MRI IN EVALUATION OF INFLAMMATORY MYOPATHY

Background: MRI of skeletal muscles has been widely used to assess several types of myopathies, including inherited and acquired muscle diseases. Objectives: To describe current possibilities in use of MRI in diagnostics and assessment of idiopathic inflammatory myopathies (IIMs). Methods: T2 weighted images with fat suppression (T2W/FS) or short tau inversion recovery (STIR) sequence with long time to echo (TE) and T1 weighted images were used to evaluate inflammatory changes (STIR) and muscle atrophy or fat substitution (T1). Simple scoring system was used for correlative studies with histopathological changes. New and more elaborate system for scoring of MR scans was developed and used to evaluate longitudinal images during the therapeutic study. Results: Muscle biopsy guided by positive MRI finding contains significantly more inflammatory cells than the biopsy taken from MRI identified non-affected sites. However, even in parts of muscles, which look unaffected on MR scan, important numbers of the inflammatory cells can be found. It is mainly the signal intensity in MR scan, which is associated with disease activity in the acute presentation of IIMs. Longitudinal follow-up of patients with IIMs showed significant reduction of signal intensity in number of muscles when using new detailed scoring method. Conclusions: Muscle MRI is a useful method to guide the biopsy site in IIMs. Scoring system that uses semiquantitative assessment of individual muscles is sensitive for evaluation of improvement during the treatment. No universal scoring method has been validated and accepted so far for evaluation of inflammation and atrophic changes during IIMs. Developmnet of standard recommendations for muscle MRI assessment in IIMs is very much needed. References: 1. Tomasová Studýnková J, et al. Rheumatology (Oxford) 2007,46:1174–79. 2. Kubínová K, et al. Curr Opin Rheumatol 2017;29:623–31. 3. Kubínová K, et al. Clin Exp Rheumatol 2018;36 Suppl 114(5):74–81

The metastasis-associated protein S100A4 promotes the inflammatory response of mononuclear cells via the TLR4 signalling pathway in rheumatoid arthritis

Objectives. S100A4 has been implicated in cancer and several inflammatory diseases, including RA. The aim of the present study was to determine whether S100A4 can stimulate proinflammatory cytokine production in mononuclear cells. Methods. Peripheral blood mononuclear cells (PBMCs) isolated from patients with RA were stimulated with S100A4, S100A8, S100A9 and S100A12. The production of IL-1β, IL-6 and TNF-α was measured by ELISA. Receptor for advanced glycation end products (RAGEs) and Toll-like receptor 4 (TLR4) signalling were examined. For signalling pathway blocking studies, inhibitors of myeloid differentiation primary response gene 88 (MyD88), nuclear factor kappa B (NF-κB) and the mitogen activated protein (MAP) kinases p38, extracellular signal-regulated kinase 1/2 (ERK1/2) and Jun N-terminal kinase (JNK) were used. MAP kinase activation was evaluated by western blotting. Results. Stimulation of PBMCs with S100A4 significantly up-regulated IL-1β, IL-6 and TNF-α production compared with unstimulated cells (P < 0.001). Importantly, the production of these cytokines was markedly enhanced in response to S100A4 compared with S100A8 and S100A12; however, it was less pronounced compared with S100A9. Furthermore, enhanced production of proinflammatory cytokines in S100A4-stimulated PMBCs was at least partly mediated via TLR4, but not RAGEs, and by activation of the transcription factor NF-κB and the MAP kinases p38 and ERK1/2. Conclusion. This is the first study to demonstrate that S100A4 can induce an inflammatory response mediated by TLR4 and by the activation of NF-κB and the kinases p38 and ERK1/2 in mononuclear cells from patients with RA. Therefore S100A4 may be a potential therapeutic target for immune-mediated disease

The metastasis promoting protein S100A4 is increased in idiopathic inflammatory myopathies

Objectives. The S100A4 protein is known as a metastasis promoting factor; however, its involvement in non-malignant diseases such as RA and psoriasis has been recently described. The aim of this study was to investigate the expression and possible role of S100A4 in idiopathic inflammatory myopathies. Methods. S100A4 protein expression was detected by immunohistochemistry in muscle tissue from control individuals (n = 11) and patients with PM and DM (n = 8/6). IF staining was used to co-localize S100A4 with selected cells. Cytokine expression and protein synthesis in S100A4-treated cells were analysed by RT-PCR and ELISA. Results. S100A4 protein was significantly up-regulated in muscle tissue of patients with inflammatory myopathies compared with control individuals and was associated particularly with the presence of mononuclear infiltrates. Only few regenerating muscle fibres in PM/DM expressed S100A4. Then we analysed the effect of S100A4 on human myocytes and peripheral blood mononuclear cells (PBMCs). Although S100A4 did not affect myocytes, stimulation of PBMCs with S100A4 significantly induced the expression and synthesis of TNF-α, IL-1β and IL-6, but not of IFN-α. We showed that S100A4 is not directly involved in perforin/granzyme B-induced apoptosis and that it does not modulate the expression of Bax and Bcl2 mRNA in myocytes and PBMCs. Conclusion. Increased expression of S100A4 in inflamed muscle tissue highlights its potential role in the pathogenesis of inflammatory myopathies. S100A4 may act as a cytokine-like factor indirectly promoting muscle fibre damage by stimulating mononuclear cells to increase the synthesis of pro-inflammatory cytokine

Long-Term Efficacy and Safety in Patients With Rheumatoid Arthritis Continuing on SB4 or Switching From Reference Etanercept to SB4

Objectives: SB4 (Benepali, Brenzys) is a biosimilar of reference etanercept (ETN). In a randomised, double-blind, 52-week study, SB4 demonstrated comparable efficacy and safety to ETN in patients with rheumatoid arthritis (RA). The open-label extension period evaluated long-term efficacy, safety and immunogenicity when continuing SB4 versus switching from ETN to SB4. Methods: In the randomised, double-blind phase, patients received weekly subcutaneous administration of 50 mg SB4 or ETN with background methotrexate for up to 52 weeks. Patients in the Czech Republic and Poland who completed the 52-week visit were enrolled in the open-label extension period and received SB4 for 48 additional weeks. Efficacy, safety and immunogenicity were assessed up to week 100. Results: Of 245 patients entering the extension period, 126 continued to receive SB4 (SB4/SB4) and 119 switched to SB4 (ETN/SB4). American College of Rheumatology (ACR) response rates were sustained and comparable between SB4/SB4 and ETN/SB4 with ACR20 response rates at week 100 of 77.9% and 79.1%, respectively. Other efficacy results, including radiographic progression, were also comparable between the groups. After week 52, rates of treatment-emergent adverse events were 47.6% (SB4/SB4) and 48.7% (ETN/SB4); one patient/group developed non-neutralising antidrug antibodies. No cases of active tuberculosis or injection-site reactions were reported during the extension period. One patient (SB4/SB4) died of hepatic cancer. Conclusions: SB4 was effective and well tolerated over 2 years in patients with RA. Efficacy, safety and immunogenicity were comparable between the SB4/SB4 and ETN/SB4 groups, showing no risk associated with switching patients from ETN to SB4

52-week results of the phase 3 randomized study comparing SB4 with reference etanercept in patients with active rheumatoid arthritis

Objective: To compare the 52-week efficacy and safety of SB4 [an etanercept biosimilar] with reference etanercept (ETN) in patients with active RA. Methods: In a phase 3, randomized, double-blind, multicentre study, patients with moderate to severe RA despite MTX treatment were randomized to receive 50 mg/week of s.c. SB4 or ETN up to week 52. Efficacy assessments included ACR response rates, 28-joint DAS, Simplified and Clinical Disease Activity Indices and changes in the modified total Sharp score (mTSS). Safety and immunogenicity were also evaluated. Results: A total of 596 patients were randomized to receive either SB4 (n = 299) or ETN (n = 297) and 505 (84.7%) patients completed 52 weeks of the study. At week 52, the ACR20 response rates in the per-protocol set were comparable between SB4 (80.8%) and ETN (81.5%). All efficacy results were comparable between the two groups and they were maintained up to week 52. Radiographic progression was also comparable and the change from baseline in the mTSS was 0.45 for SB4 and 0.74 for ETN. The safety profile of SB4 was similar to that of ETN and the incidence of anti-drug antibody development up to week 52 was 1.0 and 13.2% in the SB4 and ETN groups, respectively. Conclusion: Efficacy including radiographic progression was comparable between SB4 and ETN up to week 52. SB4 was well tolerated and had a similar safety profile to that of ETN. Trial registration number: ClinicalTrials.gov NCT01895309, EudraCT 2012-005026-30

Differences and similarities between the EULAR/ASAS-EULAR and national recommendations for treatment of patients with psoriatic arthritis and axial spondyloarthritis across Europe

This is the first report comparing EULAR and national treatment recommendations for PsA patients across Europe, and the first this decade to compare ASAS-EULAR and national treatment recommendations in axSpA patients. An electronic survey was completed from October 2021-April 2022 by rheumatologists in 15 European countries. One and four countries followed all EULAR and ASAS-EULAR recommendations, respectively. Five countries had no national treatment recommendations for PsA and/or axSpA, but followed other regulations. In several countries, national treatment recommendations predated the most recent EULAR/ASAS-EULAR recommendations. Entry criteria for starting biologic/targeted synthetic disease-modifying anti-rheumatic drugs varied considerably. In several countries, for PsA patients with significant skin involvement, interleukin-17 inhibitors were not given preference. The positioning of Janus Kinase inhibitors differed and Phosphodiesterase-4 inhibitors were not in use/reimbursed in most countries. This study may motivate European countries to update their national treatment recommendations, to align them better with the latest international recommendations

Impact of Upadacitinib on laboratory parameters and related adverse events in patients with RA: Integrated data up to 6.5 years

Introduction: Upadacitinib (UPA) is a Janus kinase inhibitor that has demonstrated efficacy in moderate-to-severe rheumatoid arthritis (RA) with an acceptable safety profile. We investigated laboratory parameter changes in UPA RA clinical trials. Methods: Pooled data from six randomized trials in the SELECT phase 3 program were included. Key laboratory parameters and safety data were measured for UPA 15 and 30 mg once daily (QD), adalimumab (ADA) 40 mg every other week + methotrexate (MTX), and MTX monotherapy. Exposure-adjusted event rates (EAERs) of adverse events were calculated. Results: A total of 3209 patients receiving UPA 15 mg QD (10 782.7 patient-years [PY]), 1204 patients receiving UPA 30 mg QD (3162.5 PY), 579 patients receiving ADA + MTX (1573.2 PY), and 314 patients receiving MTX monotherapy (865.1 PY) were included, representing up to 6.5 years of total exposure. Decreases in mean levels of hemoglobin, neutrophils, and lymphocytes, and increases in mean levels of liver enzymes and creatinine phosphokinase were observed with UPA, with grade 3 or 4 changes observed in some patients. Mean low- and high-density lipoprotein cholesterol ratios remained stable for patients receiving UPA 15 mg QD. EAERs of anemia and neutropenia occurred at generally consistent rates between UPA and active comparators (3.1–4.3 and 1.7–5.0 events [E]/100 PY across treatment groups, respectively). Rates of hepatic disorder were higher with MTX monotherapy, UPA 15 mg and UPA 30 mg (10.8, 9.7, and 11.0 E/100 PY, respectively) versus ADA + MTX (6.4 E/100 PY). Rates of lymphopenia were highest with MTX monotherapy (3.2 E/100 PY). Treatment discontinuations due to laboratory-related events were rare, occurring in 1.1% and 2.2% of patients treated with UPA 15 and 30 mg QD, respectively. Conclusions: The results of this integrated long-term analysis of laboratory parameters continue to support an acceptable safety profile of UPA 15 mg QD for moderate-to-severe RA