Canakinumab reduces the risk of acute gouty arthritis flares during initiation of allopurinol treatment: results of a double-blind, randomised study

Mechanism of macrophages in gout: Recent progress and perspective

Gout represents an autoinflammatory disorder instigated by monosodium urate crystals. Its primary manifestation involves the recruitment of diverse immune cell populations, including neutrophils and macrophages. Macrophages assume a pivotal role in the initiation of acute gouty inflammation and subsequent inflammatory cascades. However, recent investigations have revealed that the impact of macrophages on gout is nuanced, extending beyond a solely detrimental influence. Macrophages, characterized by different subtypes, exhibit distinct functionalities that either contribute to the progression or regression of gout. A strategy aimed at modulating macrophage polarization, rather than merely inhibiting inflammation, holds promise for enhancing the efficacy of acute gout treatment. This review centres on elucidating potential mechanisms underlying macrophage polarization in the onset and resolution of gouty inflammation, offering novel insights into the immune equilibrium of macrophages in the context of gout.

Controversies and practical management of patients with gout and chronic kidney disease

Uric acid is a toxin retained with advancing kidney disease. Clinical manifestations of hyperuricemia include gout and systemic inflammation that are associated with increased risk of cardiovascular mortality. As many as one-third of all patients with chronic kidney disease have a history of gout, yet <25% of these patients are effectively treated to target serum urate levels of ≤6 mg/dl. A major reason for ineffective management of gout and hyperuricemia is the complexity in managing these patients, with some medications contraindicated and others requiring special dosing, potential drug interactions, and other factors. Consequently, many nephrologists do not primarily manage gout despite it being a common complication of chronic kidney disease, leaving management to the primary physician or rheumatologist. We believe that kidney specialists should consider gout as a major complication of chronic kidney disease and actively manage it in their patients. Here, we present insights from nephrologists and rheumatologists for a team approach to gout management that includes the nephrologist.

Newer Therapies in Rheumatology

Seven of the 11 newer medications recently or soon to be approved to treat rheumatologic diseases discussed in this article are biologic agents and reflect the current ability of science to target specific components of the immune system. The other agents are molecules that are directed against specific immune pathway targets as well. All have shown superiority to placebo and in some cases have been compared to currently accepted therapies. Safety issues are generally centered around infections due to the immune-interrupting nature of these therapies.

Mastoparan M Suppressed NLRP3 Inflammasome Activation by Inhibiting MAPK/NF-κB and Oxidative Stress in Gouty Arthritis

Background

Gouty arthritis is characterized by the accumulation of monosodium urate crystals (MSU) in the synovial joints and surrounding tissues. Mastoparan M (Mast-M) is a biologically active peptide composed of 14 amino acids, extracted from wasp venom. This study aims to assess the impact of Mast-M on in vitro and in vivo gouty arthritis induced by lipolyaccharide (LPS) plus MSU crystal stimulation.

Methods

PMA-differentiated THP-1 macrophages were pre-treated with Mast-M or left untreated, followed by stimulation with LPS and MSU crystals. Cell lysates were collected to assess the expression of the NLRP3 inflammasome, inflammatory signaling pathways, and oxidative stress. Furthermore, to evaluate the in vivo anti-inflammatory effect of Mast-M, an experimental acute gouty arthritis mouse model was established through intra-articular injection of MSU crystals.

Results

Mast-M treatment demonstrated significant inhibition of the phosphorylation of MAPKs/NF-κB signaling pathways and reduction in oxidative stress expression in LPS and MSU-induced THP-1 macrophages. This resulted in the suppression of downstream NLRP3 inflammasome activation and IL-1β release. In vivo, Mast-M effectively attenuated the inflammation induced by MSU in mice with gouty arthritis. Specifically, Mast-M reduced swelling in the paws, inhibited the infiltration of neutrophils and macrophages into periarticular tissue, and decreased the activation of the NLRP3 inflammasome and IL-1β production.

Conclusion

Mast-M significantly improves gouty arthritis, and its potential mechanism may be achieved by inhibiting the MAPK/NF-κB pathway and alleviating oxidative stress, thus suppressing the activation of NLRP3 inflammasomes.

Mechanisms and rationale for uricase use in patients with gout

Xanthine oxidase inhibitors such as allopurinol and febuxostat have been the mainstay urate-lowering therapy (ULT) for treating hyperuricaemia in patients with gout. However, not all patients receiving oral ULT achieve the target serum urate level, in part because some patients cannot tolerate, or have actual or misconceived contraindications to, their use, mainly due to comorbidities. ULT dosage is also limited by formularies and clinical inertia. This failure to sufficiently lower serum urate levels can lead to difficult-to-treat or uncontrolled gout, usually due to poorly managed and/or under-treated gout. In species other than humans, uricase (urate oxidase) converts urate to allantoin, which is more soluble in urine than uric acid. Exogenic uricases are an exciting therapeutic option for patients with gout. They can be viewed as enzyme replacement therapy. Uricases are being used to treat uncontrolled gout, and can achieve rapid reduction of hyperuricaemia, dramatic resolution of tophi, decreased chronic joint pain and improved quality of life. Availability, cost and uricase immunogenicity have limited their use. Uricases could become a leading choice in severe and difficult-to-treat gout as induction and/or debulking therapy (that is, for lowering of the urate pool) to be followed by chronic oral ULT. This Review summarizes the evidence regarding available uricases and those in the pipeline, their debulking effect and their outcomes related to gout and beyond.

NLR family pyrin domain containing 3 (NLRP3) inflammasomes and peripheral neuropathic pain - Emphasis on microRNAs (miRNAs) as important regulators

Neuropathic pain is caused by the lesion or disease of the somatosensory system and can be initiated and/or maintained by both central and peripheral mechanisms. Nerve injury leads to neuronal damage and apoptosis associated with the release of an array of pathogen- or damage-associated molecular patterns to activate inflammasomes. The activation of the NLR family pyrin domain containing 3 (NLRP3) inflammasome contributes to neuropathic pain and may represent a novel target for pain therapeutic development. In the current review, we provide an up-to-date summary of the recent findings on the involvement of NLRP3 inflammasome in modulating neuropathic pain development and maintenance, focusing on peripheral neuropathic conditions. Here we provide a detailed review of the mechanisms whereby NLRP3 inflammasomes contribute to neuropathic pain via (1) neuroinflammation, (2) apoptosis, (3) pyroptosis, (4) proinflammatory cytokine release, (5) mitochondrial dysfunction, and (6) oxidative stress. We then present the current research literature reporting on the antinociceptive effects of several natural products and pharmacological interventions that target activation, expression, and/or regulation of NLRP3 inflammasome. Furthermore, we emphasize the effects of microRNAs as another regulator of NLRP3 inflammasome. In conclusion, we summarize the possible caveats and future perspectives that might provide successful therapeutic approaches against NLRP3 inflammasome for treating or preventing neuropathic pain conditions.

Korean guidelines for the management of gout

Gout is the most common form of arthritis, with the prevalence increasing worldwide. The present treatment guidelines provide recommendations for the appropriate treatment of acute gout, management during the inter-critical period, and prevention of chronic complications. The guidelines were developed based on evidence-based medicine and draft recommendations finalized after expert consensus. These guidelines are designed to provide clinicians with clinical evidence to enable efficient treatment of gout.

Interleukin-1β inhibitors for the management of acute gout flares: a systematic literature review

OBJECTIVES

The objective of this systematic review was to assess the effects of interleukin-1β (IL-1β) inhibitors on gout flares.

METHODS

Studies published between 2011 and 2022 that evaluated the effects of IL-1β inhibitors in adult patients experiencing gout flares were eligible for inclusion. Outcomes including pain, frequency and intensity of gout flares, inflammation, and safety were assessed. Five electronic databases (Pubmed/Medline, Embase, Biosis/Ovid, Web of Science and Cochrane Library) were searched. Two independent reviewers performed study screening, data extraction and risk of bias assessments (Cochrane Risk of Bias Tool 2 for randomised controlled trials [RCTs] and Downs and Black for non-RCTs). Data are reported as a narrative synthesis.

RESULTS

Fourteen studies (10 RCTs) met the inclusion criteria, with canakinumab, anakinra, and rilonacept being the three included IL-1β inhibitors. A total of 4367 patients with a history of gout were included from the 14 studies (N = 3446, RCTs; N = 159, retrospective studies [with a history of gout]; N = 762, post hoc analysis [with a history of gout]). In the RCTs, canakinumab and rilonacept were reported to have a better response compared to an active comparator for resolving pain, while anakinra appeared to be not inferior to an active comparator for resolving pain. Furthermore, canakinumab and rilonacept reduced the frequency of gout flares compared to the comparators. All three medications were mostly well-tolerated compared to their comparators.

CONCLUSION

IL-1β inhibitors may be a beneficial and safe medication for patients experiencing gout flares for whom current standard therapies are unsuitable.

REVIEW PROTOCOL REGISTRATION

PROSPERO ID: CRD42021267670.

Korean guidelines for the management of gout

Gout is the most common form of arthritis, with the prevalence increasing worldwide. The present treatment guidelines provide recommendations for the appropriate treatment of acute gout, management during the inter-critical period, and prevention of chronic complications. The guidelines were developed based on evidence-based medicine and draft recommendations finalized after expert consensus. These guidelines are designed to provide clinicians with clinical evidence to enable efficient treatment of gout.

Development of a novel anti-inflammatory recombinant uricase with extended half-life for gout therapy

Gout is a form of inflammatory arthritis that results from elevated serum uric acid levels and the deposition of urate crystals in multiple joints. The inflammatory response during an acute gout attack is mediated by the activation of the NLRP3 inflammasome, leading to the release of IL-1β and inducing a localized tissue inflammatory response. Urate lowering therapies such as Pegloticase effectively reduce serum uric acid levels but are generally associated with an increase in acute gout flares. In this study, we developed a long-acting anti-inflammatory recombinant uricase by sequential fusing interleukin-1 receptor antagonist (IL-1Ra) and albumin-binding domain (ABD) with the N-terminal end of Arthrobacter globiformis uricase (AgUox). The recombinant uricase has longer in vivo half-life, and significantly alleviates monosodium urate (MSU) crystals induced inflammation in mouse model compared with the wild-type AgUox. This long-acting anti-inflammatory recombinant uricase has the potential to be developed as an effective urate lowering therapy with better safety profiles.

The Hong Kong Society of Rheumatology consensus recommendations for the management of gout

Gout is one of the most common noncommunicable diseases in Hong Kong. Although effective treatment options are readily available, the management of gout in Hong Kong remains suboptimal. Like other countries, the treatment goal in Hong Kong usually focuses on relieving symptoms of gout but not treating the serum urate level to target. As a result, patients with gout continue to suffer from the debilitating arthritis, as well as the renal, metabolic, and cardiovascular complications associated with gout. The Hong Kong Society of Rheumatology spearheaded the development of these consensus recommendations through a Delphi exercise that involved rheumatologists, primary care physicians, and other specialists in Hong Kong. Recommendations on acute gout management, gout prophylaxis, treatment of hyperuricemia and its precautions, co-administration of non-gout medications with urate-lowering therapy, and lifestyle advice have been included. This paper serves as a reference guide to all healthcare providers who see patients who are at risk and are known to have this chronic but treatable condition.

When underlying biology threatens the randomization principle - initial gout flares of urate-lowering therapy

Flare is the dominant feature of gout and occurs because of inflammatory response to monosodium urate crystals; prevention of gout flares should be the major goal of gout care. However, a paradoxical increase in the risk of flare following initiation of urate-lowering therapy presents considerable challenges for proving the expected long-term benefits of flare prevention in clinical trials. Nevertheless, excluding from enumeration flares that occur in the initial post-randomization period (which can last several months to 1 year) can threaten the core benefits of randomization: the characteristics of the remaining participants can differ from those who were randomized, introducing potential bias from confounding (both measured and unmeasured); participants who drop out or die are excluded from the analysis, introducing potential selection bias; and, finally, ignoring initial flares underestimates participants' experience during the trial. This Perspective discusses these issues and recommends measures that will allow for high-level evidence that preserves the randomization principle, to satisfy methodological scrutiny and generate robust evidence-based guidelines for gout care.

Systematic Review of Safety and Efficacy of IL-1-Targeted Biologics in Treating Immune-Mediated Disorders

Background

The cytokine interleukin (IL)-1 plays a pivotal role in immune-mediated disorders, particularly in autoinflammatory diseases. Targeting this cytokine proved to be efficacious in treating numerous IL-1-mediated pathologies. Currently, three IL-1 blockers are approved, namely anakinra, canakinumab and rilonacept, and two additional ones are expected to receive approval, namely gevokizumab and bermekimab. However, there is no systematic review on the safety and efficacy of these biologics in treating immune-mediated diseases.

Objective

To evaluate safety and efficacy of anakinra, canakinumab, rilonacept, gevokizumab, and bermekimab for the treatment of immune-mediated disorders compared to placebo, standard-of-care treatment or other biologics.

Methods

The PRISMA checklist guided the reporting of the data. We searched the PubMed database between 1 January 1984 and 31 December 2020 focusing on immune-mediated disorders. Our PubMed literature search identified 7363 articles. After screening titles and abstracts for the inclusion and exclusion criteria and assessing full texts, 75 articles were included in a narrative synthesis.

Results

Anakinra was both efficacious and safe in treating cryopyrin-associated periodic syndromes (CAPS), familial Mediterranean fever (FMF), gout, macrophage activation syndrome, recurrent pericarditis, rheumatoid arthritis (RA), and systemic juvenile idiopathic arthritis (sJIA). Conversely, anakinra failed to show efficacy in graft-versus-host disease, Sjögren’s syndrome, and type 1 diabetes mellitus (T1DM). Canakinumab showed efficacy in treating CAPS, FMF, gout, hyper-IgD syndrome, RA, Schnitzler’s syndrome, sJIA, and TNF receptor-associated periodic syndrome. However, use of canakinumab in the treatment of adult-onset Still’s disease and T1DM revealed negative results. Rilonacept was efficacious and safe for the treatment of CAPS, FMF, recurrent pericarditis, and sJIA. Contrarily, Rilonacept did not reach superiority compared to placebo in the treatment of T1DM. Gevokizumab showed mixed results in treating Behçet’s disease-associated uveitis and no benefit when assessed in T1DM. Bermekimab achieved promising results in the treatment of hidradenitis suppurativa.

Conclusions

This systematic review of IL-1-targeting biologics summarizes the current state of research, safety, and clinical efficacy of anakinra, bermekimab, canakinumab, gevokizumab, and rilonacept in treating immune-mediated disorders.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42021228547.

The Mechanism of the NLRP3 Inflammasome Activation and Pathogenic Implication in the Pathogenesis of Gout

The NACHT, LRR, and PYD-domains-containing protein 3 (NLRP3) inflammasome is an intracellular multi-protein signaling platform that is activated by cytosolic pattern-recognition receptors such as NLRs against endogenous and exogenous pathogens. Once it is activated by a variety of danger signals, recruitment and assembly of NLRP3, ASC, and pro-caspase-1 trigger the processing and release of pro-inflammatory cytokines including interleukin-1β (IL-1β) and IL-18. Multiple intracellular and extracellular structures and molecular mechanisms are involved in NLRP3 inflammasome activation. Gout is an autoinflammatory disease induced by inflammatory response through production of NLRP3 inflammasome-mediated proinflammatory cytokines such as IL-1β by deposition of monosodium urate (MSU) crystals in the articular joints and periarticular structures. NLRP3 inflammasome is considered a main therapeutic target in MSU crystal-induced inflammation in gout. Novel therapeutic strategies have been proposed to control acute flares of gouty arthritis and prophylaxis for gout flares through modulation of the NLRP3/IL-1 axis pathway. This review discusses the basic mechanism of NLRP3 inflammasome activation and the IL-1-induced inflammatory cascade and explains the NLRP3 inflammasome-induced pathogenic role in the pathogenesis of gout.

The Interaction Between Dietary Fructose and Gut Microbiota in Hyperuricemia and Gout

With the worldwide epidemics of hyperuricemia and associated gout, the diseases with purine metabolic disorders have become a serious threat to human public health. Accumulating evidence has shown that they have been linked to increased consumption of fructose in humans, we hereby made a timely review on the roles of fructose intake and the gut microbiota in regulating purine metabolism, together with the potential mechanisms by which excessive fructose intake contributes to hyperuricemia and gout. To this end, we focus on the understanding of the interaction between a fructose-rich diet and the gut microbiota in hyperuricemia and gout to seek for safe, cheap, and side-effect-free clinical interventions. Furthermore, fructose intake recommendations for hyperuricemia and gout patients, as well as the variety of probiotics and prebiotics with uric acid-lowering effects targeting the intestinal tract are also summarized to provide reference and guidance for the further research.

Systems model identifies baseline cytokine concentrations as potential predictors of rheumatoid arthritis inflammatory response to biologics

BACKGROUND AND PURPOSE

Circulating cytokines are central pathological mediators of inflammatory autoimmune diseases like rheumatoid arthritis (RA). Immunological diversity in patients might contribute to inadequate responses to biological drugs. To address this therapeutic challenge, we developed a mathematical model that simultaneously describes temporal patterns of drug disposition for several biologics and their corresponding targeted cytokines, which were linked to triggering inflammatory responses.

EXPERIMENTAL APPROACH

A modeling framework was applied to RA-relevant cytokines regulating C-reactive protein (CRP) as an inflammatory marker. Clinical data were extracted from the literature for anakinra, canakinumab, infliximab, secukinumab, and tocilizumab, along with their corresponding cytokines: interleukin-1 receptor antagonist, IL-1β, tumor necrosis factor α (TNFα), IL-17A, and IL-6 receptor (IL-6R). Based on prior knowledge of regulatory mechanisms, cytokines were integrated with CRP profiles.

KEY RESULTS

The model well captured all serum concentration-time profiles of cytokines and CRP ratios to respective baselines following drug treatment with good precision. On external validation, reasonable model-performance on CRP dynamics, including rebound effects, was confirmed with clinical data not used in model development. Model-based simulations demonstrated that serum infliximab concentrations were accurately recapitulated in both a dose- and baseline TNFα-dependent manner. Furthermore, high baseline profiles of both IL-1β and/or targeted cytokines could be predictors of poor responses to biologics targeting TNFα and IL-6R, although the impact of IL-1β must be carefully interpreted.

CONCLUSIONS AND IMPLICATION

Our model provides a quantitative platform to guide targeting and dosing strategies, including combination and/or sequential therapy, according to distinct baseline cytokine patterns in RA patients.

Guizhi-Shaoyao-Zhimu decoction attenuates monosodium urate crystal-induced inflammation through inactivation of NF-κB and NLRP3 inflammasome

ETHNOPHARMACOLOGICAL RELEVANCE

Guizhi-Shaoyao-Zhimu decoction (GSZD), a classical traditional Chinese medicine (TCM) prescription, is used empirically to treat various types of arthritis in TCM clinical practice. However, the underlying mechanisms of GSZD on gouty inflammation are not totally elucidated.

AIM OF STUDY

The purpose of this study is to investigate the effects of GSZD on peritoneal recruitment of neutrophils, production of proinflammatory mediators, activations of nuclear factor (NF)-κB and nucleotide oligomerization domain-like receptor protein-3 (NLRP3) inflammasome in mice with monosodium urate crystal (MSU)-induced peritonitis (MIP).

MATERIALS AND METHODS

Mice were intragastrically administered with GSZD for 7 days. After the last administration, mice were intraperitoneally injected with MSU. Peritoneal exudates of mice were harvested, and total peritoneal cells were calculated. Levels of interleukin (IL)-1β, IL-6 and monocyte chemotactic protein (MCP)-1 in peritoneal exudates were tested by enzyme-linked immunosorbent assay. Expressions of IL-1β, NLRP3, cysteinyl aspartate specific proteinase (caspase)-1, apoptosis-associated speck-like protein containing the caspase activation and recruitment domain (ASC), phosphorylated (p)-p65, inhibitor of NF-κB (IκB)α, p-IκB kinase (IKK)β, nuclear p65, p-mitogen-activated protein kinases (MAPKs) in peritoneal cells were analyzed by Western blot. Binding activity of NF-κB to DNA was measured by a Trans AM™ kit for p65. Interaction between ASC and pro-caspase-1 was assessed by co-immunoprecipitation assay.

RESULTS

Total peritoneal cells, levels of IL-1β, IL-6 and MCP-1 were significantly reduced by GSZD treatment in peritoneal exudates of MIP mice. As for the activation of NF-κB, GSZD treatment significantly reduced the levels of p-p65, p-IKKβ, nuclear p65 and p-MAPKs, enhanced the level of IκBα and abated the binding ability of NF-κB to DNA in peritoneal cells of MIP mice. As for the activation of NLRP3 inflammasome, GSZD treatment significantly reduced the levels of IL-1β, NLRP3 and caspase-1, and alleviated the interaction between ASC and pro-caspase-1 in peritoneal cells of MIP mice. Nevertheless, GSZD didn't remarkably change the level of ASC.

CONCLUSIONS

These results suggest that GSZD attenuates the MSU-induced inflammation through inhibiting the activations of NF-κB and NLRP3 inflammasome.

Colchicine for acute gout

BACKGROUND

This is an updated Cochrane Review, first published in 2006 and updated in 2014. Gout is one of the most common rheumatic diseases worldwide. Despite the use of colchicine as one of the first-line therapies for the treatment of acute gout, evidence for its benefits and harms is relatively limited.

OBJECTIVES

To update the available evidence of the benefits and harms of colchicine for the treatment of acute gout.

SEARCH METHODS

We updated the search of CENTRAL, MEDLINE, Embase, Clinicaltrials.gov and WHO ICTRP registries to 28 August 2020. We did not impose any date or language restrictions in the search.

SELECTION CRITERIA

We considered published randomised controlled trials (RCTs) and quasi-randomised controlled trials (quasi-RCTs) evaluating colchicine therapy compared with another therapy (placebo or active) in acute gout; low-dose colchicine at clinically relevant doses compared with placebo was the primary comparison. The major outcomes were pain, participant global assessment of treatment success (proportion with 50% or greater decrease in pain from baseline up to 32 to 36 hours), reduction of inflammation, function of target joint, serious adverse events, total adverse events and withdrawals due to adverse events.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as expected by Cochrane in this review update.

MAIN RESULTS

We included four trials (803 randomised participants), including two new trials, in this updated review. One three-arm trial compared high-dose colchicine (52 participants), low-dose colchicine (74 participants) and placebo (59 participants); one trial compared high-dose colchicine with placebo (43 participants); one trial compared low-dose colchicine with non-steroidal anti-inflammatory drugs (NSAIDs) (399 participants); and one trial compared low-dose colchicine with Chuanhu anti-gout mixture (traditional Chinese Medicine compound) (176 participants). We did not identify any trials comparing colchicine to glucocorticoids (by any route). The mean age of participants ranged from 51.2 to 70 years, and trial duration from 48 hours to 12 weeks. Two trials were at low risk of bias, one was possibly susceptible to selection bias (random sequence generation), reporting bias and other bias, and one open-label trial was at high risk of performance and detection bias. For the primary comparison, low-quality evidence from one trial (103 participants, downgraded for imprecision and bias) suggests low-dose colchicine may improve treatment outcome compared to placebo with little or no increased risk of adverse events. The number of people who reported treatment success (50% or greater pain reduction) at 32 to 36 hours was slightly larger with low-dose colchicine (418 per 1000) compared with placebo (172 per 1000; risk ratio (RR) 2.43, 95% confidence interval (CI) 1.05 to 5.64; absolute improvement 25% more reported success (7% more to 42% more, the 95% CIs include both a clinically important and unimportant benefit); relative change of 143% more people reported treatment success (5% more to 464% more). The incidence of total adverse events was 364 per 1000 with low-dose colchicine compared with 276 per 1000 with placebo: RR 1.32, 95% CI 0.68 to 2.56; absolute difference 9% more events with low-dose colchicine (9% fewer to 43% more, the 95% CIs include both a clinically important effect and no effect); relative change of 32% more events (32% fewer to 156% more). No participants withdrew due to adverse events or reported any serious adverse events. Pain, inflammation and function were not reported. Low-quality evidence (downgraded for imprecision and bias) from two trials (124 participants) suggests that high-dose colchicine compared to placebo may improve symptoms, but with increased risk of harms. More participants reported treatment success at 32 to 36 hours with high-dose colchicine (518 per 1000) compared with placebo (240 per 1000): RR 2.16, 95% CI 1.28 to 3.65, absolute improvement 28% (8% more to 46% more); more also had reduced inflammation at this time point with high-dose colchicine (504 per 1000) compared with placebo (48 per 1000): RR 10.50, 95% CI 1.48 to 74.38; absolute improvement 45% greater (22% greater to 68% greater); but more adverse events were reported with high-dose colchicine (829 per 1000 compared with 260 per 1000): RR 3.21, 95% CI 2.01 to 5.11, absolute difference 57% (26% more to 74% more). Pain and function were not reported. Low-quality evidence from a single trial comparing high-dose to low-dose colchicine indicates there may be little or no difference in benefit in terms of treatment success at 32 to 36 hours but more adverse events associated with the higher dose. Similarly, low-quality evidence from a single trial indicates there may also be little or no benefit of low-dose colchicine over NSAIDs in terms of treatment success and pain reduction at seven days, with a similar number of adverse events reported at four weeks follow-up. Reduction of inflammation, function of target joint and withdrawals due to adverse events were not reported in either of these trials, and pain was not reported in the high-dose versus low-dose colchicine trial. We were unable to estimate the risk of serious adverse events for most comparisons as there were few events reported in the trials. One trial (399 participants) reported three serious adverse (one in a participant receiving low-dose colchicine and two in participants receiving NSAIDs), due to reasons unrelated to the trial (low-quality evidence downgraded for bias and imprecision).

AUTHORS' CONCLUSIONS

We found low-quality evidence that low-dose colchicine may be an effective treatment for acute gout when compared to placebo and low-quality evidence that its benefits may be similar to NSAIDs. We downgraded the evidence for bias and imprecision. While both high- and low-dose colchicine improve pain when compared to placebo, low-quality evidence suggests that high-dose (but not low-dose) colchicine may increase the number of adverse events compared to placebo, while low-quality evidence indicates that the number of adverse events may be similar with low-dose colchicine and NSAIDs. Further trials comparing colchicine to placebo or other treatment will likely have an important impact on our confidence in the effect estimates and may change the conclusions of this review. There are no trials reporting the effect of colchicine in populations with comorbidities or in comparison with other commonly used treatments, such as glucocorticoids.

Changing paradigms in the management of gout

The incidence and prevalence of gout have increased, as have comorbid obesity, diabetes mellitus, hypertension, chronic kidney and cardiovascular disease. Gout is now the commonest type of inflammatory arthritis despite availability of safe, effective and potentially 'curative' urate-lowering drugs. Modern imaging studies show that gout is a chronic inflammatory crystal deposition disorder even at the first acute attack and they illuminate the need to eliminate urate crystals by continuing reduction of the serum urate below its solubility threshold. Clinical outcomes, adherence to therapy and quality of gout care in primary care and hospital practice can be greatly improved by better use of allopurinol and flare prophylaxis, greater patient engagement, education and follow-up, and by nurse-led models of care that employ a 'treat-to-target' principle (SUA< 360 or 300µmol/l). Advances in understanding the physiology and genetic control of urate transport in the kidney and gut have led to novel, more selective uricosuric drugs, and basic research on mediators of urate crystal-induced inflammation has pointed to alternative therapeutic targets for treating and preventing gout flares. Current guidelines for the management of gout and indications for the use of some more recently introduced drugs; febuxostat, lesinurad, pegloticase and interleukin-1 antagonists are also briefly reviewed.

Features and Outcomes of Microcrystalline Arthritis Treated by Biologics: A Retrospective Study

OBJECTIVES

The usual treatments for crystal-associated arthritis are sometimes contraindicated; thus, new therapies against interleukin-1beta (IL-1) have been developed. We evaluated the characteristics of patients who received biological treatment for crystal-associated arthritis.

PATIENTS AND METHODS

We conducted a multicentric retrospective observational study in six rheumatology units in western France. Patients receiving a biological treatment for crystal-associated arthritis between 1 January 2010 and 31 December 2018 were included. Improvement was defined as at least a 50% decrease in the count of synovitis and C-reactive protein level.

RESULTS

Forty-six patients were included: 31 (67.4%) were treated for gouty arthritis, and 15 (32.6%) for calcium pyrophosphate crystal deposition disease (CCPD). The first biotherapy used was anakinra for 14 patients (93.3%) with CCPD and 31 patients (100.0%) with gout. The first biotherapy course was more efficient in treating gout than in treating CCPD, with success in 28 patients (90.3%) and 5 patients (35.7%), respectively (p = 0.001). Six patients (42.9%) with CCPD stopped their first biotherapy course because of side effects. Among the patients with gout, urate-lowering therapy was more frequently used after (100%) than before the first biotherapy course (67.7%) (p = 0.002).

CONCLUSION

Anakinra was prescribed for cases of refractory crystal-associated arthritis or cases with contraindications for usual treatments. The efficacy of anakinra in treating CCPD was not obvious. Patients with CCPD had more side effects. The biotherapy was introduced with a long-term objective, while anti-IL-1 therapies are approved for acute crises only.

A Randomized, Phase II Study Evaluating the Efficacy and Safety of Anakinra in the Treatment of Gout Flares

OBJECTIVE

To evaluate the efficacy and safety of anakinra compared to triamcinolone in the treatment of gout flares.

METHODS

Patients for whom nonsteroidal antiinflammatory drugs and colchicine were not suitable treatments were enrolled in this multicenter, randomized, double-blind study with follow-up for up to 2 years. The study was designed to assess superiority of anakinra (100 or 200 mg/day for 5 days) over triamcinolone (40 mg in a single injection) for the primary end point of changed patient-assessed pain intensity in the most affected joint (scored on a visual analog scale of 0-100) from baseline to 24-72 hours. Secondary outcome measures included: safety, immunogenicity, and patient- and physician-assessed global response.

RESULTS

One hundred sixty-five patients were randomized to receive anakinra (n = 110) or triamcinolone (n = 55). The median age was 55 years (range 25-83), 87% were men, the mean disease duration was 8.7 years, and the mean number of self-reported flares during the prior year was 4.5. A total of 301 flares were treated (214 with anakinra; 87 with triamcinolone). Anakinra in both doses and triamcinolone provided clinically meaningful reduction in patient-assessed pain intensity in the first and subsequent flares. For the first flare, the mean decline in pain intensity from baseline to 24-72 hours for total anakinra and triamcinolone was -41.2 and -39.4, respectively (P = 0.688). Anakinra performed better than triamcinolone for most secondary end points. There were no unexpected safety findings. The presence of antidrug antibodies was not associated with adverse events or altered pain reduction.

CONCLUSION

Anakinra was not superior to triamcinolone for the primary end point, but had comparable efficacy in pain reduction and was favored for most secondary end points. Anakinra is an effective option for gout flares when conventional therapy is unsuitable.

Gout and AA-Amyloidosis: A Case-Based Review

Background:

AA-amyloidosis complicates many chronic infections and inflammatory diseases, including rheumatoid arthritis, ankylosing spondylitis, and psoriatic arthritis, but its relationship to gout is extremely rare. As it is unknown definitely what the pathophysiological connections between gout and amyloidosis are, treatment issues of the diseases are open for discussion.

Aim:

To establish a link between gout and AA-amyloidosis, and to improve the quality of treatment in patients suffering from gout and AA-amyloidosis.

Methods:

We reviewed the English-language literature sources, searching not only for rare cases of the combination of gout and AA amyloidosis, but also detailed descriptions of the medical treatments for the two pathologies.

Results:

By July 2020, we had identified 14 cases describing AA amyloidosis in patients with gout. Most of those patients had been suffering tophaceous gout for at least 10 years, and were prescribed various methods of treatment; however, not all patients took colchicine regularly. In some cases, therapy with allopurinol and colchicine was effective against attacks of gouty arthritis, although amyloidogenic inflammation was not controlled sufficiently. However, there were no cases that described in detail the successful treatment of both diseases. Besides those 14 patients described in literature, we examined one more patient with amyloidosis that is secondary to gout, in whom the protein of amyloid A (AA) had affected the kidneys, intestines, and adrenal glands. The patient has been successfully treated with the combination of canakinumab, prednisone, colchicine and allopurinol.

Conclusion:

Clinicians should be aware that patients may have atypical combinations of diseases like gout and amyloidosis. The obtained results help to explain some pathogenic processes associated with AA-amyloidosis. Further research is necessary to confirm the effectiveness of different treatment options such as lifestyle biologic agents or other medicines with anti-inflammatory properties.

A systematic review of the infectious complications of colchicine and the use of colchicine to treat infections

OBJECTIVE

Colchicine has been used historically as an anti-inflammatory agent for a wide range of diseases. Little is known regarding the relationship between colchicine use and infectious disease outcomes. The objective of this study was to systematically examine infectious adverse events associated with colchicine usage and the clinical use of colchicine for infectious diseases.

METHODS

A systematic review was conducted in accordance with PRISMA methodology. PubMed, EMBASE, Scopus and Cochrane Library databases were searched (up to 12th October, 2020) for interventional and observational studies that included colchicine usage associated with infectious adverse events or infectious disease outcomes.

RESULTS

A total of 9,237 studies were initially identified and after exclusions, 36 articles comprising 21 interventional studies and 15 observational studies were included in this systematic review. There were 19 studies that reported infectious adverse events and 17 studies that examined the efficacy of colchicine in treating infectious disease. Only two out of six studies reported a significant benefit using colchicine in the management of viral liver disease. There was some evidence colchicine is beneficial in managing COVID-19 by reducing time to deterioration, length of stay in hospital and mortality. Colchicine had some benefit in managing malaria, condyloma accuminata and verruca vulgaris, viral myocarditis and erythema nodosum leprosum based on case-series or small, pilot clinical studies. Two of the clinical trials and five of the observational studies reported significant associations between infections adverse events and colchicine usage. Risk of pneumonia was found in three studies and post-operative infections were reported in two studies. Risks of urinary tract infections, H. pylori and C.difficile were only reported by one study each.

CONCLUSION

There is a current lack of clinical evidence that colchicine has a role in treating or managing infectious diseases. Preliminary studies have demonstrated a possible role in the management of COVID-19 but results from more clinical trials are needed. There is inconclusive evidence that suggests colchicine is associated with increased risk of infections, particularly pneumonia.

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.

[Results of the systematic literature search as basis for the "Evidence-based treatment recommendations for familial Mediterranean fever patients with insufficient response or intolerability to colchicine" of the Society for Pediatric and Adolescent Rheumatology and the German Society for Rheumatology]

BACKGROUND

Familial Mediterranean fever (FMF) is a genetic disease of childhood and adulthood which is relatively rare in Germany. It is characterized by recurrent febrile attacks, peritonitis, pleuritis and arthritis. The established treatment with colchicine is effective and well-tolerated by most patients; however, some patients do not adequately respond or do not tolerate this treatment. Biologics can be considered for some of these patients. The Society for Pediatric and Adolescent Rheumatology (GKJR) and the German Society for Rheumatology (DGRh) have agreed to develop joint recommendations for this specific clinical situation.

AIM

Implementation of a systematic literature search (SLR) on the basis of the EULAR recommendations published in 2016 as the foundation for the development of evidence-based treatment recommendations for FMF patients with insufficient response or intolerance to colchicine.

METHODS

The SLR was performed using references from various databases as an update of the SLR carried out by EULAR up to 2014, whereby all articles must have been published between 1 January 2015 and 31 December 2017. The Rayyan abstract tool for the preselection and the classification of the Oxford Centre for Evidence Based Medicine 2009 were used for the preparation of the evidence tables.

RESULTS

The search yielded 360 hits and after duplicate matching 263. A total of 88 publications were included (34%) and 102 excluded (39%), a review of the full publication was necessary for a further 73 (28%) and 43 were discussed more intensively. Finally, 64 publications (24%) remained. A total of 4 case-control studies, 31 cohort studies, 8 case series, 7 controlled studies (including 5 abstracts), 10 reviews, 4 meta-analyses and systematic reviews were accepted.

DISCUSSION

The SLR was carried out in a scientifically accurate and transparent manner according to international standards. The SLR proved to be a good basis for a consensus on the 5 overarching principles and the 10 recommendations, so that the joint activity of the GKJR and DGRh was successfully and even promptly concluded. The recommendations are a solid basis for treating patients of all ages with FMF. The explanations on the problem of colchicine resistance play an important role here.

Pharmacologic Management of Gout in Patients with Cardiovascular Disease and Heart Failure

Gout is the most common inflammatory arthritis and is often comorbid with cardiovascular disease (CVD). Hyperuricemia and gout are also independent risk factors for cardiovascular events, worsening heart failure (HF), and death. The recommended treatment modalities for gout have important implications for patients with CVD because of varying degrees of cardiovascular and HF benefit and risk. Therefore, it is critical to both manage hyperuricemia with urate-lowering therapy (ULT) and treat acute gout flares while minimizing the risk of adverse cardiovascular events. In this review, the evidence for the safety of pharmacologic treatment of acute and chronic gout in patients with CVD and/or HF is reviewed. In patients with CVD or HF who present with an acute gout flare, colchicine is considered safe and potentially reduces the risk of myocardial infarction. If patients cannot tolerate colchicine, short durations of low-dose glucocorticoids are efficacious and may be safe. Nonsteroidal anti-inflammatory drugs should be avoided in patients with CVD or HF. The use of canakinumab and anakinra for acute gout flares is limited by the high cost, risk of serious infection, and relatively modest clinical benefit. For long-term ULT, allopurinol, and alternatively probenecid, should be considered first-line treatments in patients with CVD or HF given their safety and potential for reducing cardiovascular outcomes. An increased risk of cardiovascular death and HF hospitalization limit the use of febuxostat and pegloticase as ULT in this population. Ultimately, the selection of agents used for acute gout management and long-term ULT should be individualized according to patient and agent cardiovascular risk factors.

Effect of canakinumab on clinical and biochemical parameters in acute gouty arthritis: a meta-analysis

BACKGROUND

Targeted anti-IL-1β therapy may be a valuable option for the management of gouty arthritis. The present meta-analysis has evaluated the effect of canakinumab, an anti-IL-1β monoclonal antibody in gouty arthritis.

METHODS

A standard meta-analysis protocol was developed and after performing a comprehensive literature search in MEDLINE, Cochrane, and International Clinical Trial Registry Platform (ICTRP), reviewers assessed eligibility and extracted data from three relevant articles. A random-effects model was used to estimate the pooled effect size as the mean difference in Visual Analouge Scale (VAS) score, serum hsCRP, serum Amyloid A, and risk ratio for global assessment between the groups. Quality assessment was done using the risk of bias assessment tool and summary of findings was prepared using standard Cochrane methodology with GradePro GDT.

RESULTS

Treatment with canakinumab showed a mean reduction of VAS score by 14.59 mm [95% CI - 19.42 to - 9.77], serum hsCRP by 15.36 mg/L [95% CI 1.62-29.11], serum Amyloid A by 67.18 mg/L [95% CI 17.06-117.31], and improvement in patient global assessment (RR = 1.478; 95% CI 1.29-1.67) and physician global assessment (RR = 1.44; 95% CI 1.28-1.61). The probability that future studies may have a mean difference in VAS score less than zero has been calculated to be 27.3% using a cumulative distribution function (CDF) calculator.

CONCLUSION

This meta-analysis shows the beneficial effect of canakinumab over triamcinolone by reducing VAS score, serum hsCRP, serum amyloid A, and improvement in global assessments in acute gouty arthritis.

NLRP3 Inflammasome in Inflammation and Metabolism: Identifying Novel Roles in Postburn Adipose Dysfunction

Inflammasomes are multiprotein complexes that respond to pathogen or host associated damage markers, leading to caspase-1 maturation and processing of pro-inflammatory cytokines. Initially, inflammasomes were implicated primarily in inflammatory and infectious conditions. However, increasing evidence demonstrates broader roles beyond inflammation, including regulation of adipose tissue metabolism after burns. Here, we conducted a search for articles on PubMed, Web of Science, Embase, Scopus, and UpToDate with applied search strategies including a combination of "burns," "trauma," "(NLRP3) inflammasome," "metabolic conditions," "white adipose tissue," "macrophages," "browning," and "lipolysis" and included papers from 2000 to 2020. We discuss unexpected roles for NLRP3, the most characterized inflammasome to date, as a key metabolic driver in a variety of conditions. In particular, we highlight the function of NLRP3 inflammasome in burn trauma, which is characterized by both hyperinflammation and hypermetabolism. We identify a critical part for NLRP3 activation in macrophage dynamics and delineate a novel role in postburn white adipose tissue remodeling, a pathological response associated with hypermetabolism and poor clinical outcomes. Mechanistically, how inflammation and inflammasome activation is linked to postburn hypermetabolism is a novel concept to contemplate, and herein we provide evidence of an immunometabolic crosstalk between adipocytes and infiltrating macrophages.

The NLRP3 Inflammasome: Role and Therapeutic Potential in Pain Treatment

Pain is a fundamental feature of inflammation. The immune system plays a critical role in the activation of sensory neurons and there is increasing evidence of neuro-inflammatory mechanisms contributing to painful pathologies. The inflammasomes are signaling multiprotein complexes that are key components of the innate immune system. They are intimately involved in inflammatory responses and their activation leads to production of inflammatory cytokines that in turn can affect sensory neuron function. Accordingly, the contribution of inflammasome activation to pain signaling has attracted considerable attention in recent years. NLRP3 is the best characterized inflammasome and there is emerging evidence of its role in a variety of inflammatory pain conditions. In vitro and in vivo studies have reported the activation and upregulation of NLRP3 in painful conditions including gout and rheumatoid arthritis, while inhibition of NLRP3 function or expression can mediate analgesia. In this review, we discuss painful conditions in which NLRP3 inflammasome signaling has been pathophysiologically implicated, as well as NLRP3 inflammasome-mediated mechanisms and signaling pathways that may lead to the activation of sensory neurons.

2020 American College of Rheumatology Guideline for the Management of Gout

OBJECTIVE

To provide guidance for the management of gout, including indications for and optimal use of urate-lowering therapy (ULT), treatment of gout flares, and lifestyle and other medication recommendations.

METHODS

Fifty-seven population, intervention, comparator, and outcomes questions were developed, followed by a systematic literature review, including network meta-analyses with ratings of the available evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, and patient input. A group consensus process was used to compose the final recommendations and grade their strength as strong or conditional.

RESULTS

Forty-two recommendations (including 16 strong recommendations) were generated. Strong recommendations included initiation of ULT for all patients with tophaceous gout, radiographic damage due to gout, or frequent gout flares; allopurinol as the preferred first-line ULT, including for those with moderate-to-severe chronic kidney disease (CKD; stage >3); using a low starting dose of allopurinol (≤100 mg/day, and lower in CKD) or febuxostat (<40 mg/day); and a treat-to-target management strategy with ULT dose titration guided by serial serum urate (SU) measurements, with an SU target of <6 mg/dl. When initiating ULT, concomitant antiinflammatory prophylaxis therapy for a duration of at least 3-6 months was strongly recommended. For management of gout flares, colchicine, nonsteroidal antiinflammatory drugs, or glucocorticoids (oral, intraarticular, or intramuscular) were strongly recommended.

CONCLUSION

Using GRADE methodology and informed by a consensus process based on evidence from the current literature and patient preferences, this guideline provides direction for clinicians and patients making decisions on the management of gout.

2020 recommendations from the French Society of Rheumatology for the management of gout: Urate-lowering therapy

OBJECTIVE

To develop French Society of Rheumatology-endorsed recommendations for the management of urate-lowering therapy (ULT).

METHODS

Evidence-based recommendations were developed by 9 rheumatologists (academic or community-based), 3 general practitioners, 1 cardiologist, 1 nephrologist and 1 patient, using a systematic literature search, one physical meeting to draft recommendations and two Delphi rounds to finalize them.

RESULTS

A set of 3 overarching principles and 5 recommendations was elaborated. The overarching principles emphasize the importance of patient education, especially the need for explaining the objective of lowering serum urate (SU) level to obtain crystal dissolution, clinical symptoms disappearance and avoidance of complications. ULT is indicated as soon as the diagnosis of gout is established. SU level must be decreased below 300μmol/l (50mg/l) in all gout patients or at least below 360μmol/l (60ml/l) when the 300μmol/l target cannot be reached, and must be maintained at these targets and monitored life-long. The choice of the ULT primarily relies on renal function: in patients whose estimated glomerular filtration rate (eGFR) is above 60ml/min/1.73m², first-line ULT is allopurinol; in those with eGFR between 30 and 60ml/min/1.73m², allopurinol use must be cautious and febuxostat can be considered as an alternative; and in those whose eGFR is below 30ml/min/1.73m², allopurinol must be avoided and febuxostat should be preferred. Prophylaxis of ULT-induced gout flares involves progressive increase of ULT dosage and low-dose colchicine for at least 6 months. Cardiovascular risk factors and diseases, the metabolic syndrome and chronic kidney disease must be screened and managed.

CONCLUSION

These recommendations aim to provide simple and clear guidance for the management of ULT in France.

2020 American College of Rheumatology Guideline for the Management of Gout

OBJECTIVE

To provide guidance for the management of gout, including indications for and optimal use of urate-lowering therapy (ULT), treatment of gout flares, and lifestyle and other medication recommendations.

METHODS

Fifty-seven population, intervention, comparator, and outcomes questions were developed, followed by a systematic literature review, including network meta-analyses with ratings of the available evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, and patient input. A group consensus process was used to compose the final recommendations and grade their strength as strong or conditional.

RESULTS

Forty-two recommendations (including 16 strong recommendations) were generated. Strong recommendations included initiation of ULT for all patients with tophaceous gout, radiographic damage due to gout, or frequent gout flares; allopurinol as the preferred first-line ULT, including for those with moderate-to-severe chronic kidney disease (CKD; stage >3); using a low starting dose of allopurinol (≤100 mg/day, and lower in CKD) or febuxostat (<40 mg/day); and a treat-to-target management strategy with ULT dose titration guided by serial serum urate (SU) measurements, with an SU target of <6 mg/dl. When initiating ULT, concomitant antiinflammatory prophylaxis therapy for a duration of at least 3-6 months was strongly recommended. For management of gout flares, colchicine, nonsteroidal antiinflammatory drugs, or glucocorticoids (oral, intraarticular, or intramuscular) were strongly recommended.

CONCLUSION

Using GRADE methodology and informed by a consensus process based on evidence from the current literature and patient preferences, this guideline provides direction for clinicians and patients making decisions on the management of gout.

Adverse events during oral colchicine use: a systematic review and meta-analysis of randomised controlled trials

Background

Colchicine is a widely used drug to treat inflammatory diseases. Due to its long historical use in medicine, controlled clinical trials have been small and there remains some caution with the use of this drug in patients with co-morbidities. The aim of the study is to systematically examine the side effect profile of colchicine in controlled clinical trials across all published indications.

Methods

A systematic review was conducted in accordance with PRISMA methodology. The Cochrane Library, MEDLINE and EMBASE were searched for double-blind controlled trials of oral colchicine in adult patients that reported adverse event data. Meta-analyses were used to determine the relative risk (RR) of adverse events in colchicine users compared to comparator groups.

Results

A total of 4915 studies were initially identified and after exclusions, 35 randomised controlled trials with placebo (n = 35) or active comparators (n = 5) were included. The most common diseases studied were gout, liver cirrhosis and pericarditis. There were a total of 8659 pooled participants, 4225 participants were randomised to receive colchicine, 3956 to placebo and 411 to an active comparator. Diarrhoea was reported in 17.9% of colchicine users versus 13.1% in comparator groups (RR 2.4, 95% confidence interval (CI) 1.6, 3.7). Any gastrointestinal event was reported in 17.6% of colchicine users and 13.1% of comparators (RR 1.7, 95% CI 1.3, 2.3). Adverse liver events were reported in 1.9% of colchicine users versus 1.1% in the comparator groups (RR 1.6, 95% CI 0.9, 3.0). Muscle events were reported in 4.2% of colchicine users and 3.3% in the comparator groups (RR 1.3, 95% CI 0.8, 1.9). Haematology events were reported in 0.6% of colchicine users and 0.4% of comparator groups (RR 1.34 (0.64, 2.82). No study reported neuropathy events. Other sensory events were reported in 1.1% of colchicine users and 1.5% of comparator groups (RR 1.4, 95% CI 0.3, 6.7). Infectious events were reported in 0.4% of colchicine users and 2.1% of comparator groups (RR 1.0, 95% CI 0.7, 1.5). No study reported death as an adverse event.

Conclusion

Colchicine increases the rate of diarrhoea and gastrointestinal adverse events but does not increase the rate of liver, sensory, muscle, infectious or haematology adverse events or death.

Gout: state of the art after a decade of developments

This review article summarizes the relevant English literature on gout from 2010 through April 2017. It emphasizes that the current epidemiology of gout indicates a rising prevalence worldwide, not only in Western countries but also in Southeast Asia, in close relationship with the obesity and metabolic syndrome epidemics. New pathogenic mechanisms of chronic hyperuricaemia focus on the gut (microbiota, ABCG2 expression) after the kidney. Cardiovascular and renal comorbidities are the key points to consider in terms of management. New imaging tools are available, including US with key features and dual-energy CT rendering it able to reveal deposits of urate crystals. These deposits are now included in new diagnostic and classification criteria. Overall, half of the patients with gout are readily treated with allopurinol, the recommended xanthine oxidase inhibitor (XOI), with prophylaxis for flares with low-dose daily colchicine. The main management issues are related to patient adherence, because gout patients have the lowest rate of medication possession ratio at 1 year, but they also include clinical inertia by physicians, meaning XOI dosage is not titrated according to regular serum uric acid level measurements for targeting serum uric acid levels for uncomplicated (6.0 mg/dl) and complicated gout, or the British Society for Rheumatology recommended target (5.0 mg/dl). Difficult-to-treat gout encompasses polyarticular flares, and mostly patients with comorbidities, renal or heart failure, leading to contraindications or side effects of standard-of-care drugs (colchicine, NSAIDs, oral steroids) for flares; and tophaceous and/or destructive arthropathies, leading to switching between XOIs (febuxostat) or to combining XOI and uricosurics.

Interleukin-1 blockade treatment decreasing cardiovascular risk

BACKGROUND

Interleukin-1 (IL-1) played a role in the occurrence and development of atherosclerosis and cardiovascular events. However, the association between IL-1 blockage treatment and reducing of cardiovascular risk remains poorly defined.

HYPOTHESIS

IL-1 blockage treatment reduce the risk and incidence rate of overall major adverse cardiovascular events (MACE), all-cause death, acute myocardial infarction(MI), unstable angina and heart failure.

METHODS

We performed a search of published reports by using MEDLINE database (January 1, 2005 to April 1, 2018). The randomized controlled trials (RCTs) that reported sample size and occurrence numbers in test group and placebo group for the associations of interest were included.

RESULTS

Eight RCT studies involving 15 647 participants were identified. Compared with those who took no IL-1 blockage, patients taking IL-1 blockage experienced a decreased risk of overall MACE (RR 0.88, 95% CI 0.82-0.94), unstable angina (RR 0.80, 95% CI 0.66-0.98), and breakthrough or recurrence of heart failure (RR 0.44, 95% CI 0.22-0.87). No association was found between IL-1 blockage treatment and death from all cause (RR 0.91, 95% CI 0.83-1.00) as well as acute MI (RR 0.85, 95% CI 0.71-1.01). The RRs associated with overall MACE, death from all cause, acute MI, and unstable angina for anakinra were 1.05, 1.16, 2.97, and 0.56, respectively, and for canakinumab were 1.05, 0.91, 0.80, and 0.80, respectively.

CONCLUSIONS

Administration of IL-1 blockage was associated with decrease risks of overall MACE, unstable angina, and breakthrough or recurrence of heart failure, but not with death from all cause as well as acute MI.

Gout

Gout is a chronic disease caused by monosodium urate (MSU) crystal deposition. Gout typically presents as an acute, self-limiting inflammatory monoarthritis that affects the joints of the lower limb. Elevated serum urate level (hyperuricaemia) is the major risk factor for MSU crystal deposition and development of gout. Although traditionally considered a disorder of purine metabolism, altered urate transport, both in the gut and the kidneys, has a key role in the pathogenesis of hyperuricaemia. Anti-inflammatory agents, such corticosteroids, NSAIDs and colchicine, are widely used for the treatment of gout flare; recognition of the importance of NLRP3 inflammasome activation and bioactive IL-1β release in initiation of the gout flare has led to the development of anti-IL-1β biological therapy for gout flares. Sustained reduction in serum urate levels using urate-lowering therapy is vital in the long-term management of gout, which aims to dissolve MSU crystals, suppress gout flares and resolve tophi. Allopurinol is the first-line urate-lowering therapy and should be started at a low dose, with gradual dose escalation. Low-dose anti-inflammatory therapies can reduce gout flares during initiation of urate-lowering therapy. Models of care, such as nurse-led strategies that focus on patient engagement and education, substantially improve clinical outcomes and now represent best practice for gout management.

[Immunology of systemic inflammatory diseases]

BACKGROUND

Inflammatory rheumatic diseases are generally systemic diseases resulting from immune system dysfunction.

METHODS

Relevant pathophysiological processes in the immune system are discussed using laboratory results and autoantibody tests, as well as in terms of new drugs in particular. Furthermore, an immunologically focused overview of clinically relevant approaches is presented.

RESULTS

The pathophysiological role of both T and B lymphocytes as well as that of autoantibodies demonstrates that diseases such as rheumatoid arthritis (RA), connective tissue diseases, and vasculitides are autoimmune diseases. While tumor necrosis factor is apparently involved in many entities, other cytokines differentiate between RA (interleukin-6, IL-6) and spondylarthritides (IL-17, IL-23). In contrast, in crystal arthritides, IL-1 appears essential.

The challenges of gout flare reporting: mapping flares during a randomized controlled trial

Background

Methods of gout flare reporting in research settings are inconsistent and poorly defined. The aim of this study was to describe patterns of gout flare and assess the concurrent validity of different methods of flare reporting in a gout clinical trial.

Methods

Daily flare diary entries including self-report of flare and pain scale from a randomised controlled trial of 120 patients with gout were analysed. Detailed pain-by-time plots for each participant were inspected and analysed for different methods of flare reporting for both self-report and the classification tree (CART)-defined flare developed by Gaffo in 2012. Concurrent validity for different methods of flare reporting were analysed.

Results

Although the single gout flare had a 'typical' average pattern (peak on day 1 and resolution over 14 days), individual pain-by-time plots showed wide variation in pain intensity, duration and frequency of flares. Over the four-month study period, there were 84/120 (70%) participants who experienced at least one self-reported flare that was not a 'typical' flare. The time to first self-reported flare correlated poorly with other measures of gout activity and other methods of flare reporting. The number of days with flare (either self-reported or Gaffo-defined) and the area under the pain-by-time curve correlated most strongly with other measures of disease severity.

Conclusion

There is wide variation in the patterns of flare over time in individuals with gout, leading to challenges for flare reporting in clinical trials. Time-dependent reporting strategies such as number of days with flare or area under the pain-by-time curve correlate well with other measures of gout disease severity and may provide a more accurate measure of flare burden.

Trial registration

Clinical trial number: ACTRN12609000479202, registered 17/06/2009.

Comparison of an interactive voice response system and smartphone application in the identification of gout flares

OBJECTIVE

To examine the feasibility, preference, and satisfaction of an interactive voice response (IVR) system versus a customized smartphone application (StudyBuddy) to capture gout flares METHODS: In this 24-week prospective, randomized, crossover, open-label pilot study, 44 gout patients were randomized to IVR vs. StudyBuddy and were crossed over to the other technology after 12 weeks. Flares were reported via weekly (and later daily) scheduled StudyBuddy or IVR queries. Feasibility was ascertained via response rate to scheduled queries. At 12 and 24 weeks, participants completed preference/satisfaction surveys. Preference and satisfaction were assessed using dichotomous or ordinal questions. Sensitivity was assessed by the frequency of flare reporting with each approach.

RESULTS

Thirty-eight of 44 participants completed the study. Among completers, feasibility was similar for IVR (81%) and StudyBuddy (80%). Conversely, most (74%) preferred StudyBuddy. Measures of satisfaction (ease of use, preference over in-person clinic visits, and willingness for future use) were similar between the IVR and StudyBuddy; however, more participants deemed the StudyBuddy as convenient (95% vs. 73%, P = 0.01) and less disruptive (97% vs. 82%, P = 0.03). Although the per patient number of weeks in flare was not significantly different (mean 3.4 vs. 2.6 weeks/patient, P = 0.15), the StudyBuddy captured more of the total flare weeks (35%) than IVR (27%, P = 0.02).

CONCLUSION

A smartphone application and IVR demonstrated similar feasibility but overall sensitivity to capture gout flares and participant preference were greater for the smartphone application. Participant preference for the smartphone application appeared to relate to perceptions of greater convenience and lower disruption.

TRIAL REGISTRATION

NCT, NCT02855437 . Registered 4 August 2016.

Difficult-to-treat gout flares: eligibility for interleukin-1 inhibition in private practice is uncommon according to current EMA approval

Objective

The objective was to determine the proportion of patients with difficult-to-treat or difficult-to-prevent acute gout attacks eligible for IL-1 inhibition.

Methods

Participants included in the French cross-sectional GOSPEL cohort (n = 1003 gout patients) were examined for contraindications and intolerance to standard of care (SoC) drugs of gout flares (colchicine, non-steroidal anti-inflammatory drugs and systemic glucocorticoids). Patients were classified as definitely eligible for first-line IL-1 inhibition (canakinumab) according to European summary of product characteristics (contraindications/intolerance to SoC and at least three flares per year) without any other anti-inflammatory options (contraindications/intolerance only), or potentially eligible (precaution of use). Eligibility to receive IL-1 during an on-going flare related to insufficient efficacy was assessed (second-line eligibility).

Results

Definite first-line eligibility for IL-1 therapy was found in 10 patients (1%) and contraindication to all SoC therapies in nine patients who had presented <3 flares in the past 12 months. At least precaution of use for SoC therapies was noted for 218/1003 patients (21.7%). Of 487 patients experiencing flares at baseline, 114 (23.4%) were still experiencing pain scored ⩾4/10 numeric scale on day 3, one of whom could not receive further SoC drugs. Only nine of them had three or more flares in the past year and were eligible for second-line IL-1 inhibition.

Conclusion

Despite significant numbers of patients without any SoC anti-inflammatory therapeutic options for gout flares, eligibility for IL-1 inhibition therapy according to current European approval is rare.

Epigallocatechin-3-Gallate Prevents Acute Gout by Suppressing NLRP3 Inflammasome Activation and Mitochondrial DNA Synthesis

Gout is a chronic inflammatory disease evoked by the deposition of monosodium urate (MSU) crystals in joint tissues. The nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) family pyrin domain containing 3 (NLRP3) inflammasome is responsible for the gout inflammatory symptoms induced by MSU crystals. We investigated whether epigallocatechin-3-gallate (EGCG) suppresses the activation of the NLRP3 inflammasome, thereby effectively preventing gouty inflammation. EGCG blocked MSU crystal-induced production of caspase-1(p10) and interleukin-1β in primary mouse macrophages, indicating its suppressive effect on the NLRP3 inflammasome. In an acute gout mouse model, oral administration of EGCG to mice effectively alleviated gout inflammatory symptoms in mouse foot tissue injected with MSU crystals. The in vivo suppressive effects of EGCG correlated well with the suppression of the NLRP3 inflammasome in mouse foot tissue. EGCG inhibited the de novo synthesis of mitochondrial DNA as well as the production of reactive oxygen species in primary mouse macrophages, contributing to the suppression of the NLRP3 inflammasome. These results show that EGCG suppresses the activation of the NLRP3 inflammasome in macrophages via the blockade of mitochondrial DNA synthesis, contributing to the prevention of gouty inflammation. The inhibitory effects of EGCG on the NLRP3 inflammasome make EGCG a promising therapeutic option for NLRP3-dependent diseases such as gout.

Prognostic factors associated with early gout flare recurrence in patients initiating urate-lowering therapy during an acute gout flare

Lowering serum urate levels below the threshold for crystal formation with urate-lowering therapy (ULT) has been associated with a lower risk for gout flare reoccurrences. However, gout patients on ULT still commonly suffer from recurring gout flares. The purpose of this study was to explore prognostic factors associated with gout flare recurrence within the first 3 months, in gout patients starting ULT during an acute gout flare. Post-hoc analysis of trial data on acute gout patients randomized to either gout flare standard of care or anakinra treatment were used, including baseline demographic, laboratory, clinical, and patient-reported variables, as well as 3-month follow-up data on gout flare recurrences. Only patients starting ULT at baseline were included. Using variable selection based on clinical relevance, univariate, and multivariate binary logistic regression analyses were done to examine predictors of gout flare reoccurrence. A total of 75 patients were included in this study, of which 36 (48%) experienced a gout flare ≤ 3 months post baseline. The multivariate regression analysis revealed that CRP levels > 30 mg/L (OR 9.47) and lack of prophylaxis when starting ULT (OR 11.56) were independently associated with gout flare recurrence. Similar results were found for the univariate regression analyses. Our results show that CRP levels > 30 mg/L and lack of prophylaxis when starting ULT were prognostic factors for early gout flare reoccurrence in patients starting ULT during an acute gout flare. KEY POINTS: • Gout flare recurrences were common within the first 3 months after starting urate-lowering therapy in gout patients. • Intake of prophylaxis when starting ULT had a strong protective effect on gout flare recurrences. • C-reactive protein level > 30 mg/L was an additional prognostic factor for early (≤ 3 months) gout flare reoccurrence in patients starting ULT during an acute gout flare.