Advancements in the use of xenopus oocytes for modelling neurological disease for novel drug discovery

INTRODUCTION

Introduced about 50 years ago, the model of Xenopus oocytes for the expression of recombinant proteins has gained a broad spectrum of applications. The authors herein review the benefits brought from using this model system, with a focus on modeling neurological disease mechanisms and application to drug discovery.

AREAS COVERED

Using multiple examples spanning from ligand gated ion channels to transporters, this review presents, in the light of the latest publications, the benefits offered from using Xenopus oocytes. Studies range from the characterization of gene mutations to the discovery of novel treatments for disorders of the central nervous system (CNS).

EXPERT OPINION

Development of new drugs targeting CNS disorders has been marked by failures in the translation from preclinical to clinical studies. As progress in genetics and molecular biology highlights large functional differences arising from a single to a few amino acid exchanges, the need for drug screening and functional testing against human proteins is increasing. The use of Xenopus oocytes to enable precise modeling and characterization of clinically relevant genetic variants constitutes a powerful model system that can be used to inform various aspects of CNS drug discovery and development.

Nicotinic acetylcholine receptors in neurological and psychiatric diseases

Neuronal nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels that are widely distributed both pre- and post-synaptically in the mammalian brain. By modulating cation flux across cell membranes, neuronal nAChRs regulate neuronal excitability and the release of a variety of neurotransmitters to influence multiple physiologic and behavioral processes including synaptic plasticity, motor function, attention, learning and memory. Abnormalities of neuronal nAChRs have been implicated in the pathophysiology of neurologic disorders including Alzheimer's disease, Parkinson's disease, epilepsy, and Tourette´s syndrome, as well as psychiatric disorders including schizophrenia, depression, and anxiety. The potential role of nAChRs in a particular illness may be indicated by alterations in the expression of nAChRs in relevant brain regions, genetic variability in the genes encoding for nAChR subunit proteins, and/or clinical or preclinical observations where specific ligands showed a therapeutic effect. Over the past 25 years, extensive preclinical and some early clinical evidence suggested that ligands at nAChRs might have therapeutic potential for neurologic and psychiatric disorders. However, to date the only approved indications for nAChR ligands are smoking cessation and the treatment of dry eye disease. It has been argued that progress in nAChR drug discovery has been limited by translational gaps between the preclinical models and the human disease as well as unresolved questions regarding the pharmacological goal (i.e., agonism, antagonism or receptor desensitization) depending on the disease.

The importance of ligand gated ion channels in sleep and sleep disorders

On average, humans spend about 26 years of their life sleeping. Increased sleep duration and quality has been linked to reduced disease risk; however, the cellular and molecular underpinnings of sleep remain open questions. It has been known for some time that pharmacological modulation of neurotransmission in the brain can promote either sleep or wakefulness thereby providing some clues about the molecular mechanisms at play. However, the field of sleep research has developed an increasingly detailed understanding of the requisite neuronal circuitry and key neurotransmitter receptor subtypes, suggesting that it may be possible to identify next generation pharmacological interventions to treat sleep disorders within this same space. The aim of this work is to examine the latest physiological and pharmacological findings highlighting the contribution of ligand gated ion channels including the inhibitory GABA_A and glycine receptors and excitatory nicotinic acetylcholine receptors and glutamate receptors in the sleep-wake cycle regulation. Overall, a better understanding of ligand gated ion channels in sleep will help determine if these highly druggable targets could facilitate a better night's sleep.

Specificities of Meningitis and Meningo-Encephalitis After Kidney Transplantation: A French Retrospective Cohort Study

Kidney transplant recipients develop atypical infections in their epidemiology, presentation and outcome. Among these, meningitis and meningoencephalitis require urgent and adapted anti-infectious therapy, but published data is scarce in KTRs. The aim of this study was to describe their epidemiology, presentation and outcome, in order to improve their diagnostic and management. We performed a retrospective, multicentric cohort study in 15 French hospitals that included all 199 cases of M/ME in KTRs between 2007 and 2018 (0.9 case per 1,000 KTRs annually). Epidemiology was different from that in the general population: 20% were due to Cryptococcus neoformans, 13.5% to varicella-zoster virus, 5.5% to Mycobacterium tuberculosis, and 4.5% to Enterobacteria (half of which produced extended spectrum beta-lactamases), and 5% were Post Transplant Lymphoproliferative Disorders. Microorganisms causing M/ME in the general population were infrequent (2%, for Streptococcus pneumoniae) or absent (Neisseria meningitidis). M/ME caused by Enterobacteria, Staphylococci or filamentous fungi were associated with high and early mortality (50%-70% at 1 year). Graft survival was not associated with the etiology of M/ME, nor was impacted by immunosuppression reduction. Based on these results, we suggest international studies to adapt guidelines in order to improve the diagnosis and the probabilistic treatment of M/ME in SOTRs.

The molecular mechanism of snake short-chain α-neurotoxin binding to muscle-type nicotinic acetylcholine receptors

Bites by elapid snakes (e.g. cobras) can result in life-threatening paralysis caused by venom neurotoxins blocking neuromuscular nicotinic acetylcholine receptors. Here, we determine the cryo-EM structure of the muscle-type Torpedo receptor in complex with ScNtx, a recombinant short-chain α-neurotoxin. ScNtx is pinched between loop C on the principal subunit and a unique hairpin in loop F on the complementary subunit, thereby blocking access to the neurotransmitter binding site. ScNtx adopts a binding mode that is tilted toward the complementary subunit, forming a wider network of interactions than those seen in the long-chain α-Bungarotoxin complex. Certain mutations in ScNtx at the toxin-receptor interface eliminate inhibition of neuronal α7 nAChRs, but not of human muscle-type receptors. These observations explain why ScNtx binds more tightly to muscle-type receptors than neuronal receptors. Together, these data offer a framework for understanding subtype-specific actions of short-chain α-neurotoxins and inspire strategies for design of new snake antivenoms.

POS0207 UNRAVELING THE COMPLEX INTERACTION BETWEEN DISEASE ACTIVITY AND FATIGUE IN EARLY RA: A MEDIATION ANALYSIS WITH DATA FROM THE CareRA TRIAL

Background

Fatigue is recognized as one of the most important symptoms of rheumatoid arthritis (RA). Although inflammation is often proposed as the predominant pathophysiological mechanism, many patients with RA continue to experience fatigue despite inflammatory disease control. The relationship between RA disease activity and fatigue appears to be complex and is likely confounded by cognitive, emotional and social aspects.

Objectives

To unravel the complex interaction between disease activity and fatigue in early RA.

Methods

Data were analyzed from the 2-year treat-to-target trial Care in early RA (CareRA), which compared different remission-induction DMARD regimens, either with or without bridging glucocorticoids, in treatment-naïve patients with early RA. Fatigue was measured on a visual analog scale (VAS) at every study visit. The association between inflammatory disease activity (DAS28-CRP) and fatigue (VAS) over time was studied with a multilevel mediation analysis, including as mediators the individual components of the DAS28-CRP, pain (VAS), disability (HAQ), psychosocial aspects (Short-Form 36 [SF-36]), illness perceptions (Revised Illness Perception Questionnaire [IPQ-R]), and sleep quality (Pittsburgh Sleep Quality Index [PSQI]).

Results

A total of 356 patients were included in these analyses, with a mean (SD) fatigue (VAS) of 48/100 (24) at study initiation. Although there was a consistently positive association between DAS28-CRP and fatigue over time, this association was fully mediated by patient global assessment (PGA) and pain, and to a lesser extent by SF-36 Mental Health and the PSQI global score (Figure 1). Full mediation implies the absence of a significant direct association between DAS28-CRP and fatigue after adjusting for these mediators. In addition, no mediating effect was found for tender/swollen joint counts or CRP.

Figure 1.

Mediation analysis of the association between DAS28-CRP and fatigue (VAS) over time.

Reported are the standardized regression coefficients with indicators of significance (* p < 0.05; ** p < 0.01; *** p < 0.001). DAS28-CRP = Disease Activity Score in 28 joints with C-reactive protein, SJC28/TJC28 = swollen/tender joint count in 28 joints, HAQ = Health Assessment Questionnaire, SF-36 = Short-Form 36, MH = mental health, RE = emotional role functioning, SF = social functioning, IPQ-R = Revised Illness Perception Questionnaire, PSQI = Pittsburgh Sleep Quality Index

Conclusion

Our mediation analysis suggests that the relationship between disease activity and fatigue in early RA is complex and fully mediated by aspects of wellbeing like pain, mental health, sleep quality, and the patient’s overall assessment of disease. These results imply a mainly indirect relation between fatigue and inflammation. Clinicians should reserve specific attention for the psychosocial determinants of fatigue, particularly when no improvement is seen with DMARDs.

Disclosure of Interests

Michaël Doumen: None declared, Sofia Pazmino: None declared, Delphine Bertrand: None declared, Diederik De Cock: None declared, Johan Joly: None declared, Rene Westhovens Speakers bureau: Honoraria for lectures:

- Celltrion

- Gilead

- Galapagos, Consultant of: - Celltrion

- Gilead

- Galapagos, Patrick Verschueren Speakers bureau: MSD

Galapagos

Eli Lilly, Consultant of: Sanofi

Galapagos

Pfizer

Gilead, Grant/research support from: Pfizer Chair Management of Early Rheumatoid Arthritis at KU Leuven Belgium

AB1395 PATIENTS’ AND RHEUMATOLOGISTS’ PERCEPTIONS REGARDING TAPERING OF RITUXIMAB

Background

Rituximab is an efficacious drug for the treatment of Rheumatoid Arthritis (RA). The commonly used dose consists of two infusions of 1000 mg with a 2-week interval, but evidence is growing that a lower dose could be as effective. Before implementing a tapering strategy, understanding the perceptions of patients and rheumatologists in this regard is important.

Objectives

The aim was to investigate patients’ and rheumatologists’ perceptions on rituximab tapering.

Methods

Patients with RA, who were currently or previously treated with rituximab, and rheumatologists were invited to participate in a qualitative study consisting of individual, in depth, face-to-face, semi-structured interviews. Participants were recruited based on purposive sampling to ensure diversity. Interviews were conducted via video or telephone call. Additional participants were interviewed until data saturation was achieved, meaning no new information emerged from the last 3 interviews. Interviews were audiotaped and transcribed verbatim, followed by analysis according to the Qualitative analysis guide of Leuven, which generated themes. Patient experts were involved in this research.

Results

In total, 16 patients with RA and 13 rheumatologists were interviewed. Four themes were found: In favour/reluctant of tapering, shared decision making, implementation and evidence gap (Figure 1). Patients and rheumatologists were IN FAVOUR of rituximab tapering, for reasons of safety and economic benefit. Patients and rheumatologists mentioned that a lower dose could allow shorter retreatment intervals, which might avoid flares. Furthermore, rheumatologists referred to available evidence of the effectiveness of a lower rituximab dose. Additionally, patients and rheumatologists indicated that the dose could be tailored based on the patient’s clinical manifestations, e.g. usual cycle interval and disease activity measures. However, some patients and rheumatologists felt RELUCTANT towards rituximab tapering. Patients and rheumatologists were concerned about potential loss of effectiveness and quality of life, next to more practical concerns. Rheumatologists mentioned that they had insufficient experience with rituximab in general to feel comfortable with tapering. Moreover, when applying an on-flare retreatment strategy, patients present with an active disease at the time of retreatment and therefore the option of tapering is less appealing. The next theme was SHARED DECISION MAKING. Patients and rheumatologists mentioned that patients have trust in their physician and thus leave the tapering decision in the hands of the rheumatologists. However, rheumatologists added that this should be combined with explanation of the tapering rationale. Another theme was IMPLEMENTATION. When asking participants about 2 possible dose reduction regimens, a cycle consisting of 2 infusions with a lower dose or a cycle of only 1 infusion with a higher dose, advantages were raised for both regimens (e.g. safety reasons and time savings, respectively). On the other hand, the on-flare retreatment regimen itself was already perceived as a kind of tapering, as the interval is prolonged as much as possible between the cycles. EVIDENCE GAP was the last theme, meaning that patients and rheumatologists felt there was a need of more research regarding rituximab tapering. For instance, predictive tools for flares, as well as the possibility of subcutaneous administration of rituximab, were mentioned as unmet needs by rheumatologists.

Figure 1.

Conceptual framework of the patients’ and rheumatologists’ perceptions regarding tapering of rituximab. (Icons: Iconfinder)

Conclusion

It seems that rituximab tapering is not yet incorporated in daily practice as much as tapering of other antirheumatic drugs and this could potentially be related to a lack of experience with rituximab. However, with appropriate education and communication, rheumatologists and patients are willing to taper rituximab. Although, many questions remain, indicating an evidence gap and a need of more research.

Disclosure of Interests

None declared

OP0301-HPR Patient Adherence to e-Health Interventions for Remote Disease Monitoring in Chronic Arthritis

Background

Chronic inflammatory arthritides require lifelong follow-up and treatment. Electronic health (eHealth) could be used to remotely monitor disease, possibly improving patient self-management and lowering the burden of in-person consultations. For clinical use, it is important to understand adherence rates of patients with chronic arthritis to eHealth tools.

Objectives

To systematically review the literature on adherence to eHealth tools for remote monitoring of symptoms or disease activity in chronic arthritis.

Methods

We systematically searched the following databases: Embase, PubMed, Cochrane Central, CINAHL, Web of Science, Clinicaltrials.gov, and the International Clinical Trials Registry Platform (ICTRP). Eligible articles reported adherence rates to an eHealth tool in patients with rheumatoid arthritis (RA), juvenile idiopathic arthritis (JIA), spondyloarthritis (SpA), osteoarthritis (OA), or gout. Included texts were screened individually. Finally, quality assessment was done with the Newcastle-Ottawa scale (NOS) and the PEDro scale.

Results

The literature search resulted in 7027 articles. After deduplication, 4219 articles were screened for eligibility, and 47 articles were included. We found highest adherence rates in studies applying electronic diaries (81.8%), followed by text messages (79.9%), web-based platforms (74.6%), activity trackers (73%), and smartphone applications (65.5%). Highest adherence was reported in studies on patients with OA (79.7%), followed by patients with gout (73.7%), RA (71.3%), ankylosing SpA (67%), and JIA (59%). Demographic characteristics did not seem to affect patient adherence. Based on frequency of data entering, a time interval of once-daily showed highest adherence rates (72.6%), followed by entering data more than once a day (72.3%) and once a week (67.7%), or longer (59.2%). Adherence declined with longer study duration.

Conclusion

Our literature review identified declining adherence levels with longer study duration, and highest adherence rates for patients with OA, making use of electronic diaries, and requesting once-a-day completion. OA studies had an overall shorter duration than RA studies, which could be an explanation as to why OA patients showed higher adherence. Lower adherence rates were reported in studies in juvenile populations, while older age did not seem to affect reported adherence.

Figure 1.

Linear regression model of adherence based on study duration per disease. X = study duration (days), Y = adherence (%). Y = -0.0332X + 71.84. Light blue = RA, yellow = OA, dark blue = JIA, red = Gout, green = SpA, white = >1 disease

Table 1.

Included studies. Adh = adherence SA = smartphone app, ED = electronic diary, AT = activity tracker, OP = online platform, TM= text message. JIA= Juvenile Idiopathic Arthritis, PsA = Psoriatic Arthritis, SpA = Spondyloarthritis, OA = osteoarthritis, RA = Rheumatoid arthritis

StudyDiseaseEHealthAdh (%)StudyDiseaseEHealthAdh (%)StudyDiseaseEHealthAdh (%)Skrepnik, ‘17OAAT/SA91 AT 36 SABeukenhorst, ‘20OAAT/SA75 AT 62 SAMcKenna, ‘18RAAT43Lee, ‘20JIASA51Nowell, ‘20RAAT/SA82 AT 72 SAYu, ‘20OAAT99Serlachius, ‘19GoutSA67Heiberg, ‘07RAED95Zaslavsky, ‘19OAAT/SA85Pers, ‘21RASA67Connelly, ‘11JIAED71Gossec, ‘18RAOP63Heale, ‘18JIAAT/SA19 ATConnelly, ‘10JIAED88Walter, ‘14RAOP61Reade, ‘17RASA77Bromberg, ‘16JIAED66Christodoulou, ‘14OAOP98Bellamy, ‘10OASA100Bromberg, ‘14JIAED66Renskers, ‘20RA/SpAOP68Seppen, ‘20RASA69Franceschelli, ‘19OAED/Tyrell, ‘16SpAOP67Harbottle, ‘18JIAAT/SA17 SABingham, ‘19RAED94Martin, ‘21RAOP69Pouls, ‘20GoutSA94Connelly, ‘17JIAED87Kai, ‘19OAOP52Colls, ‘21RASA79Stinson, ‘08JIAED72Richter, ‘21RAOP98Brayne, ‘21RASA41Wilson, ‘13OAED83Broderick, ‘13OAOP>95Austin, ‘20RASA91Jacquemin, ‘18RA/SpAAT88Zuidema, ‘19RAOP71Crouthamel, ‘18RASA20Elmagboul, ‘20GoutAT61Barber, ‘18RAOP69Nowell, ‘21AS, OA, SpA, RASA55Östlind, ‘21OAAT/SA88 ATChristie, ‘14RA/SpATM98Lee, ‘12RATM73

Disclosure of Interests

None declared

POS0523 FATIGUE TRAJECTORIES IN PATIENTS WITH EARLY RHEUMATOID ARTHRITIS: A LONGITUDINAL ANALYSIS OF DATA FROM THE CareRA TRIAL

Background

Fatigue is a common and impactful symptom of rheumatoid arthritis (RA). Given its heterogeneity and unpredictable nature, studies on contributing factors of RA-related fatigue should include multidimensional measures of fatigue and assess these longitudinally with multivariate methods, starting early in the disease.

Objectives

We aimed to explore the longitudinal course of fatigue and its predictors among patients with early RA starting DMARD therapy.

Methods

Data came from the 2-year treat-to-target trial Care in early RA (CareRA) and its 3-year extension. Fatigue was measured based on visual analog scale (VAS), Multidimensional Fatigue Inventory (MFI), and Short-Form 36 (SF-36). Longitudinal fatigue trajectories were identified with multivariable growth mixture modeling. Baseline and early predictors of trajectory membership, including treatment response, were studied with multinomial logistic regression adjusted for age, gender, and treatment type. Patient global assessment (PGA), pain (VAS), and disability (HAQ) were studied in separate models because of collinearity (Spearman r > 0.60). For all models, posterior probabilities of trajectory assignment were included in the regression as weights to account for classification uncertainty. Treatment response was defined, based on whether remission (DAS28-CRP < 2.6) was achieved by week 16 and sustained until year 2, as either early persistent response, secondary failure, or delayed response.

Results

In total, 356 and 244 patients were included in the 2-year and 5-year analyses, respectively. Mean (SD) fatigue (VAS) at inclusion was 48/100 (24). Four fatigue trajectories were identified: Rapid, Gradual, and Transient Improvement, and Early Deterioration, consisting of 10%, 14%, 56%, and 20% of patients, respectively (Figure 1). Higher PGA, pain and HAQ at baseline were associated with increased probability of Rapid Improvement compared to Transient Improvement or Early Deterioration (Table 2). Secondary treatment failure and delayed treatment response strongly increased the probability of less positive fatigue trajectories when compared to early persistent response.

Figure 1.

Latent trajectories of fatigue evolution over the first 2 years in CareRA (n = 356).

Conclusion

The longitudinal course of fatigue in early RA is dynamic but highly refractory, with less than 25% of patients making lasting improvements and 20% even experiencing worsening fatigue despite intensive DMARD therapy. Remarkably, a higher perceived disease impact at baseline was associated with an increased probability of fatigue improvement, possibly reflecting the fluctuating nature of this complex symptom. However, early inflammatory disease control appears to be the most important contributor to improved long-term fatigue outcomes, illustrating the far-reaching impact of the therapeutic window of opportunity in early RA.

References

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Table 1.

Predictors of fatigue trajectory membership

Gradual improvementTransient improvementEarly deteriorationOR (95% CI)pOR (95% CI)pOR (95% CI)pFatigue (0-100)1.01 (0.99; 1.04)0.320.99 (0.97; 1.01)0.160.98 (0.96; 1.00)0.07PGA (0-100)0.98 (0.95; 1.01)0.110.96 (0.94; 0.99)0.0030.95 (0.92; 0.98)<0.001Tender joints (0-28)1.00 (0.91; 1.13)0.821.00 (0.91; 1.09)0.970.99 (0.88; 1.11)0.80Swollen joints (0-28)1.01 (0.90; 1.15)0.820.99 (0.89; 1.10)0.830.93 (0.81; 1.06)0.30CRP (mg/dL)1.00 (0.98; 1.01)0.670.99 (0.98; 1.01)0.361.00 (0.97; 1.02)0.66Pain (0-100)0.99 (0.96; 1.02)0.360.96 (0.94; 0.98)0.0020.95 (0.92; 0.98)<0.001HAQ (0-3)1.07 (0.52; 2.20)0.850.55 (0.30; 1.01)0.050.24 (0.11; 0.51)<0.001SF-36 Mental Component Score (0-100)1.00 (0.96; 1.04)0.971.02 (0.99; 1.06)0.231.02 (0.98; 1.06)0.34Treatment responseSecondary failure2.22 (0.78; 6.32)0.133.87 (1.57; 9.55)0.0037.88 (2.68; 23.13)<0.001Delayed response2.93 (0.70; 12.15)0.146.82 (1.91; 24.44)0.00311.14 (2.33; 53.19)0.003

Disclosure of Interests

Michaël Doumen: None declared, Sofia Pazmino: None declared, Delphine Bertrand: None declared, Diederik De Cock: None declared, Johan Joly: None declared, Rene Westhovens Speakers bureau: - Celltrion

- Galapagos

- Gilead, Consultant of: - Celltrion

- Galapagos

- Gilead, Patrick Verschueren Speakers bureau: - MSD

- Eli Lilly

- Galapagos, Consultant of: - Sanofi

- Galapagos

- Gilead

- Pfizer, Grant/research support from: Pfizer Chair Management of Early Rheumatoid Arthritis at KU Leuven Belgium

AB1394 ON-FLARE RETREATMENT WITH RITUXIMAB IN RHEUMATOID ARTHRITIS: PATIENTS’ AND RHEUMATOLOGISTS’ PERCEPTIONS

Background

Rituximab is an efficacious drug for the treatment of Rheumatoid Arthritis (RA). According to literature, administration of rituximab can be based on a fixed interval or on relapse of disease activity. In some countries, like Belgium, after the first rituximab cycle a flare is required for reimbursement of a subsequent cycle. A better understanding of the perceptions of patients and rheumatologists regarding this retreatment strategy would be informative in view of potential adjustments.

Objectives

The aim was to investigate patients’ and rheumatologists’ perceptions on the on-flare retreatment strategy of rituximab.

Methods

Patients with RA, who were currently or previously treated with rituximab, and rheumatologists were invited to participate in a qualitative study consisting of individual, in depth, face-to-face, semi-structured interviews. Participants were recruited based on purposive sampling to ensure diversity. Interviews were conducted via video or telephone call. Additional participants were interviewed until data saturation was achieved, meaning no new information emerged from the last 3 interviews. Interviews were audiotaped and transcribed verbatim, followed by analysis according to the Qualitative analysis guide of Leuven, which generated themes and subthemes. Patient experts were involved in this research.

Results

In total, 16 patients with RA and 13 rheumatologists were interviewed. Five overarching themes were generated from the interviews: flare definition, recognition, reaction, balance between benefits and barriers and suggestions (Figure 1). Patients and rheumatologists described how they perceive the on-flare retreatment strategy in daily practice, starting with the FLARE DEFINITION itself. Namely, what patients perceived as a flare and the impact of this flare. The second step was RECOGNITION of the flare. Both rheumatologists and patients indicated that patients are able to recognise a flare. However, the patient’s ability to discriminate between inflammatory and other types of pain was perceived as a difficulty. Moreover, patients indicated that depending on the flare’s intensity, they can cope with it themselves, delaying the need for a rituximab cycle. The next step after correctly recognising a flare, was the REACTION, from both the patient’s and rheumatologist’s side. It was stressed that patients must contact their treating rheumatologists in time. Furthermore, a swift response of the rheumatologists was perceived as important. After confirming eligibility, the shared decision to plan a new rituximab cycle can be made while keeping an eye on the organisation. Remarkably, it seemed that rheumatologists approached the retreatment strategy in different ways, meaning that not everyone adhered to the on-flare principle. Several perceived BENEFITS (e.g. lower safety risk, societal cost savings) and BARRIERS (e.g. disease activity fluctuations, slow working mechanism) were mentioned, making clear that the optimal retreatment strategy should be based on a BALANCE between both. Finally, some SUGGESTIONS (e.g. biomarkers for flare prediction, subcutaneous administration of rituximab) were brought up that could be helpful in applying the optimal retreatment strategy.

Figure 1.

Conceptual framework of the perceptions of patients and rheumatologists regarding the on-flare retreatment strategy with rituximab. SDM = Shared decision making. (Icons: Iconfinder)

Conclusion

Patients play an important role in the recognition of flares and their reaction, in shared decision with the rheumatologist, contributes to the effectiveness of the rituximab on-flare retreatment strategy. Rheumatologists handle the on-flare retreatment strategy as pragmatically as possible, resulting in different approaches. Moreover, both benefits and barriers of on-flare retreatment were perceived, making clear that a balance should be found to determine the optimal retreatment strategy.

Disclosure of Interests

None declared

OP0032 AN ECONOMIC WINDOW OF OPPORTUNITY FOR PATIENTS WITH EARLY RHEUMATOID ARTHRITIS: 5-YEAR COST-EFFECTIVENESS ANALYSIS OF THE CareRA TRIAL

Background

The CareRA trial showed that remission induction with methotrexate (MTX) and glucocorticoid (GC) bridging in a treat-to-target setting is cost-effective up to 2 years in early Rheumatoid Arthritis (eRA) patients.

Objectives

To evaluate the long-term cost-effectiveness of treat-to-target treatments among recently diagnosed (<1 year), DMARD naïve patients with eRA using MTX and a step-down GC scheme (COBRA-Slim) compared to (a) the same combination with either sulphasalazine (COBRA-Classic) or leflunomide (COBRA-Avant-Garde) in high-risk patients and (b) MTX without GCs (Tight-Step-Up: TSU) in low-risk patients up to 5 years.

Methods

We used data from the 2-year RCT CareRA trial and its 3-year observational follow-up, CareRA plus. Patients completing the 2-year visit of CareRA were eligible for participation in CareRA plus, in which patients were evaluated every 6 months till year 5. Healthcare costs considered in this piggyback economic analysis were rheumatology visits, RA-related medication (synthetic and biological DMARDs, GCs, and all recorded analgesics including paracetamol, non-steroidals, tramadol and opioids), hospital admissions, laboratory tests and radiographs occurring during the 5-year trial. All pricing is based on December 2021 rates. Total costs per resource were calculated by multiplying the number of resources by the cost unit price extracted from Belgian national websites. Total costs per patient were obtained by summing costs of all resources. Effectiveness was measured with DAS28-CRP and compared between the originally allocated treatment arms. An incremental cost-effectiveness ratio (ICER) was calculated by dividing the cost difference by the DAS28-CRP<2.6 remission difference per pair of treatment schemes. Multiple imputation was used to handle missing data and non-parametric bootstrapping with 25000 iterations of random sampling with replacement to calculate confidence intervals (95% CIs).

Results

Of 322 eligible patients, 252 were included in CareRA plus, of which 203 completed the trial. Rates of disease control (DAS28-CRP<2.6) at year 5 in high-risk patients were 68%, 72% and 64% in the Classic, Slim and Avant-Garde group respectively (p=0.63) and related total costs were €11 358.39 (CI 7 776.84-14 939.93), €8 463.12 (CI 6 789.44-10 136.80), €11 752.47 (CI 7 705.11-15 799.82) respectively. In the low-risk population, 80% of patients in Slim and the TSU arm reached remission (DAS28-CRP<2.6) at year 5. While the costs were €6 332.55 (CI 3 607.63-9 057.48) for Slim, and €10 398.19 (CI 4165.95-16630.43) for TSU. In the high-risk group, Classic (ICER -€723.82) and Avant-Garde (ICER -€411.17) were more expensive and less effective compared to Slim. In the low-risk group, Slim was less expensive (Δ -€4 065.64) and equally effective as TSU. Figure 1 depicts how the different medication costs evolved during the 5-year follow-up. 22% of all patients were ever on bDMARDs. More specifically in 23% (16/69) of Classic, 21% (16/75) of Slim high-risk, 25% (15/59) of Avant-Garde, 17% (4/23) of Slim low-risk, and in 15% (4/26) of TSU patients. On average a first bDMARD was started later in the Slim arms, more specifically at week 69 for Classic, week 106 for Slim high-risk, week 97 for Avant-Garde, week 102 for Slim low-risk and week 76 for TSU.

Conclusion

The combination of MTX with a GC bridging scheme (COBRA Slim) was more cost-effective (less expensive with comparable disease control) than more intensive step-down combination strategies or a conventional step-up approach 5 years after initial treatment. Over 5 years, around one-fifth of all patients, were in need of starting biological treatment and the transition to a bDMARD was later in COBRA Slim. These results point out the possibility of an early “economic” window of opportunity for diminishing costs long-term while still maintaining optimal disease control.

Disclosure of Interests

None declared

Belgian rheumatologists' preferences regarding measures of disease activity in patients with rheumatoid arthritis: results from a mixed-methods study

The reliability and clinical usefulness of the different composite disease activity scores and their individual components in Rheumatoid Arthritis (RA) are still debated. This study investigated which measures of disease activity were preferred by rheumatologists. A mixed-method study was performed. First, ten Belgian rheumatologists were invited for individual interviews on their current practice and preferences for measurement of RA disease activity. Results of this qualitative study and evidence from literature served as input for developing a survey. This survey asked rheumatologists to rate preferred standard disease activity score(s), their individual components, ultrasound and related patient-reported outcomes (PROs), by maximum difference scaling. The relative importance score (RIS) for each indicator was calculated using hierarchical Bayes modeling. The qualitative study included 6/10 invited rheumatologists. Composite scores and components were perceived as useful, while PROs were found subjective. Interestingly, ultrasound was used to mediate discrepancies between physician and patient. The survey based on this was sent to 244 Belgian rheumatologists, 83/244 (34%) responded, including 66/83 (80%) complete and 17/83 (20%) incomplete surveys (two missing essential information). Most rheumatologists (75/81, 93%) used a disease activity score and 68/81 (84%) preferred the DAS28-CRP. Swollen joint count obtained the highest mean ± SD RIS (22.54 ± 2.64), followed by DAS28 ESR/CRP (20.61 ± 4.06), ultrasound (16.47 ± 7.97), CRP (13.34 ± 6.11) and physician's global assessment (12.59 ± 7.83). PROs including fatigue, pain, and patient's global assessment, and Health Assessment Questionnaire, obtained the lowest mean RIS (0.34-2.54). Rheumatologists place more faith in self-assessed disease activity components or in laboratory tests. Trust in PROs to evaluate disease activity is low in clinical practice.

Tapering of Etanercept is feasible in patients with Rheumatoid Arthritis in sustained remission: a pragmatic randomized controlled trial

Objective: In patients with rheumatoid arthritis (RA) in sustained remission, tapering of biological disease-modifying anti-rheumatic drugs can be considered. Tapering has already been investigated, but its feasibility remains to be determined. Therefore, we explored the feasibility of tapering etanercept in RA in a setting close to practice.Method: Patients with RA in 28-joint Disease Activity Score (DAS28) remission (≥ 6 months) and treated with etanercept 50 mg weekly (≥ 1 year) were included in the pragmatic 1 year open-label multicentre randomized controlled TapERA (Tapering Etanercept in Rheumatoid Arthritis) trial. Patients were assigned to continue etanercept weekly or to taper to every other week (EOW). Patients who lost remission [DAS28-C-reactive protein (CRP) ≥ 2.6] were re-escalated to etanercept weekly. The primary outcome was the proportion of patients maintaining DAS28-CRP remission for 6 months.Results: Sixty-six patients were randomized to etanercept weekly (n = 34) or EOW (n = 32). After 6 months, 26/34 patients (76%) in the weekly and 19/32 (59%) in the EOW group maintained disease control (p = 0.136). In the EOW group, 20/32 patients (63%) remained on their tapered treatment during the trial. Two patients reintroduced weekly etanercept themselves. Ten patients were re-escalated to etanercept weekly by the rheumatologist, after a median (interquartile range) interval of 3.0 (2.0-6.0) months. Among these patients, 7/10 regained remission after re-escalation, four of them at the next study visit.Conclusions: Although non-inferiority could not be demonstrated, tapering of etanercept to EOW appeared feasible in patients in sustained remission.

Regulation of a pentameric ligand-gated ion channel by a semiconserved cationic lipid-binding site

Pentameric ligand-gated ion channels (pLGICs) are crucial mediators of electrochemical signal transduction in various organisms from bacteria to humans. Lipids play an important role in regulating pLGIC function, yet the structural bases for specific pLGIC-lipid interactions remain poorly understood. The bacterial channel ELIC recapitulates several properties of eukaryotic pLGICs, including activation by the neurotransmitter GABA and binding and modulation by lipids, offering a simplified model system for structure-function relationship studies. In this study, functional effects of noncanonical amino acid substitution of a potential lipid-interacting residue (W206) at the top of the M1-helix, combined with detergent interactions observed in recent X-ray structures, are consistent with this region being the location of a lipid-binding site on the outward face of the ELIC transmembrane domain. Coarse-grained and atomistic molecular dynamics simulations revealed preferential binding of lipids containing a positive charge, particularly involving interactions with residue W206, consistent with cation-π binding. Polar contacts from other regions of the protein, particularly M3 residue Q264, further support lipid binding via headgroup ester linkages. Aromatic residues were identified at analogous sites in a handful of eukaryotic family members, including the human GABAA receptor ε subunit, suggesting conservation of relevant interactions in other evolutionary branches. Further mutagenesis experiments indicated that mutations at this site in ε-containing GABAA receptors can change the apparent affinity of the agonist response to GABA, suggesting a potential role of this site in channel gating. In conclusion, this work details type-specific lipid interactions, which adds to our growing understanding of how lipids modulate pLGICs.

Ligand gated receptor interactions: A key to the power of neuronal networks

The discovery of the chemical synapse was a seminal finding in Neurobiology but the large body of microscopic interactions involved in synaptic transmission could hardly have been foreseen at the time of these first discoveries. Characterization of the molecular players at work at synapses and the increased granularity at which we can now analyze electrical and chemical signal processing that occur in even the simplest neuronal system are shining a new light on receptor interactions. The aim of this review is to discuss the complexity of some representative interactions between excitatory and inhibitory ligand-gated ion channels and/or G protein coupled receptors, as well as other key machinery that can impact neurotransmission and to explain how such mechanisms can be an important determinant of nervous system function.

POS0616 LONG-TERM EFFECTIVENESS AFTER MULTIPLE CYCLES WITH RITUXIMAB FOLLOWING AN ON-FLARE RETREATMENT STRATEGY IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

Rituximab is known as an efficacious drug for the treatment of Rheumatoid Arthritis (RA). The recommended administration schedule consist of 2 infusions of 1000 mg with a 2-week interval. In Belgium an on-flare retreatment strategy is followed, making evaluation of effectiveness over time challenging. Moreover the patient’s view on this strategy is unclear.

Objectives:

To explore long-term effectiveness and safety of rituximab in daily clinical practice in patients with RA.

Methods:

Data of patients diagnosed with RA and treated with rituximab in a tertiary university hospital were retrospectively collected. For every cycle, clinical data were recorded at the time of the first and second infusion, the 16-week visit and the visit on which the treating rheumatologist decided to prescribe a new cycle. Data on demographics, previous RA treatment, disease activity, patient-reported outcomes, adverse events related to rituximab, dose and number of cycles were collected from 01/01/2006 until 01/12/2019 or until discontinuation of rituximab. The visit on which rituximab was prescribed for the first time was considered as the baseline visit. The data were analysed descriptively.

Results:

Data of 66 patients with RA were collected. The median (IQR) age was 57.0 (47.0-65.0) years at baseline and 56% (37/66) were female. Most patients were seropositive (RF 91% and ACPA 92%), and had erosive (71%) or nodular disease (53%). The median (IQR) disease duration was 12.5 (4.0-18.3) years. In total, 94% of the patients had failed at least one other biological Disease-modifying Antirheumatic Drug (bDMARD) before starting rituximab. Overall, patients received a median (IQR) of 3 (2-7) cycles of rituximab. Seven of the 66 patients (11%) discontinued rituximab and changed to another bDMARD after a median (IQR) of 1 (1-6) cycles and 11% were treated with a lower dose than 2x1000mg. The median (IQR) interval between the first 2 cycles was 7.0 (6.0-10.0) months, after which this increased to up to one year (interval between cycle 2-3: 10.0 (7.0-13.0) months, cycle 3-4: 12.0 (7.3-15.5) months). The overall median (IQR) follow-up time was 45.5 (14.8-82.3) months. The efficacy of rituximab remained after repeated cycles: after every treatment with rituximab, a reduction in disease activity based on the disease activity score in 28 joints (DAS28) could be noticed (figure 1A). The evolution in patients’ (PaGH) and physicians’ global health (PhGH) assessment followed the same pattern as the DAS28-score (Figure 1B). High PaGH-scores could be noticed at every start of a new rituximab cycle. The proportion of patients with a PaGH-score above 20 ranged from 84% - 100%, 74% - 100% and 66% - 86% at the first infusion, second infusion and week 16 visits, respectively. Rituximab was considered to be well-tolerated. In total, 23 adverse events in 12 patients were recorded and none of them were serious.

Conclusion:

Rituximab can be considered a highly efficacious drug for RA treatment in daily practice. There were no major side effects and there was an increasing treatment interval over time. However, a healthy survivor effect should be kept in mind when interpreting the results. It should be noted that with the on-flare retreatment strategy, every new rituximab cycle was preceded by a rise in PaGH-scores, which reflects a state of impaired wellbeing reported by patients. This should be further studied with qualitative methods and in a randomized trial setting comparing on-flare with fixed-interval retreatment to evaluate optimal effectiveness.

Figure 1.

Evolution in median - interquartile range disease activity (DAS28CRP) (A) and patients’ (PaGH) and physicians’ global health (PhGH) (B) over the different rituximab cycles. The disease activity, PaGH and PhGH were measured at baseline, the time of the first and second infusion, W16 and the visit on which a new rituximab cycle was prescribed. The dotted lines represent a DAS28CRP-score of 2.6 (remission cut-off) and 3.2 (low disease activity cut-off). C: cycle; W: week; VAS: visual analogue scale.

Disclosure of Interests:

None declared

AB0109 VALIDATION OF SEPARATE PATIENT-REPORTED, CLINICAL AND LABORATORY FACTOR SCORES AS REPRESENTATION OF DISEASE BURDEN IN A POPULATION WITH ESTABLISHED RHEUMATOID ARTHRITIS

Background:

Rheumatoid arthritis (RA) can cause important bio-psychosocial burden. When exploring disease burden evolution in the 2-year Care in early RA (CareRA) trial, 3 factor scores were extracted via exploratory factor analysis (EFA).1 EFA uncovers the fact that multiple observed variables have similar patterns of responses because they are all associated with a latent, not directly observable, variable.

Objectives:

To validate in a population with established RA, the 3 factors scores and their individual components originally extracted in CareRA.

Methods:

Patients with established RA in sustained remission under treatment with etanercept (≥1 year) were enrolled in the TapERA (Tapering Etanercept in RA) trial between 2012 and 2014. Patients completed the Flare Assessment in RA (FLARE-RA) questionnaire.2

Components of disease activity scores (swollen/tender joint count, physician and patient global health assessment, CRP and ESR), as well as pain (question 2) and fatigue evaluation (question 8), from the FLARE-RA questionnaire, and HAQ were recorded at every visit (v=5).

Missingness on previously mentioned variables was handled with multiple imputation (100 imputations). Pain and fatigue were re-scaled from their original Likert scale of 1-6 to 0-100 to match CareRA data. Next, timepoint clustering was removed with multiple outputation (1000x) and each of the 100 000 datasets was analyzed by EFA with principal component extraction and oblimin rotation. The analyses were combined after re-ordering the factors by maximizing factor congruence.

Results:

Sixty-six patients with a mean disease duration of 14.8 years (SD 9.03), mean age of 55.21 years (SD12.87), 96% (63/66) positive to RF or ACPA, 77% (51/66) with erosions and 68% (45/66) female were included in this analysis.

Table 1 provides the results of the EFAs from CareRA and TapERA. The factor structure and factor components remained the same in both datasets. The factor loadings, indicating how strongly a variable relates to its factor (correlation between observed and latent score), were also comparable. The HAQ, however; did have a stronger factor loading in TapERA (0.57 vs 0.92).

Table 1.

Results from the exploratory factor analyses in CareRA and TapERA

VariableCareRATapERAPRFCFLFPRFCFLFFatigue0.900.80PaGH0.870.81Pain0.860.75HAQ0.570.92SJC280.920.82TJC280.890.84PhGH0.760.60CRP0.870.85ESR0.780.82

Factor loadings presented (correlation between the observed score and the latent factor). Cross-loadings were negligible (<0.3) -not presented. The factor order is by % of variance explained.

PRF: patient-reported factor, CF: clinical factor, LF: laboratory factor, PaGH: patient’s global health assessment, HAQ: health assessment questionnaire, SJC28: 28 swollen joint count, TJC28: 28 tender joint count, PhGH: physician’s global health assessment, CRP: C-reactive protein, ESR: erythrocyte sedimentation rate

Conclusion:

The latent factor structure for disease burden originally found in CareRA was successfully validated in the TapERA dataset, underlining the robustness of the PRF, CF and LF scores. HAQ seems to take “greater importance” on established RA. However, deviations in factor loadings (e.g., HAQ) could be attributed to differences between study populations (e.g., early vs. established RA, sample size). Apart from traditional clinical and laboratory factors, patient-reported pain, fatigue, functionality and overall well-being determine disease burden, both in early and established RA. Using these factor scores could facilitate detection and management of patient’s unmet needs.

References:

[1]Pazmino, et al. Does Including Pain, Fatigue, and Physical Function When Assessing Patients with Early Rheumatoid Arthritis Provide a Comprehensive Picture of Disease Burden? J Rheumatology 2020 Nov.

[2]Berthelot JM, et al. A tool to identify recent or present rheumatoid arthritis flare from both patient and physician perspectives: the ‘FLARE’ instrument. Annals Rheumatic Diseases. 2012.

Disclosure of Interests:

None declared

POS1434 WHICH PROGNOSTIC FACTORS MIGHT PREDICT THE NEED FOR TREATMENT ADAPTATION IN EARLY RHEUMATOID ARTHRITIS? A COMPARISON OF MACHINE LEARNING, SURVIVAL ANALYSIS AND REGRESSION METHODS

Background:

Current EULAR guidelines recommend treating RA early, intensively and to-target. A data-driven tool for planning the optimal moment for subsequent visits might adapt visit schedules more to the patient’s needs, without losing treatment quality.

Objectives:

To determine the optimal statistical model and clinical factors to predict the time to a treatment adaptation in early RA patients.

Methods:

This study included 379 patients from the treat-to-target Care in Rheumatoid Arthritis (CareRA) trial. The CareRA protocol included 2 predefined treatment adaptation steps for patients not reaching low disease activity (DAS28CRP<3.2). The 1st adaptation was an MTX dose increase and the second one was adding/increasing the dose of a 2nd csDMARD. Three predictive models (Cox Proportional Hazards, Linear Multi-Task Regression and Random Survival Forest) were trained and validated to predicting time until these 2 adaptations. Factor selection for these models was performed by applying Cox Proportional Hazards with LASSO penalty to each set of demographic and clinical variables recorded at baseline, w4 and w8. Models used these factors at these 3 time points to predict future treatment adaptations. Model performance was estimated by the Uno Concordance Index with five-fold cross-validation. Missing data were imputed by interpolation or mean score.

Results:

Factors selected to predict the first per protocol change included TJC, SJC, HAQ, CRP, pain and morning stiffness>15min. Factors selected to predict the second per protocol change included TJC, SJC, PGA, PhGA. Uno Concordance indices showed similar scores per different statistical model but higher scores at w4 and w8 compared to baseline indicating a better predictive performance (Table 1. next page).

Table 1.

Uno Concordance Scores. Format ‘mean (min-max)’.

BaselineWeek 4Week 8Cox Proportional HazardsChange 10.63 (0.59-0.69)0.72 (0.68-0.80)0.75 (0.69-0.82)Change 20.58 (0.50-0.66)0.75 (0.65-0.87)0.78 (0.65-0.93)Linear Multi-Task RegressionChange 10.65 (0.62-0.68)0.72 (0.68-0.78)0.75 (0.69-0.79)Change 20.58 (0.51-0.68)0.72 (0.67-0.82)0.77 (0.68-0.89)Random Survival ForestChange 10.64 (0.58-0.67)0.71 (0.66-0.78)0.76 (0.68-0.80)Change 20.56 (0.50-0.68)0.72 (0.60-0.82)0.77 (0.64-0.92)

Conclusion:

Our data-driven approach identified predictive clinical factors with a high face validity including joint counts, functionality scores and global health indicators. The different model approaches did not seem to increase the predictive capacity performance. However, our results underline that not so much the baseline disease status but rather the early response to initial treatment reflected in the selected predictive factors can be used for prediction of the need for further treatment adaptation. These models will have to be enriched with patient reported outcomes to further improve predictive performance.

Disclosure of Interests:

None declared

POS0503 THE DISCORDANCE BETWEEN PATIENT-REPORTED AND CLINICAL/BIOLOGICAL OUTCOMES COULD HELP IN PREDICTING FUTURE DISEASE IMPACT IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

Treatment of Rheumatoid Arthritis (RA) has improved significantly based on early treat-to-target (T2T) strategies. Still, decreased health related quality of life (QoL), restricted ability to work and other unmet needs are reported by RA patients even in the absence of disease activity. We previously identified 3 factors representing the broader impact of RA using exploratory factor analysis: a patient-reported factor (patients global health, pain, fatigue and HAQ), a clinical factor (physician’s global health, tender and swollen joint count), and a laboratory factor (ESR and CRP)1.

Objectives:

To test whether the discordance between patient-reported (PRF) and clinical(CF)/laboratory(LF) measures can predict QoL, or has a mediating effect in predicting future disease burden based on disease activity (DAS28CRP).

Methods:

This is a post-hoc analysis of the 2-year CareRA trial. PRF, CF and LF scores were calculated as weighted (by factor loading) sum of their components at week 16, 52 and 104 after treatment initiation. A discordance score (DS) between PRF and the mean of the other two scores was also computed.

Mediation analyses were fitted to test the hypothesis (Figure 1) that DS could be a mediator for predicting PRF, CF and LF at a future time point (week 16, 52 and 104) using DAS28CRP at a previous time point (baseline and week 16). Confidence intervals were estimated via 10 000 bootstraps. Finally, a linear regression was fitted for DS to predict future QoL (RAQoL questionnaire; range 0-30; higher values indicating worse QoL).

Results:

Patients with early RA (n=379) were included with a mean (SD) age of 53.9 (13.0), 77% seropositive and 69% women.

The DS was shown to be mediating the effect of DAS28CRP on any future PRF (Table1). On the other hand, there was no mediation effect of the DS in the prediction of the CF and an inconsistent mediation effect when predicting the LF.

Moreover, the DS at week 16 significantly predicted (p<0.0001) RAQoL scores at year 1 with an effect of β 19.05 (SE 1.58) and an R2 of 0.30 (CI 0.22-0.38). Similarly, it predicted RAQoL (p<0.0001) at year 2 with a β 19.74 (SE 1.56) and R2 of 0.32 (CI 0.24-0.40).

Table 1.

Results of mediation analyses for prediction of future burden based on previous DAS28CRP and mediated by discordance.

TimepointPredictor variablesDirect Effect95% CIsR2Mediation effect Patient-reported factorW16DAS28CRP at BL-0.0091-0.0240, 0.00580.1450PresentDS at BL0.0246*0.0169, 0.03310.1784W52DAS28CRP at W160.0215*0.0010, 0.04190.3394PartialDS at W160.0580*0.0442, 0.07390.2749W104DAS28CRP at W160.0101-0.0102, 0.03050.2798PresentDS at W160.0528*0.0396, 0.06860.2749Clinical factorW16DAS28CRP at BL0.0153*0.0074, 0.02320.0599AbsentDS at BL0.0019-0.0010, 0.00480.1784W52DAS28CRP at W160.0365*0.0267, 0.04630.1944AbsentDS at W160.0034-0.0031, 0.00950.2749W104DAS28CRP at W160.0115*0.0024, 0.02070.0409AbsentDS at W160.0033-0.0019, 0.00890.2749Laboratory factorW16DAS28CRP at BL0.0063*0.0015, 0.01110.0634PartialDS at BL0.0030*0.0012, 0.00500.1784W52DAS28CRP at W160.0003-0.0063, 0.00680.0305PresentDS at W160.0051*0.0012, 0.00960.2749W104DAS28CRP at W16-0.0007-0.0079, 0.00640.0014AbsentDS at W160.0013-0.0019, 0.00460.2749

W: week BL: baseline DS: discordance score

DAS28CRP: disease activity score in 28 joints with C-reactive protein

*p<0.01

Conclusion:

Early discordance between patient-reported and biological/clinical factors mediates the effect of disease activity on future patient-reported outcomes, but also predicts QoL. Paying attention to this early discordance might provide opportunities to prevent patient’s unmet needs by additional non-pharmacological interventions, hence broadening the scope of T2T.

References:

[1]Pazmino S, et al. Does Including Pain, Fatigue, and Physical Function When Assessing Patients with Early Rheumatoid Arthritis Provide a Comprehensive Picture of Disease Burden? J Rheumatol. 2020 Nov 15:jrheum.200758. doi: 10.3899/jrheum.200758. Ahead of print.

Disclosure of Interests:

None declared

POS0266-HPR PATIENT-PERCEIVED ASPECTS OF RA FLARE EVOLVE OVER TIME, AS REFLECTED BY THE FLARE-RA QUESTIONNAIRE: POST-HOC ANALYSIS OF TAPERA

Background:

Flares are common in rheumatoid arthritis (RA). While flares negatively impact clinical and patient-reported outcomes, different aspects of disease activity may constitute a flare to patients. Flare Assessment in RA (FLARE-RA) is a patient-reported questionnaire aiming to detect active or recent RA flares (1). During its validation, arthritis and general health subscales were identified and the instrument was adapted from 13 questions (1-6 Likert scale) to 11 questions (0-10).

Objectives:

To investigate which patient-perceived aspects of flare are assessed by FLARE-RA in the context of a TNFi-tapering trial, using exploratory factor analysis (EFA).

Methods:

Patients with RA in DAS28CRP/ESR-remission (≥6 months) and treated with etanercept 50 mg weekly (≥1 year) were included in the 12-month TapERA (Tapering Etanercept in Rheumatoid Arthritis) trial between 2012 and 2014. Participants completed 3-monthly FLARE-RA questionnaires.

The first and final follow-up visits (M3 & M12) were analyzed. Missing data were imputed with multiple imputation (n = 10). Sampling adequacy was assessed by Kaiser-Meyer-Olkin (KMO) and correlations between variables were evaluated with Bartlett’s sphericity test. Spearman correlation matrices were constructed in each of the 10 imputed datasets. The pooled matrix was then analyzed by EFA with principal component extraction and promax-rotation. EFA aims to identify clusters of questions that elicit similar responses because of association with the same underlying latent (not observable) constructs/factors.

Results:

Sixty-six patients (68% female) with a mean age of 55 years (SD 13) and a mean disease duration of 14.8 years (SD 9) completed a total of 330 FLARE-RA questionnaires. Sampling adequacy was acceptable (KMO = 0.94) and correlation between items was sufficient for factor analysis (p < 0.001).

Table 1 shows the results of EFA in TapERA compared to the validation study (1). Factor loadings indicate how strongly each item correlates with its underlying factor. EFA of the full 13-item FLARE-RA at M3 revealed 3 factors: Arthritis, General health and a Medication factor relating to management of flare. The Arthritis factor explained the largest proportion of variance (31%). EFA at M12 showed the same underlying factors, but a less robust factor structure (cross-loadings >0.3) and a larger proportion of variance explained by the General health factor (33%).

Conclusion:

FLARE-RA assessed similar patient-perceived aspects of RA flare within the context of a TNFi-tapering trial when compared to the validation study, including a Medication factor reflecting use of both glucocorticoids and analgesics. This underlines the usefulness of FLARE-RA in providing a multi-faceted view of patients’ conceptions of RA flare. However, these aspects and their relative importance do seem to evolve over time. Further research is needed to assess if this is due to the influence of time or specific to the studied population/tapering setting.

References:

[1]Fautrel B, et al. Validation of FLARE-RA, a Self-Administered Tool to Detect Recent or Current Rheumatoid Arthritis Flare. Arthritis Rheumatol. 2017;69(2):309–19

Table 1.

Factor loadings (>0.3) from exploratory factor analysis of the 13-question FLARE-RA collected in TapERA, compared to results from the FLARE-RA validation study (1). Factors presented in descending order of % variance explained. Q5 & Q7 were removed in the final FLARE-RA.

ITEMFLARE-RA ValidationTapERA M3TapERA M12GFAFAFGFMFGFAFMFQ1: stiffness0.330.750.930.73Q2: pain0.470.650.911.00Q3: swelling0.350.800.920.93Q4: nocturnal pain0.390.820.670.76Q5: overall0.390.840.860.86Q6: analgesics0.360.810.680.470.51Q7: glucocorticoids0.910.96Q8: fatigue0.680.510.700.87Q9: limitation0.730.480.300.750.74Q10: irritability0.850.390.770.69Q11: mood0.830.440.970.79Q12: withdrawal0.900.891.06Q13: needing help0.810.380.720.600.30Variance explained (%)6610313112333110

AF = arthritis factor, GF = general health factor, MF = medication factor

Disclosure of Interests:

None declared

POS1433 IMPACT OF RHEUMATOID ARTHRITIS ON STRESS: A SYSTEMATIC SCOPING REVIEW

Background:

The literature about the impact of Rheumatoid Arthritis (RA) on mental health is mostly focused on depression and anxiety. Yet, patients can experience stress without depressed mood or anxiety.

Objectives:

To examine the impact of RA on psychological stress excluding depression and anxiety focusing on 3 questions: 1) What is the stress level of RA patients compared to a control group? 2) Which types of stress do RA patients experience? 3) Which are risk factors to develop stress as an RA patient?

Methods:

Four scientific databases, EMBASE, PubMed (including MEDLINE), Web of Science Core Collection and Cochrane Library, were systematically searched from inception until 19/04/2020. Eligible studies included psychological stress in RA patients as outcome. Two reviewers (CV&AVB) independently screened titles and abstracts, and later full texts for eligibility. Full-text screening excluded studies without a separate RA population, with a focus on only anxiety and/or depression or not answering at least 1/3 research questions. Quality was appraised by MINORS/AXIS tools.

Results:

From 11 115 potentially relevant studies, 16 studies met the inclusion criteria (Table 1). Remarkably, 13 different stress measurement instruments were picked-up in this review. Work stress and interpersonal stress seem more prevalent in RA patients compared to healthy controls. Stress at disease onset was more prevalent in RA compared to osteoarthritis. Psychological stress was higher in patients with chronic pain compared to RA. Role stress, social stress and work stress were induced by RA. More disability, more pain, less social support, lower income, younger age and personality factors like excessive worrying, pessimism, and sensitivity to anxiety, seem to increase the risk for increased stress levels.

Table 1.

Included Studies

First AuthorYearCountryPopulationAgeMean ±SDStress InstrumentQuality AssessmentBugajska2010PolandN=437 PolishN=137 German>50y (71%)>50y (38%)SF36v2AXIS: 16/20Coty2017USAN=8054y ±12yRCQWAXIS: 17/20Cunha2016PortugalN=8058yDASS-21AXIS: 10/20Goulia2015GreeceN=16855y ±13ySCL-90RMINORS: 11/16Latman1996USARA, N=128OA, N=7956y63ySRRSAXIS: 20/20Mancuso2006USARA, N=122HC, N=12249y ±12y49y ±12yDUSOCSMINORS: 20/24Nyklicek2015The NetherlandsN=20157y ±12yPSSMINORS: 13/16Persson2005SwedenN=15852ySCL-90RMINORS: 12/16Rahim2018MalaysiaN=18952y ±11yDASS-21AXIS: 17/20Rice2017CanadaRA, N=226CP, N=22958y ±15y45y ±12yDASS-21AXIS: 17/20Rice2016CanadaRA, N=163CP, N=16756y ±13y45y ±11yDASS-21AXIS: 18/20Richter2018GermanyRA, N=163HC, N=16748y ±10y43y ±10yERIAXIS: 17/20Smith2002USARA, N=93OA, N=82HC, N=80RA, 62yOA, 65yHC, 62y1 question probing stressMINORS: 17/24Treharne2007UKN=13455yPSSMINORS: 11/16Turner-Cobb1998UKRA, N=13CP, N=2442y ±8y39y ±4yLEI/HUSMINORS: 17/24Zautra1997USAN=4155y ±10yISLEMINORS: 12/16

Conclusion:

This scoping review is to our knowledge the first to address the heterogeneity of measurement tools and definitions of stress in RA research. It provides the basis for further research, which is needed to predict different stress trajectories and respond to these with patient-centered interventions.

Disclosure of Interests:

None declared

POS0300 DOES COGNITIVE BEHAVIORAL THERAPY IMPROVE PSYCHOSOCIAL OUTCOME IN RHEUMATOID ARTHRITIS: A SYSTEMATIC LITERATURE REVIEW

Background:

Rheumatoid arthritis (RA) is a chronic inflammatory auto-immune disease impacting both physical and mental wellbeing of patients. Cognitive behavioral therapy (CBT), a psycho-social intervention aiming to revert maladaptive thinking and dysfunctional behavior, could improve psychosocial wellbeing in patients with RA. However, it is unclear which CBT components are most successful in improving wellbeing and if certain subpopulations might be more sensitive to CBT therapy.

Objectives:

To summarize in a systematic literature review, the effect of CBT on psychosocial outcomes in RA, focussing on most successful components and which patient subgroups benefit most from CBT.

Methods:

A search was conducted with the support of a health sciences librarian at the KU Leuven Biomedical Library from inception until 28.06.2020 in 5 electronic databases: PubMed, EMBASE, Web of Science Core Collection, Cochrane Library and Cumulated Index to Nursing and Allied Health Literature (CINAHL). We included studies in English and Dutch involving patients >18 years old with RA, using cognitive behavioral approaches as intervention, with outcomes related to psychosocial variables. Two reviewers (CV&AVB) independently screened first the titles and abstracts of the studies, and later the full texts for eligibility. A third reviewer (DDC) was consulted if no consensus was found. Quality was assessed by the Critical Appraisals Skills Programme (CASP) RCT checklist.

Results:

In total, 18 of 1114 retrieved articles could be included (Table 1). Mean age of the participants ranged between 48-63 years with a mean disease duration between 13-16 years. The most used CBT techniques included relaxation training, attention diversion strategies, problem solving skills, goal setting, communication, and social skills training. CBT resulted in ameliorated psychosocial wellbeing related to more active coping styles, improved self-efficacy and reduced perception of disease stressors. Six/18 studies focused on a Ra patient subgroup with an increased psychosocial risk profile, such as high levels of depression. There was limited evidence for an improved treatment effect in these patients because of the elevated levels of psychological distress, but internal motivation seemed key for success.

Table 1.

Included studies

First AuthorYearCountryPopulationMean ageOutcomes assessedO`Leary1988USAN=3049ySelf-efficacy, Depression, Loneliness, perceived stressRadojevic1992USAN=5954yDepression, Anxiety, Pain copingGermond1993SAN=2449yCoping, Health Control, Stress, Mood, ImpactParker1995USAN=14160yLife stress, Daily stressors, helplessness, depression, anxiety, self-efficacy, impactKraaimaat1995NLN=4357yAnxiety, Depression, Social Support, Pain CopingSharpe2001UKN=5556yAnxiety, Depression, CopingEvers2002NLN=6454yAnxiety, Negative mood, Social functioning, Illness cognitions, coping, pain, complianceParker2003USAN=5456yDepression, Stressors, Stress, Anxiety, Helplessness, Self-efficacyVan Lankveld2004NLN=5850yDepression, Anxiety, Stressors, Coping, Social SupportZautra2008USAN=14252yAffect, Depression, Coping, Pain, CatastrophizingHammond2008UKN=16755ySelf-efficacy, distress, Control, Self-ManagementBarsky2010USAN=16853yDistressHewlett2011UKN=11760yAnxiety, Depression, FatigueSharpe2012AUN=10456yAnxiety, DepressionGarnefski2013NL, BEN=8248yDepression, Anxiety, Self-efficacyLumley2014USAN=26655yAnxiety, DepressionVermaak2015AUN=11354yDepression, Anxiety, Self-Efficacy, Distress, QoLHewlett2019UKN=31963yFatigue, Mood, QoL, Self-Efficacy, Helplessness

Conclusion:

Adding CBT to standard care induces modest improvements in psychosocial outcomes for patients with RA. CBT seems more successful if patients are motivated to reflect on their cognitions and behaviours. However, more research with large-scale studies, focusing also on the critical early disease phase, is needed to investigate the long-term benefits of CBT.

Disclosure of Interests:

None declared

Pharmacological modulation of GABAA receptors

Ligand-gated ion channels are integral membrane proteins that activate through a change in conformation upon transmitter binding and were identified as key players of brain function. GABA_A receptors are major inhibitory ligand-gated ion channels of this protein family. They are the target of many therapeutic compounds widely used in the clinic and continue to attract the attention of academic and pharmaceutical laboratories. Advances in the knowledge of the structure of GABA_A receptors at the molecular level with unprecedented resolution enabled the determination of the binding sites of many allosteric modulators revealing the nature of their interactions with the receptors. Herein, we review the latest findings on allosteric modulation of GABA_A receptors and their relevance to drug discovery.

Is intraoperative heparin during renal transplantation useful to reduce graft vascular thrombosis?

OBJECTIVES

The standard treatment for end-stage renal disease is renal transplantation. As vascular anastomoses are performed during the surgery, it may expose to a risk of vascular thrombosis. This raises the question of using intravenous heparin during the procedure. The purpose of this study was to compare the incidence of renal transplant vascular thrombosis in the perioperative period based on whether the patients received or not intraoperative heparin.

METHODS

A single center retrospective study was conducted on a cohort of consecutive patients who underwent renal transplantation between 2011 and 2015. Patients were divided into two groups: patients not receiving heparin vs. receiving heparin at the dose of 0.5mg/kg. A Doppler ultrasound was performed at day one postoperatively to assess the occurrence of vascular thrombosis. Hemorrhagic complications and the need for postoperative transfusion were also assessed.

RESULTS

In total, 261 patients were included. Fifty-one patients received heparin (19.5%). Patient's baseline characteristics were comparable between the groups. No significant difference was found regarding the incidence of vascular thrombosis (6% for both groups, P=1). In addition, no difference was found regarding hemorrhagic complications requiring surgical revision (P=1) as well as early postoperative transfusion rate (P=0.57).

CONCLUSIONS

Our results suggest that intraoperative IV heparin doesn't improve the risk of vascular thrombosis following renal transplantation. However, intraoperative IV heparin was not significantly associated with a higher rate of hemorrhagic complications suggesting that heparin can be safely used if required in some selected patients at higher risk of thrombosis.

LEVEL OF EVIDENCE

3.

A systematic review on the effect of DMARDs on fertility in rheumatoid arthritis

INTRODUCTION

Drug therapy could alter fertility in patients with rheumatoid arthritis (RA). We aimed to perform a systematic review to evaluate if Disease-modifying antirheumatic drug (DMARD) therapy influences fertility as this is an important point to consider in shared decision making on RA therapy.

METHODS

A search was conducted at 18/10/2019 in EMBASE, PubMed (including MEDLINE) and the Web of Science Core Collection. Our inclusion criteria were studies involving women or men diagnosed with RA, older than 18 years and on DMARD therapy, with as outcome a fertility parameter. Systematic reviews, meta-analyses, case reports, case series and animal studies were excluded. Studies not in English or Dutch or published before 2004 were excluded. Quality appraisal was performed by the CASP systematic review checklist.

RESULTS

After duplicate removal, 9030 references were identified. After title/abstract screening, 82 articles remained. After full text screening, 4 articles could be retained. No studies were found through backward snowballing. Only studies involving women could be retained. The included studies investigated the effect of methotrexate, certolizumab pegol, etanercept and sulfasalazine on fertility. No detrimental effects of these DMARDs on time-to-pregnancy, anti-Müllerian hormone serum level or presence of a history of infertility, were reported.

CONCLUSION

This systematic review underlines the gap in knowledge regarding the effect of DMARDs on fertility in women and especially men with RA. DMARD treatment, contrary to general belief, seemed to have no harmful effect on fertility, possibly because it resulted in better controlled disease activity. More research is needed to improve guidance for patients with RA with a child wish.

FRI0035 THE CHALLENGE OF ASSESSING WELL-BEING IN PATIENTS WITH EARLY RHEUMATOID ARTHRITIS

Background:

Advances in therapeutics and treatment strategies for Rheumatoid Arthritis (RA) have improved clinical outcomes. Although these advances also impact the well-being as shown in many patient-reported outcomes, still a sizeable number of patients in clinical remission report a reduced well-being.

Objectives:

To explore factors that contribute to well-being in patients with early RA.

Methods:

Patients from the 2-year pragmatic treat-to-target Care in Early Rheumatoid Arthritis (CareRA) trial were included. Patients were treated intensively, with a combination of csDMARDs and glucocorticoid remission induction schemes, except one group treated with MTX monotherapy.

Eight different validated questionnaires including the Arthritis Self-Efficacy Scale (ASES), the multidimensional Fatigue Inventory (MFI), the Pittsburgh Sleep Quality Index (PSQI) the Revised Illness Perception Questionnaire (IPQ-R), the Utrecht Coping List (UCL), the Short Form 36 (SF-36), RA Quality of Life questionnaire (RA-QOL) and the Social Support List (SSL) were taken. Questionnaires were obtained at baseline, at week 16, 52 and 104 except for the IPQ and UCL, which were only taken at baseline and week 16.

Three patients` groups were created including all patients, patients in remission (DAS28crp < 2.6) and not in remission. Regression models were constructed to define well-being at week 16, 52 and 104. The Patient Global Assessment (PGA) on a Visual Analogue Scale 0-100 (VAS) was chosen as a proxy for well-being (score 0-100). As predictors, all subscales of the 8 validated questionnaires, summing to 84 variables, with and without the VAS for Pain (VAS-Pain) were used in 18 models (3 patient groups, 3 time points, with/without VAS-Pain) in total. Data reduction used forward, backward and stepwise selection based on the Aikake information criteria. Data was checked for influential observations by Cook’s distance and for multicollinearity by variance inflation factors (threshold = 5). Influential observations were removed one observation every time. Highly correlated variables were deleted by backward selection (α=5%). Missing data was handled by multiple imputation using CART with 15 iterations.

Results:

In total, 379 patients were included. Table 1 gives the number of variables and the associated R2. In the 9 models defining well-being without VAS-Pain, 53 variables were used at least once. Most common variables were bodily pain (n=8) and social function (n=5) of the SF-36, and positive emotions (n=4) of the SSL. In the 9 models with VAS-Pain, 31 variables were used at least once. Most common variables were vitality (n=3) and social function (n=3) of the SF-36, and identity (n=3) of the IPQ-R. Model content was heterogenous regarding patient population and time.

R2and number of variables in each model of well-being

All patientsPatients in remissionPatients not in remissionR2#R2#R2#week 1652%1339%753%6week 16 with VAS-Pain78%469%680%5week 5244%844%757%12week 52 with VAS-Pain84%584%692%2week 10440%1339%862%10week 104 with VAS-Pain81%782%486%11

R2= coefficient of determination, the proportion of the variance in the dependent variable that is predictable from the independent variable(s). # = number of variables selected in regression model

Conclusion:

Well-being is apparently difficult to define uniformly as many factors contribute to it. As already known, well-being, defined by PGA, and VAS-Pain are highly associated, even in patients in remission where pain levels should be theoretically lower. Other well-being definitions could lead to different results and should be further explored.

Disclosure of Interests:

Diederik De Cock: None declared, Tianna Poffe: None declared, Geert Verbeke: None declared, Veerle Stouten: None declared, Sofia Pazmino: None declared, Delphine Bertrand: None declared, Johan Joly: None declared, Rene Westhovens Grant/research support from: Celltrion Inc, Galapagos, Gilead, Consultant of: Celltrion Inc, Galapagos, Gilead, Speakers bureau: Celltrion Inc, Galapagos, Gilead, Patrick Verschueren Grant/research support from: Pfizer unrestricted chair of early RA research, Speakers bureau: various companies

AB1153 ANALGESIC AND ANTI-INFLAMMATORY DRUG USE IN PATIENTS WITH RHEUMATOID ARTHRITIS, PSORIATIC ARTHRITIS AND SPONDYLOARTHRITIS VERSUS CONTROLS IN A BELGIAN GENERAL PRACTITIONER REGISTRY

Background:

Rheumatoid arthritis (RA), psoriatic arthritis (PSA) and spondyloarthritis (SPA) are the most common inflammatory rheumatic diseases. Pain is the hallmark symptom in these conditions and pain relief is ranked first amongst preferred outcomes by patients. Level of analgesic and anti-inflammatory drug use is unknown in these populations in Belgium.

Objectives:

To compare analgesic and anti-inflammatory drug use in patient populations of RA, PSA and SPA versus controls in a General Practitioners (GP) setting in an era of expanding treatment possibilities in rheumatology.

Methods:

Data were obtained from Intego over a 13-year time interval from 1999 to 2012. Intego is a Flemish GP-based morbidity registration network hosted at the Academic Center for General Practice of the KU Leuven, covering 2% of the Flemish general population. Patients classified under the International Classification of Primary Care codes L88 (rheumatoid/seropositive arthritis) and L99 (musculoskeletal disease other) were selected for this study. Experienced rheumatologists verified if the keywords mapped to these codes corresponded to a diagnosis of RA/SPA/PSA. The date of these diagnoses in Intego was considered “baseline”. Controls were matched on age, gender, baseline date and GP practice in a 4:1 case ratio. Intego registers all electronic drug prescriptions by the GP. Anytime use of glucocorticoids, NSAIDs, opioids except tramadol, tramadol and paracetamol in the first 3 years after diagnosis is presented. Proportions of patients and controls on analgesic and anti-inflammatory drugs were compared by Chi-Square analyses.

Results:

Over a 13-year period, 738, 229 and 167 patients were included with a diagnosis of RA, SPA or PSA, respectively. Table 1 presents the medication use of these populations. The three conditions had statistically significantly more prescriptions for all types of analgesic and anti-inflammatory drugs compared to controls. Approximately 70% of patients with an inflammatory rheumatic condition received mild pain medication (NSAIDs, Tramadol and Paracetamol) in the first three years after diagnosis. To note is the high use of opioids, even excluding tramadol, in these populations ranging up to 15%.

Table 1.

3-year analgesic and anti-inflammatory drug use in RA, SPA and PSA patients versus controls

MedicationRARA ControlSPASPA ControlPSAPSA ControlNumber of patients7382952229916167668Glucocorticoids241(33%)348(12%)29(13%)70(8%)47(28%)67(10%)NSAIDs455(62%)1156(39%)161(70%)340(37%)114(68%)267(40%)Opioids109(15%)263(9%)31(14%)53(6%)24(14%)45(7%)Tramadol87(12%)150(5%)22(10%)28(3%)16(10%)26(4%)Paracetamol233(32%)598(20%)63(28%)165(18%)51(31%)141(21%)Total analgesic and anti-inflammatory drug use506(69%)1409(48%)172(75%)407(44%)121(72%)309(46%)

RA= Rheumatoid arthritis, PSA= psoriatic arthritis, SPA= spondyloarthritis. Total analgesic and anti-inflammatory drug is the sum of NSAIDs, Tramadol and Paracetamol. Anytime use of drugs are presented.

Conclusion:

Frequent analgesic and anti-inflammatory drug use in patients with a chronic inflammatory joint condition is to be expected, and underlined by the results of our study. Remarkably is the high use of opioids, even excluding tramadol, in patients with RA, PSA and SPA in an era of effective disease modifiers, as well in the control population. Our data shows that around 9% of the Belgian population receives at least once over a 3-year period an opioid prescription. As our data only registers electronic GP prescriptions, this is likely to be an underestimation of the true prescription proportion. Detailed analyses on dose and duration of analgesic and anti-inflammatory drugs will follow.

Disclosure of Interests:

Sofia Pazmino: None declared, Veerle Stouten: None declared, Patrick Verschueren Grant/research support from: Pfizer unrestricted chair of early RA research, Speakers bureau: various companies, Pavlos Mamouris: None declared, Rene Westhovens Grant/research support from: Celltrion Inc, Galapagos, Gilead, Consultant of: Celltrion Inc, Galapagos, Gilead, Speakers bureau: Celltrion Inc, Galapagos, Gilead, Kurt de Vlam Grant/research support from: Celgene, Eli Lilly, Pfizer Inc, Consultant of: AbbVie, Eli Lilly, Galapagos, Johnson & Johnson, Novartis, Pfizer Inc, UCB, Delphine Bertrand: None declared, Kristien Van der Elst: None declared, Bert Vaes: None declared, Diederik De Cock: None declared

THU0089 TRENDS AND PREFERENCES IN RA CLINICAL SCORES WORLDWIDE

Background:

Different scores are used for patient management in rheumatoid arthritis (RA), including patient characterization such as ACR/EULAR criterion [1], disease activity monitoring by healthcare professionnals such as DAS28 [2], DAS28-CRP [2], CDAI [1], SDAI [3], or by patients such as HAQ-DI [4] or RAPID3 [5]. Most of these scores involve computations that are difficult to perform mentally (such as a square root function). Accordingly, several software tools have been designed over the years to help clinicians and patients compute these scores [6].

Objectives:

This work reports for the first time usage statistics for one of these software tools, the RheumaKit online platform, from 2016 to 2020, showing that it has become a standard tool used worldwide by the rheumatology community. It also investigates the increasing use of repeated measurements, as enabled by that platform. Finally, a comparison between different disease activity scores is proposed, and usage preferences are documented.

Methods:

Until January 2020, RheumaKit online portal has allowed users to compute scores without registering on the portal. In such cases, the computations and results are not stored, yet this activity is tracked by Google Analytics (as per explicit cookie policy). Users may also create an account, enabling storage and retrospective access to the computed results. Such entry recording in the RheumaKit database is only available for healthcare professionnals. The system then allows users to create individual patient files in which multiple scores and timepoints are recorded. These two data sources (Google Analytics and internal database) are used to perform this study: counts and trends are reported over the period ranging from 01 Jan 2016 to 31 Dec 2019.

Results:

RheumaKit online application had been accessed by 7,300 distinct users in 2016; this number has grown to 86,000 distinct users in 2019. User distribution has also evolved: in 2016, users were reported from Russia (13% of the 7,300 users), USA (12.2%), Belgium (9.7% – this figure being explained by the fact that the tool is developed in Belgium), France (7.3%), and UK (7.2%); wereas in 2019, users are from the USA (21.1% of the 86,000 users), France (14.4%), Germany (5.4%), Brazil (5.3%), UK (5.3%). With respect to scores, the usage ranking over 2016-2019 outlines a preference for DAS28-CRP (93,900 computations) followed by HAQ-DI (72,800), DAS28 (63,600), CDAI (56,500), SDAI (42,700), RAPID3 (33,800), and ACR-EULAR2010 (19,800). The tendency in registering scores is also increasing, as the number of registered healthcare professionnals went from 117 on the 1stof Jan 2016 to almost 1,200 on 31 Dec 2019.

Conclusion:

The use of computer-assisted clinical scoring for RA patients is an increasing trend observed worldwide, with dominance in Europe and America. The tendency to perform repeated, longitudinal measurements of these scores for a given patient is also increasing exponentially. DAS28-CRP and HAQ-DI are the most used scores among those available in this study.

References:

[1]Aletaha et al. 2010 Rheumatoid arthritis classification criteria: an American College of Rheumatology/European League Against Rheumatism collaborative initiative. Arthritis Rheum 2010

[2]Prevoo et al. Modified disease activity scores that include twenty-eight-joint counts. Development and validation in a prospective longitudinal study of patients with rheumatoid arthritis. Arthritis Rheum 1995.

[3]Smolen et al. A simplified disease activity index for rheumatoid arthritis for use in clinical practice. Rheumatology (Oxford) 2003

[4]Bruce and Fries. The Stanford Health Assessment Questionnaire: Dimensions and Practical Applications. Health Qual Life Outcomes 2003

[5]Pincus et al. An index of only patient-reported outcome measures, routineassessment of patient index data 3 (RAPID3), in two abataceptclinical trials: similar results to disease activity score (DAS28) andother RAPID indices that include physician-reported measures. Rheumatology 2008.

[6]das-score.nl, DAS28.nl, Rheumakit.com, 4s-dawn.com, …

Disclosure of Interests:

Thibault Helleputte Shareholder of: DNAlytics, Damien Bertrand Employee of: DNAlytics.

FRI0566 THE FLARE-RA QUESTIONNAIRE CAN IDENTIFY OMERACT FLARES IN PATIENTS WITH RHEUMATOID ARTHRITIS INCLUDED IN THE TAPERA TRIAL

Background:

The Flare assessment in rheumatoid arthritis (FLARE-RA) questionnaire has been developed to identify flares in patients with rheumatoid arthritis (RA). The first version was published by Berthelot et al. (2012) and consisted of 13 questions on a Likert-scale of 1-6 ranging from ‘completely untrue’ to ‘completely true’. When the FLARE-RA questionnaire was validated by Fautrel et al., 2 questions were removed, and it was rescaled to 0–10. The questionnaires’ usefulness has been tested in few studies. Further external validation in a well-defined cohort of patients with RA is needed.

Objectives:

To externally validate the FLARE-RA questionnaire and determine cut-offs for identifying a flare in an established RA population in which biologicals are tapered.

Methods:

Patients who were in remission according to the DAS28CRP or ESR (≥6 months) and treated with etanercept 50 mg weekly (≥1 year), were enrolled between 2012 – 2014 in the pragmatic 1-year open-label randomised controlled TapERA (Tapering Etanercept in RA) trial. Patients were randomised to continue etanercept 50 mg weekly or taper to 50 mg every other week. The FLARE-RA questionnaire (version of 2012) was completed every 3 months. Outcomes were based on 3 versions of the questionnaire (13 questions (13q), 11 questions (11q) and 11 questions rescaled (r11q)). Per time point, the average of the answers was calculated to obtain a total score of the FLARE-RA questionnaire. The total scores were compared between patients in remission (DAS28CRP <2.6), low (DAS28CRP ≥2.6 - ≤3.2), moderate (DAS28CRP >3.2 - ≤5.1) and high disease activity (DAS28CRP >5.1) using the Kruskal-Wallis test and between patients with and without a flare according to the OMERACT definition (increase in DAS28 >1.2 compared to baseline or increase in DAS28 >0.6 and current DAS28 ≥3.2) using the Mann-Whitney U test. The total FLARE-RA scores of the different time points were combined to determine the receiver operating characteristics (ROC) curves, the corresponding cut-off values and the area under the curve (AUC) for identifying an OMERACT flare. An AUC of <0.5, between 0.5 and 0.7 and >0.7 stands for having no, moderate and a good predictive value, respectively.

Results:

FLARE-RA questionnaires of 66 patients (68% female, mean ± standard deviation (SD) age of 55 ± 11 years) were collected. The FLARE-RA score (13q) did increase when disease activity increased at month (M) 3 and M12 (p<0.01) (table 1). Patients presenting with an OMERACT flare had a statistically significantly higher total FLARE-RA score (13q) compared to patients without a flare, except at M12 (M3 and M6: p<0.05, M9: p<0.01). The AUC - ROC curve of the FLARE-RA questionnaire (13q) for identifying an OMERACT flare was 0.736 and the cut-off value was 2.3 (1-6 scale). The AUC - ROC curve was the same for the 11q and r11q version, namely 0.727. The cut-off values were 2.4 (1-6 scale) and 2.7 (0-10 scale), respectively (figure 1).

Table 1.

Comparison of the total FLARE-RA scores (13q) between the disease activity groups (DAS28CRP)

RemissionLDAMDAHDAP-valueBLPatients (n)62310FLARE Q1.8 ± 0.81.5 ± 0.31.30.800M3Patients (n)501150FLARE Q2.1 ± 1.03.0 ± 0.93.5 ± 1.40.004M6Patients (n)52590FLARE Q2.1 ± 0.83.1 ± 1.33.1 ± 1.90.057M9Patients (n)481071FLARE Q2.1 ± 0.92.8 ± 1.13.3 ± 1.62.40.079M12Patients (n)52860FLARE Q2.1 ± 1.03.1 ± 0.83.2 ± 1.00.002Figure 1.

ROC curves of the total FLARE-RA scores (13q, 11q and r11q version) for identifying a flare according to the OMERACT definition. FLARE Q is expressed in mean ± SD. M month, FLARE Q FLARE-RA questionnaire 13q, n number, LDA low disease activity, MDA moderate disease activity, HDA high disease activity

Conclusion:

The FLARE-RA scores seem to reliably discern between patients with and without an OMERACT flare. A cut-off of 2.7 on the current questionnaire (r11q) had the optimal sensitivity and specificity to identify an OMERACT flare.

Disclosure of Interests:

Delphine Bertrand: None declared, Veerle Stouten: None declared, Sofia Pazmino: None declared, Diederik De Cock: None declared, Anneleen Moeyersoons: None declared, Rene Westhovens Grant/research support from: Celltrion Inc, Galapagos, Gilead, Consultant of: Celltrion Inc, Galapagos, Gilead, Speakers bureau: Celltrion Inc, Galapagos, Gilead, Johan Joly: None declared, Patrick Verschueren Grant/research support from: Pfizer unrestricted chair of early RA research, Speakers bureau: various companies

Développement professionnel continu (DPC) et émergence de la recertification en France. Évolution législative et commentaires

La formation médicale continue (FMC) est une obligation déontologique et légale en France. L’évaluation des pratiques professionnelles (EPP) a rejoint en 2004 l’obligation d’acquisition des connaissances pour devenir le développement professionnel continu (DPC) en 2009. Actuellement, le dispositif est complet : définition, organisation et validation. Mais l’obligation individuelle pour valider le DPC n’a jamais été appliquée. La recertification prévue par la loi de 2019 ne sera opérationnelle qu’en 2021, au plus tôt. Son pilier essentiel est le DPC. La mission de recertification qui a préparé la loi exclut toutes épreuves de vérification des connaissances. La recertification se fait par une valorisation du parcours professionnel comprenant, outre le DPC, une activité maintenue et régulière, une amélioration de la relation avec le patient, la prise en compte de la santé du médecin et l’absence d’évènements indésirables. L’Ordre veillant sur la compétence des médecins, c’est lui qui reçoit la validation du DPC, comme il recevra celle de la recertification.

FRI0020 CLINICAL TREATMENT RESPONSE STILL DOES NOT MATCH PATIENT REPORTED IMPROVEMENT, EVEN IN EARLY RHEUMATOID ARTHRITIS

Background:

Commonly used disease activity scores in rheumatoid arthritis (RA) include one patient reported outcome (PRO) -the patient’s global health assessment (PGA). Exploratory factor analysis (EFA) was performed on data from the 2 year Care in early Rheumatoid Arthritis (CareRA) trial to explain the evolution of disease burden extracting 3 factors.1

Objectives:

To assess the evolution and relative responsiveness over time of clinical, laboratory and patient assessments included in composite scores, together with other PROs like pain, fatigue and functionality in patients with early RA (≤1 year) treated to target (T2T) within the CareRA trial.

Methods:

DMARD naïve patients with early RA (n=379) were included, randomized to remission induction with COBRA-like treatment schemes (n=332) or MTX monotherapy (n=47) and T2T.

Components of disease activity scores (swollen/tender joint count (S/TJC), C-reactive protein (CRP) or erythrocyte sedimentation rate (ESR), and physician (PhGH) or patient (PGA) global health assessment), pain and fatigue (both on 0-100 scale) and HAQ were recorded at every visit.

Missing data was handled with multiple imputation (n=15). Clustering was removed with multiple outputation (n=1000), then each of the 15 000 datasets was analyzed by EFA with principal component extraction and oblimin rotation. The analyses were combined after re-ordering the factors by maximizing factor congruence. The 3 extracted factors and their individual components (with their loadings) were: 1. Patient containing PGA (0.87), pain (0.86), fatigue (0.90) and HAQ (0.5) 2.Clinical with SJC (0.92), TJC (0.89) and PhGH (0.76) and 3.Laboratory with CRP(0.87) and ESR (0.78).1(Pazmino, ACR 2019 abstract, Table 3)

Afterwards, variables were first normalized to a 0-1 scale, then multiplied -weighted- by the factor loadings previously obtained.1For each Patient, Clinical and Laboratory severity score, the weighted variables belonging to each score were summed together and then re-scaled to 0-1 (higher values suggest more burden).

The percentage (%) improvement from baseline to week 104 and the area under the curve (AUC) across time points were calculated per factor.

Differences in % improvement and AUC were compared between patients not achieving and achieving early and sustained (week 16 to 104) disease activity score remission (DAS28CRP <2.6) with ANOVA. Bonferroni correction was used for multiple testing.

Results:

Severity scores of Patient, Clinical and Laboratory factors improved rapidly over time (Figure 1). In patients achieving sustained remission (n=122), Patient, Clinical and Laboratory scores improved 56%, 90% and 27% respectively. In patients not achieving sustained remission (n=257) the improvement was 32%, 78% and 9% respectively (p<0.001 only for clinical improvement).

Patients in CareRA who achieved sustained remission had an AUC of 15.1, 3.4 and 4.7 in Patient, Clinical and Laboratory scores respectively, compared to 32.3, 10.0, and 7.2 in participants not achieving sustained remission (p<0.001 for all comparisons).

Conclusion:

Patient, Clinical and Laboratory severity scores improved rapidly over time in patients achieving rapid and sustained disease control. However, overall, Patient burden seemed not to improve to the same extent as Clinical burden. Patient’s unmet needs in terms of pain, fatigue, functionality and overall well-being should thus be given more attention, even in patients in sustained remission.

References:

[1]Pazmino S,et al.Including Pain, Fatigue and Functionality Regularly in the Assessment of Patients with Early Rheumatoid Arthritis Separately Adds to the Evaluation of Disease Status [abstract]. ACR. 2019.

Disclosure of Interests:

Sofia Pazmino: None declared, Anikó Lovik: None declared, Annelies Boonen Grant/research support from: AbbVie, Consultant of: Galapagos, Lilly (all paid to the department), Diederik De Cock: None declared, Veerle Stouten: None declared, Johan Joly: None declared, Delphine Bertrand: None declared, Rene Westhovens Grant/research support from: Celltrion Inc, Galapagos, Gilead, Consultant of: Celltrion Inc, Galapagos, Gilead, Speakers bureau: Celltrion Inc, Galapagos, Gilead, Patrick Verschueren Grant/research support from: Pfizer unrestricted chair of early RA research, Speakers bureau: various companies

FRI0023 TREATING EARLY AND INTENSIVELY IS ASSOCIATED WITH LOWER FATIGUE LEVELS ON THE LONG TERM, EVEN IN PATIENTS WITH EARLY RHEUMATOID ARTHRITIS CONSIDERED TO HAVE A FAVOURABLE RISK PROFILE

Background:

Fatigue is reported in up to 90% of patients with established Rheumatoid Arthritis (RA). Fatigue has a large impact on patient`s life and is perceived difficult to manage in many patients. The early disease course could constitute a window of opportunity to tackle fatigue.

Objectives:

To explore that, if RA can be controlled rapidly, complaints of fatigue could be less in the long run, even in patients considered at low risk to develop a severe disease course.

Methods:

Patients with a low risk profile recruited in the 2-year pragmatic Care in Early Rheumatoid Arthritis (CareRA) trial were used in this analysis. This low risk profile was based on the absence of erosions, rheumatoid factor, anti-citrullinated protein bodies or low disease activity status. The low-risk group was randomised to either a tight step-up starting with 15mg MTX weekly in monotherapy (MTX-TSU) or COBRA Slim, consisting of 15 mg MTX weekly and a prednisone step-down scheme starting at 30 mg. Fatigue was measured by the multi-dimensional fatigue inventory (MFI), a self-report instrument consisting of 20 questions with a Likert scale from 1-5 as answer. These 20 questions can be subdivided in five subscales (0-20) of four questions (higher scores indicating higher fatigue levels): general fatigue, mental fatigue, physical fatigue, reduced activity and reduced motivation. General fatigue means the general feeling of being tired. Mental fatigue implicates concentration and memory problems. Physical fatigue implicates a lack of energy and strength. Reduced activity means that patients can do less activities for example on one day. Reduced motivation means that patients don’t want to plan or do things due to lack of motivation. MFI was obtained at baseline, at week 16, week 52 and week 104. Cobra Slim was compared with MTX-TSU by Mann-Whitney-U test. The 5 domains of the MFI of the two groups were compared by a generalized estimating equation (GEE) over 2 years adjusting for baseline MFI domain score and DAS28.

Results:

Of the 90 patients recruited in the low-risk group, 80 (89%) patients completed the MFI at baseline. Randomisation was successful resulting in similar baseline characteristics and MFI levels between Cobra Slim (n=38) and MTX-TSU (n=42). After 2 years of treatment, DAS28CRP levels (Slim 1.9 ±0.8 - MTX-TSU 2.2 ±1.0, p=0.253) and DAS28CRP remission (Slim 81.5% - MTX-TSU 77.1%, p=0.677) did not differ between patients. However, general (Slim 9.8 ±4.1 – MTX-TSU 13.1 ±4.0, p=0.005) and mental (Slim 6.8 ±2.7 - MTX-TSU 10.0 ±4.9, p=0.022) fatigue levels on the MFI were lower in the Cobra Slim group at week 104. GEE analysis confirmed that groups differed in the general (p=0.026) and mental (p=0.013) fatigue scale over 2 years (Figure 1).

Figure 1.

DAS28CRP and MFI General Fatigue score over 2 years between groups

Conclusion:

Patients treated intensively have lower fatigue levels over 2 years compared to patients treated more conservatively, even if disease activity became similar in the two groups over time. This underlines the importance of initiating an optimal intensive treatment even in so called low-risk patients. Moreover, our results show that fatigue is a heterogeneous concept, with different interactions between treatment and type of fatigue. Although our study was limited by a small sample size, the data clearly shows how to improve fatigue levels significantly in early RA.

Disclosure of Interests:

Diederik De Cock: None declared, Amber Nooyens: None declared, Sofia Pazmino: None declared, Delphine Bertrand: None declared, Veerle Stouten: None declared, Johan Joly: None declared, Rene Westhovens Grant/research support from: Celltrion Inc, Galapagos, Gilead, Consultant of: Celltrion Inc, Galapagos, Gilead, Speakers bureau: Celltrion Inc, Galapagos, Gilead, Patrick Verschueren Grant/research support from: Pfizer unrestricted chair of early RA research, Speakers bureau: various companies

THU0214 LONG-TERM EFFECTIVENESS OF METHOTREXATE WITH STEP DOWN GLUCOCORTICOID BRIDGING (COBRA SLIM) VERSUS OTHER CONVENTIONAL DMARD REGIMENS AS INITIAL RA THERAPY: 5-YEAR OUTCOMES OF THE CARERA TRIAL

Background:

The treat-to-target Care in Early Rheumatoid Arthritis (CareRA) trial demonstrated that remission induction with csDMARD combinations and step-down glucocorticoids (GCs) was not superior over methotrexate (MTX) monotherapy with step-down GCs (Cobra Slim) in RA patients with a high-risk profile (1). Moreover, Cobra Slim showed benefit over a tight step-up with MTX in monotherapy (TSU) in RA patients with a low-risk profile.

Objectives:

To compare the long term outcomes up to 5 years of different initial intensive treatment strategies in participants of the CareRA-plus study.

Methods:

In the CareRA trial, patients with DMARD naïve early RA were stratified in a high- or low-risk group based upon the presence of serummarkers, disease activity and erosive status. High-risk patients were randomised to Cobra Classic (MTX+sulphasalazine with highly dosed GC remission induction scheme), Cobra Avant-Garde (MTX+leflunomide with moderately dosed GC scheme) or Cobra Slim. Low-risk patients were randomised to Cobra Slim or TSU. Patients completing this trial were eligible for the CareRA-plus observational study. Here, patients were evaluated 6-monthly over 3 years. Therapy adaptation was left to the treating physician. Efficacy was assessed by DAS28-CRP and HAQ and compared between the originally allocated treatment arms. The 5-year evolution from CareRA baseline of DAS28-CRP and HAQ was assessed via linear mixed models. All adverse events (AEs), considered to be clinically relevant by investigators, and DMARD/GCs therapy were registered.

Results:

Of 322 eligible patients, 252 (78%) were included in CareRA-plus, of which 203 (81%) completed the study. Characteristics and outcomes at the CareRA closing visit (year 2) did not differ between patients entering CareRA-plus or not. DAS28-CRP<2.6 at year 5 in high-risk patients was 72%, 77% and 64% in the Classic, Slim and Avant-Garde group respectively (p=0.403). In the longitudinal analyses, all treatment arms in the high-risk group had comparable DAS28-CRP (p=0.921) and HAQ scores over time (p=0.540). In the low-risk population, 83% of patients in the Slim and 82% in the TSU arm had DAS28-CRP<2.6 at year 5 (p=0.945). Low-risk patients starting Cobra-Slim had lower DAS28-CRP scores over 5 years than those receiving TSU (p= 0.002). HAQ score over time did not differ (p=0.129). In high-risk patients, the total numbers of AEs throughout CareRA-plus, were 70 in 36 Classic, 95 in 48 Slim and 80 in 36 Avant-Garde patients (p=0.182). In the low-risk group there were 18 AEs in 10 Slim and 36 in 17 TSU patients (p=0.048). During the 5-year study, biologics were initiated in 22% of all patients: 23% of Classic, 23% of Slim high-risk, 25% of Avant-Garde, 17% of Slim low-risk, and 15% of TSU patients. At the year 5 visit, 71%, 61% and 50% of high-risk patients were on csDMARD monotherapy (mostly MTX) in Classic, Slim and Avant-Garde respectively. Of the low-risk group, 65% in COBRA-Slim and 62% in TSU were taking a single csDMARD. At the year 5 visit, 9% of all participants received chronic oral GC therapy (>3 months).

Conclusion:

All intensive treatment strategies resulted in excellent long-term clinical outcomes. Initial Cobra Slim therapy showed comparable 5-year effectiveness as Cobra Classic and Avant-Garde in high-risk early RA patients and better efficacy and safety than conservative step up treatment in low-risk patients.

Figure 1.

Mean disease activity by DAS28-CRP or mean functionality by HAQ index scores for high-risk or low-risk patients.

References:

[1]Stouten, V. et al. Effectiveness of different combinations of DMARDs and glucocorticoid bridging in early rheumatoid arthritis: two-year results of CareRA. Rheumatology (Oxford). (2019)doi:10.1093/rheumatology/kez213.

Disclosure of Interests: :

Veerle Stouten: None declared, Rene Westhovens Grant/research support from: Celltrion Inc, Galapagos, Gilead, Consultant of: Celltrion Inc, Galapagos, Gilead, Speakers bureau: Celltrion Inc, Galapagos, Gilead, Diederik De Cock: None declared, Sofia Pazmino: None declared, Johan Joly: None declared, Delphine Bertrand: None declared, Kristien Van der Elst: None declared, Patrick Verschueren Grant/research support from: Pfizer unrestricted chair of early RA research, Speakers bureau: various companies

SAT0028 THE FLARE-RA QUESTIONNAIRE CAN PREDICT FLARES IN PATIENTS WITH ESTABLISHED RHEUMATOID ARTHRITIS PARTICIPATING IN THE TAPERA TRIAL

Background:

The Flare assessment in Rheumatoid Arthritis (FLARE-RA) questionnaire was developed to identify Rheumatoid Arthritis (RA) flares, but it is unknown if this questionnaire can also predict flares.

Objectives:

To identify if the FLARE-RA questionnaire has a predictive capacity for OMERACT flares in patients with established RA participating in a tapering trial.

Methods:

Patients, participating in the 1-year open-label pragmatic randomised controlled TapERA (Tapering Etanercept in RA) trial, were included in the analysis. Patients had to be in DAS28CRP or ESR remission (≥6 months) and treated with etanercept 50 mg weekly (≥1 year). Participants were randomised to continue etanercept 50 mg weekly or to taper to 50 mg every other week.

The FLARE-RA questionnaire was completed every 3 months in the trial. This questionnaire consists of 13 questions on a Likert-scale from 1 to 6 reflecting ‘completely untrue’ to ‘completely true’. Validation by Fautrel et al. leaded to elimination of 2 questions (‘steroid intake’ and ‘overall worsening of RA’) and rescaling to 0-10. Our outcomes were based on these 3 versions of the questionnaire, namely 13 questions (13q), 11 questions (11q) and rescaled 11 questions (r11q). The FLARE-RA questionnaire can be divided in 2 subscales: the FLARE-RA arthritis subscale (questions regarding morning stiffness, night disturbances, joint swelling, joint pain, analgesics) and FLARE-RA general symptoms subscale (questions regarding fatigue, functional limitation, irritability, mood disturbances, withdrawal, need for help).

The total FLARE-RA score was calculated by taking the average of all the questions per time point. A flare was defined according to the OMERACT definition, namely an increase in DAS28CRP > 1.2 compared to baseline or increase in DAS28CRP > 0.6 and current DAS28CRP ≥ 3.2. All the total FLARE-RA scores of the baseline, month 3, 6 and 9 visit were grouped and the mean ± standard deviation (SD) FLARE-RA score was compared between patients with or without an OMERACT flare on the next study visit using the Mann-Whitney U test. Logistic regressions using the total FLARE-RA score to predict an OMERACT flare 3 months later were carried out for the 13q, 11q and r11q versions and the FLARE-RA subscales. Missing data were imputed using expectation maximisation.

Results:

Sixty-six patients (68% female, mean ± SD age of 55 ± 11 years) completed the FLARE-RA questionnaire. This yielded 264 FLARE-RA scores, of which the total mean ± SD FLARE-RA score was 2.1 ± 1.0 and 2.7 ± 1.1 for patients without and with an OMERACT flare on the next study visit, respectively (p<0.01). This was comparable for the 11q and r11q versions (Table 1). For the total FLARE-RA score (13q), the odds ratio of having an OMERACT flare 3 months later is 1.6 (95% confidence interval (CI) 1.2 – 2.2, p=0.004). This was 1.5 (95% CI 1.1 – 2.1, p=0.006) for the 11q and 1.2 (95% CI 1.1 – 1.4, p=0.006) for the r11q version. The odds ratio of having an OMERACT flare on the next visit was 1.5 (95% CI 1.2 – 2.0, p=0.002) and 1.4 (95% CI 1.0 – 2.0, p=0.025) for the arthritis and general symptoms subscale, respectively.

Table 1.

Comparison of overall total FLARE-RA scores between patients with or without an OMERACT flare on the next visit

Questionnaire versionNo OMERACT flare on next visitOMERACT flare on next visitP-valueOverall total FLARE-RA score(mean ± SD)13q2.1 ± 1.02.7 ± 1.10.00211q2.2 ± 1.12.7 ± 1.10.004r11q2.3 ± 2.13.4 ± 2.20.004

Overall total FLARE-RA score was derived by grouping the total FLARE-RA scores of the baseline, month 3, 6 and 9 visit.

Conclusion:

Higher total FLARE-RA questionnaire scores seem to indicate a higher risk of an OMERACT flare 3 months later, regardless of which versions or subscales of the FLARE-RA questionnaire were used. Hence, our findings suggest that the FLARE-RA questionnaire could be used as a predictive tool for flares.

Disclosure of Interests:

Delphine Bertrand: None declared, Diederik De Cock: None declared, Veerle Stouten: None declared, Sofia Pazmino: None declared, Anneleen Moeyersoons: None declared, Johan Joly: None declared, Rene Westhovens Grant/research support from: Celltrion Inc, Galapagos, Gilead, Consultant of: Celltrion Inc, Galapagos, Gilead, Speakers bureau: Celltrion Inc, Galapagos, Gilead, Patrick Verschueren Grant/research support from: Pfizer unrestricted chair of early RA research, Speakers bureau: various companies

Management of forearm bone loss with induced membrane technique

There are very few published studies describing the treatment of segmental bone defects of the forearm using the induced membrane technique. The objectives of this study were to evaluate the time to bone union, the function of the joints above and below the treated bone segment and the patients' quality of life over the long-term. We performed a retrospective study in all patients treated by the induced membrane for a forearm bone defect over at 13-year period. Demographics, bone union, complications, functional outcomes and occupational status were collected. Six patients were included: 2 posttraumatic injuries, 1 osteomyelitis, 1 septic arthritis, 1 aseptic nonunion, 1 tumor. The average defect length was 64mm (48-110). All defects were treated with internal fixation. Bone graft was harvested from the iliac crest in two patients, the femur (using the Reamer Irrigator Aspirator technique) in three patients and the radius in one patient. Five patients achieved bone union after a mean of 4months (3-6). Three complications were observed: 1 radioulnar instability, 1 infection of the fixation device, 1 abscess. At an average 8½ years' follow-up, the pain level on the VAS was 0.6 (0-3), the Mayo Elbow Performance Score was 98 (90-100), the Herzberg score was 108 (85.6-140) and the QuickDASH was 14.9 (2.7-35). All patients returned to work. Using the induced membrane technique avoids the complications associated with vascularized autograft and yields good functional outcome and quality of life.

Fulditoxin, representing a new class of dimeric snake toxins, defines novel pharmacology at nicotinic ACh receptors

BACKGROUND AND PURPOSE

Animal toxins have contributed significantly to our understanding of the neurobiology of receptors and ion channels. We studied the venom of the coral snake Micrurus fulvius fulvius and identified and characterized the structure and pharmacology of a new homodimeric neurotoxin, fulditoxin, that exhibited novel pharmacology at nicotinic ACh receptors (nAChRs).

EXPERIMENTAL APPROACH

Fulditoxin was isolated by chromatography, chemically synthesized, its structure determined by X-ray crystallography, and its pharmacological actions on nAChRs characterized by organ bath assays and two-electrode voltage clamp electrophysiology.

KEY RESULTS

Fulditoxin's distinct 1.95-Å quaternary structure revealed two short-chain three-finger α-neurotoxins (α-3FNTxs) non-covalently bound by hydrophobic interactions and an ability to bind metal and form tetrameric complexes, not reported previously for three-finger proteins. Although fulditoxin lacked all conserved amino acids canonically important for inhibiting nAChRs, it produced postsynaptic neuromuscular blockade of chick muscle at nanomolar concentrations, comparable to the prototypical α-bungarotoxin. This neuromuscular blockade was completely reversible, which is unusual for snake α-3FNTxs. Fulditoxin, therefore, interacts with nAChRs by utilizing a different pharmacophore. Unlike short-chain α-3FNTxs that bind only to muscle nAChRs, fulditoxin utilizes dimerization to expand its pharmacological targets to include human neuronal α4β2, α7, and α3β2 nAChRs which it blocked with IC₅₀ values of 1.8, 7, and 12 μM respectively.

CONCLUSIONS AND IMPLICATIONS

Based on its distinct quaternary structure and unusual pharmacology, we named this new class of dimeric Micrurus neurotoxins represented by fulditoxin as Σ-neurotoxins, which offers greater insight into understanding the interactions between nAChRs and peptide antagonists.

Modulation of the Erwinia ligand-gated ion channel (ELIC) and the 5-HT3 receptor via a common vestibule site

Pentameric ligand-gated ion channels (pLGICs) or Cys-loop receptors are involved in fast synaptic signaling in the nervous system. Allosteric modulators bind to sites that are remote from the neurotransmitter binding site, but modify coupling of ligand binding to channel opening. In this study, we developed nanobodies (single domain antibodies), which are functionally active as allosteric modulators, and solved co-crystal structures of the prokaryote (Erwinia) channel ELIC bound either to a positive or a negative allosteric modulator. The allosteric nanobody binding sites partially overlap with those of small molecule modulators, including a vestibule binding site that is not accessible in some pLGICs. Using mutagenesis, we extrapolate the functional importance of the vestibule binding site to the human 5-HT3 receptor, suggesting a common mechanism of modulation in this protein and ELIC. Thus we identify key elements of allosteric binding sites, and extend drug design possibilities in pLGICs with an accessible vestibule site.

A Review of the Cholinergic System and Therapeutic Approaches to Treat Brain Disorders

Since its identification over a hundred years ago, the neurotransmitter acetylcholine (ACh) has proven to play an essential role in supporting many diverse functions. Some well-characterized functions include: chemical transmission at the neuromuscular junction; autonomic function in the peripheral nervous system; and, sustained attention, sleep/wake regulation, and learning and memory within the central nervous system. Within the brain, major cholinergic projection pathways from the basal forebrain and the brainstem support these centrally mediated processes, and dysregulation of the cholinergic system is implicated in cognitive decline associated with aging and dementias including Alzheimer's disease. ACh exerts its effects by binding to two different membrane-bound receptor classes: (1) G‑protein coupled muscarinic acetylcholine receptors (mAChRs), and (2) ligand-gated nicotinic acetylcholine receptors (nAChRs). These receptor systems are described in detail within this chapter along with discussion on the successes and failures of synthetic ligands designed to selectively target receptor subtypes for treating brain disorders. New molecular approaches and advances in our understanding of the target biology combined with opportunities to re-purpose existing cholinergic drugs for new indications continue to highlight the exciting opportunities for modulating this system for therapeutic purposes.

Differentiating the Pharmacodynamics and Toxicology of Macrolide and Ketolide Antibiotics

This is a review of the macrolide and ketolide field focusing on differentiating the pharmacodynamics and especially the toxicology of the macrolides and ketolides. We emphasize the diversity in pharmacodynamics and toxicity of the macrolides and ketolides, resulting from even small structural changes, which makes it important to consider the various different compounds separately, not necessarily as a class. The ketolide, telithromycin, was developed because of rising bacterial macrolide resistance but was withdrawn postapproval after visual disturbances, syncope, myasthenia gravis, and hepatotoxicity were noted. These diverse adverse effects could be attributed to inhibition of nicotinic acetylcholine receptors. Solithromycin, a later generation ketolide, was effective in treating bacterial pneumonia, but it was not approved by the U.S. Food and Drug Administration owing, in part, to its structural similarity to telithromycin. This Miniperspective describes that structurally similar macrolides/ketolides have clearly mechanistically distinct effects. Understanding these effects could help in developing and securing regulatory approval of a new macrolide/ketolide that is active against macrolide-resistant pathogenic bacteria.

A lipid site shapes the agonist response of a pentameric ligand-gated ion channel

Phospholipids are key components of cellular membranes and are emerging as important functional regulators of different membrane proteins, including pentameric ligand-gated ion channels (pLGICs). Here, we take advantage of the prokaryote channel ELIC (Erwinia ligand-gated ion channel) as a model to understand the determinants of phospholipid interactions in this family of receptors. A high-resolution structure of ELIC in a lipid-bound state reveals a phospholipid site at the lower half of pore-forming transmembrane helices M1 and M4 and at a nearby site for neurosteroids, cholesterol or general anesthetics. This site is shaped by an M4-helix kink and a Trp-Arg-Pro triad that is highly conserved in eukaryote GABA_A/C and glycine receptors. A combined approach reveals that M4 is intrinsically flexible and that M4 deletions or disruptions of the lipid-binding site accelerate desensitization in ELIC, suggesting that lipid interactions shape the agonist response. Our data offer a structural context for understanding lipid modulation in pLGICs.

Receptor variants and the development of centrally acting medications

The progressive changes in research paradigms observed in the largest pharmaceutical companies and the burgeoning of biotechnology startups over the last 10 years have generated a need for outsourcing research facilities. In parallel, progress made in the fields of genomics, protein expression in recombinant systems, and electrophysiological recording methods have offered new possibilities for the development of contract research organizations (CROs). Successful partnering between pharmaceutical companies and CROs largely depends upon the competences and scientific quality on offer for the discovery of novel active molecules and targets. Thus, it is critical to review the knowledge in the field of neuroscience research, how genetic approaches are augmenting our knowledge, and how they can be applied in the translation from the identification of potential molecules up to the first clinical trials. Taking these together, it is apparent that CROs have an important role to play in the neuroscience of drug discovery.


Antagonizing α7 nicotinic receptors with methyllycaconitine (MLA) potentiates receptor activity and memory acquisition

α7 nicotinic acetylcholine receptors (α7nAChRs) have been targeted to improve cognition in different neurological and psychiatric disorders. Nevertheless, no α7nAChR activating ligand has been clinically approved. Here, we investigated the effects of antagonizing α7nAChRs using the selective antagonist methyllycaconitine (MLA) on receptor activity in vitro and cognitive functioning in vivo. Picomolar concentrations of MLA significantly potentiated receptor responses in electrophysiological experiments mimicking the in vivo situation. Furthermore, microdialysis studies showed that MLA administration substantially increased hippocampal glutamate efflux which is related to memory processes. Accordingly, pre-tetanus administration of low MLA concentrations produced longer lasting potentiation (long-term potentiation, LTP) in studies examining hippocampal plasticity. Moreover, low doses of MLA improved acquisition, but not consolidation memory processes in rats. While the focus to enhance cognition by modulating α7nAChRs lies on agonists and positive modulators, antagonists at low doses should provide a novel approach to improve cognition in neurological and psychiatric disorders.