect ADA and ADA with neutralizing capacity (nADA). The impact of MTX on UST immunogenicity was analysed by comparison of UST/pbo with UST/MTX cohorts at different time points. Patient- and disease-related predispositions for ADA formation were investigated with multiple linear regression analysis. Immunogenicity impact on pharmacokinetics, safety and efficacy was determined by cohort comparison between patients with and without ADA formation.

RESULTS

Over 52 weeks, 11 UST/pbo- and 19 UST/MTX-treated patients developed ADA (P > 0.05). In the UST/pbo cohort, the visit-dependent UST levels were in the range of 0.047 (0.05) -0.110 (0.07) µg/ml overall, and 0.037 (0.04)-0.091 (0.08) µg/ml in ADA-confirmed subjects. In UST/MTX-treated patients, the UST levels exhibited an intervisit variation in the range of 0.0502 (0.04)-0.106 (0.07) µg/ml overall and 0.029 (0.03)-0.097 (0.07) µg/ml in ADA positive subjects (P > 0.05). At week 52, ADA-confirmed patients did not differ significantly (P > 0.05) in safety or clinical outcomes from ADA-negative patients.

CONCLUSION

Concomitant MTX had no significant impact on UST immunogenicity. Furthermore, ADA formation was not associated with impairments in UST safety, efficacy or trough levels.

TRIAL REGISTRATION

ClinicalTrials.gov, https://clinicaltrials.gov, NCT03148860.

Combining seeded region growing and k-nearest neighbours for the segmentation of routinely acquired spatio-temporal image data

PURPOSE

The acquisition conditions of medical imaging are often precisely defined, leading to a high homogeneity among different data sets. Nonetheless, outliers or artefacts still appear and need to be reliably detected to ensure a reliable diagnosis. Thus, the algorithms need to handle small sample sizes especially, when working with domain specific imaging modalities.

METHODS

In this work, we suggest a pipeline for the detection and segmentation of light pollution in near-infrared fluorescence optical imaging (NIR-FOI), based on a small sample size. NIR-FOI produces spatio-temporal data with two spatial and one temporal dimension. To calculate a two-dimensional light pollution map for the entire image stack, we combine region growing and k-nearest neighbours (kNN), which classifies pixels into fore- and background by its entire temporal component. Thus, decision-making on reduced data is omitted.

RESULTS

We achieved a [Formula: see text] score of 0.99 for classifying a data set as light polluted or pollution-free. Additionally, we reached a total [Formula: see text] score of 0.90 for detecting regions of interest within the polluted data sets. Finally, an average Dice's coefficient measuring the segmentation performance over all polluted data sets of 0.80 was accomplished.

CONCLUSIONS

A Dice's coefficient of 0.80 for the area segmentation does not seem perfect. However, there are two main factors, besides true prediction errors, lowering the score: Segmentation mistakes on small areas lead to a rapid decrease in the score and labelling errors due to complex data. However, in combination with the light-polluted data set and pollution area detection, these results can be considered successful and play a key role in our general goal: Exploiting NIR-FOI for the early detection of arthritis within hand joints.

GWAS meta-analysis of psoriasis identifies new susceptibility alleles impacting disease mechanisms and therapeutic targets

Psoriasis is a common, debilitating immune-mediated skin disease. Genetic studies have identified biological mechanisms of psoriasis risk, including those targeted by effective therapies. However, the genetic liability to psoriasis is not fully explained by variation at robustly identified risk loci. To move towards a saturation map of psoriasis susceptibility we meta-analysed 18 GWAS comprising 36,466 cases and 458,078 controls and identified 109 distinct psoriasis susceptibility loci, including 45 that have not been previously reported. These include susceptibility variants at loci in which the therapeutic targets IL17RA and AHR are encoded, and deleterious coding variants supporting potential new drug targets (including in STAP2, CPVL and POU2F3). We conducted a transcriptome-wide association study to identify regulatory effects of psoriasis susceptibility variants and cross-referenced these against single cell expression profiles in psoriasis-affected skin, highlighting roles for the transcriptional regulation of haematopoietic cell development and epigenetic modulation of interferon signalling in psoriasis pathobiology.

Pre-analytical sample handling standardization for reliable measurement of metabolites and lipids in LC-MS-based clinical research

The emerging disciplines of lipidomics and metabolomics show great potential for the discovery of diagnostic biomarkers, but appropriate pre-analytical sample-handling procedures are critical because several analytes are prone to ex vivo distortions during sample collection. To test how the intermediate storage temperature and storage period of plasma samples from K3EDTA whole-blood collection tubes affect analyte concentrations, we assessed samples from non-fasting healthy volunteers (n = 9) for a broad spectrum of metabolites, including lipids and lipid mediators, using a well-established LC-MS-based platform. We used a fold change-based approach as a relative measure of analyte stability to evaluate 489 analytes, employing a combination of targeted LC-MS/MS and LC-HRMS screening. The concentrations of many analytes were found to be reliable, often justifying less strict sample handling; however, certain analytes were unstable, supporting the need for meticulous processing. We make four data-driven recommendations for sample-handling protocols with varying degrees of stringency, based on the maximum number of analytes and the feasibility of routine clinical implementation. These protocols also enable the simple evaluation of biomarker candidates based on their analyte-specific vulnerability to ex vivo distortions. In summary, pre-analytical sample handling has a major effect on the suitability of certain metabolites as biomarkers, including several lipids and lipid mediators. Our sample-handling recommendations will increase the reliability and quality of samples when such metabolites are necessary for routine clinical diagnosis.

[Psoriatic arthritis : Clinical challenges and pharmaceutical management]

Psoriatic arthritis (PsA) is a systemic immune-mediated inflammatory disease of the musculoskeletal system, which is accompanied by a chronic and progressive course. It is characterized by different clinical manifestations and can severely impair the quality of life and function of patients due to the existing heterogeneity of the manifestations. The (early) diagnosis of PsA and individualized therapeutic management in routine clinical practice are difficult due to the enormous clinical variability. In addition to the appearance of arthritis of the peripheral joints, there can be involvement of the axial skeleton, skin psoriasis, nail psoriasis, enthesitis and dactylitis. The clinical appearance, course of the disease, risk factors and pathophysiological mechanisms of PsA have been extensively researched in recent decades. With the associated better understanding of the disease, new treatment options and goals for effective treatment have also been established.

An objective, automated and robust scoring using fluorescence optical imaging to evaluate changes in micro-vascularisation indicating early arthritis

Fluorescence optical imaging technique (FOI) is a well-established and valid method for visualization of changes in micro vascularization at different organ systems. As increased vascularization is an early feature of joint inflammation, FOI is a promising method to assess arthritis of the hands. But usability of the method is limited to the assessors experience as the measurement of FOI is semi-quantitative using an individual grading system such as the fluorescence optical imaging activity score (FOIAS). The goal of the study was to automatically and thus, objectively analyze the measured fluorescence intensity generated by FOI to evaluate the amount of inflammation of each of the subject’s joints focusing on the distinction between normal joint status or arthritis in psoriatic arthritis patients compared to healthy volunteers. Due to the heterogeneity of the pathophysiological perfusion of the hands, a method to overcome the absoluteness of the data by extracting heatmaps out of the image stacks is developed. To calculate a heatmap for one patient, firstly the time series for each pixel is extracted, which is then represented by a feature value. Secondly, all feature values are clustered. The calculated cluster values represent the relativity between the different pixels and enable a comparison of multiple patients. As a metric to quantify the conspicuousness of a joint a score is calculated based on the extracted cluster values. These steps are repeated for a total number of three features. With this method a tendency towards a classification into unaffected and inflamed joints can be achieved. However, further research is necessary to transform the tendency into a robust classification model.

POS0994 DEVELOPMENT OF AN AUTOMATED ALGORITHM BASED ON METHODS OF ARTIFICIAL INTELLIGENCE TO ASSIST IN THE PREDICTION OF CORRECT REFERRALS OF PSORIATIC ARTHRITIS AND AXIAL SPONDYLOARTHRITIS BY USING PATIENT HISTORY TEXTS

Background

Diagnosis and treatment of PsA and axSpA is often delayed due to missing clear diagnostic criteria and limitations in resources for referral to rheumatologist including high numbers of incorrect referrals. Primary care is usually provided by either general practitioner, dermatologists, or orthopedics. Clinical discriminators with a high specificity for rheumatic conditions include morning stiffness (MST; peripheral or axial, >30min). Artificial intelligence (AI) and natural language processing (NLP) methods offer algorithms for learning systems to recognize disease associated terms and classify clinical phenotypes using large data sets that may support early identification of patients with suspected diagnosis of PsA or axSpA.

Objectives

AI and NLP methods are used to identify patients with typical attributes for inflammation by using morning stiffness as one potential discriminating pattern, which can be detected automatically and might help to prioritize referral for rheumatologist appointments.

Methods

Within a multicentre observational study, patients with visits at the rheumatologist with a suspected diagnosis of PsA or axSpA from the referral primary care provider were recruited. All data on clinical examinations and findings were collected and evaluated by rheumatologists in focus on criteria for diagnosis of PsA/axSpA (gold standard for evaluation). Unstructured text from the patient history was used to extract diagnosis-relevant characteristics. The information extraction algorithms used NLP models to detect expert curated “morning stiffness” (MST) keywords and puts them into a contextualized framework that allows to capture possible negations.

Results

A total of 116 patients were recruited (73 female, 63%) with a median age of 42 (IQR: 34-54). 51 patients were referred as axSpA (44%) and 60 as PsA (52%) by primary care providers. After preselection for PsA and axSpA patients, we observed a 23% rate of referrals without rheumatic diagnosis. Only 7.1% of patients were admitted without signs of MST, 29% with axial MST, 35% with peripheral MST and 28% with both MST types. Average morning stiffness duration was recorded as 35 minutes; patients with a finally confirmed rheumatic diagnosis had a higher average MST duration reported (36 minutes) compared to patients without a confirmed diagnosis. Our AI assisted extraction of MST identified MST in 82.7% of patient history texts. In 75% NLP methods correctly identified the negation of MST symptoms (6 of 8), and 94% of MST was detected when both axial and peripheral joints were affected (30 of 32). Manual inspection of 20 patient history reports where MST was not detected by our automated algorithm revealed that 17 reports did not contain information about MST and three mention unspecific early morning discomfort, without mention of MST.

Conclusion

The high rate of correct detection of MST from patient history text using NLP methods allowed us to assess the potential for NLP models to support automated analysis of patient reports to facilitate intelligent patient referral.

Acknowledgements

We thank the Fraunhofer Excellence Cluster for Immune-Mediated Diseases CIMD for the financial support.

Disclosure of Interests

None declared

POS1094 CORRELATION OF FLUORESCENCE-OPTICAL IMAGING AND PHYSICIAN TJC/SJC ASSESSMENT AND ULTRASOUND IN PSORIASIS PATIENTS WITHOUT ARTHRITIS BUT MUSCULOSKELETAL COMPLAINTS WITHIN THE LAST 6 MONTHS

Background

Psoriasis (PsO) is one of the most common chronic inflammatory skin diseases in Europe. Psoriatic arthritis (PsA) is closely associated to PsO; up to 40% of PsO patients develop PsA. The transition from PsO to PsA includes different stages with unspecific clinical symptoms such as fatigue or musculoskeletal (MSK) symptoms as well as changes in synovial vascularization combined with increased expression of proangiogenic factors [1]. Fluorescence-optical imaging (FOI, [Xiralite]) is an easy-to-use method to detect changes in microvascularisation of the hands.

Objectives

To compare findings from FOI assessment to clinical examination (SJC/TJC) and musculoskeletal ultrasound in patients (MSUS) with non-specific MSK-symptoms and changes in microvascularisation without evidence of clinical active PsA.

Methods

The German multicentre observational XCITING study recruited patients with dermatological confirmed PsO at risk for development of PsA (either nail psoriasis or MSK symptoms such as joint pain or swelling within the last 6 months). Clinical examination (CE; swollen (66) and tender (68) joint count, enthesitis, dactylitis assessment), standardized MSUS and FOI assessment were performed by a qualified rheumatologist at one time point with focus on the question of presence of PsA. Data were analyzed in focus on increased vascularization of MSK structures of both hands as marker of inflammation. The patients at-risk for PsA development but without clinically active PsA (CE negative, FOI positive) were analyzed. Results from CE of joints, MSUS and FOI were compared.

Results

391 PsO patients were recruited for the XCITING study in total. 108 patients (27.6%) were identified as at-risk population (CE negative, FOI positive). Baseline characteristics included a mean age of 51.4 years (SD 11.3), 61.1% female, mean BMI 27.8 kg/m2 (SD 5.2), mean age of onset PsO 30.4 years (SD 17), mean duration of PsO of 16.9 years (SD 14.4), mean PASI 4.3 (SD 5.8) and mean patient’s global disease activity for PsO of 24.4mm (SD 21.1). In 24.1% psoriasis plaques on the hand were documented. Pattern for frequency of scores in FOI, CE and MSUS in the dominant hand were compared (Figure 1). Frequency of swollen joints and synovitis with power Doppler activity (PD Mode) was very low in these patients whereas TJC, detection of synovitis in MSUS and FOI signals were detected in overlapping regions at the hands, showing high correlation. The highest correlation is found between TJC and FOI (Figure 1).

Figure 1.

Overview of frequency of involvement in joints for the different assessments (MSUS, SJC/TJC and FOI)

Conclusion

FOI signals in the hands correlate to the findings of TJC (and B-Mode US) in the clinical examination indicating early stages of MSK inflammation that may result in active PsA development. FOI as standardized and easy-to-use technique might be a suitable tool for early detection of PsA in Psoriasis population. A follow up in these patients will reveal prediction values of the method.

References

[1]Scher, J.U., et al., Preventing psoriatic arthritis: focusing on patients with psoriasis at increased risk of transition. Nat Rev Rheumatol, 2019. 15(3): p. 153-166.

Disclosure of Interests

Michaela Köhm Grant/research support from: Pfizer, Sarah Ohrndorf: None declared, Xenofon Baraliakos: None declared, Konstantin Hallmann Grant/research support from: Pfizer, Susanne Kempinski: None declared, Ann Christina Foldenauer Grant/research support from: Pfizer, Tanja Rossmanith Grant/research support from: Pfizer, Ulf Henkemeier Grant/research support from: Pfizer, Frank Behrens Grant/research support from: Pfizer

POS0079 DOES METHOTREXATE IMPACT USTEKINUMAB IMMUNOGENICITY IN PATIENTS WITH ACTIVE PSORIATIC ARTHRITIS? A POST HOC ANALYSIS OF SAMPLES FROM A RANDOMIZED, PLACEBO-CONTROLLED TRIAL

Background

The formation of antidrug-antibodies (ADA) may reduce treatment efficacy or provoke discontinuation due to adverse reactions. Subsequent alterations in the drugs’ pharmacodynamics, pharmacokinetics, safety, and efficacy are often unpredictable and can impede clinical discourse. Recent studies gave us some insights regarding the role of ADA formation against the monoclonal IL-12/-23 antibody ustekinumab (UST) and the impact of concomitant MTX treatment on immunogenicity in psoriatic arthritis (PsA) patients [1,2]. Valid measurement of ADA, particularly of neutralizing ADA (nADA) is essential to understand UST-associated immunogenicity and may help to predict clinical outcomes.

Objectives

To examine the impact of concomitant MTX on UST-immunogenicity in patients with active psoriatic arthritis (PsA).

Methods

Plasma samples were collected from a randomized controlled trial in patients with active PsA, treated with open UST and placebo-controlled methotrexate over a 52 weeks. We compared samples of 112 patients treated with either UST and MTX (n=58) or UST and placebo (n=54). Plasma samples were obtained shortly before UST injection at weeks 0, 4, 16, 40, and 52.

Immunogenicity testing was performed as described by our group elsewhere [3], in a multitiered manner with ELISA and surface plasmon resonance analysis for the detection and quantification of ADA and UST, respectively. Neutralizing capacity was characterized in a cell-based assay. For statistical analysis, a two-way ANOVA with Sidak correction for multiple comparisons was used.

Results

Over the 52 weeks treatment period, 10 (18 %) of patients in the placebo cohort developed UST-specific ADA with one patient having non-neutralizing ADA, whereas 15 (27 %) subjects in the MTX cohort generated UST-specific ADA with 2 patients having non-neutralizing ADA. The ADA rates and concentrations at the different time points (Figure 1A, B) did not differ significantly between MTX and non-MTX users (p< 0.05). Furthermore, the presence of UST-specific ADA was not associated with decreased UST levels (Figure 1C).

Figure 1.

(A) ADA prevalence (%), (B) mean concentration (µg/ml) of confirmed ADA with 95%confidence interval and (C) mean UST concentration (µg/ml) with 95%confidence intervall in the MTX cohort (UST/MTX; n=58) and placebo cohort (UST/pbo; n=54) overall and with confirmed ADA (ADA+), respectively, at week (w) 0, 4, 16, 40, and 52.

Conclusion

The presented data yielded no statistically significant difference in ADA detection between the two analyzed groups. Our findings suggest that concomitant MTX had no impact on UST immunogenicity in PsA patients.

References

[1]McInnes, I. B. et al. Efficacy and safety of ustekinumab in patients with active psoriatic arthritis: 1 year results of the phase 3, multicentre, double-blind, placebo-controlled PSUMMIT 1 trial. Lancet. 2013;382(9894):780-9.

[2]Leonardi, C.L. et al. Efficacy and safety of ustekinumab, a human interleukin-12/23 monoclonal antibody, in patients with psoriasis: 76-week results from a randomised, double-blind, placebo-controlled trial (PHOENIX 1). Lancet, 371 (2008), pp. 1665-1674.

[3]Mojtahed Poor, S. et al. Immunogenicity assay development and validation for biological therapy as exemplified by ustekinumab. Clin Exp Immunol. 2019;196(2):259-275.

Acknowledgements

Sorwe Mojtahed Poor received research support from the German Society of Rheumatology (DGRh e.V.)

Disclosure of Interests

Sorwe Mojtahed Poor: None declared, Marina Henke: None declared, Thomas Ulshoefer: None declared, Frank Behrens Grant/research support from: Janssen, Michaela Köhm Grant/research support from: Janssen, Harald Burkhardt: None declared, Susanne Schiffmann: None declared

POS1059 EFFICACY OF UST IN ACTIVE PsA IS INDEPENDENT FROM CONCOMITANT MTX USE, EVEN IN PATIENTS WITH MORE SEVERE SKIN PSORIASIS: SUBGROUP ANALYSIS FROM A RANDOMIZED PLACEBO-CONTROLLED INVESTIGATOR INITIATED CLINICAL TRIAL

Background

The use of bDMARDs treatments in patients with psoriatic arthritis (PsA) usually requires treatment failure or intolerance of csDMARD/MTX before initiation. The value of MTX in combination with bDMARDs is still unclear. We designed an investigator-initiated, randomized, placebo-controlled trial (IIT) in active PsA to examine if outcomes of treatment with ustekinumab (UST) in combination with MTX (either newly initiated or ongoing) were different from UST only (+Placebo; PBO). With known efficacy of MTX on skin psoriasis outcomes may differ in patients with or without significant skin involvement of their psoriatic disease.

Objectives

To compare efficacy outcomes in UST+PBO vs UST+MTX in dependency of skin involvement (Body Surface Area [BSA]) at baseline.

Methods

A total of 186 patients with active PsA (defined as TJC≥4, SJC≥4 [68/66 joint count] and DAS28≥3.2) were screened for eligibility. 173 patients were randomized to UST+MTX (new or ongoing) or UST+PBO.

With this post hoc subgroup analysis outcome parameters were compared between patients with or without skin psoriasis > 3 % BSA. Demographic data and disease activity status of arthritis (joint count [TJC/SJC], DAPSA, DAS28), skin (PASI, BSA), HR-QoL (EQ5D, DLQI) and physical function (HAQ) were compared between groups.

Results

BL data were well-balanced between main treatment groups (UST+MTX, n=86; UST+PBO, n=74) including gender (42.5% vs 40.5% female) and mean values for age (49.2 vs 47.2 years), BMI (29.4 vs 28.9 kg/m2), SJC (8 vs 8), TJC (12 vs 12), DAS28-CRP (4.6 vs 4.4), DAPSA (36.7 vs 34.9) and PASI (2.8 vs 2.4. Disease activity remained well-balanced even after dividing groups according to skin involvement ((a) BSA ≤3% and (b) BSA >3%) with a trend of more severe joint involvement (SJC, TJC) in BSA >3% for UST+MTX compared to UST+PBO. At week 24, relative changes in TJC (-62% vs -62%), change in DAS28 and DAPSA were equal in all treatment groups independent from skin involvement (Table 1). Differences between the groups according to skin involvement were seen for relative changes in SJC (BSA >3%: -74.8% UST+MTX vs -84.3% UST+PBO), subject global assessment (SGA), physician global assessment (PGA), DLQI and EQ5D. Highest levels for changes were detected in the UST+PBO group with high skin involvement (BSA >3%).

Table 1.

Outcomes at Week 24 (LOCF)

UST+MTXUST+PBOBSA ≤3%BSA >3%BSA ≤3%BSA >3%n=46n=40n=51n=23TJC68 change from BL-7.83 (SD 10.3)-9.5 (SD 10.3)-8.9 (SD 9.5)-7.3 (SD 7.4)SJC66 change from BL-6.0 (SD 5.4)-7.1 (SD 3.5)-6.5 (SD 6.2)-6.4 (SD 3.8)PASI change from BL+-1.3 (SD 1.9)-8.5 (SD 9.6)-1.5 (SD 2.4)-9.0 (SD 10.7)DAS-28 ESR [mm/hr] change from BL-1.6 (SD 1.1)-1.8 (SD 1.2)-1.7 (SD 1.4)-1.8 (SD 1.1)DAS-28 CRP [mg/l] change to BL-1.5 (SD 1.2)-1.5 (SD 1.3)-1.6 (SD 1.2)- 1.7 (SD 1.1)DAPSA change from BL-17.4 (SD 16.8)-20.8 (SD 13.2)-20.5 (SD 16.6)-20.4 (SD 15.3)HAQ change from BL-0.1 (SD 0.4)-0.2 (SD 0.5)-0.3 (SD 0.3)-0.3 (SD 0.5)DLQI change from BL-3.1 (SD 5.5)-5.5 (SD 8.2)-2.3 (SD 3.3)-6.4 (SD 7.9)EQ5D VAS Health State change from BL6.7 (SD 24.7)11.7 (SD 23.6)8.0 (SD 24.2)21.3 (SD 25.3)

Conclusion

IL12/23 inhibition with UST is an effective treatment for active PsA independent of MTX use. Data from this IIT indicate that additional MTX has no positive impact on UST efficacy for arthritis, skin, HR-QoL and physical function. This independency of UST effect from MTX can also be demonstrated in patients with active skin involvement despite known efficacy of MTX for skin psoriasis.

Acknowledgements

We thank Janssen for support of the study with a research grant.

Disclosure of Interests

Michaela Köhm Speakers bureau: Janssen, Consultant of: Janssen, Grant/research support from: Janssen, Tanja Rossmanith Grant/research support from: Janssen, Ann Christina Foldenauer Grant/research support from: Janssen, Herbert Kellner Speakers bureau: Janssen, Consultant of: Janssen, Uta Kiltz Speakers bureau: Abbvie, Fresenius, Hexal, Janssen, MSD, Novartis, Pfizer, Roche, UCB, Consultant of: AbbVie, Amgen, Biocad, Biogen, Chugai, Eli Lilly, Hexal, Grünenthal, Janssen, MSD, Novartis, Pfizer, Roche, UCB, Grant/research support from: AbbVie, Amgen, Biogen, Fresenius, GSK, Hexal, Novartis, Pfizer, Jürgen Rech Speakers bureau: Abbvie, Biogen, BMS, Chugai, GSK, Lilly, MSD; Novartis, Roche, Sanofi, Sobi, UCB, Consultant of: Biogen, BMS, Chugai, GSK, Lilly, MSD, Novartis, Roche, Sanofi, Sobi, UCB, Grant/research support from: Novartis, Sobi, Gerd Rüdiger Burmester Speakers bureau: Janssen, Consultant of: Janssen, Grant/research support from: Janssen, David M Kofler Speakers bureau: Janssen, Consultant of: Janssen, Grant/research support from: Janssen, Jan Brandt-Juergens Speakers bureau: Janssen, Consultant of: Janssen, Grant/research support from: Janssen, Christin Jonetzko Grant/research support from: Janssen, Harald Burkhardt Speakers bureau: Janssen, Consultant of: Janssen, Grant/research support from: Janssen, Frank Behrens Speakers bureau: Janssen, Consultant of: Janssen, Grant/research support from: Janssen

Sensory testing and topical capsaicin can characterize patients with rheumatoid arthritis

Background and objectives

Our study aimed at examining the long-time inflammatory effects of rheumatoid arthritis (RA) as chronic immune-mediated disease on pain sensation and neuropathy development compared to healthy subjects (HS).

Methods

We used the quantitative sensory testing (QST) protocol of the German Research Network on Neuropathic Pain and Electroencephalography (EEG)–based contact heat evoked potentials (CHEPs) before and after topical capsaicin application. We recruited 16 RA patients in remission or low disease activity state (mean age: 59.38 years [± 10.18]) and 16 healthy subjects (mean age: 56.69 years [± 8.92]).

Results

The application of capsaicin cream on the thigh provoked a stronger effect in HS for both mechanical and heat pain thresholds (MPT and HPT, resp.), according to the area under the receiver operation characteristic (AUROC) (HS: HPT: 0.8965, MPT: 0.7402; RA: HPT: 0.7012, MPT: 0.6113). We observed contrary effects regarding changes in CHEPs (HS: g*max =  − 0.65; RA patients: g*max = 0.72).

Conclusion

As the overall effect of topical capsaicin application was higher in HS for QST, we suggest the existence of a sensitization of TRPV1 channels in RA patients caused by long-time chronical inflammation, despite a lack of clinical signs of inflammation due to adequate treatment. The effect in CHEPs probably uncovers neuropathic symptoms. The effect of topical capsaicin on HPTs and CHEPs can act as a marker for the extent of sensitization and the development of neuropathic symptoms. Further studies are needed to prove if our proposed method can act as a marker for the success of anti-inflammatory treatment.

Key Points • The effect of topical capsaicin may represent the extent of TRPV1 sensitization in rheumatoid arthritis. • The effect of topical capsaicin on the amplitude level of CHEPs can unmask neuropathic symptoms. • The effect of topical capsaicin on CHEPs and HPTs can show the long-term consequences and the treatment success of RA patients in remission.

Therapiestrategien der Psoriasisarthritis

Bestehende Therapieempfehlungen und deren Limitationen In den letzten Jahren haben sich die Basistherapieoptionen für die Behandlung der Psoriasisarthritis deutlich erweitert. Das Sicherheitsprofil der verfügbaren Therapien ist gut untersucht und für die verschiedenen Präparate bekannt. Verschiedene Empfehlungen zur Auswahl und Steuerung der geeigneten Therapie stehen dem Behandler zur Verfügung. Hierbei finden die Empfehlungen der European League Against Rheumatism (EULAR) und der Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) national und international in der Routine Anwendung.

Zugelassene Therapieoptionen zur Behandlung der Psoriasisarthritis csDMARD-Therapien haben im Vergleich zur RA in der PsA-Behandlung eine schlechte Evidenzlage. Für neue Substanzen in den Kategorien tsDMARD und bDMARD liegen höhere Evidenzniveaus vor. Da neue Therapien unterschiedliche Zielstrukturen adressieren, bieten sich zunehmend Chancen der personalisierten und individualisierten Therapieentscheidung. Gerade neue pathophysiologische Erkenntnisse zum Erkrankungsbild und die daraus resultierenden Therapieoptionen, die gezielt spezifische Targets adressieren, bieten Möglichkeiten einer immer differenzierteren und individualisierten medikamentösen Behandlung zur Verbesserung der Versorgung der PsA-Patienten, v. a. mit Fokus auf personalisierte Strategien zur optimalen Behandlung verschiedener Manifestationsformen und -muster.

Randomisierte kontrollierte Studien und deren Relevanz für den Versorgungsalltag Studienendpunkte randomisierter kontrollierter Studien, deren Studiendesign oft aus der rheumatoiden Arthritis entliehen ist, dienen auch aufgrund der großen Heterogenität der Erkrankung kaum als Basis für individuelle Therapieentscheidungen. Ein mehrschrittiges Vorgehen bei der Auswahl eines individualisierten Behandlungsregimes ist wichtig unter Berücksichtigung der klinischen Manifestation, potenzieller Begleiterkrankungen, von Langzeitsicherheitsaspekten, Kontraindikationen, Applikationsformen und nicht zuletzt des Patientenwunschs.

Innovative Imaging Technique for Visualization of Vascularization and Established Methods for Detection of Musculoskeletal Inflammation in Psoriasis Patients

Psoriasis (PsO) is one of the common chronic inflammatory skin diseases. Approximately 3% of the European Caucasian population is affected. Psoriatic arthritis (PsA) is a chronic immune-mediated disease associated with PsO characterized by distinct musculoskeletal inflammation. Due to its heterogeneous clinical manifestations (e.g., oligo- or polyarthritis, enthesitis, dactylitis, and axial inflammation), early diagnosis of PsA is often difficult and delayed. Approximately 30% of PsO patients will develop PsA. The responsible triggers for the transition from PsO only to PsA are currently unclear, and the impacts of different factors (e.g., genetic, environmental) on disease development are currently discussed. There is a high medical need, recently unmet, to specifically detect those patients with an increased risk for the development of clinically evident PsA early to initiate sufficient treatment to inhibit disease progression and avoid structural damage and loss of function or even intercept disease development. Increased neoangiogenesis and enthesial inflammation are hypothesized to be early pathological findings in PsO patients with PsA development. Different disease states describe the transition from PsO to PsA. Two of those phases are of value for early detection of PsA at-risk patients to prevent later development of PsA as changes in biomarker profiles are detectable: the subclinical phase (soluble and imaging biomarkers detectable, no clinical symptoms) and the prodromal phase (imaging biomarkers detectable, unspecific musculoskeletal symptoms such as arthralgia and fatigue). To target the unmet need for early detection of this at-risk population and to identify the subgroup of patients who will transition from PsO to PsA, imaging plays an important role in characterizing patients precisely. Imaging techniques such as ultrasound (US), magnetic resonance imaging (MRI), and computerized tomography (CT) are advanced techniques to detect sensitively inflammatory changes or changes in bone structure. With the use of these techniques, anatomic structures involved in inflammatory processes can be identified. These techniques are complemented by fluorescence optical imaging as a sensitive method for detection of changes in vascularization, especially in longitudinal measures. Moreover, high-resolution peripheral quantitative CT (HR-pQCT) and dynamic contrast-enhanced MRI (DCE-MRI) may give the advantage to identify PsA-related early characteristics in PsO patients reflecting transition phases of the disease.

[Treatment strategies in psoriatic arthritis]

Psoriatic arthritis is a heterogeneous immune-mediated disease that usually involves skin and joints but can also affect entheses and extraarticular structures in the disease course. In addition, associated diseases must be considered when choosing the appropriate therapeutic strategy. Different recommendations for treatment of psoriatic arthritis are available for clinical use. The recommendations of the European League Against Rheumatism (EULAR) and the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) are the two internationally accepted guidelines frequently used to assist therapeutic decisions in clinical practice. New targeted treatment options developed based on a better knowledge of critical pathogenic pathways, will enlarge our armamentarium for optimized pharmacotherapy of psoriatic arthritis and improve personalized patient care.

FRI0360 IMPACT OF METHOTREXATE ON DISEASE PATTERN IN ACTIVE PSORIATIC ARTHRITIS PATIENTS ELIGIBLE FOR A RANDOMIZED CLINICAL TRIAL WITH USTEKINUMAB: COMPARATIVE BASELINE DATA FROM MULTICENTRE INVESTIGATOR-INITIATED MUST TRIAL

Background:

Methotrexate (MTX) is a csDMARD treatment that is initiated as first-line therapy (after NSAID) in active psoriatic arthritis (PsA). Randomized clinical trials mostly require treatment failure or intolerance of csDMARD/MTX therapy before initiation of a biological treatment. We designed an investigator-initiated (IIT) randomised blinded study comparing PsA patients starting open label Ustekinumab (UST) combined with blinded MTX or placebo (PLC). Patients are stratified regarding their previous MTX therapy (continuation or discontinuation of MTX (MTX-pre-treated patients –group A) or newly initiate MTX or continue without MTX (MTX-naïve patients – group B).

Objectives:

To determine disease characteristics of patients with active psoriatic arthritis regarding their skin and musculoskeletal manifestations in dependence of their MTX treatment status.

Methods:

A total of 186 patients with active PsA (defined as TJC ≥4, SJC ≥4 (68/66 joint count) and DAS28 ≥ 3,2) were screened for eligibility. At baseline (BL) 173 patients starting open label UST were randomised to receive either MTX or PLC. At Screening (SCR) and BL, demographic data, PsA and PsO disease activity (joint count (TJC/SJC), enthesitis (LEI), dactylitis (number of digits), PASI, BSA, mtNAPSI), previous medication as well as quality of life (QoL) and function (documented as PRO using DLQI, HAQ and subjects assessment of pain as visual analogue scale (VAS) was documented.

Results:

Our preliminary blinded data export comprised all documented and released data for SCR and BL until Mid-January 2020 - in total 154 randomized patients. Thereof, 78 patients were randomized in group A and 76 in group B. BL characteristics were well balanced between groups (mean age A: 50,7 years vs. 46,4 in B, BMI 29 vs. 29,6 in B). More male were included in B (72% vs. 50 %). In median, patients in A had a disease duration of 2,9 y whereas duration in B was in median 0,3 y. More patients in A had failed previous biological therapy (17 to 6 in B), discontinued due to intolerability or ineffectiveness as allowed for study inclusion. Mean DAS28 was 4,5 (moderate disease activity) for both groups and mean values for SGA, PGA were comparable (SGA: 59,1 vs 54,9 PGA: 61,4 vs. 55.6) reflecting comparable disease activity in peripheral arthritis. Mean LEI was comparable in both groups (A: 1,3 vs B: 1,1). Mean number of digits with dactylitis were slightly higher in B (0,8) than in A (0,2). Overall HAQ showed no differences (1.0 in B vs. 0.8 in A – missing data 45 and 29 resp.) and pain VAS did not differ between groups (A: 54,9 mm vs. 56,6 mm in B). PASI and NAPSI were higher in B at BL than in group A (PASI: 7,2 vs. 3,3, mtNAPSI 5,0 vs. 3,0) and PRO showed a higher skin disease burden experienced by MTX-naïve patients prior randomization: in DLQI more patients on MTX experience “no effect” of their skin disease on QoL (22% vs. 7%) whereas more MTX naïve patients see a “moderate” “large” to “extreme large effect” of their disease on QoL (16%, 11%, 5% in B vs. 10%, 8%, 3% in A).

Conclusion:

Our results give important information about comparability of patient population on MTX or without MTX therapy eligible for biological trials. Despite a comparable disease activity in peripheral arthritis scores, skin disease activity was increased in patients without MTX compared to MTX treated patients. Number of affected digits in dactylitis was lower with MTX, whereas its impact on enthesitis seems to be neglectable.

Disclosure of Interests:

Tanja Rossmanith Grant/research support from: Janssen, BMS, LEO, Pfizer, Michaela Köhm Grant/research support from: Pfizer, Janssen, BMS, LEO, Consultant of: BMS, Pfizer, Speakers bureau: Pfizer, BMS, Janssen, Novartis, Uta Kiltz Grant/research support from: AbbVie, Amgen, Biogen, Novartis, Pfizer, Consultant of: AbbVie, Biocad, Eli Lilly and Company, Grünenthal, Janssen, Novartis, Pfizer, UCB, Speakers bureau: AbbVie, MSD, Novartis, Pfizer, Roche, UCB, Jürgen Rech Consultant of: BMS, Celgene, Novartis, Roche, Chugai, Speakers bureau: AbbVie, Biogen, BMS, Celgene, MSD, Novartis, Roche, Chugai, Pfizer, Lilly, Gerd Rüdiger Burmester Consultant of: AbbVie Inc, Eli Lilly, Gilead, Janssen, Merck, Roche, Pfizer, and UCB Pharma, Speakers bureau: AbbVie Inc, Eli Lilly, Gilead, Janssen, Merck, Roche, Pfizer, and UCB Pharma, Herbert Kellner: None declared, Anita Bulczak-Schadendorf Grant/research support from: Janssen, Ann Christina Foldenauer: None declared, Harald Burkhardt Grant/research support from: Pfizer, Roche, Abbvie, Consultant of: Sanofi, Pfizer, Roche, Abbvie, Boehringer Ingelheim, UCB, Eli Lilly, Chugai, Bristol Myer Scripps, Janssen, and Novartis, Speakers bureau: Sanofi, Pfizer, Roche, Abbvie, Boehringer Ingelheim, UCB, Eli Lilly, Chugai, Bristol Myer Scripps, Janssen, and Novartis, Frank Behrens Grant/research support from: Pfizer, Janssen, Chugai, Celgene, Lilly and Roche, Consultant of: Pfizer, AbbVie, Sanofi, Lilly, Novartis, Genzyme, Boehringer, Janssen, MSD, Celgene, Roche and Chugai

AB1099 EVALUATION OF DIFFERENT FLUORESCENCE-OPTICAL IMAGING (FOI) ASSESSMENT METHODS TO DIFFERENTIATE CLINICAL PSORIATIC ARTHRITIS FROM PSORIASIS

Background:

Psoriasis (Pso) is one of the most common chronic inflammatory skin diseases in Europe. Psoriatic arthritis (PsA) is closely associated to Pso whereas the skin manifestation appears usually years before PsA-related symptoms emerge. Up to 30% of Pso patients develop PsA, but there is no clear correlation between disease duration of Pso and PsA development. In early PsA, changes in synovial vascularisation combined with increased expression of proangiogenic factors appear first. Therefore, imaging biomarkers for detection of changes in vascularisation might be useful for early detection of musculoskeletal disease. Fluorescence-optical imaging (FOI) is an indocyanine green (ICG) tailored method to detect microvascular changes in the hands using ICG kinetics over 360 sec. Different methods for assessment of FOI are available. It has not yet been demonstrated to what extent these methods can be used to differentiate psoriasis from psoriasis arthritis.

Objectives:

To evaluate different reader dependent assessment methods to evaluate FOI in psoriasis and psoriatic arthritis.

Methods:

FOI data (clinical PsA n=137, PsO without PsA n=202) from an observational prospective multicentre trial in Germany was used for manual assessment of the films using two different published assessment methods:(1) FOI activity score (FOIAS) and (2) individual characteristics of ICG kinetics. For (1) FOIAS, the levels of signal enhancement were scored using a scoring system from 0 to 3 (0=no enhancement, 3=strong enhancement) per joint as well as an assessment of the summation picture. (2) Kinetics were determined by joint-related signal enhancements as well as by ICG related flow-on and flow-off behaviour. Time to the first appearance of the signal, the time to the maximum enhancement and the time to the end of the signal were determined.

Results:

By use of (1) FOIAS, the maximum score (overall signals of all joints assessed by FOIAS) showed a significant difference (p=0.0075) between PsA (mean 4.76) and PsO (mean 3.84). (2) Time to global maximum showed no significant difference (PsA mean 91.1 sec vs PsO 92.6 sec). Moreover, the mean time to maximum and clearance of ICG did not differ between the two diseases. The duration of the 3 phases of kinetic (phase 1: flow-in, phase 2: stable, phase 3: clearance) was 52.4 sec, 180.2 sec and 119.8 sec for PsA and 57.6 sec, 186.0 sec and 130.5 sec for PsO with an earlier phase 2 and 3 for PsA by trend. The most frequently affected joints in PsA (affected > 10%): PIP 3 right and PIP 5 right.

Conclusion:

FOI is a sensitive method to detect changes in microvascularisation in the hands. The use of the manual FOIAS is able to differentiate significantly between PsA and PsO patients by comparison of the sum of scores over all joints (maximum score). The assessment of ICG kinetics is limited to discriminate between musculoskeletal and joint disease, differentiation of diseases is only seen by trend. Both methods characterize disease states differently. A combination of both methods might be useful to increase the potential of manual assessment of FOI signals.

Figure 1.

Maximum sum score of FOIAS in PsO and PsA patients (p=0.0075 in two-sided t-test).

Disclosure of Interests:

Luis Haan: None declared, Ulf Henkemeier: None declared, Ann Christina Foldenauer: None declared, Harald Burkhardt Grant/research support from: Pfizer, Roche, Abbvie, Consultant of: Sanofi, Pfizer, Roche, Abbvie, Boehringer Ingelheim, UCB, Eli Lilly, Chugai, Bristol Myer Scripps, Janssen, and Novartis, Speakers bureau: Sanofi, Pfizer, Roche, Abbvie, Boehringer Ingelheim, UCB, Eli Lilly, Chugai, Bristol Myer Scripps, Janssen, and Novartis, Frank Behrens Grant/research support from: Pfizer, Janssen, Chugai, Celgene, Lilly and Roche, Consultant of: Pfizer, AbbVie, Sanofi, Lilly, Novartis, Genzyme, Boehringer, Janssen, MSD, Celgene, Roche and Chugai, Michaela Köhm Grant/research support from: Pfizer, Janssen, BMS, LEO, Consultant of: BMS, Pfizer, Speakers bureau: Pfizer, BMS, Janssen, Novartis

SAT0325 STELLATE BLOCKADE COMBINED TO ILOPROST AS SUPPORTIVE TREATMENT OPTION IMPROVES PAIN AND ISCHAEMIC SYMPTOMS IN PATIENTS WITH SYSTEMIC SCLEROSIS

Background:

Peripheral ischaemia is a common symptom in systemic sclerosis (SSc) patients with risk of development of digital ulcers (DU). For its treatment, intravenous iloprost is the most effective option. Accompanying pain symptoms worsen the ischaemic symptoms, so a combination with anaesthetic procedures may improve ischaemic status and the subjective sensation of raynaud and pain. The aim of this study was to observe the impact of a combined treatment of iloprost with stellate blockade (ILOST) in improvement of ischaemic symptoms compared to iloprost treatment only (ILO).

Objectives:

To evaluate efficacy of the ILOST treatment on changes in vascularisation and sensation of patients with SSc and indication for vasodilatative treatment with Iloprost.

Methods:

Twenty SSc-patients with indication for ILO-treatment (prophylactic or due to digital ulcerations (DU)) will be included in a prospective observational study. Patients will be offered to combine ILO with stellate blockade (ILOST). Beside documentation of disease activity characteristics (mRSS, number of DU, capillary microscopy at baseline, after ILO-treatment and at week 12), patients are assessed using fluorescence-optical imaging (FOI) as innovative method for illustration of changes in microvascularisation and patient reported outcomes (DASH, VAS) at week 12.

Results:

This interims analysis includes the result of the first 11 patients treated. Mean baseline characteristics (age and gender) are well balanced. Iloprost treatment was initiated due to prophylactic treatment to avoid DU in all patients. 100% of the patients in the ILOST-group were diagnosed as limited SSc compared to 60% in the ILO-group (diffuse type with 40%). All patients showed abnormalities in capillary microscopy (ILOST group: 83,3% late pattern 16.7% active pattern; ILO group: 80% late pattern, 20% early pattern). MRSS was low in both groups with 1.8, the disease duration in mean 15.3 years in the ILOST-group compared to 13.2 in the ILO-group, respectively. In both groups, no new DU occurred in the 12-week follow-up. Improvement in VAS pain was reported in 83% of the patients in the ILOST group compared to 60% in the ILO group. DASH improved with a mean of 5.5 points in the ILOST group compared to 3 points in the ILO group. FOI was compared individual at both arms in the ILOST group only. The arm with stellatum blockade showed a pronounced increase of FOI signals of 5% in mean whereas the opposite site showed a decrease of the signal shortly after ILO treatment indicating a pronounced increase of vascularisation in the ILOST treated body site.

Conclusion:

A new treatment approach to improve acute ischaemic symptoms was tested by combining stellate blockade to iloprost treatment. No new DU occurred up to 12 weeks after treatment in all patients of both groups indicating the relevance of iloprost as effective vascular dilatative therapy in SSc. The additional intervention was well tolerated and asked to repeat. Subjective sensation on pain of the hands as well as DASH was improved in the combined group. FOI showed a relevant increase in vascularisation in the blockade arm compared to the opposite site in which signals decreased indicating a stronger effect of the combined treatment for improvement of vascularisation.

Disclosure of Interests:

Franziska Höcketstaller Grant/research support from: Rheumazentrum Rhein-Main, Ulf Henkemeier: None declared, Michael Zimmermann: None declared, Harald Burkhardt Grant/research support from: Pfizer, Roche, Abbvie, Consultant of: Sanofi, Pfizer, Roche, Abbvie, Boehringer Ingelheim, UCB, Eli Lilly, Chugai, Bristol Myer Scripps, Janssen, and Novartis, Speakers bureau: Sanofi, Pfizer, Roche, Abbvie, Boehringer Ingelheim, UCB, Eli Lilly, Chugai, Bristol Myer Scripps, Janssen, and Novartis, Frank Behrens Grant/research support from: Pfizer, Janssen, Chugai, Celgene, Lilly and Roche, Consultant of: Pfizer, AbbVie, Sanofi, Lilly, Novartis, Genzyme, Boehringer, Janssen, MSD, Celgene, Roche and Chugai, Ulrich Drott: None declared, Michaela Köhm Grant/research support from: Pfizer, Janssen, BMS, LEO, Consultant of: BMS, Pfizer, Speakers bureau: Pfizer, BMS, Janssen, Novartis

AB1138 ASSESSMENT OF FLUORESCENCE-OPTICAL IMAGING TECHNIQUE OF THE HANDS IN PSORIASIS AND PSORIATIC PATIENTS USING AN INNOVATIVE OBJECTIVE METHOD

Background:

Psoriasis (Pso) is one of the most common chronic inflammatory skin diseases in Europe. Psoriatic arthritis (PsA) is closely associated to Pso whereas the skin manifestation appears usually years before PsA-related symptoms emerge. Up to 30% of Pso patients develop PsA, biomarkers for its early detection are of major importance. In early PsA, changes in synovial vascularisation appear first. Imaging biomarkers for detection of changes in vascularisation might be useful for early detection of musculoskeletal disease. Fluorescence-optical imaging (FOI) is a new method to detect changes in microvascularisation of the hands. Each collected data set of the FOI system contains 360 images representing a time progression of the indocyanine green (ICG) distribution.

Objectives:

To evaluate a reader-independent assessment method for evaluation of FOI in patients with PsO and PsA.

Methods:

A prospective study including patients with dermatological confirmed skin PsO was performed. 411 patients were included from German dermatology units without PsA diagnosis but potential risk for its development. Clinical examination (CE) was performed by a qualified rheumatologist. For a reader independent evaluation of the FOI images an objective joint-based scoring method was developed. For this method, the joint areas are defined by image segmentation and scored based on generated heatmaps. To calculate a heatmap indicating conspicuous joints from a data set containing 360 images, each pixel is converted to a time series containing 360 values. From this time series, three independent values (features) are extracted: amplitude, average value and maximal slope. Thus, each pixel is reduced to three different feature values. After the three features are determined for each pixel, k-means clustering is performed on each feature. The numbers of centroids (k) are set to 3, 5, 7 and 9. 12 heatmaps (3 features à 4 ks) are calculated, which results in 12 scores for each joint as well. The clusters are then sorted dependent on their centroid value and coloured accordingly to a predefined heatmap colour palette. To finally score each joint, the pixels in the segmented joint area and their assigned cluster are summed and normalized by the area’s amount of pixels and k.

Results:

271 of the patients were investigated by the newly developed method and compared with the CE scoring. 6426 joints were labeled as healthy whereas 1162 joints were either labeled as swollen, tender or both. The result over all investigated patients for k = 9 is summed in table 1. It is observable that every average and median healthy value is lower than the corresponding affected value.

Table 1.

Resulting scores for k = 9 for all 271 patients.

Feature Statistic valueAmplitudeMeanSlopeHealthyAffectedHealthyAffectedHealthyAffectedAverage0.5030.5280.4860.5090.3950.414Median0.4960.5320.4820.5050.3890.415

Conclusion:

FOI is an innovative method that detects early changes in vascularization of the hands. So, this method can be useful in early detection of arthritis especially in risk populations such as PsO patients. The results of the objective scoring method show that a clear distinction between healthy and affected joints is possible with the average scores as well as the median values. However, if the range of the scores is considered, the overlap between healthy and affected is not neglectable. Thus, the current scoring system can be used as an indicator but not as a single classification marker. Nevertheless, the research at hand has shown the expected outcome and motivates further development on the heatmap approach.

Disclosure of Interests:

Lukas Zerweck: None declared, Ulf Henkemeier: None declared, Phuong-Ha Nguyen: None declared, Tanja Rossmanith Grant/research support from: Janssen, BMS, LEO, Pfizer, Andreas Pippow: None declared, Harald Burkhardt Grant/research support from: Pfizer, Roche, Abbvie, Consultant of: Sanofi, Pfizer, Roche, Abbvie, Boehringer Ingelheim, UCB, Eli Lilly, Chugai, Bristol Myer Scripps, Janssen, and Novartis, Speakers bureau: Sanofi, Pfizer, Roche, Abbvie, Boehringer Ingelheim, UCB, Eli Lilly, Chugai, Bristol Myer Scripps, Janssen, and Novartis, Frank Behrens Grant/research support from: Pfizer, Janssen, Chugai, Celgene, Lilly and Roche, Consultant of: Pfizer, AbbVie, Sanofi, Lilly, Novartis, Genzyme, Boehringer, Janssen, MSD, Celgene, Roche and Chugai, Michaela Köhm Grant/research support from: Pfizer, Janssen, BMS, LEO, Consultant of: BMS, Pfizer, Speakers bureau: Pfizer, BMS, Janssen, Novartis

SAT0032 INCIDENCE OF RHEUMATOID ARTHRITIS IN PATIENTS WITH NEW ONSET OF MUSCULOSKELETAL SYMPTOMS AND ANTI-CPP POSITIVITY COMPARED TO ANTI-CPP NEGATIVE PATIENTS

Background:

Rheumatoid Arthritis (RA) is a chronic inflammatory joint disease. Strategies for its early detection and diagnosis are of high importance as prompt treatment improves clinical and structural outcome. Autoantibodies against cyclic citrullinated proteins (anti-CCP) have been associated with RA-development. Non-specific musculoskeletal (nsMSK) symptoms are often described prior to RA development. Majority of patients with nsMSK symptoms present to their general practice (GP) first. Studies of early arthritis cohorts have shown that many early arthritis patients cannot be accurately diagnosed at their first visit and are often referred as undifferentiated arthritis patients.

Objectives:

To evaluate the incidence of anti-CCP positivity in patients with new onset of nsMSK symptoms and the incidence of RA in these patients over a 3-year follow-up period compared to anti-CPP negative patients.

Methods:

In this prospective study (PANORA), 978 patients with new onset of nsMSK symptoms were included in 77 GP sites in Germany. Patients with a positive anti-CCP rapid-test (CCPoint®) were referred to Rheumatology Department (RD) for rheumatological assessment, RA-evaluation and an anti-CCP validation test (ELISA). ELISA anti-CCP positive patients without RA were monitored every 6 months for a total follow-up of 36 months or until RA-diagnosis. Patients with a negative anti-CPP result (CCPoint® or ELISA) are followed up with a questionnaire after 1 and 3 y.

Results:

From 978 included patients, 105 (10.7%) were CCPoint® positive. 96 were tested with ELISA and 27 (28.1%) were confirmed anti-CCP positive. 9 (33.3%) were diagnosed with RA at the first RD visit (study visit 2); 4 further patients were diagnosed with RA during the follow-up (FU) period so far. Overall, 48.1% of ELISA-positive (ELISA+) patients were diagnosed with RA up to now; 11 ELISA+ patients are still in the FU period of the study. Of the 868 CCPoint® negative patients, currently, 282 have filled out a 1-year FU questionnaire; 3.5% of those reported a RA diagnosis (Table 1). As expected, clinical parameters at V2 (e.g. CRP, swollen and tender joint count) were worse in the ELISA+/RA+ group compared to the ELISA-/RA- group, but no obvious differences were detected between ELISA+ patients who were diagnosed with RA during the FU period (after V2) and ELISA-/RA- patients

Table 1.

Number and percentage of patients with a RA diagnosis

Anti-CCP statusVisit 2Follow-up*TotalPoint-of-Care Test --3.5% (10 of 282)#3.5% (10 of 282)#Point-of-Care Test + / ELISA -2.9% (2 of 69)0% (0 of 34)#2.9% (2 of 69)Point-of-Care Test + / ELISA +33.3% (9 of 27)14.8% (4 of 27)48.1% (13 of 27)$

* 1 year-questionnaire for Point-of-Care Test and ELISA negative patients or every 6 months follow-up for ELISA positive patients;#Patient-reported;$11 patients are still in the follow-up phase of the study

Conclusion:

Currently, 48.1% of anti-CCP+ (ELISA) patients have received a RA diagnosis, whereas 3.5% of the anti-CCP- (CCPoint®) received a RA diagnosis (patient reported), which underlines, that anti-CCP can be used as a marker to identify high-risk patients in GP setting. While clinical parameters are correlated with the diagnosis of RA, they are not suited for predicting future RA development alone. Anti-CCP, possibly in combination with additional parameters imaging, might increase the likelihood to early diagnose or predict RA development.

Figure 1.

Study overview: Patient distribution depending on anti-CCP results and RA diagnosis.

Disclosure of Interests:

Stephanie Dauth Grant/research support from: BMS, Michaela Köhm Grant/research support from: Pfizer, Janssen, BMS, LEO, Consultant of: BMS, Pfizer, Speakers bureau: Pfizer, BMS, Janssen, Novartis, Timm Oberwahrenbrock Grant/research support from: BMS, Ulf Henkemeier: None declared, Tanja Rossmanith Grant/research support from: Janssen, BMS, LEO, Pfizer, Karola Mergenthal Grant/research support from: BMS, Juliana J. Petersen Grant/research support from: BMS, Harald Burkhardt Grant/research support from: Pfizer, Roche, Abbvie, Consultant of: Sanofi, Pfizer, Roche, Abbvie, Boehringer Ingelheim, UCB, Eli Lilly, Chugai, Bristol Myer Scripps, Janssen, and Novartis, Speakers bureau: Sanofi, Pfizer, Roche, Abbvie, Boehringer Ingelheim, UCB, Eli Lilly, Chugai, Bristol Myer Scripps, Janssen, and Novartis, Frank Behrens Grant/research support from: Pfizer, Janssen, Chugai, Celgene, Lilly and Roche, Consultant of: Pfizer, AbbVie, Sanofi, Lilly, Novartis, Genzyme, Boehringer, Janssen, MSD, Celgene, Roche and Chugai

AB1111 PREDICTIVE VALUE OF FLUORESCENCE-OPTICAL IMAGING TECHNIQUE IN DETECTION OF PSORIATIC ARTHRITIS IN PSORIASIS PATIENTS

Background:

Psoriasis (Pso) is one of the most common chronic inflammatory skin diseases in Europe. Psoriatic arthritis (PsA) is closely associated to Pso whereas the skin manifestation appears usually years before PsA-related symptoms emerge. Up to 30% of Pso patients develop PsA, but there is no clear correlation between disease duration of Pso and PsA development. Therefore, biomarkers for its early detection are of major importance. In early PsA, changes in synovial vascularisation combined with increased expression of proangiogenic factors appear first. Therefore, imaging biomarkers for detection of changes in vascularisation might be useful for early detection of musculoskeletal disease. Fluorescence-optical imaging (FOI) is a new method to detect changes in microvascularisation of the hands.

Objectives:

To determine the number of positive PsA diagnosis within a 24 month follow-up period in PsO only patients with subclinical MSK-inflammation detected in FOI.

Methods:

Sensitivity of FOI for detection of subclinical signs of musculoskeletal inflammation as biomarker for early PsA was observed in a prospective, multicentre study (XCITING) including patients with dermatological confirmed skin psoriasis. 411 patients were included from dermatology care units across Germany without diagnosis of PsA but potential risk factors for its development (nail psoriasis and/or joint pain or swelling within the last 6 months). Clinical examination (CE; swollen (66) and tender (68) joint count, enthesitis, dactylitis assessment) and standardised ultrasound (US) assessment was performed by a qualified rheumatologist to assess musculoskeletal inflammation. FOI was performed additionally. Data was analysed in focus on increased vascularisation of musculoskeletal structures as inflammatory markers. In case of discrepant results (positive FOI and negative CE and US), MRI was performed to prove the findings. In case of MRI negativity, a follow-up period of 24-months was performed including FOI, CE, US and MRI assessment.

Results:

83 of the 411 patients of the cohort were negative in all assessments (Pso only), 136 of the 411 patients were classified as PsA by rheumatologic assessments. 119 patients showed subclinical signs of musculoskeletal inflammation in the central reading of FOI, whereas CE and US were negative. In 37,5% of those patients, subclinical inflammation was confirmed by MRI assessment. 22 patients of the cohort without MRI positivity were willing to be followed up until month 24. 5 (7.5%) patients developed a clinical PsA until month 24 whereas 7 (10.5%) patients converted to be FOI negative. In 5 patients an additional MRI examination was performed in which one patient showed positive signs for inflammation.

Conclusion:

FOI is an innovative method for measurement of changes in microvascularisation in the hands. 6/22 patients initial only positive in FOI (no clinical signs for PsA, negative US, negative MRI) developed either clinical evident PsA (n=5) or new inflammation in MRI (n=1) during follow-up of 24 months. Therefore, FOI positive signals in PsO patients increase the probability for PsA development.

Figure 1.

Flow Chart of the Follow-up period of the XCITING study.

Disclosure of Interests:

Michaela Köhm Grant/research support from: Pfizer, Janssen, BMS, LEO, Consultant of: BMS, Pfizer, Speakers bureau: Pfizer, BMS, Janssen, Novartis, Sarah Ohrndorf: None declared, Tanja Rossmanith Grant/research support from: Janssen, BMS, LEO, Pfizer, Marina Backhaus Grant/research support from: Pfizer, Gerd Rüdiger Burmester Consultant of: AbbVie Inc, Eli Lilly, Gilead, Janssen, Merck, Roche, Pfizer, and UCB Pharma, Speakers bureau: AbbVie Inc, Eli Lilly, Gilead, Janssen, Merck, Roche, Pfizer, and UCB Pharma, Siegfried Wassenberg: None declared, Benjamin Köhler Grant/research support from: Pfizer, Harald Burkhardt Grant/research support from: Pfizer, Roche, Abbvie, Consultant of: Sanofi, Pfizer, Roche, Abbvie, Boehringer Ingelheim, UCB, Eli Lilly, Chugai, Bristol Myer Scripps, Janssen, and Novartis, Speakers bureau: Sanofi, Pfizer, Roche, Abbvie, Boehringer Ingelheim, UCB, Eli Lilly, Chugai, Bristol Myer Scripps, Janssen, and Novartis, Frank Behrens Grant/research support from: Pfizer, Janssen, Chugai, Celgene, Lilly and Roche, Consultant of: Pfizer, AbbVie, Sanofi, Lilly, Novartis, Genzyme, Boehringer, Janssen, MSD, Celgene, Roche and Chugai

AB1289-HPR PERCEPTION OF THE VALUE OF DRUGS ON DIFFERENT MANIFESTATIONS OF PSORIATIC ARTHRITIS BASED ON A MULTI-STAGE EXPERT OPINION SURVEY

Background:

Patients with psoriatic arthritis (PsA) present with heterogeneous clinical phenotypes, which includes different clinical manifestations such as peripheral arthritis, axial disease, dactylitis, enthesitis, and skin and nail psoriasis. Many drugs for treatment of PsA are available for individualised treatment strategies but robust evidence is available for peripheral arthritis only as primary endpoint of RCTs.

Objectives:

To evaluate perception of German physicians on the value of current PsA treatments on different clinical PsA manifestations.

Methods:

In a face-to-face meeting, 8 German physicians (dermatology, rheumatology), specialised in PsA research/patient care, proposed initial scores for the effect size of current PsA drugs on different PsA manifestations based on knowledge of study data and personal experience in use of the drugs. The ability to achieve a consensus of the proposed efficacy scores was explored by applying an online survey among a cohort of PsA experienced physicians. Finally, a second online survey evaluated how a larger group of physicians personally estimate the drug effect sizes on different PsA manifestations.

Results:

Table 1 summarises the efficacy scores proposed by the initial expert group. In the first online survey 25 treating physicians were invited to participate, 14 (56%) of whom completed the survey. An agreement rate of over 65% of the participants was archived for 49 (68%) of the 72 proposed efficacy scores (Table 1). The consensus was especially high for the group of biological disease-modifying antirheumatic drugs (bDMARDs), except for etanercept and abatacept. However, the second survey (16 (39%) participants out of 41 invited physicians) revealed that the experience with the treatment using abatacept was low (4 / 16 (25%)) or non-existing (3 /16 (18.8%)) and several manifestations could not be estimated (Figure 1). Distribution of answers were broad for etanercept in general and for particular drug-manifestation combinations (e.g. effect of ustekinumab on axial disease).

Table 1.

Efficacy scores proposed by a PsA expert group and consensus achieved by an online survey among PsA treating physicians Efficacy scores for different drugs and manifestations range from 0 (no effect) to 5 (maximal effect). Green fields indicate, that at least 65% of the survey participants agreed on the proposed efficacy score.

Peripheral arthritisAxial diseaseEnthesitisDactylitisSkin diseaseNail diseaseMethotrexat2.50012.51.5Sulfasalazin100000Leflunomid2.500111Apremilast3132.533Etanercept4443.533.5Infliximab444444Adalimumab444444.5Golimumab444433Certolizumab pegol444444Ustekinumab3.52.54.534.54Secukinumab444454.5Abatacept3.50001.50Figure 1.

Results from an online survey among physicians querying their perception of efficacies of PsA drugs on different manifestations. Therapeutic effectiveness is estimated by the participants on a scale from 0 (no effect) to 5 (maximal effectiveness); NA = no answer. The size of the dots relates to the number of answers given. Red stars indicate the scores proposed by the initial expert group.

Conclusion:

Many treatments are available to be used in PsA. The usage of treatment classes seems to depend on experience level and mode of action. Higher agreement on efficacy in specific diseases manifestation was achieved in the class of biologics whereas the opinion on efficacy of csDMARDs in general is divergent. Strategies are needed to guide physicians with lower level of experience in the use of specific drugs to achieve an optimised patient care level using personalized treatment strategies.

Disclosure of Interests:

Timm Oberwahrenbrock Grant/research support from: BMS, Hannah Tian: None declared, Diamant Thaçi Grant/research support from: Janssen Research & Development, LLC, Klaus Krueger Consultant of: Celgene, Jürgen Wollenhaupt Consultant of: Celgene, Michaela Köhm Grant/research support from: Pfizer, Janssen, BMS, LEO, Consultant of: BMS, Pfizer, Speakers bureau: Pfizer, BMS, Janssen, Novartis, Frank Behrens Grant/research support from: Pfizer, Janssen, Chugai, Celgene, Lilly and Roche, Consultant of: Pfizer, AbbVie, Sanofi, Lilly, Novartis, Genzyme, Boehringer, Janssen, MSD, Celgene, Roche and Chugai

Genetic variants in FBLIM1 gene do not contribute to SAPHO syndrome and chronic recurrent multifocal osteomyelitis in typical patient groups

Background

Syndrome of synovitis acne pustulosis hyperostosis osteitis (SAPHO) and chronic recurrent multifocal osteomyelitis (CRMO) present two diseases of a dermatologic and rheumatologic spectrum that are variable in manifestation und therapeutic response. Genetic risk factors have long been assumed in both diseases, but no single reliable factor has been identified yet. Therefore, we aimed to clinically characterize a patient group with syndrome of synovitis acne pustulosis hyperostosis osteitis (SAPHO) (n = 47) and chronic recurrent multifocal osteomyelitis (CRMO)/ chronic non-bacterial osteomyelitis (CNO) (n = 9) and analyze a CRMO candidate gene.

Methods

Clinical data of all patients were collected and assessed for different combinations of clinical symptoms. SAPHO patients were grouped into categories according to the acronym; disease-contribution by pathogens was evaluated. We sequenced coding exons of FBLIM1.

Results

Palmoplantar pustular psoriasis (PPP) was the most common skin manifestation in CRMO/CNO and SAPHO patients; most SAPHO patients had sterno-costo-clavicular hyperostosis. The most common clinical category of the acronym was S_PHO (n = 26). Lack of pathogen detection from bone biopsies was more common than microbial isolation. We did not identify autosomal-recessive FBLIM1 variants.

Conclusions

S_PHO is the most common combination of symptoms of its acronym. Genetic analyses of FBLIM1 did not provide evidence that this gene is relevant in our patient group. Our study indicates the need to elucidate SAPHO’s and CRMO/CNO’s pathogenesis.

[Imaging of psoriatic arthritis and aspects of radiographic progression]

Psoriatic arthritis (PsA) is a heterogeneous multifactorial disease with musculoskeletal involvement, which can be manifested as monoarthritis, oligoarthritis or polyarthritis and in some patients can also affect the axial skeleton. The most frequent indications of inflammation are bone marrow edema and enthesitis. The early and differential diagnosis of PsA is a clinical challenge, particularly as a differential diagnosis from other inflammatory or degenerative diseases of joints. Inflammatory joint and tendon alterations in the region of the extremities and the spine can be visualized with high sensitivity by the use of magnetic resonance imaging (MRI), musculoskeletal sonography (US) and fluorescence optical imaging (FOI). The use of MRI has a prognostic value with respect to the further radiographic course of the disease, particularly in the initial stages of the disease. Structural damage can be specifically and also partially demonstrated 3‑dimensionally in peripheral joints and the spine by the use of computed tomography (CT) and conventional X‑ray imaging. High-resolution peripheral quantitative CT (HR-pQCT) in particular, can visualize pathophysiological processes and the morphological consequences even in early stages of the disease. The values of conventional X‑ray diagnostics, CT, MRI, musculoskeletal US and alternative imaging procedures are presented with respect to the diagnostics and prognosis of the progression of patients with PsA.

Aktuelle Therapie der Psoriasisarthritis

Die Psoriasis Arthritis tritt klinisch als heterogene Erkrankung mit phänotypisch sehr variabler Ausprägung auf. Neben der Beteiligung von Haut und Gelenken, manifestiert sich die Erkrankung mit enthesialem, axialem und extra-muskuloskelettalen Erscheinungsbild. Verschiedene Empfehlungen zur Auswahl und Steuerung der geeigneten Therapie stehen zur Behandlung zur Verfügung. Hierbei finden die Empfehlungen der European League Against Rheumatism (EULAR) und die der Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) national und international in der Routine Anwendung. Beide Empfehlungen stehen seit 2016 in der aktuellen Version zur Verfügung, beide werden derzeit aktualisiert, um den umfangreichen Entwicklungen in diesem Indikationsfeld Rechnung zu tragen. Spezielle deutsche Therapieempfehlungen fehlen derzeit noch. Neue Therapieoptionen, die gezielt unterschiedliche Targets adressieren, bieten Möglichkeiten einer differenzierten medikamentösen Behandlung zur Verbesserung der Versorgung der PsA-Patienten, v. a. mit Fokus auf personalisierte Strategien zur optimalen Behandlung verschiedener Manifestationsformen und -muster.

[Treatment of psoriatic arthritis : Are there differential indications?]

Psoriatic arthritis (PsA) is a very heterogeneous immune-mediated disease that usually involves skin and joints but can also affect entheses and extra-articular structures during the disease course. Furthermore, it can also be linked with other associated diseases. Therefore, the individualized selection of an effective and patient-oriented treatment must be carried out taking the extent of various manifestations of the PsA itself and also of other influencing factors into consideration. Various recommendations for selection and control of the suitable treatment of PsA are available for clinical use. The recommendations of the European League Against Rheumatism (EULAR) and the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) are the two recommendations that are frequently used and internationally acknowledged. Both recommendations were updated in 2016. Specific German treatment recommendations are currently missing. In analogy to the treat-to-target strategy for rheumatoid arthritis, at least minimal disease activity (MDA) should be achieved in PsA patients with the use of specific therapeutic interventions if remission as the maximum therapeutic goal cannot be reached. New treatment options, which target different specific molecules, offer possibilities for a more differentiated personalized medicinal treatment for improvement of the care of PsA patients. This particularly applies to a focus on personalized strategies for optimal treatment of various manifestation forms and patterns.

Immunogenicity assay development and validation for biological therapy as exemplified by ustekinumab

Introduction of biotherapeutics has been a major milestone in the treatment of different chronic diseases. Nevertheless, the immune system can recognize the administered biological as non-self and respond with generation of anti-drug antibodies (ADA), including neutralizing ADA (nADA). Immunogenic responses may result in altered drug dynamics and kinetics leading to changes in safety and efficacy. However, there are several challenges with standard techniques for immunogenicity testing. Ustekinumab (UST), used in different inflammatory diseases, is a therapeutic antibody directed against the shared p40 subunit of interleukin (IL)-12 and IL-23, interfering in the pathogenically crucial T helper type 1 (Th1)/Th17 pathway. We established and validated different approaches for detection and quantitation of UST, UST-specific ADA and nADA. Addressing the obstacle of complex formation of UST with nADA, we developed an acidification assay to approach the total amount of nADA. Validated methods were based on surface plasmon resonance spectroscopy (SPR), enzyme-linked immunosorbent assay (ELISA) and a cell-based approach to characterize neutralizing capacity of nADA. Parameters assessed were determination and quantitation limits, linearity, range, precision, accuracy and selectivity. Quantitation of ADA and UST was feasible at lower concentrations using ELISA, whereas SPR showed a wider linear range for determination of ADA and UST. Accuracy, precision and linearity for quantitation were comparable using ELISA, SPR and the cell-based approach. All validated parameters fulfill the requirements of regulatory agencies. A combination of the testing approaches could address the increasing demand of precision medicine as it can be suitable for capturing the whole spectrum of immunogenicity and is transferable to other biologicals.

[Do we still need clinical studies in rheumatology?]

Despite a large number of approved therapies demonstrating efficacy in the treatment of rheumatic diseases, only 60-85 % of patients with the indications for rheumatoid arthritis are adequately treated in Germany. Additionally, approved therapies for other immune-mediated diseases are often entirely lacking, indicating the great medical need for the development of new innovative therapies in this specialized field. The development of new drugs is expensive due to the high costs of conducting clinical trials in all phases of development up to obtaining approval; therefore, pharmaceutical companies are looking for ways to save costs in the particular developmental stages. Although the classical regions for drug development (i.e. western Europe, the USA and Japan) offer both a high level of data quality and a good infrastructure to conduct clinical trials due to high standards of education and quality, clinical trials are expensive in these regions. Beside high costs, the comparatively low recruitment rates in these regions are one of the main reasons for the shifting of drug developmental stages from classical regions to eastern European, Latin American and Asian countries, which provide services for drug development and high recruitment rates for comparatively less money. However, there are many strong arguments for the participation of regions in western Europe, especially German sites in clinical trials. In this article these arguments are discussed and possible solutions and strategies for conducting and compensation of study centers in Germany for clinical trials in the field of rheumatology are provided.

Increased Serum Levels of the IL-33 Neutralizing sST2 in Limited Cutaneous Systemic Sclerosis

The pathophysiology of both limited cutaneous systemic sclerosis (lcSSc) and diffuse cutaneous SSc (dcSSc), representing two subtypes of an autoimmune disease of the connective tissue, is still enigmatic. Life-limiting, progressive fibrotic changes as a consequence of vasculopathy and autoimmunity are characteristic in varying extent for lcSSc and dcSSc. Previously, an increased IL-33 serum concentration in early phase SSc patients and an elevated tissue expression of its receptor, ST2L, on endothelial cells (EC) were described. While suggested as a biomarker for fibrotic diseases, for example liver fibrosis, the role of soluble ST2 (sST2) in the pathological processes and its contribution to vascular fibrosis in SSc has not been investigated. Here, we showed that sST2 is elevated in late phase limited cutaneous SSc (lcSSc) as compared to patients with shorter disease duration or with the diffuse subtype of SSc. We demonstrated that sST2, not IL-33, is significantly increased in serum of lcSSc patients with disease duration over 9 years. Soluble ST2 was not elevated in healthy controls or in SSc patients with early skin involvement or disease duration shorter than 9 years. Furthermore, we observed that sST2 serum levels were lowered by iloprost (prostacyclin) treatment. After 5 days of iloprost infusion, sST2 serum levels fell in 6 of 7 patients. Therefore, we not only like to propose sST2 as a biomarker for progressive vascular fibrosis, but moreover, suggest that the involvement of sST2 in the pathogenesis of lcSSc may be exploited therapeutically.

Anti-TNFα-therapy as an evidence-based treatment option for different clinical manifestations of psoriatic arthritis

The development programmes of different TNF-blocking agents in psoriatic arthritis (PsA) not only provided substantial evidence for the therapeutic benefits of the specific treatment options, but also enabled new insights into the differential treatment effects on distinct disease manifestations. For the first time, specific robust evidence for distinctive effects on different manifestations of PsA, as a distinct entity separate from rheumatoid arthritis (RA), has been generated in a standardized way. The clearest evidence was shown for an effect on peripheral arthritis (polyarticular) with ACR20 response rates from 45 up to 58% (vs. 9-24% for placebo), and an inhibition of radiographic progression demonstrated for the first time for a treatment principle in PsA. However, as PsA does not remain confined to the peripheral joints, it was necessary to address diverse patterns of PsA-subtypes in the outcome measurements of the anti-TNF trials. Accordingly, the results of the clinical studies on anti-TNF treatment also have demonstrated efficacy on enthesitis, dactylitis and skin psoriasis, either in sub analysis of results from phase III RCTs, or in additional prospective studies.

[Pharmacotherapy of psoriatic arthritis. Treatment recommendations against the background of limited evidence]

International treatment recommendations for assisting the choice of pharmaceutical treatment of psoriatic arthritis are currently available in two different versions. While the group for research and assessment of psoriasis and psoriatic arthritis (GRAPPA) recommendations mainly focus on both the description of treatment options for the different phenotypes of psoriatic arthritis and the listing of evidence grades, the European League against Rheumatism (EULAR) recommendations try to implement the knowledge about drugs into an algorithm for the different treatment steps. However, the presentation of a treatment algorithm suggests comparable evidence levels for the individual treatment steps, which is at present not the case for psoriatic arthritis. This should be borne in mind for each individual treatment option and treatment step when using a predetermined therapy algorithm and in view of the heterogeneous study results (or no study results available). Both recommendations are currently being revised and will allow the latest evidence trends to be included in the updated version.

Development and validation of a new disease activity score in 28 joints-based treatment response criterion for rheumatoid arthritis

OBJECTIVE

To define a valid criterion for treatment response as assessed by the Disease Activity Score in 28 joints (DAS28) that exceeds random disease activity variations in patients with rheumatoid arthritis (RA).

METHODS

We utilized anonymized data sets of RA patients from multiple rheumatology centers in Germany to identify patients with stable responses to conventional or biologic disease-modifying antirheumatic drug (DMARD) therapy (discovery cohort). To evaluate fluctuations in DAS28 scores, we subjected patients' DAS28 scores at months 12, 18, and 24 to an analysis of variance model to establish a 1-sided 95% confidence interval for normal fluctuations; this value was used to define the critical difference (DAS28-dcrit ) for individual changes from baseline. The DAS28-dcrit value was then applied to analyses of therapeutic response in an adalimumab noninterventional study cohort.

RESULTS

The discovery cohort included 415 patients receiving stable treatment. Values for DAS28-dcrit were comparable regardless of age, sex, disease activity, and class of therapy (DMARDs or biologic agents) and fell below 1.8 in all subgroups. We therefore conclude that DAS28 improvements of 1.8 or higher are outside the normal variation and represent a therapeutic response. When applied to data from the adalimumab noninterventional study (n = 1,874), a DAS28-dcrit response was more robust over time than a European League Against Rheumatism response and was more closely correlated with improved functional capacity.

CONCLUSION

Based on our data, a DAS28-dcrit value of 1.8 signifies a positive individual therapeutic response that exceeds the threshold of random fluctuation. The DAS28-dcrit criterion may be useful in steering individual therapy and stratifying clinical trials.

[Personalized medicine in cytokine-targeted therapy]

Personalized healthcare tries to predict the effectiveness and safety in individual therapeutic approaches by defining individual patient characteristics (biomarkers), while stratification uses diagnostic patterns for groups of patients for prediction of therapeutic response with less adverse reactions caused by the drugs applied. Both methods are implemented in oncology and infectiology and in the therapy of rheumatological diseases there is a need for both. Cytokine-directed therapies are important for the treatment of rheumatological diseases, especially when therapy with conventional disease-modifying antirheumatic drugs (DMARD) has failed. Despite the high potency of these drugs for inhibiting pro-inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α), interleukin 1 (IL-1) and IL-6, sufficient responses are only seen in some of the patients. Therefore, stratification and personalized medicine are ways to optimize efficacy and tolerability of biologic therapies. Some initial evidence is available for potential future strategies using molecular and genetic markers for stratified cytokine inhibition.

[Diagnosis and therapy of early psoriatic arthritis]

Early diagnosis of psoriatic arthritis is of importance because an erosive disease is already detectable after a 2-year duration of symptoms. Often psoriatic arthritis cannot easily be detected because of the diversity of disease manifestations in early stages. As up to 30% of psoriasis patients develop psoriatic arthritis an interdisciplinary dermatologic/rheumatologic approach to diagnose findings and treatment decisions would be desirable. Screening tools, such as validated questionnaires allow an early detection and selection of patients with a high probability of psoriatic arthritis even in dermatological care or on a house physician basis. The implementation of the CASPAR criteria as a classification tool for psoriatic arthritis has also improved the diagnosis finding in patients with a recent onset of active musculoskeletal disease. Data from early psoriatic arthritis cohorts illustrate that drug-free remission is rare. An adequate treatment is of importance. The Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) has developed treatment recommendations based on the available evidence for different treatment modalities.