Publications (57) View all
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Article: Predictors of mortality in connective tissue disease-associated pulmonary arterial hypertension: a cohort study.
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ABSTRACT: INTRODUCTION: Pulmonary arterial hypertension (PAH) is a major cause of mortality in the connective tissue diseases (CTD). We sought to quantify survival and determine factors predictive of mortality in a cohort of patients with CTD-associated PAH (CTD-PAH) in the current era of advanced PAH therapy. METHODS: Patients with right heart catheter proven CTD-PAH were recruited from 6 specialised PAH treatment centres across Australia and followed prospectively. Using survival methods including Cox proportional hazards regression, we modelled for all-cause mortality. Independent variables included demographic, clinical and hemodynamic data. RESULTS: Among 117 patients (104 [94.9%] with systemic sclerosis), during 2.6 1.8 (mean +/- SD) years of follow-up from PAH diagnosis, there were 32 (27.4%) deaths. One-, two- and three-year survivals were 94%, 89% and 73%, respectively. In multiple regression analysis, higher mean right atrial pressure (mRAP) at diagnosis (hazard ratio [HR]=1.13, 95% CI: 1.04-1.24, P=0.007), lower baseline 6-minute walk distance (HR=0.64, 95% CI: 0.43-0.97, P=0.04), higher baseline World Health Organization functional class (HR=3.42, 95% CI: 1.25-9.36, P=0.04) and presence of a pericardial effusion (HR=3.39, 95% CI: 1.07-10.68, P=0.04) were predictive of mortality. Warfarin (HR=0.20, 95% CI: 0.05-0.78, P=0.02) and combination PAH therapy (HR=0.20, 95% CI: 0.05-0.83, P=0.03) were protective. CONCLUSIONS: In this cohort of CTD-PAH patients, three-year survival was 73%. Independent therapeutic predictors of survival included warfarin and combination PAH therapy. Our findings suggest that anticoagulation and combination PAH therapy may improve survival in CTD-PAH. This observation merits further evaluation in randomised controlled trials.Arthritis research & therapy 10/2012; 14(5):R213. · 4.27 Impact Factor -
Article: Prevalence, correlates and clinical usefulness of antibodies to RNA polymerase III in systemic sclerosis: a cross-sectional analysis of data from an Australian cohort.
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ABSTRACT: The prevalence of antibodies to RNA polymerase III (anti-RNAP) differs among systemic sclerosis (SSc) cohorts worldwide. Previously reported associations of anti-RNAP include diffuse cutaneous disease, tendon friction rubs and renal crisis, with recent reports suggesting a close temporal association between malignancy and SSc disease onset among patients with anti-RNAP. Patients with SSc were tested for the presence of anti-RNAP at recruitment into the Australian Scleroderma Cohort Study. We used univariate and multivariable methods to identify and quantify clinical and laboratory correlates of anti-RNAP in SSc. Diagnostic testing procedures were used to determine the usefulness of these antibodies in estimating the likelihood of clinically important outcomes. There were 451 patients with mean ± standard deviation age and disease duration at recruitment of 58.1 ± 12.4 and 11.6 ± 10.0 years, respectively; 151 (33.5%) patients were recruited within 5 years of diagnosis of SSc. Overall, 69 (15.3%) patients had anti-RNAP. Univariate associations of anti-RNAP were diffuse disease (75.4% vs. 20.9%, P < 0.0001), joint contractures (73.9% vs. 30.1%, P < 0.0001), greater highest-recorded modified Rodnan skin score (20.6 ± 12.4 vs. 10.1 ± 7.9, P < 0.0001), synovitis (31.9% vs. 19.9%, P = 0.03), myositis (2.9% vs. 0.5%, P = 0.05), systemic hypertension (59.4% vs. 39.7%, P = 0.002), renal crisis (24.6% vs. 1.8%, P < 0.0001) and malignancy diagnosed within 5 years of onset of SSc skin disease (13.3% vs. 3.9%, P = 0.01). In multiple regression analysis, after adjustment for other covariates, anti-RNAP were independently associated with renal crisis (odds ratio (OR) 3.8, 95% confidence interval (CI) 1.2 to 11.5, P = 0.02; positive predictive value (PPV) 24.6%, negative predictive value (NPV) 98.2%), diffuse disease (OR 6.4, 95% CI 2.9 to 13.8, P < 0.0001; PPV 75.4%, NPV 20.9%), joint contractures (OR 2.5, 95% CI 1.2 to 5.3, P = 0.02; PPV 73.9%, NPV 69.9%) and malignancy diagnosed within 5 years of onset of SSc skin disease (OR 4.2, 95% CI 1.3 to 13.4, P = 0.01; PPV 13.3%, NPV 96.1%). Anti-RNAP status is a clinically useful prognostic marker in SSc and enables clinicians to identify patients at high risk of developing renal crisis, synovitis, myositis and joint contractures. Patients with anti-RNAP also have an increased risk of malignancy within a 5-year timeframe before or after onset of SSc skin changes.Arthritis research & therapy 12/2011; 13(6):R211. · 4.27 Impact Factor -
Article: A randomized, double-blind study of AMG 108 (a fully human monoclonal antibody to IL-1R1) in patients with osteoarthritis of the knee.
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ABSTRACT: AMG 108 is a fully human, immunoglobulin subclass G2 (IgG2) monoclonal antibody that binds the human interleukin-1 (IL-1) receptor type 1, inhibiting the activity of IL-1a and IL-1b. In preclinical studies, IL-1 inhibition was shown to be beneficial in models of osteoarthritis (OA). The purpose of this two-part study was to evaluate the safety and pharmacokinetics (PK; Part A) and clinical effect (Part B) of AMG 108 in a double-blind, placebo-controlled, multiple-dose study in patients with OA of the knee. In Part A, patients received placebo or AMG 108 subcutaneously (SC; 75 mg or 300 mg) or intravenously (IV; 100 mg or 300 mg) once every 4 weeks for 12 weeks; in Part B, patients received placebo or 300 mg AMG 108 SC, once every 4 weeks for 12 weeks. The clinical effect of AMG 108 was measured in Part B by using the Western Ontario and McMaster Universities (WOMAC) osteoarthritis index pain score. In Part A, 68 patients were randomized, and 64 received investigational product. In Part B, 160 patients were randomized, and 159 received investigational product. AMG 108 was well tolerated. Most adverse events (AEs), infectious AEs, serious AEs and infections, as well as withdrawals from the study due to AEs occurred at similar rates in both active and placebo groups. One death was reported in an 80-year-old patient (Part A, 300 mg IV AMG 108; due to complications of lobar pneumonia). AMG 108 serum concentration-time profiles exhibited nonlinear PK. The AMG 108 group in Part B had statistically insignificant but numerically greater improvement in pain compared with the placebo group, as shown by the WOMAC pain scores (median change, -63.0 versus -37.0, respectively). The safety profile of AMG 108 SC and IV was comparable with placebo in patients with OA of the knee. Patients who received AMG 108 showed statistically insignificant but numerically greater improvements in pain; however, minimal, if any, clinical benefit was observed. This study is registered with ClinicalTrials.gov with the identifier NCT00110942.Arthritis research & therapy 07/2011; 13(4):R125. · 4.27 Impact Factor -
Article: Quantitation of total and free teriflunomide (A77 1726) in human plasma by LC-MS/MS.
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ABSTRACT: The clinical activity of leflunomide, a drug used in the treatment of rheumatoid arthritis, is due to its active metabolite, teriflunomide. In vitro studies indicate that at least 99% of teriflunomide is expected to be protein bound in human plasma in vivo, leaving<1% in the unbound or 'free' state for clinical activity. To examine details of the relationships between leflunomide dosing and patient response, it is necessary to have an assay that is sufficiently sensitive to measure the minor fraction of free teriflunomide in patient samples. Therefore, we aimed to develop and validate an LC-MS/MS method for the measurement of teriflunomide, and use it to determine the total and free teriflunomide concentration in patients with rheumatoid arthritis. Teriflunomide and its deuterated internal standard were extracted from human plasma and separated using a reversed phase method with a C18 column. Detection was conducted with an API 3000 LC-MS/MS System by monitoring selected ions in negative ion MRM. Optimal detection occurred at m/z 269.1/160.0 (teriflunomide) and m/z 273.1/164.0 (teriflunomide-D4). Over a linear range of 5-500 μg/L, the inter-batch precision ranged from 1.9 to 8.8% and accuracy from -8.4 to 8.0%. The intra- and inter-batch assay precision for quality control samples ranged from 2.1-5.4% and 5.7-7.1% respectively. The procedure was applied to assess total and free plasma concentrations of teriflunomide in patients with rheumatoid arthritis. Free teriflunomide was approximately 0.11% of total teriflunomide, and there was a significant correlation (r2=0.724) between free and total teriflunomide concentrations. A validated, accurate and sensitive method was developed and successfully applied for the measurement of total and free teriflunomide concentration in human plasma samples. This method has been shown to be reproducible and sensitive and can be applied to clinical samples.Journal of pharmaceutical and biomedical analysis 02/2011; 55(2):325-31. · 2.45 Impact Factor -
Article: Fish oil and rheumatoid arthritis: past, present and future.
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ABSTRACT: Meta- and mega-analysis of randomised controlled trials indicate reduction in tender joint counts and decreased use of non-steroidal anti-inflammatory drugs with fish-oil supplementation in long-standing rheumatoid arthritis (RA). Since non-steroidal anti-inflammatory drugs confer cardiovascular risk and there is increased cardiovascular mortality in RA, an additional benefit of fish oil in RA may be reduced cardiovascular risk via direct mechanisms and decreased non-steroidal anti-inflammatory drug use. Potential mechanisms for anti-inflammatory effects of fish oil include inhibition of inflammatory mediators (eicosanoids and cytokines), and provision of substrates for synthesis of lipid suppressors of inflammation (resolvins). Future studies need progress in clinical trial design and need to shift from long-standing disease to examination of recent-onset RA. We are addressing these issues in a current randomised controlled trial of fish oil in recent-onset RA, where the aim is to intervene before joint damage has occurred. Unlike previous studies, the trial occurs on a background of drug regimens determined by an algorithm that is responsive to disease activity and drug intolerance. This allows drug use to be an outcome measure whereas in previous trial designs, clinical need to alter drug use was a 'problem'. Despite evidence for efficacy and plausible biological mechanisms, the limited clinical use of fish oil indicates there are barriers to its use. These probably include the pharmaceutical dominance of RA therapies and the perception that fish oil has relatively modest effects. However, when collateral benefits of fish oil are included within efficacy, the argument for its adjunctive use in RA is strong.Proceedings of The Nutrition Society 08/2010; 69(3):316-23. · 2.77 Impact Factor
