Rheumatoid Arthritis: Brennan A

Bansback NJ, Young A, Brennan A. · No affiliation provided · Rheumatology (Oxford). · Pubmed #15328422 links to  free full text

This publication has no abstract.

Bansback NJ, Regier DA, Ara R, Brennan A, Shojania K, Esdaile JM, Anis AH, Marra CA. · Health Economics and Decision Science, School of Health and Related Research, University of Sheffield, Sheffield, UK. · Drugs. · Pubmed #15733011 No free full text.

Abstract: Rheumatoid arthritis (RA) is a chronic, progressive, inflammatory disease that affects approximately 0.5-1% of the adult population. The introduction of new disease-modifying antirheumatic drugs (DMARDs) such as leflunomide, anakinra and the tumour necrosis factor (TNF)-alpha antagonists (infliximab, etanercept and adalimumab) have transformed the management of RA. In particular, the last class of agents has generated substantial controversy. Costing between 16,000 US dollars and 20,000 US dollars per patient-year (2001 values), the potential greater efficacy of treatment with TNFalpha antagonists comes at much higher drug costs, making these agents natural candidates for cost-effectiveness analyses (CEAs).A MEDLINE search (until 31 January 2004) identified six original CEAs evaluating TNFalpha antagonists in RA. The aim of a CEA is to facilitate the allocation of scarce health resources and to inform policy decisions. However, to enhance the reliability and relevance of these analyses to policy makers, there must be similarity between the methodologies used. Recently, the OMERACT (Outcome Measures in Rheumatoid Arthritis Clinical Trials) group produced a document to define such a reference case; the OMERACT document was used as a foundation to structure comparisons and highlight discrepancies.The methodologies employed in each analysis differed; in particular, disparate time horizons, comparators, quantities of drug and treatment sequences prohibit the comparison of cost effectiveness between studies. Outcomes also differed between the analyses. Most reported health-related quality of life (HR-QOL) in quality-adjusted life-years (QALYs). The QALYs metric was based on preference scores that were typically derived from linear regressions using the Health Assessment Questionnaire (HAQ). However, models also used American College of Rheumatology (ACR) criteria, as well as the disease activity score (DAS). Common to all studies was the lack of data from long-term randomised studies where efficacy and resource consumption in comparison with standard care has been investigated. As such, investigators combined short-term randomised control trial data with that of a long-term observational cohort, and modelled cost effectiveness over an appropriate time horizon. In addition, most analyses lacked rigorous sensitivity analysis to examine the impact of uncertainty in the parameters.Those analyses that examined time horizons of 6 months and 1 year published incremental cost-effectiveness ratios (ICERs) of 34,800 US dollars per ACR 70% response criteria (ACR70) weighted response (duration 6 months, 1999 values) and 96,166 US dollars (duration 1 year, 2002 values). Analyses that modelled costs and health outcomes beyond the first year reported ICER estimates ranging between 26,800 US dollars (patients' lifetime, 1998 values) and 40,308 US dollars (10 years, 2002 values). In terms of HR-QOL, the analyses reported incremental QALYs that ranged from 0.116 (over 19 years) to 1.6 (over 10 years). Discounted costs of therapy ranged from 30,362 US dollars (10 years, 2002 values) to 93,000 US dollars (22 years, 1998 values), and comparator costs ranged from 22,593 US dollars (10 years, 2002 values) to 84,000 US dollars (22 years, 1998 values).

Nixon RM, Bansback N, Stevens JW, Brennan A, Madan J. · MRC Biostatistics Unit, Institute of Public Health, University Forvie Site, Cambridge, UK. · Pharm Stat. · Pubmed #18942777 No free full text.

Abstract: A model is presented to generate a distribution for the probability of an ACR response at six months for a new treatment for rheumatoid arthritis given evidence from a one- or three-month clinical trial. The model is based on published evidence from 11 randomized controlled trials on existing treatments. A hierarchical logistic regression model is used to find the relationship between the proportion of patients achieving ACR20 and ACR50 at one and three months and the proportion at six months. The model is assessed by Bayesian predictive P-values that demonstrate that the model fits the data well. The model can be used to predict the number of patients with an ACR response for proposed six-month clinical trials given data from clinical trials of one or three months duration.

Wailoo AJ, Bansback N, Brennan A, Michaud K, Nixon RM, Wolfe F. · Health Economics and Decision Science, ScHARR, University of Sheffield, Sheffield, UK. · Arthritis Rheum. · Pubmed #18383356 links to  free full text

Abstract: OBJECTIVE: Since the introduction of the Medicare Prescription Drug Improvement and Modernization Act and its associated demonstration project, coverage of selected biologic drugs has been expanded for Medicare beneficiaries. For rheumatoid arthritis, coverage was extended to etanercept, adalimumab, and anakinra in addition to the previously covered infliximab. We undertook to develop a model to compare the costs and quality-adjusted life years (QALYs) generated by each of the 4 biologic agents. METHODS: Data were drawn from meta-analysis of randomized controlled trials and from a large longitudinal outcomes databank. Uncertainty was addressed using probabilistic and one-way sensitivity analyses. A lifetime horizon and Medicare viewpoint were adopted. RESULTS: In the base case analysis, anakinra was the least effective and least costly strategy. Etanercept, adalimumab, and infliximab were similar in terms of effectiveness, but infliximab was more costly. If decision makers are willing to pay a maximum of $50,000/QALY, the probability that infliximab is cost-effective is <1%. Findings were robust to a range of sensitivity analyses. Only if the dose of infliximab remains constant over time is this likely to be a cost-effective strategy. CONCLUSION: Infliximab is unlikely to be cost-effective in the Medicare population compared with either etanercept or adalimumab. Anakinra is substantially less costly but is also less effective than the 3 tumor necrosis factor alpha inhibitors.

Brennan A, Bansback N, Nixon R, Madan J, Harrison M, Watson K, Symmons D. · Health Economics and Decision Science, School of Health and Related Research (ScHARR), The University of Sheffield, UK. · Rheumatology (Oxford). · Pubmed #17562686 links to  free full text

Abstract: OBJECTIVE: To evaluate the cost effectiveness of TNF-alpha antagonist therapies for rheumatoid arthritis (RA) in the United Kingdom using data from the British Society for Rheumatology Biologics Registry (BSRBR). METHODS: A simulation model is constructed to quantify the cost effectiveness of the TNF-alpha antagonist therapies (infliximab, etanercept and adalimumab) as a group versus traditional disease-modifying anti-rheumatic drugs, with a time horizon over the full patient lifetime. Participants are UK NHS patients in the BSRBR with RA who have failed at least two traditional disease-modifying anti-rheumatic drugs. The BSRBR aims to recruit all RA patients starting on a TNF-alpha antagonist agent and follows them 6 monthly via consultant and patient administered questionnaires. Data collected include disease activity scores (DAS28), the Health Assessment Questionnaire and the SF-36. Costs include drug, monitoring and hospitalisations. Benefits are measured in disability and quality of life improvements. The main outcome measure is the incremental cost per quality adjusted life-year gained (discounted). RESULTS: The basecase cost per quality adjusted life-year gained by using TNF-alpha antagonist therapies is estimated at pound23 882, with probabilistic uncertainty analysis suggesting that the probability that treatments are below 30,000 pounds per QALY is around 84%. The results are most sensitive to assumptions concerning long-term disability progression, discount rates and the validity or otherwise of SF6D derived utility measures. Subgroup analysis, monotherapy versus combination with methotrexate, and a limited analysis of sequential therapy with two TNF-alpha antagonist agents, suggest cost-effectiveness ratios around 20,000 pounds to 30,000 pounds. CONCLUSIONS: The BSRBR data provide valuable evidence for estimating cost-effectiveness. The analysis concludes that current policies and practice for the use of TNF-alpha antagonist therapies, after RA patients have failed at least two traditional disease-modifying anti-rheumatic drugs, appear cost-effective in the context of the NICE re-appraisal of 2006 for England and Wales, thus supporting their decision to continue their reimbursement. Decision-makers worldwide might adapt this analysis because differential costs, discount rates and other factors could affect results. There remains uncertainty, particularly on long-term disease progression. Further data collection using the BSRBR is recommended, together with a revision to this analysis when data become available.

Nixon R, Bansback N, Brennan A. · MRC Biostatistics Unit, Institute of Public Health, University Forvie Site, Robinson Way, Cambridge CB2 2SR, UK. · Rheumatology (Oxford). · Pubmed #17478472 links to  free full text

Abstract: OBJECTIVE: New treatments that inhibit the cytokines tumour necrosis factor alpha (TNFalpha) and interleukin 1 (IL-1) in the treatment of rheumatoid arthritis have proven clinical effect against placebo and methotrexate (MTX) in several clinical trials in early and late-stage disease and different severity groups. Since there are no head-to-head randomized controlled trials directly comparing the currently available treatments, etanercept, adalimumab, infliximab or anakinra, we perform a meta-analysis that adjusts for differences between study characteristics, and allows indirect comparisons between treatments. METHODS: Thirteen trials of cytokine antagonists were included from a systematic review of the literature. They reported the primary outcome of American College of Rheumatology (ACR) response criteria at 6 months or beyond. Meta-analytical methods are used to quantify relative treatment effects, using the log odds ratio of an ACR20 or ACR50 response at 6 months, whilst adjusting for study-level variables. RESULTS: In each of the trials, cytokine treatment was efficacious in comparison with placebo or MTX. For each treatment, the inclusion of MTX in combination improved the response. After adjustment for study-level variables, we found TNFalpha antagonists to be more efficacious compared with anakinra (P < 0.05). Indirect comparisons between the three TNFalpha antagonists indicated no difference in efficacy. Sensitivity analysis using a different statistical model structure confirmed these results. CONCLUSION: When the outcome of interest is the probability of an ACR20 or ACR50 response at 6 months we found: (i) treatment with the IL-1 antagonist anakinra is better than placebo; (ii) for each treatment, the use of combination MTX improves the probability of response; (iii) treatment with any of the TNFalpha antagonists is better than with the IL-1 antagonist anakinra; and (iv) all drugs in the TNFalpha antagonist class are no different from each other.

Nixon RM, Bansback N, Brennan A. · MRC Biostatistics Unit, Institute of Public Health, University Forvie Site, Robinson Way, Cambridge CB2 2SR, U.K. · Stat Med. · Pubmed #16900557 No free full text.

Abstract: Mixed treatment comparison (MTC) is a generalization of meta-analysis. Instead of the same treatment for a disease being tested in a number of studies, a number of different interventions are considered. Meta-regression is also a generalization of meta-analysis where an attempt is made to explain the heterogeneity between the treatment effects in the studies by regressing on study-level covariables. Our focus is where there are several different treatments considered in a number of randomized controlled trials in a specific disease, the same treatment can be applied in several arms within a study, and where differences in efficacy can be explained by differences in the study settings. We develop methods for simultaneously comparing several treatments and adjusting for study-level covariables by combining ideas from MTC and meta-regression.We use a case study from rheumatoid arthritis. We identified relevant trials of biologic verses standard therapy or placebo and extracted the doses, comparators and patient baseline characteristics. Efficacy is measured using the log odds ratio of achieving six-month ACR50 responder status. A random-effects meta-regression model is fitted which adjusts the log odds ratio for study-level prognostic factors. A different random-effect distribution on the log odds ratios is allowed for each different treatment. The odds ratio is found as a function of the prognostic factors for each treatment. The apparent differences in the randomized trials between tumour necrosis factor alpha (TNF- alpha) antagonists are explained by differences in prognostic factors and the analysis suggests that these drugs as a class are not different from each other.

Bansback N, Young A, Brennan A, Dixey J. · Early Rheumatoid Arthritis Study Group, ERAS, Department of Rheumatology, City Hospital, St. Albans, UK. · J Rheumatol. · Pubmed #16832851 No free full text.

Abstract: OBJECTIVE: To construct a prognostic algorithm to predict 5-year functional outcome in rheumatoid arthritis (RA), based on the Health Assessment Questionnaire (HAQ). METHODS: Data from all patients with 5-year followup (n = 985) were used from an inception cohort, the Early Rheumatoid Arthritis Study (ERAS). Possibly relevant prognostic factors considered in the initial stage of the model-building process were standard clinical, radiological, and laboratory features measured at baseline and at 1 year. Multivariate analysis was performed using logistic regression, and the predictive performance of the model was tested using measures of discrimination and calibration. RESULTS: Bootstrap resampling identified 6 variables that consistently predicted severe functional outcome. Functional grade III/IV (odds ratio 6.7) and HAQ at 1 year (odds ratio 2.4) were the most important. Other variables included socioeconomic status, hemoglobin, and radiographic and disease activity scores. Estimates of the regression coefficients and performance were corrected for over-fitting. Reasonably large values for the c-index (0.82) and the Nagelkerke R(2) (0.39) indicate that the set of prognostic factors explains the variation in outcome to a degree that implies good prediction for individual patients. CONCLUSION: The algorithm identifies patients in the first year of RA who are likely to have poor function by 5 years and who could potentially benefit from aggressive drug therapy. A nomogram is produced for simple application of the model in clinical practice. While further external validation is necessary, this model could allow clinicians to target aggressive therapy earlier in a patient's disease course.

Bansback NJ, Brennan A, Ghatnekar O. · Health Economics and Decision Science, ScHARR, University of Sheffield, Regent Court, 40 Regent Street, Sheffield S1 4DA UK. · Ann Rheum Dis. · Pubmed #15550533 links to  free full text

Abstract: BACKGROUND: Societal decision makers increasingly emphasise their need for evidence based economic analyses to make reimbursement decisions. OBJECTIVE: To analyse the cost utility of adalimumab, on both incremental cost and incremental quality adjusted life years (QALYs), versus traditional disease modifying antirheumatic drugs and the other tumour necrosis factor (TNF) antagonists suitable for submission to the Swedish LFN (Pharmaceutical Benefit Board). METHODS: Swedish unit costs and treatment guidelines from a lifetime perspective were implemented. A mathematical model, incorporating data from seven trials, simulated the experiences of 10 000 hypothetical patients with moderate to severe rheumatoid arthritis (RA). The primary outcome measure-QALYs-was derived from utility values calculated from a relationship between the Health Assessment Questionnaire (HAQ) Disability Index (DI) and Health Utility Index-III (HUI-3) from adalimumab trial results. The model followed the progression of HAQ-DI through a number of treatments in a sequence accounting for mortality, drug and monitoring costs, and other direct costs. RESULTS: When using ACR50 as a response threshold for determining successful treatment, adalimumab plus methotrexate showed the greatest number of QALYs gained (2.3 from one study and 2.1 from the pooled results of two trials). The etanercept plus methotrexate strategy yielded QALY gains similar to the pooled adalimumab results. Except for the infliximab strategy, the costs results were between 35 000 and 42 000, a range normally considered cost effective in other European countries. CONCLUSION: Adalimumab appears to be cost effective for the treatment of moderate to severe RA. The results suggest that adalimumab is at least as cost effective as other TNF antagonists.

Brennan A, Bansback N, Reynolds A, Conway P. · Operational Research, School of Health and Related Research, University of Sheffield, Sheffield, South Yorkshire, UK. · Rheumatology (Oxford). · Pubmed #12890861 links to  free full text

Abstract: OBJECTIVES: This model examines the cost-effectiveness of etanercept monotherapy under British Society for Rheumatology guidelines, i.e. adults previously failing two disease-modifying anti-rheumatic drugs (DMARDs). It compares a DMARD sequence with etanercept third line against the same sequence excluding etanercept. METHOD: The 6-monthly trend in Health Assessment Questionnaire (HAQ) disability score is simulated for 10 000 patients' lifetimes using clinical trial data and published literature. Switching to the next treatment is triggered by lack of response, loss of efficacy or adverse events. Patient mortality depends on rheumatoid arthritis life-tables and on epidemiological evidence relating reduced risk to HAQ improvement. Regression of HAQ/EuroQol (EQ-5D) utility provides quality-adjusted life years (QALY) gained. Primary analysis includes drug costs, monitoring and hospitalizations. RESULTS: The central estimate cost per QALY is pound 16 330. Sensitivity analyses ( pound 7800 to pound 42 000) showed long-term HAQ progression (etanercept, DMARDs, non-responders) as most sensitive variables. The inclusion of potential avoided nursing home admissions and indirect costs/lost employment further improves the cost-effectiveness. CONCLUSIONS: For adults in the UK, the results suggest that etanercept is cost-effective when compared with non-biologic agents. The National Institute for Clinical Excellence has accepted that etanercept is cost-effective and recommended its availability for use in patients who have failed at least two DMARDs. This model was an important component of that decision. The model is further suitable for use for a wide range of other cost-effectiveness questions in rheumatoid arthritis.