M3C: Monte Carlo reference-based consensus clustering.

Genome-wide data is used to stratify patients into classes for precision medicine using clustering algorithms. A common problem in this area is selection of the number of clusters (K). The Monti consensus clustering algorithm is a widely used method which uses stability selection to estimate K. However, the method has bias towards higher values of K and yields high numbers of false positives. As a solution, we developed Monte Carlo reference-based consensus clustering (M3C), which is based on this algorithm. M3C simulates null distributions of stability scores for a range of K values thus enabling a comparison with real data to remove bias and statistically test for the presence of structure. M3C corrects the inherent bias of consensus clustering as demonstrated on simulated and real expression data from The Cancer Genome Atlas (TCGA). For testing M3C, we developed clusterlab, a new method for simulating multivariate Gaussian clusters.

Validity of a two-component imaging-derived disease activity score for improved assessment of synovitis in early rheumatoid arthritis.

OBJECTIVES: Imaging of joint inflammation provides a standard against which to derive an updated DAS for RA. Our objectives were to develop and validate a DAS based on reweighting the DAS28 components to maximize association with US-assessed synovitis. METHODS: Early RA patients from two observational cohorts (n = 434 and n = 117) and a clinical trial (n = 59) were assessed at intervals up to 104 weeks from baseline; all US scans were within 1 week of clinical exam. There were 899, 163 and 183 visits in each cohort. Associations of combined US grey scale and power Doppler scores (GSPD) with 28 tender joint count and 28 swollen joint count (SJC28), CRP, ESR and general health visual analogue scale were examined in linear mixed model regressions. Cross-validation evaluated model predictive ability. Coefficients learned from training data defined a re-weighted DAS28 that was validated against radiographic progression in independent data (3037 observations; 717 patients). RESULTS: Of the conventional DAS28 components only SJC28 and CRP were associated with GSPD in all three development cohorts. A two-component model including SJC28 and CRP outperformed a four-component model (R2 = 0.235, 0.392, 0.380 vs 0.232, 0.380, 0.375, respectively). The re-weighted two-component DAS28CRP outperformed conventional DAS28 definitions in predicting GSPD (Δtest log-likelihood <-2.6, P < 0.01), Larsen score and presence of erosions. CONCLUSION: A score based on SJC28 and CRP alone demonstrated stronger associations with synovitis and radiographic progression than the original DAS28 and should be considered in research on pathophysiological manifestations of early RA. Implications for clinical management of RA remain to be established.

Feasibility randomised multicentre, double-blind, double-dummy controlled trial of anakinra, an interleukin-1 receptor antagonist versus intramuscular methylprednisolone for acute gout attacks in patients with chronic kidney disease (ASGARD): protocol study.

INTRODUCTION: Acute gout occurs in people with chronic kidney disease, who are commonly older people with comorbidities such as hypertension, heart disease and diabetes. Potentially harmful treatments are administered to these vulnerable patients due to a lack of clear evidence. Newly available treatment that targets a key inflammatory pathway in acute gout attacks provides an opportunity to undertake the first-ever trial specifically looking treating people with kidney disease. This paper describes the protocol for a feasibility randomised controlled trial (RCT) comparing anakinra, a novel interleukin-1 antagonist versus steroids in people with chronic kidney disease (ASGARD). METHODS AND ANALYSIS: ASGARD is a two-parallel group double-blind, double-dummy multicentre RCT comparing anakinra 100 mg, an interleukin-1 antagonist, subcutaneous for 5 days against intramuscular methylprednisolone 120 mg. The primary objective is to assess the feasibility of the trial design and procedures for a definitive RCT. The specific aims are: (1) test recruitment and retention rates and willingness to be randomised; (2) test eligibility criteria; (3) collect and analyse outcome data to inform sample and power calculations for a trial of efficacy; (4) collect economic data to inform a future economic evaluation estimating costs of treatment and (5) assess capacity of the project to scale up to a national multicentre trial. We will also gather qualitative insights from participants. It aims to recruit 32 patients with a 1:1 randomisation. Information from this feasibility study will help design a definitive trial and provide general information in designing acute gout studies. ETHICS AND DISSEMINATION: The London-Central Ethics Committee approved the protocol. The results will be disseminated in peer-reviewed journals and at scientific conferences. TRIAL REGISTRATION NUMBER: EudraCT No. 2015-001787-19, NCT/Clinicalstrials.gov No. NCT02578394, pre-results, WHO Universal Trials Reference No. U1111-1175-1977. NIHR Grant PB-PG-0614-34090.

Randomized Controlled Trial of Rituximab and Cost-Effectiveness Analysis in Treating Fatigue and Oral Dryness in Primary Sjögren's Syndrome.

OBJECTIVE: To investigate whether rituximab, an anti-B cell therapy, improves symptoms of fatigue and oral dryness in patients with primary Sjögren's syndrome (SS). METHODS: We conducted a multicenter, randomized, double-blind, placebo-controlled, parallel-group trial that included health economic analysis. Anti-Ro-positive patients with primary SS, symptomatic fatigue, and oral dryness were recruited from 25 UK rheumatology clinics from August 2011 to January 2014. Patients were centrally randomized to receive either intravenous (IV) placebo (250 ml saline) or IV rituximab (1,000 mg in 250 ml saline) in 2 courses at weeks 0, 2, 24, and 26, with pre- and postinfusion medication including corticosteroids. The primary end point was the proportion of patients achieving a 30% reduction in either fatigue or oral dryness at 48 weeks, as measured by visual analog scale. Other outcome measures included salivary and lacrimal flow rates, quality of life, scores on the European League Against Rheumatism (EULAR) Sjögren's Syndrome Patient Reported Index and EULAR Sjögren's Syndrome Disease Activity Index, symptoms of ocular and overall dryness, pain, globally assessed disease activity, and cost-effectiveness. RESULTS: All 133 patients who were randomized to receive placebo (n = 66) or rituximab (n = 67) were included in the primary analysis. Among patients with complete data, 21 of 56 placebo-treated patients and 24 of 61 rituximab-treated patients achieved the primary end point. After multiple imputation of missing outcomes, response rates in the placebo and rituximab groups were 36.8% and 39.8%, respectively (adjusted odds ratio 1.13 [95% confidence interval 0.50, 2.55]). There were no significant improvements in any outcome measure except for unstimulated salivary flow. The mean ± SD costs per patient for rituximab and placebo were £10,752 ± 264.75 and £2,672 ± 241.71, respectively. There were slightly more adverse events (AEs) reported in total for rituximab, but there was no difference in serious AEs (10 in each group). CONCLUSION: The results of this study indicate that rituximab is neither clinically effective nor cost-effective in this patient population.

Tumour necrosis factor inhibition versus rituximab for patients with rheumatoid arthritis who require biological treatment (ORBIT): an open-label, randomised controlled, non-inferiority, trial.

BACKGROUND: Tumour necrosis factor (TNF) inhibition and B-cell depletion are highly effective treatments for active rheumatoid arthritis, but so far no randomised controlled trials have directly compared their safety, efficacy, and cost-effectiveness. This study was done to test the hypothesis that using rituximab would be clinically non-inferior and cheaper compared with TNF inhibitor treatment in biological-treatment naive patients with rheumatoid arthritis. METHODS: This open-label, randomised controlled, non-inferiority trial enrolled patients with active, seropositive rheumatoid arthritis and an inadequate response to synthetic disease modifying anti-rheumatic drugs (DMARDs) from 35 rheumatology departments in the UK. Patients were randomly assigned 1:1 to the rituximab or TNF inhibitor groups with minimisation to account for methotrexate intolerance using a web-based randomisation system. Patients were given intravenous rituximab 1 g on days 1 and 15, and after 26 weeks if they responded to treatment but had persistent disease activity (28 joint count disease activity score [DAS28-ESR] >3.2; rituximab group) or a TNF inhibitor-adalimumab (40 mg subcutaneously every other week) or etanercept (50 mg per week subcutaneously) according to the patient's and rheumatologist's choice (TNF inhibitor group). Patients could switch treatment in the case of drug-related toxic effects or absence or loss of response. The primary outcome measure was the change in DAS28-ESR between 0 and 12 months in the per-protocol population of patients who were assigned to treatment and remained in follow-up to 1 year. We assessed safety in all patients who received at least one dose of study drug. We also assessed the cost-effectiveness of each strategy. The non-inferiority margin was specified as 0.6 DAS28-ESR units. This study is registered with ClinicalTrials.gov, number NCT01021735. FINDINGS: Between April 6, 2009, and Nov 11, 2013, 295 patients were randomly assigned and given either rituximab (n=144) or TNF inhibitor (n=151) treatment. After 12 months, the change in DAS28-ESR for patients assigned to rituximab was -2.6 (SD 1.4) and TNF inhibitor was -2.4 (SD 1.5), with a difference within the prespecified non-inferiority margin of -0.19 (95% CI -0.51 to 0.13; p=0.24). The health-related costs associated with the rituximab strategy were lower than the TNF inhibitor strategy (£9,405 vs £11,523 per patient, p<0.0001). 137 (95%) of 144 patients in the rituximab group and 143 (95%) of 151 patients in the TNF inhibitor group had adverse events. 37 serious adverse events occurred in patients receiving rituximab compared with 26 in patients receiving TNF inhibitors, of which 27 were deemed to be possibly, probably, or definitely related to the treatment (15 vs 12, p=0.5462). One patient in each group died during the study. INTERPRETATION: Initial treatment with rituximab is non-inferior to initial TNF inhibitor treatment in patients seropositive for rheumatoid arthritis and naive to treatment with biologicals, and is cost saving over 12 months. FUNDING: Arthritis Research UK, Roche.

Trojan horses and guided missiles: targeted therapies in the war on arthritis.

Despite major advances in the treatment of rheumatoid arthritis (RA) led by the success of biologic therapies, the lack of response to therapy in a proportion of patients, as well as therapy discontinuation owing to systemic toxicity, are still unsolved issues. Unchecked RA might develop into progressive structural joint damage, loss of function and long-term disability, disorders which are associated with a considerable health-economic burden. Therefore, new strategies are required to actively target and deliver therapeutic agents to disease sites in order to promote in situ activity and decrease systemic toxicity. Polymer-drug conjugates can improve the pharmacokinetics of therapeutic agents, conferring desirable properties such as increased solubility and tissue penetration at sites of active disease. Additionally, nanotechnology is an exciting modality in which drugs are encapsulated to protect them from degradation or early activation in the circulation, as well as to reduce systemic toxicity. Together with the targeting capacity of antibodies and site-specific peptides, these approaches will facilitate selective accumulation of therapeutic agents in the inflamed synovium, potentially improving drug efficacy at disease sites without affecting healthy tissues. This Review aims to summarize key developments in the past 5 years in polymer conjugation, nanoparticulate drug delivery and antibody or peptide-based targeting--strategies that might constitute the platform for the next generation of RA therapeutics.

Autonomic symptoms are common and are associated with overall symptom burden and disease activity in primary Sjogren's syndrome.

OBJECTIVES: To determine the prevalence of autonomic dysfunction (dysautonomia) among patients with primary Sjögren's syndrome (PSS) and the relationships between dysautonomia and other clinical features of PSS. METHODS: Multicentre, prospective, cross-sectional study of a UK cohort of 317 patients with clinically well-characterised PSS. Symptoms of autonomic dysfunction were assessed using a validated instrument, the Composite Autonomic Symptom Scale (COMPASS). The data were compared with an age- and sex-matched cohort of 317 community controls. The relationships between symptoms of dysautonomia and various clinical features of PSS were analysed using regression analysis. RESULTS: COMPASS scores were significantly higher in patients with PSS than in age- and sex-matched community controls (median (IQR) 35.5 (20.9-46.0) vs 14.8 (4.4-30.2), p<0.0001). Nearly 55% of patients (vs 20% of community controls, p<0.0001) had a COMPASS score >32.5, a cut-off value indicative of autonomic dysfunction. Furthermore, the COMPASS total score correlated independently with EULAR Sjögren's Syndrome Patient Reported Index (a composite measure of the overall burden of symptoms experienced by patients with PSS) (ß=0.38, p<0.001) and disease activity measured using the EULAR Sjögren's Syndrome Disease Activity Index (ß=0.13, p<0.009). CONCLUSIONS: Autonomic symptoms are common among patients with PSS and may contribute to the overall burden of symptoms and link with systemic disease activity.

Immunohistological assessment of the synovial tissue in small joints in rheumatoid arthritis: validation of a minimally invasive ultrasound-guided synovial biopsy procedure.

The aim of the present study was to perform an immunohistological assessment of the synovial tissue from involved small joints in rheumatoid arthritis (RA) and to explore the reliability of a mini-invasive ultrasound (US)-guided technique of small joint synovial biopsy for the histopathological assessment. Synovial tissue collected during arthrotomic surgery of small joints in nine patients served as the gold standard for the validation of the histological assessment. Small hand-joint synovial biopsies from an additional nine patients with erosive RA were obtained by a mini-invasive US-guided procedure, performed percutaneously by the portal and rigid forceps technique. Using digital image analysis, the area fractions of synovial macrophages (CD68 cells), T cells (CD3 cells) and B cells (CD20 cells) were measured in all high-power fields of every sample at different cutting levels. The representative sample was defined as the minimal number of high-power fields whose mean area fraction would reflect the overall mean area fraction within a percentage mean difference of 10%. For each patient, a range of three to five large samples for surgical biopsies and a range of 8-12 samples for US-guided biopsies were collected and analysed. In arthrotomic samples, the analysis of a randomly selected tissue area of 2.5 mm2 was representative of the overall value for CD68, CD3 and CD20 cells. US-guided samples allowed histological evaluation in 100% of cases, with a mean valid area of 18.56 mm2 (range 7.29-38.28 mm2). The analysis of a cumulative area of 2.5 mm2 from eight randomly selected sections (from different samples or from different cutting levels) allowed to reduce the percentage mean difference to less than 10% for CD68, CD3 and CD20 cells. In conclusion, US-guided synovial biopsy represents a reliable tool for the assessment of the histopathological features of RA patients with a mini-invasive approach.