Gene-expression analysis of adult-onset Still's disease and systemic juvenile idiopathic arthritis is consistent with a continuum of a single disease entity

[Autoinflammatory diseases associated with IL-18]

Autoinflammatory diseases (AIDs) are conditions characterized by dysfunction of innate immunity, causing systemic inflammation and various clinical symptoms. The field of AIDs has expanded due to improved comprehension of pathophysiological mechanisms and advancements in genomics techniques. A new emerging category of AIDs is characterized by a significant increase in interleukin 18 (IL-18), a pro-inflammatory cytokine synthesized in macrophages and activated by caspase 1 via various inflammasomes. IL-18 plays a role in the regulation of innate and adaptive immunity. IL-18 is involved in various functions, such as the proliferation, survival, and differentiation of immune cells, tissue infiltration of immune cells, polarization of immune responses, and production of other pro-inflammatory cytokines. This review analyzes the literature on IL-18 regarding its functions and its implications in the diagnosis and treatment of AIDs. IL-18-associated AIDs comprise Still's disease and diseases associated with mutations in NLRC4, XIAP, CDC42, and PSTPIP1, as well as IL-18BP deficiencies. With the exception of PSTPIP1-associated diseases, these conditions all carry a risk of macrophagic activation syndrome. Measuring IL-18 levels in serum can aid in the diagnosis, prognosis, and monitoring of these diseases. Therapies targeting IL-18 and its signaling pathways are currently under investigation.

An Unusual Case of Fever in Paralytic Ileus

Still's disease is frequently a condition of exclusion for patients with an unidentified cause of fever. Accompanying symptoms typically include fever, arthralgia, and a transient skin rash. The underlying pathophysiology indicates an autoimmune origin. Diagnosis is primarily clinical, often utilizing the Yamaguchi criteria. The case in question involves a 19-year-old male presenting with high-grade fever and paralytic ileus. The patient received intravenous glucocorticoids and cyclophosphamide, resulting in a rapid clinical improvement. During the follow-up, tofacitinib was initiated based on the clinical response observed.

Defining Criteria for Disease Activity States in Systemic Juvenile Idiopathic Arthritis Based on the Systemic Juvenile Arthritis Disease Activity Score

OBJECTIVE

Our objective was to develop and validate cutoff values in the systemic Juvenile Arthritis Disease Activity Score 10 (sJADAS10) that distinguish the states of inactive disease (ID), minimal disease activity (MDA), moderate disease activity (MoDA), and high disease activity (HDA) in children with systemic juvenile idiopathic arthritis, based on subjective disease state assessment by the treating pediatric rheumatologist.

METHODS

The cutoff definition cohort was composed of 400 patients enrolled at 30 pediatric rheumatology centers in 11 countries. Using the subjective physician rating as an external criterion, six methods were applied to identify the cutoffs: mapping, calculation of percentiles of cumulative score distribution, the Youden index, 90% specificity, maximum agreement, and receiver operating characteristic curve analysis. Sixty percent of the patients were assigned to the definition cohort, and 40% were assigned to the validation cohort. Cutoff validation was conducted by assessing discriminative ability.

RESULTS

The sJADAS10 cutoffs that separated ID from MDA, MDA from MoDA, and MoDA from HDA were ≤2.9, ≤10, and >20.6, respectively. The cutoffs discriminated strongly among different levels of pain, between patients with and without morning stiffness, and among patients whose parents judged their disease status as remission or persistent activity or flare or were satisfied or not satisfied with current illness outcome.

CONCLUSION

The sJADAS cutoffs revealed good metrologic properties in both definition and validation cohorts and are therefore suitable for use in clinical trials and routine practice.

Adult-Onset Still's Disease (AOSD): Advances in Understanding Pathophysiology, Genetics and Emerging Treatment Options

Adult-onset Still's disease (AOSD) is a multisystemic complex disorder clinically characterised by episodes of spiking fever, evanescent rash, polyarthritis or diffuse arthralgias; multiorgan involvement may develop according to the hyper-inflammatory extent. The pathogenesis of AOSD is not completely recognised. The central role of macrophage activation, which results in T helper 1 (Th1) cell cytokine activation, is well established. Pro-inflammatory cytokines such as interleukin (IL)-1, IL-6 and IL-18 play a fundamental role in disease onset and progression. The disease may develop in both children and adults with overlapping clinical features, and although several subsets depending on the clinical manifestations and the cytokines expressed have been identified, the dichotomy between systemic juvenile idiopathic arthritis (sJIA) and AOSD nowadays has been overcome, and the pathology is considered a disease continuum between ages. Various therapeutic approaches have been evaluated thus far, and different compounds are under assessment for AOSD treatment. Historically, glucocorticoids have been employed for treating systemic manifestations of Still's disease, while conventional synthetic disease modifying anti-rheumatic drugs (csDMARDs) demonstrated efficacy in controlling the articular manifestations. Currently, biological (b) DMARDs are widely employed; IL-1 inhibitors such as anakinra and canakinumab have proven to have high efficacy and an excellent safety profile and the anti-IL-6 tocilizumab is approved for sJIA, with several trials and longitudinal studies confirming its efficacy and safety. Moreover, in the light of the 'window of opportunity', new evidence showed that the earlier these treatments are initiated, the sooner clinical inactivity can be achieved. Other treatment options are being considered since several molecules involved in the disease pathophysiology can be targeted through various mechanisms. This review will provide a broad overview of AOSD pathophysiology, insights into specific organ manifestations and the currently available treatments with the identification of potential therapeutic targets involved in AOSD pathogenesis will be outlined.

Diagnosing and Treating Systemic Juvenile Idiopathic Arthritis and Adult-Onset Still's Disease as Part of the Still's Disease Continuum

Aim

We have summarised the existing evidence supporting the concept that systemic juvenile idiopathic arthritis (sJIA) and adult-onset Still's disease (AOSD) are part of the same Still's disease spectrum.

Methods

A PubMed/Embase database search was conducted using specific search strings and free text words to screen for relevant articles. The search was limited to studies in humans, published up to June 2023, in English-language.

Summary

sJIA and AOSD are rare autoinflammatory disorders that have similar pathophysiological and clinical features. The clinical presentations of sJIA and AOSD are highly variable, with differential diagnoses that include a broad range of malignancies, infectious diseases, and autoimmune disorders, which contribute to delays in diagnosis. Several sets of classification exist to help diagnose patients in clinical practice; the International League of Associations for Rheumatology criteria for sJIA and the Yamaguchi and Fautrel criteria for AOSD are the most-used criteria. The therapeutic strategy for Still's disease aims to relieve signs and symptoms, prevent irreversible joint damage and potentially life-threatening complications, and avoid deleterious side effects of treatment. Recently, targeted therapies such as interleukin (IL)-1 and IL-6 inhibitors have become available for the treatment of sJIA and AOSD. While these biologics were originally largely reserved for patients in whom non-steroidal anti-inflammatory drugs, corticosteroids and conventional synthetic disease-modifying anti-rheumatic drugs had failed, they are increasingly used earlier in the treatment paradigm. Among IL-1 inhibitors, canakinumab is the only biologic approved in the US for the treatment of both sJIA and AOSD.

Recent advances and evolving concepts in Still's disease

Still's disease is a rare inflammatory syndrome that encompasses systemic juvenile idiopathic arthritis and adult-onset Still's disease, both of which can exhibit life-threatening complications, including macrophage activation syndrome (MAS), a secondary form of haemophagocytic lymphohistiocytosis. Genetic insights into Still's disease involve both HLA and non-HLA susceptibility genes, suggesting the involvement of adaptive immune cell-mediated immunity. At the same time, phenotypic evidence indicates the involvement of autoinflammatory processes. Evidence also implicates the type I interferon signature, mechanistic target of rapamycin complex 1 signalling and ferritin in the pathogenesis of Still's disease and MAS. Pathological entities associated with Still's disease include lung disease that could be associated with biologic DMARDs and with the occurrence of MAS. Historically, monophasic, recurrent and persistent Still's disease courses were recognized. Newer proposals of alternative Still's disease clusters could enable better dissection of clinical heterogeneity on the basis of immune cell profiles that could represent diverse endotypes or phases of disease activity. Therapeutically, data on IL-1 and IL-6 antagonism and Janus kinase inhibition suggest the importance of early administration in Still's disease. Furthermore, there is evidence that patients who develop MAS can be treated with IFNγ antagonism. Despite these developments, unmet needs remain that can form the basis for the design of future studies leading to improvement of disease management.

Outcomes of Regenerative Endodontic Treatment Performed Using Different Magnification Devices: A Systematic Review

Aim

In this systematic review, we assessed whether the effects of the usage of various devices help with magnification in endodontics and whether they resulted in any significant changes in the clinical result of treatment.

Materials and Methods

An exhaustive search was performed across MEDLINE and Cochrane Registers for various clinical studies, which were focused on comparing regenerative endodontic treatment based on the usage of magnification devices. Various terms were used to search these clinical trials such as microscope, regenerative endodontic surgery, apicoectomy, endoscope, and loupes.

Results

After scrutinizing the studies, around three clinical trials based on magnification in endodontic surgeries were included in the present review. It was observed that no statistically noteworthy betterment of treatment outcome was seen in patients treated with either of the magnification devices such as loupes and microscope.

Conclusion

It was evident that these magnification devices can alter the effectiveness of regenerative endodontic treatment in a very minimal way. However, we believe that more randomized clinical studies should be conducted in this area.

Deep Immunophenotyping of Circulating T and B Cells in Relapsing Adult-Onset Still's Disease

Adult-onset Still's disease (AOSD) is a complex systemic inflammatory disorder, categorized as an 'IL-1 driven' inflammasomapathy. Despite this, the interaction between T and B cells remains poorly understood. We conducted a study, enrolling 7 patients with relapsing AOSD and 15 healthy control subjects, utilizing deep flow cytometry analysis to examine peripheral blood T- and B-cell subsets. T-cell and B-cell subsets were significantly altered in patients with AOSD. Within CD4+ T cells, Th2 cells were decreased. Additionally, Th17 cell and follicular Th cell subsets were altered within CD45RA-CD62L+ and CD45RA-CD62L- Th cells in patients with AOSD compared to healthy controls. We identified changes in CD8+ T cell maturation and 'polarization' in AOSD patients, with an elevated presence of the TEMRA CD8+ T cell subset. Furthermore, the percentage of Tc1 cells was decreased, while the frequency of CCR6-CXCR3- Tc2 cells was elevated. Finally, we determined that the frequency of CD5+CD27- B cells was dramatically decreased in patients with AOSD compared to healthy controls. Further investigations on a large group of patients with AOSD are required to evaluate these adaptive immunity cells in the disease pathogenesis.

Autoantibody-Mediated Depletion of IL-1RA in Still's Disease and Potential Impact of IL-1 Targeting Therapies

BACKGROUND

Adult-onset Still's disease (AOSD) and systemic juvenile idiopathic arthritis (sJIA) resemble a continuum of a rare, polygenic IL-1β-driven disease of unknown etiology.

OBJECTIVE

In the present study we sought to investigate a potential role of recently described autoantibodies neutralizing the interleukin-1(IL-1)-receptor antagonist (IL-1-Ra) in the pathogenesis of Still's disease.

METHODS

Serum or plasma samples from Still's disease patients (AOSD, n = 23; sJIA, n = 40) and autoimmune and/or inflammatory disease controls (n = 478) were analyzed for autoantibodies against progranulin (PGRN), IL-1Ra, IL-18 binding protein (IL-18BP), and IL-36Ra, as well as circulating IL-1Ra and IL-36Ra levels by ELISA. Biochemical analyses of plasma IL-1Ra were performed by native Western blots and isoelectric focusing. Functional activity of the autoantibodies was examined by an in vitro IL-1β-signaling reporter assay.

RESULTS

Anti-IL-1-Ra IgG were identified in 7 (27%) out of 29 Still's disease patients, including 4/23 with AOSD and 3/6 with sJIA and coincided with a hyperphosphorylated isoform of endogenous IL-1Ra. Anti-IL-36Ra antibodies were found in 2 AOSD patients. No anti-PGRN or anti-IL-18BP antibodies were detected. Selective testing for anti-IL-1Ra antibodies in an independent cohort (sJIA, n = 34) identified 5 of 34 (14.7%) as seropositive. Collectively, 8/12 antibody-positive Still's disease patients were either new-onset active disease or unresponsive to IL-1 blocking drugs. Autoantibody-seropositivity associated with decreased IL-1Ra plasma/serum levels. Seropositive plasma impaired in vitro IL-1Ra bioactivity, which could be reversed by anakinra or canakinumab treatment.

CONCLUSION

Autoantibodies neutralizing IL-1Ra may represent a novel patho-mechanism in a subgroup of Still's disease patients, which is sensitive to high-dose IL-1 blocking therapy.

Criteria for Cytokine Storm Syndromes

In the past two decades, there has been a great deal of work aimed to devise diagnostic guidelines, classification criteria, and diagnostic scores for cytokine storm syndromes (CSSs). The most notable effort has been the large-scale multinational study that led to the development of the 2016 classification criteria for macrophage activation syndrome (MAS) complicating systemic juvenile idiopathic arthritis (JIA). Future studies should scrutinize the validity of the proposed criteria, particularly in systemic JIA patients treated with biologics, in children with subtle or incomplete forms of MAS, and in patients with MAS complicating other rheumatologic disorders. More generic CSS criteria are also available but often lack sensitivity and specificity in a wide variety of patient populations and CSSs of different etiologies. The coronavirus disease 2019 (COVID-19)-related lung disease led to an evolution of the concept of a "cytokine storm." Emerging and unsolved challenges in the diagnosis of the different forms of CSSs highlight the need for diagnostic tools and well-established classification criteria to enable timely recognition and correct classification of patients.

The latest advances in the use of biological DMARDs to treat Still's disease

INTRODUCTION

Currently, the therapeutic management of Still's disease, a multisystemic inflammatory rare disorder, is directed to target the inflammatory symptoms and signs of patients. The treatment varies from glucocorticoids to disease-modifying antirheumatic drugs (DMARDs), both conventional synthetic and biological (bDMARDs). Usually, in refractory patients, bDMARDs are administered.

AREAS COVERED

Among bDMARDs, IL-1 and IL-6 inhibitors are frequently used, as data reported from both clinical trials and 'real-life' experiences. Recently, innovative therapeutic strategies have suggested an early administration of bDMARDs to increase the rate of clinical response and drug-free remission. Some new targets have been also proposed targeting IL-18, IFN-γ, and JAK/STAT pathway, which could be applied to Still's disease and its life-threatening evolution.

EXPERT OPINION

Many lines of evidence improved the knowledge about the therapeutic management of Still's disease with bDMARDs. However, many unmet needs may be still highlighted which could provide the basis to arrange further specific research in increasing the rate of clinical response. In fact, Still's disease remains a highly heterogeneous disease suggesting possible diverse underlying pathogenic mechanisms, at least partially, and consequent different therapeutic strategies. A better patient stratification may help in arranging specific studies to improve the long-term outcome of Still's disease.

Kawasaki Disease-Associated Cytokine Storm Syndrome

Kawasaki disease (KD) is a hyperinflammatory syndrome manifesting as an acute systemic vasculitis characterized by fever, nonsuppurative conjunctival injection, rash, oral mucositis, extremity changes, and cervical lymphadenopathy. KD predominantly affects young children and shares clinical features and immunobiology with other hyperinflammation syndromes including systemic juvenile idiopathic arthritis (sJIA) and multisystem inflammatory syndrome in children (MIS-C). Cytokine storm syndrome (CSS) is an acute complication in ~2% of KD patients; however, the incidence is likely underestimated as many clinical and laboratory features of both diseases overlap. CSS should be entertained when a child with KD is unresponsive to IVIG therapy with recalcitrant fever. Early recognition and prompt institution of immunomodulatory treatment can substantially reduce the mortality and morbidity of CSS in KD. Given the known pathogenetic role of IL-1β in both syndromes, the early use of IL-1 blockers in refractory KD with CSS deserves consideration.

Efficacy of canakinumab in patients with Still's disease across different lines of biologic therapy: real-life data from the International AIDA Network Registry for Still's Disease

Introduction

The effectiveness of canakinumab may change according to the different times it is used after Still's disease onset. This study aimed to investigate whether canakinumab (CAN) shows differences in short- and long-term therapeutic outcomes, according to its use as different lines of biologic treatment.

Methods

Patients included in this study were retrospectively enrolled from the AutoInflammatory Disease Alliance (AIDA) International Registry dedicated to Still's disease. Seventy-seven (51 females and 26 males) patients with Still's disease were included in the present study. In total, 39 (50.6%) patients underwent CAN as a first-line biologic agent, and the remaining 38 (49.4%) patients were treated with CAN as a second-line biologic agent or subsequent biologic agent.

Results

No statistically significant differences were found between patients treated with CAN as a first-line biologic agent and those previously treated with other biologic agents in terms of the frequency of complete response (p =0.62), partial response (p =0.61), treatment failure (p >0.99), and frequency of patients discontinuing CAN due to lack or loss of efficacy (p =0.2). Of all the patients, 18 (23.4%) patients experienced disease relapse during canakinumab treatment, 9 patients were treated with canakinumab as a first-line biologic agent, and nine patients were treated with a second-line or subsequent biologic agent. No differences were found in the frequency of glucocorticoid use (p =0.34), daily glucocorticoid dosage (p =0.47), or concomitant methotrexate dosage (p =0.43) at the last assessment during CAN treatment.

Conclusion

Canakinumab has proved to be effective in patients with Still's disease, regardless of its line of biologic treatment.

Still's disease continuum from childhood to elderly: data from the international AIDA Network Still's disease registry

OBJECTIVE

Still's disease is more frequently observed in the paediatric context, but a delayed onset is not exceptional both in the adulthood and in the elderly. However, whether paediatric-onset, adult-onset and elderly-onset Still's disease represent expressions of the same disease continuum or different clinical entities is still a matter of controversy. The aim of this study is to search for any differences in demographic, clinical features and response to treatment between pediatric-onset, adult-onset and elderly-onset Still's disease.

METHODS

Subjects included in this study were drawn from the International AutoInflammatory Disease Alliance Network registry for patients with Still's disease.

RESULTS

A total of 411 patients suffering from Still's disease were enrolled; the disease occurred in the childhood in 65 (15.8%) patients, in the adult 314 (76.4%) patients and in the elderly in 32 (7.8%) patients. No statistically significant differences at post-hoc analysis were observed in demographic features of the disease between pediatric-onset, adult-onset and elderly-onset Still's disease. The salmon-coloured skin rash (p=0.004), arthritis (p=0.009) and abdominal pain (p=0.007) resulted significantly more frequent among paediatric patients than in adult cases, while pleuritis (p=0.015) and arthralgia (p<0.0001) were significantly more frequent among elderly-onset patients compared with paediatric-onset subjects. Regarding laboratory data, thrombocytosis was significantly more frequent among paediatric patients onset compared with adult-onset subjects (p<0.0001), while thrombocytopenia was more frequent among elderly-onset patients although statistical significance was only bordered. No substantial differences were observed in the response to treatments.

CONCLUSIONS

Despite some minor difference between groups, overall, demographic, clinical, laboratory and treatments aspects of Still's disease were similarly observed in patients at all ages. This supports that pediatric-onset, adult-onset and elderly-onset Still's disease is the same clinical condition arising in different ages.

Population-level single-cell genomics reveals conserved gene programs in systemic juvenile idiopathic arthritis

Systemic autoimmune and autoinflammatory diseases are characterized by genetic and cellular heterogeneity. While current single-cell genomics methods provide insights into known disease subtypes, these analysis methods do not readily reveal novel cell-type perturbation programs shared among distinct patient subsets. Here, we performed single-cell RNA-Seq of PBMCs of patients with systemic juvenile idiopathic arthritis (SJIA) with diverse clinical manifestations, including macrophage activation syndrome (MAS) and lung disease (LD). We introduced two new computational frameworks called UDON and SATAY-UDON, which define patient subtypes based on their underlying disrupted cellular programs as well as associated biomarkers or clinical features. Among twelve independently identified subtypes, this analysis uncovered what we believe to be a novel complement and interferon activation program identified in SJIA-LD monocytes. Extending these analyses to adult and pediatric lupus patients found new but also shared disease programs with SJIA, including interferon and complement activation. Finally, supervised comparison of these programs in a compiled single-cell pan-immune atlas of over 1,000 healthy donors found a handful of normal healthy donors with evidence of early inflammatory activation in subsets of monocytes and platelets, nominating possible biomarkers for early disease detection. Thus, integrative pan-immune single-cell analysis resolved what we believe to be new conserved gene programs underlying inflammatory disease pathogenesis and associated complications.

Molecular Pathways in the Pathogenesis of Systemic Juvenile Idiopathic Arthritis

Systemic juvenile idiopathic arthritis (sJIA) is a rare childhood chronic inflammatory disorder with risk for life-threatening complications including macrophage activation syndrome and lung disease. At onset, sJIA pathogenesis resembles that of the autoinflammatory periodic fever syndromes with marked innate immune activation, expansion of neutrophils and monocytes, and high levels of interleukin-18. Here, we review the current conceptual understanding of sJIA pathogenesis with a focus on both innate and adaptive immune pathways. Finally, we consider how recent progress toward understanding the immunologic basis of sJIA may support new therapies for refractory disease courses.

Derivation and validation of four patient clusters in Still's disease, results from GIRRCS AOSD-study group and AIDA Network Still Disease Registry

BACKGROUND

Different patient clusters were preliminarily suggested to dissect the clinical heterogeneity in Still's disease. Thus, we aimed at deriving and validating disease clusters in a multicentre, observational, prospective study to stratify these patients.

METHODS

Patients included in GIRRCS AOSD-study group and AIDA Network Still Disease Registry were assessed if variables for cluster analysis were available (age, systemic score, erythrocyte sedimentation rate (ESR), C reactive protein (CRP) and ferritin). K-means algorithm with Euclidean metric and Elbow plot were used to derive an adequate number of clusters.

RESULTS

K-means clustering assessment provided four clusters based on means standardised according to z-scores on 349 patients. All clusters mainly presented fever, skin rash and joint involvement. Cluster 1 was composed by 115 patients distinguished by lower values of age and characterised by skin rash myalgia, sore throat and splenomegaly. Cluster 2 included 128 patients identified by lower levels of ESR, ferritin and systemic score; multiorgan manifestations were less frequently observed. Cluster 3 comprised 31 patients categorised by higher levels of CRP and ferritin, they were characterised by fever and joint involvement. Cluster 4 contained 75 patients derived by higher values of age and systemic score. Myalgia, sore throat, liver involvement and life-threatening complications, leading to a high mortality rate, were observed in these patients.

CONCLUSIONS

Four patient clusters in Still's disease may be recognised by a multidimensional characterisation ('Juvenile/Transitional', 'Uncomplicated', 'Hyperferritinemic' and 'Catastrophic'). Of interest, cluster 4 was burdened by an increased rate of life-threatening complications and mortality, suggesting a more severe patient group.

The administration of methotrexate in patients with Still's disease, "real-life" findings from AIDA Network Still Disease Registry

OBJECTIVES

To describe clinical characteristics of patients with Still's disease treated with methotrexate (MTX) and to assess drug effectiveness evaluating change in disease activity, reduction of inflammatory markers, and glucocorticoid (GC)-sparing effect.

METHODS

Patients with Still's disease treated with MTX were assessed among those included in AIDA Network Still Disease Registry.

RESULTS

In this registry, 171 patients with Still's disease were treated with MTX (males 43.3%, age 37.1 ± 16.0 years). They were mainly characterised by joint features and fever without a prominent multiorgan involvement. MTX was administered with GCs in 68.4% of patients, with other conventional synthetic DMARDs in 6.4%, and with biologic DMARDs in 25.1%. A significant reduction of the modified systemic score was observed, and 38.6% patients were codified as being in clinical remission at the end of follow-up. The concomitant administration of a biologic DMARD resulted a predictor of the clinical remission. Furthermore, a reduction of inflammatory markers and ferritin levels was observed following the administration of MTX. Additionally, a marked reduction of the dosage of concomitant GCs was identified, while 36.7% discontinued such drugs. Male gender appeared as a predictor of GC discontinuation. MTX was discontinued in 12.3% of patients because of adverse effects, and in 12.3% for lack of efficacy.

CONCLUSIONS

Clinical characteristics of patients with Still's disease treated with MTX were described, mainly joint features and fever without a prominent multiorgan involvement. The clinical usefulness of MTX was reported in reducing the disease activity, decreasing the inflammatory markers, and as GC-sparing agent.

Treatment pattern and changes in oral glucocorticoid dose after tocilizumab treatment in patients with adult Still's disease: An analysis of a Japanese claims database

AIM

Intravenous tocilizumab (TCZ-IV) was approved for the treatment of adult Still's disease (ASD) in Japan in May 2019 based on its efficacy and safety in a phase III randomized controlled trial. This study determined treatment patterns in patients with ASD and assessed oral glucocorticoid (GC) dose changes after TCZ-IV administration in Japanese clinical practice.

METHODS

Patients in the Medical Data Vision database aged 16 years or older with one or more of International Classification of Diseases, 10th revision codes M061 (ASD) or M082 (systemic juvenile idiopathic arthritis) during January 2017-March 2021 (cohort 1) and those initiating TCZ-IV during May 2019-March 2021 (cohort 2) were included.

RESULTS

In cohort 1, the proportion of patients who were prescribed interleukin-6 inhibitors (mainly TCZ-IV) increased from 10.8% (January-April 2019 [before TCZ-IV approval]; n = 2002) to 18.3% (January-March 2021 [after TCZ-IV approval]; n = 2008). In cohort 2 (n = 193), 84.5% of patients were on oral GCs (≤5 mg/day: 23.8%) at index date (initial TCZ-IV prescription date); 46/70 (65.7%) were on oral GC at 5 mg/day or higher 12 months after TCZ-IV treatment (primary outcome). After 12 months of treatment, the TCZ-IV retention rate was 73.6% and the TCZ-IV administration interval was every 4 weeks and every 2 weeks in 31.9% and 27.7% of patients, respectively.

CONCLUSION

The use of interleukin-6 inhibitors increased by 7.5% points in Japanese patients with ASD ~2 years after TCZ-IV approval, suggesting that an unmet medical need existed. This study suggests the potential GC-sparing effect of TCZ-IV in patients with ASD in clinical practice.

Pyroptosis: the potential eye of the storm in adult-onset Still's disease

Pyroptosis, a form of programmed cell death with a high pro-inflammatory effect, causes cell lysis and leads to the secretion of countless interleukin-1β (IL-1β) and IL-18 cytokines, resulting in a subsequent extreme inflammatory response through the caspase-1-dependent pathway or caspase-1-independent pathway. Adult-onset Still's disease (AOSD) is a systemic inflammatory disease with extensive disease manifestations and severe complications such as macrophage activation syndrome, which is characterized by high-grade inflammation and cytokine storms regulated by IL-1β and IL-18. To date, the pathogenesis of AOSD is unclear, and the available therapy is unsatisfactory. As such, AOSD is still a challenging disease. In addition, the high inflammatory states and the increased expression of multiple pyroptosis markers in AOSD indicate that pyroptosis plays an important role in the pathogenesis of AOSD. Accordingly, this review summarizes the molecular mechanisms of pyroptosis and describes the potential role of pyroptosis in AOSD, the therapeutic practicalities of pyroptosis target drugs in AOSD, and the therapeutic blueprint of other pyroptosis target drugs.

Care pathway analysis and evidence gaps in adult-onset Still's disease: interviews with experts from the UK, France, Italy, and Germany

Introduction

Adult-onset Still's disease (AOSD) is a rare systemic inflammatory disease of unknown etiology. Published AOSD data are limited, and clinical guidelines were lacking until recently. Managing AOSD remains largely empirical with uncertainties and high variability about the optimal care pathway. Therefore, we used a qualitative approach to collect clinical judgments from the UK, Italy, France and Germany to inform the development of an agreed care pathway. Our work aimed to decrease the uncertainty associated with clinical practice, inform future research in AOSD, and help identify standardized definitions and outcomes in this population.

Methods

Semi-structured interviews and thematic analysis were conducted. Eleven clinicians were interviewed between May and July 2022: four were based in Italy, three in the UK, two in France, and two in Germany.

Results

In this work, we identified the structure of the typical care pathway for AOSD patients, which can be used to inform future economic models in AOSD. The general structure of the pathway was similar across countries. Non-steroidal anti-inflammatory drugs are prescribed during the diagnostic workup while an additive approach is commonly used in confirmed cases: corticosteroids, conventional synthetic disease-modifying antirheumatic drugs, then biologic disease-modifying antirheumatic drugs (bDMARDs) (dose increased before switching). For severe presentations, more aggressive approaches with higher doses and early use of bDMARDs are used. The main elements of variation among countries and clinicians were the criteria used for diagnosis; order of bDMARDs and preferential treatments for articular and systemic patients; and tests for patient monitoring. There is also a lack of standardized outcome measures making comparisons and evidence synthesis challenging.

Conclusion

We identified important evidence gaps for clinical practice, e.g., reliable tests or scores predictive of disease progression and treatment outcome, and recommendations for research, e.g., reporting of compliance rates and use of the Yamaguchi criteria for clinical study inclusion. Consensus is needed around the use of the Systemic score in clinical practice and the clinical utility of this score. A standardized definition of remission is also required in AOSD, and further research should look to identify and validate the specific laboratory markers to be considered when assessing remission.

A review of the pleiotropic actions of the IFN-inducible CXC chemokine receptor 3 ligands in the synovial microenvironment

Chemokines are pivotal players in instigation and perpetuation of synovitis through leukocytes egress from the blood circulation into the inflamed articulation. Multitudinous literature addressing the involvement of the dual-function interferon (IFN)-inducible chemokines CXCL9, CXCL10 and CXCL11 in diseases characterized by chronic inflammatory arthritis emphasizes the need for detangling their etiopathological relevance. Through interaction with their mutual receptor CXC chemokine receptor 3 (CXCR3), the chemokines CXCL9, CXCL10 and CXCL11 exert their hallmark function of coordinating directional trafficking of CD4+ TH1 cells, CD8+ T cells, NK cells and NKT cells towards inflammatory niches. Among other (patho)physiological processes including infection, cancer, and angiostasis, IFN-inducible CXCR3 ligands have been implicated in autoinflammatory and autoimmune diseases. This review presents a comprehensive overview of the abundant presence of IFN-induced CXCR3 ligands in bodily fluids of patients with inflammatory arthritis, the outcomes of their selective depletion in rodent models, and the attempts at developing candidate drugs targeting the CXCR3 chemokine system. We further propose that the involvement of the CXCR3 binding chemokines in synovitis and joint remodeling encompasses more than solely the directional ingress of CXCR3-expressing leukocytes. The pleotropic actions of the IFN-inducible CXCR3 ligands in the synovial niche reiteratively illustrate the extensive complexity of the CXCR3 chemokine network, which is based on the intercommunion of IFN-inducible CXCR3 ligands with distinct CXCR3 isoforms, enzymes, cytokines, and infiltrated and resident cells present in the inflamed joints.

Canakinumab as first-line biological therapy in Still's disease and differences between the systemic and the chronic-articular courses: Real-life experience from the international AIDA registry

Objective

Interleukin (IL)-1 inhibitors are largely employed in patients with Still's disease; in cases with refractory arthritis, IL-6 inhibitors have shown to be effective on articular inflammatory involvement. The aim of the present study is to assess any difference in the effectiveness of the IL-1β antagonist canakinumab prescribed as first-line biologic agent between the systemic and the chronic-articular Still's disease.

Methods

Data were drawn from the retrospective phase of the AutoInflammatory Disease Alliance (AIDA) international registry dedicated to Still's disease. Patients with Still's disease classified according to internationally accepted criteria (Yamaguchi criteria and/or Fautrel criteria) and treated with canakinumab as first-line biologic agent were enrolled.

Results

A total of 26 patients (17 females, 9 males; 18 patients developing Still's disease after the age of 16 years) were enrolled; 16 (61.5%) patients suffered from the systemic pattern of the disease; 10 (38.5%) patients suffered from the chronic-articular type. No differences were observed between the systemic and the chronic-articular Still's disease in the frequency of complete response, of flares after the start of canakinumab (p = 0.701) and in the persistence in therapy (p = 0.62). No statistical differences were observed between the two groups after 3 months, 12 months and at the last assessment in the decrease of: the systemic activity score (p = 0.06, p = 0.17, p = 0.17, respectively); the disease activity score on 28 joints (p = 0.54, p = 0.77, p = 0.98, respectively); the glucocorticoid dosage (p = 0.15, p = 0.50, and p = 0.50, respectively); the use of concomitant disease modifying anti-rheumatic drugs (p = 0.10, p = 1.00, and p = 1.00, respectively). No statistically significant differences were observed in the decrease of erythrocyte sedimentation rate (p = 0.34), C reactive protein (p = 0.48), and serum ferritin levels (p = 0.34) after the start of canakinumab.

Conclusion

Canakinumab used for Still's disease has been effective in controlling both clinical and laboratory manifestations disregarding the type of disease course when used as first-line biotechnological agent. These excellent results might have been further enhanced by the early start of IL-1 inhibition.

Refractory systemic onset juvenile idiopathic arthritis: current challenges and future perspectives

Systemic juvenile idiopathic arthritis (SJIA) is a rare disease with distinct features not seen in other categories of juvenile idiopathic arthritis. In recent years, advances in the understanding of disease immunopathogenesis have led to improved targeted therapies with significant improvement in patient outcomes. Despite these advances, there remain subsets of SJIA with refractory disease and severe disease-associated complications. This review highlights existing options for treatment of refractory SJIA and explores potential future therapeutics for refractory disease.Key Points:Despite targeted Interleukin IL-1 and IL-6 inhibitors a subset of SJIA remains refractory to therapy. About 1 in 7 SJIA patients will be refractory to targeted IL-1 or IL-6 therapy.There is no current agreed upon definition for refractory SJIA and we propose in this review that refractory SJIA is presence of active systemic or arthritic features despite treatment with anti-IL-1 or anti-IL-6 therapy or disease requiring glucocorticoids for control beyond 6 months.SJIA disease associated complications include presence of associated macrophage activation syndrome (MAS), interstitial lung disease (ILD) or amyloidosis and management of each differs.Refractory SJIA treatment options currently include additional conventional synthetic disease modifying anti-rheumatic drugs (csDMARDS), biologic (bDMARDS), combination biologic therapy, targeted synthetic (tsDMARDS) or other immunomodulatory therapies.

Rare, rarer, lung involvement in adult-onset Still's disease: A mini-review

Adult-onset Still's disease (AOSD) is a polygenic systemic autoinflammatory disease which is associated with increased morbidity and mortality. Pulmonary involvement is a rare, but serious complication of AOSD. As in AOSD, IL-1b, IL-18, and IL-6 dominate the molecular pathogenesis, which mediate a type 1 and type 3 inflammatory signature of the adaptive immune system. This is evidenced by the success of IL-1- and IL-6 inhibition in the management of AOSD. However, anaphylactic reactions to treatment with IL-1- or IL-6-inhibitors is currently being discussed as a potential trigger for lung involvement inf AOSD, while genetic risk factors have also been identified. Clinically, pulmonary involvement in AOSD can manifest in many different forms. Parenchymal inflammation with peripheral consolidations is the most frequent form while PAH is less common, but often very difficult to manage. This mini-review provides an overview of the pathophysiology as well as the clinical presentation and the diagnostic features of pulmonary involvement in AOSD.

New insights on multigenic autoinflammatory diseases

Autoinflammatory diseases are disorders of the innate immune system, which can be either monogenic due to a specific genetic mutation or complex multigenic due to the involvement of multiple genes. The aim of this review is to explore and summarize the recent advances in pathogenesis, diagnosis, and management of genetically complex autoinflammatory diseases, such as Schnitzler's syndrome; adult-onset Still's disease; synovitis, acne, pustulosis, hyperostosis, osteitis syndrome/chronic recurrent multifocal osteomyelitis/chronic non-bacterial osteomyelitis; Adamantiades-Behçet's disease; Yao syndrome; and periodic fever with aphthous stomatitis, pharyngitis, and adenitis syndrome. The PubMed database was screened for relevant articles using free text words and specific search strings. The search was limited to English-language articles, reporting the results of studies in humans, published through March 2021. Evidence from literature suggest that these rare multigenic autoinflammatory diseases can present with different clinical features and the diagnosis of these diseases can be challenging due to a combination of nonspecific manifestations that can be seen in a variety of other conditions. Diagnostic delays and disease complications may occur due to low disease awareness and the lack of pathognomonic markers. The pathogeneses of these diseases are complex and in some cases precise pathogenesis is not clearly understood. Conventional treatments are commonly used for the management of these conditions, but biologics have shown promising results. Biologics targeting proinflammatory cytokines including IL-1, IL-6, TNF-α, IL-17A and IL-18 have been shown to ameliorate signs and symptoms of different multigenic autoinflammatory diseases.

Anakinra in Patients With Systemic Juvenile Idiopathic Arthritis: Long-term Safety From the Pharmachild Registry

OBJECTIVE

To evaluate the long-term safety profile of anakinra in patients with systemic juvenile idiopathic arthritis (sJIA).

METHODS

Data from patients with sJIA enrolled in the Pharmachild registry (ClinicalTrials.gov: NCT03932344) prior to September 30, 2018, and treated with anakinra were analyzed. The study endpoints were the occurrence of non-serious adverse events (SAEs) of at least moderate severity and SAEs, including macrophage activation syndrome (MAS), and the duration of anakinra treatment with reasons for discontinuation. All endpoints were analyzed overall by 6-month time windows, and in different treatment sets represented by those patients treated continuously with anakinra for at least 12, 18, and 24 months (set-12, -18, and -24, respectively).

RESULTS

Three hundred six patients were enrolled. Of these patients, 46%, 34%, and 28% had been treated for at least 12, 18, and 24 months, respectively. Two hundred and one AEs, mostly represented by infections, were reported for 509.3 patient-years (PY) with an overall incidence rate (IR) of 39.5 per 100 PY. Among 56 SAEs (IR 11.0/100 PY), 23.2% were infections and 19.6% MAS episodes. The IR of AEs was higher during the first 6 months of anakinra treatment, followed by decreasing IRs in the long-term treatment sets. Treatment discontinuation occurred in 76% of patients, most frequently in the first 6 months, because of inefficacy (43%), remission (31%), or AEs/intolerance (15%). No deaths or malignancies occurred during anakinra treatment.

CONCLUSION

The results of the present study confirm the long-term safety profile of anakinra in patients with sJIA and demonstrate an overall decreasing incidence of AEs over time. [ClinicalTrials.gov: NCT01399281 and NCT03932344].

Progress in Biological Therapies for Adult-Onset Still’s Disease

Adult-onset Still’s disease (AOSD) is a rare multifactorial autoinflammatory disorder of unknown etiology, characterized by an excessive release of cytokines triggered by dysregulated inflammation and articular and systemic manifestations. The clinical spectrum of AOSD ranges from self-limiting forms with mild symptoms to life-threatening cases and presents clinical and biological similarities with the juvenile form (sJIA). Nowadays, the advances in biologic agents no longer limit the treatment to NSAIDs, glucocorticoids, or conventional synthetic DMARDs. The blockade of IL-1 and IL-6 is effective in the treatment of systemic and articular inflammation of AOSD patients; however, novel compounds with different properties and targets are now available and others are being studied. In this review, starting from the pathogenesis of AOSD, we summarized the current and emerging biological therapies, possible effective agents for achieving AOSD control and remission.

Severe delayed hypersensitivity reactions to IL-1 and IL-6 inhibitors link to common HLA-DRB1*15 alleles

OBJECTIVES

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe, delayed hypersensitivity reaction (DHR). We observed DRESS to inhibitors of interleukin 1 (IL-1) or IL-6 in a small group of patients with Still's disease with atypical lung disease. We sought to characterise features of patients with Still's disease with DRESS compared with drug-tolerant Still's controls. We analysed human leucocyte antigen (HLA) alleles for association to inhibitor-related DHR, including in a small Kawasaki disease (KD) cohort.

METHODS

In a case/control study, we collected a multicentre series of patients with Still's disease with features of inhibitor-related DRESS (n=66) and drug-tolerant Still's controls (n=65). We retrospectively analysed clinical data from all Still's subjects and typed 94/131 for HLA. European Still's-DRESS cases were ancestry matched to International Childhood Arthritis Genetics Consortium paediatric Still's cases (n=550) and compared for HLA allele frequencies. HLA association also was analysed using Still's-DRESS cases (n=64) compared with drug-tolerant Still's controls (n=30). KD subjects (n=19) were similarly studied.

RESULTS

Still's-DRESS features included eosinophilia (89%), AST-ALT elevation (75%) and non-evanescent rash (95%; 88% involving face). Macrophage activation syndrome during treatment was frequent in Still's-DRESS (64%) versus drug-tolerant Still's (3%; p=1.2×10-14). We found striking enrichment for HLA-DRB1*15 haplotypes in Still's-DRESS cases versus INCHARGE Still's controls (p=7.5×10-13) and versus self-identified, ancestry-matched Still's controls (p=6.3×10-10). In the KD cohort, DRB1*15:01 was present only in those with suspected anakinra reactions.

CONCLUSIONS

DRESS-type reactions occur among patients treated with IL-1/IL-6 inhibitors and strongly associate with common HLA-DRB1*15 haplotypes. Consideration of preprescription HLA typing and vigilance for serious reactions to these drugs are warranted.

Disparities in the prevalence of clinical features between systemic juvenile idiopathic arthritis and adult-onset Still's disease

OBJECTIVE

To compare clinical features and treatments of patients with systemic juvenile idiopathic arthritis (sIJA) and adult-onset Still's disease (AOSD).

METHODS

The clinical charts of consecutive patients with sJIA by International League of Association of Rheumatology criteria or AOSD by Yamaguchi criteria were reviewed. Patients were seen at a large paediatric rheumatology referral centre or at 10 adult rheumatology academic centres. Data collected included clinical manifestations, inflammation biomarkers, systemic score, macrophage activation syndrome (MAS), parenchymal lung disease, disease course, disability, death, and medications administered.

RESULTS

166 patients (median age at diagnosis 5 years) with sJIA and 194 patients with AOSD (median age at diagnosis 41 years) were included. The frequency of fever, rash, arthralgia, abdominal pain, MAS, parenchymal lung disease, and increased acute phase reactants and ferritin were comparable between the two cohorts. Patients with sJIA had a higher prevalence of arthritis, whereas patients with AOSD had experienced more frequently leucocytosis and extra-articular organ involvement. Patients with AOSD were given more commonly low-dose corticosteroids, whereas biologic DMARDs were administered first-line more frequently in patients with sJIA.

CONCLUSION

We found remarkable disparities in the prevalence of clinical manifestations between the two illnesses, which may partly depend on their classification by different criteria.

Similar Clinical Outcomes in Patients with Systemic Juvenile Idiopathic Arthritis and Adult-Onset Still's Disease Treated with Canakinumab: Bayesian and Population Model-Based Analyses

Introduction

Systemic juvenile idiopathic arthritis (sJIA) and adult-onset Still’s disease (AOSD) represent pediatric and adult variants of the Still’s disease continuum. To determine whether clinical outcomes between patients with sJIA and AOSD were similar, Bayesian and population model-based analyses were conducted on endpoints from studies of canakinumab in both patient populations. The objective was to further support the efficacy of canakinumab in patients with AOSD.

Methods

A Bayesian analysis of endpoints from a study of canakinumab in AOSD was conducted borrowing information from five pooled sJIA studies using a robust meta-analytic predictive (MAP) approach. Similarity of clinical outcomes across populations was fulfilled if the AOSD study posterior median fell within the 95% predicted credible interval for the outcome of interest, based on the pooled sJIA data. Population model-based analyses (pharmacokinetic [PK] and PK/pharmacodynamic [PKPD]) were conducted to compare the pharmacokinetics and exposure–response relationships between populations.

Results

The AOSD study posterior medians for adapted American College of Rheumatology (ACR)30 response, continuous adapted ACR response, number of active joints, C-reactive protein, and absence of fever were within the 95% credible interval for the prediction of the MAP analysis from the pooled sJIA data, supporting the similarity in outcomes between patient populations. PK analysis demonstrated comparable exposure across sJIA age groups and patients with AOSD. PKPD relationships were consistent across patient populations. Analyses indicated that no therapeutic benefit can be expected from a dose increase in patients with AOSD.

Conclusion

The analyses presented support the similarity of clinical outcomes following treatment with canakinumab in patients with sJIA and AOSD.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40744-021-00422-9.

Neutrophil Homeostasis and Emergency Granulopoiesis: The Example of Systemic Juvenile Idiopathic Arthritis

Neutrophils are key pathogen exterminators of the innate immune system endowed with oxidative and non-oxidative defense mechanisms. More recently, a more complex role for neutrophils as decision shaping cells that instruct other leukocytes to fine-tune innate and adaptive immune responses has come into view. Under homeostatic conditions, neutrophils are short-lived cells that are continuously released from the bone marrow. Their development starts with undifferentiated hematopoietic stem cells that pass through different immature subtypes to eventually become fully equipped, mature neutrophils capable of launching fast and robust immune responses. During severe (systemic) inflammation, there is an increased need for neutrophils. The hematopoietic system rapidly adapts to this increased demand by switching from steady-state blood cell production to emergency granulopoiesis. During emergency granulopoiesis, the de novo production of neutrophils by the bone marrow and at extramedullary sites is augmented, while additional mature neutrophils are rapidly released from the marginated pools. Although neutrophils are indispensable for host protection against microorganisms, excessive activation causes tissue damage in neutrophil-rich diseases. Therefore, tight regulation of neutrophil homeostasis is imperative. In this review, we discuss the kinetics of neutrophil ontogenesis in homeostatic conditions and during emergency myelopoiesis and provide an overview of the different molecular players involved in this regulation. We substantiate this review with the example of an autoinflammatory disease, i.e. systemic juvenile idiopathic arthritis.

Detection and Prediction of Macrophage Activation Syndrome in Still's Disease

Distinguishing between macrophage activation syndrome (MAS) and a simple flare of Still’s disease (SD) may be challenging. We sought to clarify the clinical features and outcome of MAS in SD and to explore predictive factors of MAS development. Demographic and clinical data, treatments, and outcomes were recorded in a cohort of 206 SD patients. SD patients with and without MAS were compared. To explore predictive factors for the development of MAS, patients were compared at the time of SD diagnosis. Twenty (9.7%) patients experienced MAS, which was inaugural in 12 cases. Patients with MAS were more likely to have hepatomegaly (OR, 3.71; 95% CI, 1.14–11.2; p = 0.03) and neurological symptoms (OR, 4.43; 95% CI, 1.08–15.3; p = 0.04) than patients without MAS. Cytopenias, abnormal liver tests, and coagulation disorders were significantly more frequent in patients with MAS; lactate dehydrogenase and serum ferritin levels were significantly higher. An optimized threshold of 3500 μg/L for serum ferritin yielded a sensitivity (Se) of 85% and a negative predictive value (NPV) of 97% for identifying patients with/without MAS. Survival analysis showed that a high ferritin level at the time of SD diagnosis was predictive of MAS development (p < 0.001). Specific factors, including neurological symptoms, cytopenias, elevated LDH, and coagulopathy, may contribute to the early detection of MAS. Extreme hyperferritinemia at the onset of SD is a prognostic factor for the development of MAS.

Update on the therapy of adult-onset Still's disease with a focus on IL-1-inhibition: a systematic review

Introduction:

The past decade has seen increasingly rapid advances in understanding the pathogenic nature of adult-onset Still’s disease (AOSD) and its shared symptoms with the systemic juvenile idiopathic arthritis (sJIA). Interleukin-1 (IL-1) blocking agents are key elements in the treatment. In this updated systematic review, we focus on studies on efficacy and safety of IL-1 blockers published in the past 5 years and review on latest available therapies.

Methods:

We conducted searches using Medline, Biosis, Embase, and Cochrane databases between 2016 and 2021 using the terms AOSD, IL1, IL-18, canakinumab, anakinra, tadekinig, and rilonacept and if applicable their trade names. Duplicates, case reports, and manuscripts with incomplete data were excluded.

Results:

Of the 1013 screened publications, 17 were eligible after careful selection. We only found two published randomized controlled studies in the past 5 years. Review manuscripts of rare diseases, like our work, usually rely on retrospective studies and case series. Anakinra and canakinumab can be successfully used as first- or further-line treatment in patients with AOSD refractory to steroids. A homogeneous outcome is not established yet. Thus, a combination of clinical and laboratory tests can support the experienced clinician in the decision-making process.

Conclusion:

The approval of IL-1 inhibitors for AOSD brought us into a new era in the treatment of AOSD. The overall efficacy-safety profile of the IL-1 inhibitors is favorable reflecting a targeted approach as standard of care. We can expect that the successful treatment of AOSD with IL-1 inhibition will facilitate further clinical and basic research with impact on other auto-inflammatory and hyper-inflammatory conditions.

Current and emerging biological therapy in adult-onset Still's disease

Adult-onset Still's disease (AOSD) is a rare, but characteristic non-familial, multi-genic systemic auto-inflammatory disorder, characterized by high spiking fever, salmon-like evanescent skin rash, polyarthritis, sore throat, hyperferritinemia and leucocytosis. The hallmark of AOSD is a cytokine storm triggered by dysregulation of inflammation. Nowadays, with advances in anti-cytokine biologic agents, the treatment of AOSD is no longer limited to NSAIDs, glucocorticoids or conventional synthetic DMARDs. In this review, we focussed on the roles of these cytokines in the pathogenesis of AOSD and summarized the current and emerging biological therapy.

Efficacy and safety of canakinumab in the treatment of adult-onset Still's disease: A systematic review

BACKGROUND

Adult-onset Still's disease (AOSD) is a rare inflammatory disease, typically characterized by spiking fever, skin rash, and arthralgia or arthritis. Its conventional treatment includes NSAIDs and corticosteroids, and DMARDs as second-line therapy. Frequently, IL-1 inhibitors are also required, mainly in patients refractory to traditional therapy. Canakinumab is a monoclonal antibody that binds IL-1β with high affinity and specificity, making it appropriate for therapeutic purposes in AOSD.

OBJECTIVE

The aim of this systematic review was to identify and compile the current data on the efficacy and safety of canakinumab in the treatment of AOSD.

METHODS

Following the guidelines established by the PRISMA statement, we searched Scopus, Web of Science, Pubmed, and Cochrane Library for relevant literature up to March 2021. The inclusion criteria comprised: randomized controlled trials, pooled analyses, observational studies, case series, and case reports.

RESULTS

Seventeen studies published from 2012 to 2021 were evaluated; 11 of these correspond to case series or case reports, four observational studies, one placebo-controlled phase II trial, and one analysis of pooled systemic juvenile idiopathic arthritis data. In general, out of a total of 99 patients, 68.7% of these presented a complete remission of the systemic and arthritic manifestations at the end of the observation period, while 16.2% of the patients showed a partial improvement of the symptoms and the remaining (15.1%) did not show clinical improvement or were excluded. Moreover, 210 adverse events were reported in 69 patients during canakinumab treatment, of which the majority correspond to respiratory tract infections, arthralgia, disease flares, abdominal pain, nausea, and diarrhea, whereas the most common severe adverse events included macrophage activation syndrome and serious infections. Also, a corticosteroid-sparing effect was observed in a large percentage of patients.

CONCLUSION

More studies with solid evidence are needed to support the efficacy of canakinumab in AOSD, although its use is encouraged by the increasing favorable results reported and the efficacy of other IL-1 inhibitors. It was also associated with an acceptable safety profile, similar to expected in IL-1 inhibitor therapy. However, future studies with well-defined endpoints are warranted to examine further the usefulness of canakinumab in AOSD.

Acute liver failure in Still's disease relapse during pregnancy: case report and discussion of a possible trigger role of DILI

BACKGROUND

Still's disease is a rare systemic inflammatory disease with frequent but generally mild liver involvement. The most common cause of acute liver failure in western countries is drug-induced liver injury, while it has rarely been reported in subjects suffering from Still's disease.

CASE PRESENTATION

We report a case of a young woman presenting with SD reactivation in pregnancy and acute liver failure after delivery with a possible triggering role of drug induced liver injury.

CONCLUSIONS

The prompt recognition of Still's disease reactivation allowed early introduction of steroid therapy and resolution of the clinical picture. We discuss potential factors precipitating ALF in this case, and implications for the diagnosis and management of such patients.

Autoinflammation and autoimmunity across rheumatic and musculoskeletal diseases

Most rheumatic and musculoskeletal diseases (RMDs) can be placed along a spectrum of disorders, with autoinflammatory diseases (including monogenic systemic autoinflammatory diseases) and autoimmune diseases (such as systemic lupus erythematosus and antiphospholipid syndrome) representing the two ends of this spectrum. However, although most autoinflammatory diseases are characterized by the activation of innate immunity and inflammasomes and classical autoimmunity typically involves adaptive immune responses, there is some overlap in the features of autoimmunity and autoinflammation in RMDs. Indeed, some 'mixed-pattern' diseases such as spondyloarthritis and some forms of rheumatoid arthritis can also be delineated. A better understanding of the pathogenic pathways of autoinflammation and autoimmunity in RMDs, as well as the preferential cytokine patterns observed in these diseases, could help us to design targeted treatment strategies.

Application of systems biology-based in silico tools to optimize treatment strategy identification in Still's disease

Background

Systemic juvenile idiopathic arthritis (sJIA) and adult-onset Still’s disease (AOSD) are manifestations of an autoinflammatory disorder with complex pathophysiology and significant morbidity, together also termed Still’s disease. The objective of the current study is to set in silico models based on systems biology and investigate the optimal treat-to-target strategy for Still’s disease as a proof-of-concept of the modeling approach.

Methods

Molecular characteristics of Still’s disease and data on biological inhibitors of interleukin (IL)-1 (anakinra, canakinumab), IL-6 (tocilizumab, sarilumab), and glucocorticoids as well as conventional disease-modifying anti-rheumatic drugs (DMARDs, methotrexate) were used to construct in silico mechanisms of action (MoA) models by means of Therapeutic Performance Mapping System (TPMS) technology. TPMS combines artificial neuronal networks, sampling-based methods, and artificial intelligence. Model outcomes were validated with published expression data from sJIA patients.

Results

Biologicals demonstrated more pathophysiology-directed efficiency than non-biological drugs. IL-1 blockade mainly acts on proteins implicated in the innate immune system, while IL-6 signaling blockade has a weaker effect on innate immunity and rather affects adaptive immune mechanisms. The MoA models showed that in the autoinflammatory/systemic phases of Still’s disease, in which the innate immunity plays a pivotal role, the IL-1β-neutralizing antibody canakinumab is more efficient than the IL-6 receptor-inhibiting antibody tocilizumab. MoA models reproduced 67% of the information obtained from expression data.

Conclusions

Systems biology-based modeling supported the preferred use of biologics as an immunomodulatory treatment strategy for Still’s disease. Our results reinforce the role for IL-1 blockade on innate immunity regulation, which is critical in systemic autoinflammatory diseases. This further encourages early use on Still’s disease IL-1 blockade to prevent the development of disease or drug-related complications. Further analysis at the clinical level will validate the findings and help determining the timeframe of the window of opportunity for canakinumab treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02507-w.

Adult-Onset Still's Disease: Clinical Aspects and Therapeutic Approach

Adult-onset Still's disease (AoSD) is a rare systemic autoinflammatory disease characterized by arthritis, spiking fever, skin rash and elevated ferritin levels. The reason behind the nomenclature of this condition is that AoSD shares certain symptoms with Still's disease in children, currently named systemic-onset juvenile idiopathic arthritis. Immune dysregulation plays a central role in AoSD and is characterized by pathogenic involvement of both arms of the immune system. Furthermore, the past two decades have seen a large body of immunological research on cytokines, which has attributed to both a better understanding of AoSD and revolutionary advances in treatment. Additionally, recent studies have introduced a new approach by grouping patients with AoSD into only two phenotypes: one with predominantly systemic features and one with a chronic articular disease course. Diagnosis presupposes an extensive diagnostic workup to rule out infections and malignancies. The severe end of the spectrum of this disease is secondary haemophagocytic lymphohistiocytosis, better known as macrophage activation syndrome. In this review, we discuss current research conducted on the pathogenesis, diagnosis, classification, biomarkers and complications of AoSD, as well as the treatment strategy at each stage of the disease course. We also highlight the similarities and differences between AoSD and systemic-onset juvenile idiopathic arthritis. There is a considerable need for large multicentric prospective trials.

Development and initial validation of a composite disease activity score for systemic juvenile idiopathic arthritis

OBJECTIVE

To develop a composite disease activity score for systemic JIA (sJIA) and to provide preliminary evidence of its validity.

METHODS

The systemic Juvenile Arthritis Disease Activity Score (sJADAS) was constructed by adding to the four items of the original JADAS a fifth item that aimed to quantify the activity of systemic features. Validation analyses were conducted on patients with definite or probable/possible sJIA enrolled at first visit or at the time of a flare, who had active systemic manifestations, which should include fever. Patients were reassessed 2 weeks to 3 months after baseline. Three versions were examined, including ESR, CRP or no acute-phase reactant.

RESULTS

A total of 163 patients were included at 30 centres in 10 countries. The sJADAS was found to be feasible and to possess face and content validity, good construct validity, satisfactory internal consistency (Cronbach's alpha 0.64-0.65), fair ability to discriminate between patients with different disease activity states and between those whose parents were satisfied or not satisfied with illness outcome (P < 0.0001 for both), and strong responsiveness to change over time (standardized response mean 2.04-2.58). Overall, these properties were found to be better than those of the original JADAS and of DAS for RA and of Puchot score for adult-onset Still's disease.

CONCLUSION

The sJADAS showed good measurement properties and is therefore a valid instrument for the assessment of disease activity in children with sJIA. The performance of the new tool should be further examined in other patient cohorts that are evaluated prospectively.

Interleukin-1 Blockade in Polygenic Autoinflammatory Disorders: Where Are We now?

Polygenic autoinflammatory diseases (AIDs), such as systemic juvenile idiopathic arthritis (sJIA), adult-onset Still's disease, Kawasaki disease, idiopathic recurrent pericarditis (IRP), Behçet’s Syndrome, Crystal-induced arthropatihes such as gout or Calcium pyrophosphate deposition disease are characterized by the overexpression of inflammasome-associated genes, leading to a dysregulation of the innate immune response. The IL-1 cytokine family (IL-1α, IL-1β, IL-1Ra, IL-18, IL-36Ra, IL-36α, IL-37, IL-36β, IL-36g, IL-38, IL-33) was defined to be principally responsible for the inflammatory nature of polygenic AIDs. Several clinical trials were initiated, and IL-1 blockade has been proven to cause a rapid reduction of clinical symptoms and normalization of laboratory parameters in the majority of cases. Randomized, placebo-controlled, clinical trials, together with registry-based clinical trials and open-label, retrospective and prospective observational studies, supported the efficacy and safety of IL-1 inhibitors in the treatment of polygenic AIDs. Most of the current data are focused on the therapeutic use of anakinra, an IL-1 receptor antagonist, canakinumab, an anti-IL-1β monoclonal antibody, and rilonacept, a soluble decoy receptor. However, other promising agents, such as gevokizumab, IL-1β blocking monoclonal antibody, tadekinig alfa, a human recombinant IL-18-binding protein, and tranilast, an analog of a tryptophan metabolite, are currently being tested. Anakinra, canakinumab and rilonacept caused impressive improvements in both systemic and musculoskeletal symptoms. Furthermore, the anti-IL-1 therapy allowed corticosteroid tapering and, in some cases, even withdrawal. This article reviews the current IL-1 inhibitors and the results of all clinical trials in which they have been tested for the management of broad spectrum of polygenic AIDs.

Outcome of refractory to conventional and/or biologic treatment adult Still's disease following canakinumab treatment: Countrywide data in 50 patients

OBJECTIVE

To assess the efficacy and safety of the IL-1b inhibitor canakinumab in all adults with refractory Still's disease identified from the National Organization For Medicines for off-label drug use.

METHODS

In a retrospective longitudinal multicenter cohort of 50 patients (median age 39 years) with active Still's disease despite treatment with corticosteroids (n = 11), conventional and synthetic (n = 34) and/or biologic disease modifying anti-rheumatic drugs (n = 30), we assessed the efficacy of canakinumab 150-300 mg administered every 4 (n = 47) or 8 weeks (n = 3) as combination therapy or monotherapy (n = 7) during a median follow-up of 27 (3-84) months.

RESULTS

Α complete response was initially observed in 78% of patients within 3 months (median), irrespective of age at disease onset. A partial response was evident in 20%. One patient had resistant disease. Treatment de-escalation was attempted in 15 of 39 complete responders and a complete drug discontinuation in 21 patients for 8 months (median). Eleven patients (22%) relapsed during treatment, one during de-escalation process, and 11 after treatment discontinuation. Overall, 9 of 11 relapses were successfully treated with canakinumab treatment intensification or re-introduction. At last visit, 18% of patients were off treatment due to remission and 26% due to disease activity. Canakinumab had a significant corticosteroid sparing effect allowing weaning in 21 of 41 cases. Infections (20%, severe 4%) and leucopenia (6%) led to treatment cessation in one patient.

CONCLUSION

High rates of sustained remission were observed in this, largest so far, real-life cohort of adult patients with refractory Still's disease treated with canakinumab.

[Still's disease as biphasic disorder : Current knowledge on pathogenesis and novel treatment approaches]

Still's disease covers a range of disorders from systemic juvenile idiopathic arthritis (SJIA) up to adult onset Still's disease (AOSD). The overlapping clinical features suggest that SJIA and AOSD are different manifestations of a phenotypic continuum in different age stages. Still's disease is clinically characterized by fever, rash, joint involvement, lymphadenopathy and serositis. In this review the more recent pathogenetic model of a biphasic disease course is presented. The initial autoinflammation with predominant dysregulation of innate immunity is the basis of the "window of opportunity" hypothesis for the early use of a cytokine blockade. If the disease is not stopped in this phase, a phenotype change to a disease with destructive arthritis regularly occurs, in which dysregulation of the mechanisms of adaptive immunity plays a special role. The understanding of Still's disease as a biphasic disease enables the monitoring of molecular signatures. At the same time, this opens up perspectives for phase-specific targeted treatment using modern treat-to-target strategies.

Analisi di budget impact di anakinra nel trattamento della Malattia di Still in Italia

Background:

Anakinra, canakinumab and tocilizumab are all effective alternative treatment choice in patients with Still’s disease including both systemic juvenile idiopathic arthritis (SJIA) and adult onset Still’s disease (AOSD).

Objective:

Aim of this study was to estimate the budget impact of the use of anakinra compared to canakinumab and tocilizumab in the treatment of patients with AOSD or SJIA.

Methods:

Considering the perspective of the Italian National Health Service (iNHS), a budget impact model (BIM) was developed to estimate the drug costs of anakinra, canakinumab and tocilizumab up to 12 months. The BIM showed the difference of drug expenditure generated by the base case calculated for current prescription volumes, and for different prescription volume scenarios with increased anakinra prescription. Key variables were tested in the sensitivity analysis.

Results:

Compared to the current scenario for SJIA, an increase in the market share of anakinra (40% or 50%) would lead to a reduction in the drug expenditure sustained by iNHS (–€1,087,494 [–12.4%] or –€2,023,990 [–23.1%]). Compared to the current scenario for AOSD, an increase in the market share of anakinra (40% or 50%) would lead to a reduction in the drug expenditure sustained by iNHS (–€4,024,585 [–13.5%] or –€8,049,169 [–27.0%]).

Conclusion:

According to the present analysis, the use of anakinra, as an alternative to canakinumab or tocilizumab in patients with AOSD or SJIA, could represent a cost-saving option for the iNHS.

Canakinumab for Treatment of Adult-Onset Still's Disease to Achieve Reduction of Arthritic Manifestation (CONSIDER): phase II, randomised, double-blind, placebo-controlled, multicentre, investigator-initiated trial

BACKGROUND

Inhibition of interleukin (IL)-1 represents a promising treatment option in adult-onset Still's disease (AOSD).

OBJECTIVE

To investigate the efficacy and safety of canakinumab in patients with AOSD and active joint involvement by means of a multicentre, double-blind, randomised, placebo-controlled trial.

METHODS

Patients with AOSD and active joint involvement (tender and swollen joint counts of ≥4 each) were treated with canakinumab (4 mg/kg, maximum 300 mg subcutaneous every 4 weeks) or placebo. The primary endpoint was the proportion of patients with a clinically relevant reduction in disease activity at week 12 as determined by the change in disease activity score (ΔDAS28>1.2).

RESULTS

At enrolment, patients had high active disease with a mean DAS28(ESR) of 5.4 in the canakinumab and 5.3 in the placebo group, respectively. In the intention-to-treat analysis, 12 patients (67%) in the canakinumab group and 7 patients (41%) in the placebo group fulfilled the primary outcome criterion (p=0.18). In the per-protocol analysis, significantly higher American College of Rheumatology (ACR) 30% (61% vs 20%, p=0.033), ACR 50% (50% vs 6.7%, p=0.009) and ACR 70% (28% vs 0%, p=0.049) response rates were observed in the canakinumab group compared with the placebo group. Two patients in the canakinumab group experienced a serious adverse event.

CONCLUSION

Although the study was terminated prematurely and the primary endpoint was not achieved, treatment with canakinumab led to an improvement of several outcome measures in AOSD. The overall safety findings were consistent with the known profile of canakinumab. Thus, our data support indication for IL-1 inhibition with canakinumab in AOSD.