FRI0563 Cost-effectiveness of tnf inhibitors in combination with synthetic dmards versus synthetic dmards alone in patients with ra: results from nor-dmard and orar
Authors: M. K. Kvamme, E. Lie, T. Uhlig, T. K. Kvien, T. A. Moger, I. S. Kristiansen
Journal: Annals of the Rheumatic Diseases (2013)

<h3>Background</h3> Biologic disease modifying antirheumatic drugs (DMARDs) entail considerable improvement in patient outcomes for patients with rheumatoid arthritis (RA), but the treatment is costly. Several model studies have explored the cost-effectiveness of TNF inhibitors (TNFi), but the results have been conflicting in that some studies conclude that biologics are cost-effective while others do not. Most models are based on clinical trial data with limited generalizability to real life outcomes. <h3>Objectives</h3> To use real life register data to estimate the additional costs and additional health benefits of replacing synthetic DMARDs alone with a combination of TNF inhibitors (TNFi) and synthetic DMARDs. <h3>Methods</h3> We developed a Markov model to explore two treatment strategies for patients with RA: TNFi plus synthetic DMARD (TNFi-strategy) and synthetic DMARD alone (synthetic-strategy). Patients in both strategies started in one of seven health states defined on the basis of SF-6D utilities (0.30-0.39, 0.40-0.49 …. 0.90-1.00). The patients could subsequently move to better or worse utility levels according to transition probabilities which varied over time. The model had a 10-year perspective and a cycle length of three months. In the TNFi-strategy, patients could stay on TNFi (incl. TNFi cycling), or switch to non-TNFi-biologics, synthetic DMARDs or no DMARDs. In the synthetic-strategy, patients remained on the same therapy, but could change utility levels. In both strategies we assumed a standardized mortality ratio of 1.54 using mortality statistics from Norway. Transition probabilities for the TNFi-strategy were derived from the Norwegian longitudinal observational study on disease-modifying antirheumatic drugs (NOR-DMARD) using 810 RA-patients who started TNFi-treatment after failure on 2.1 synthetic DMARDs on average. Patients were followed from 2000 to 2011 with a mean follow-up time of 3.6 years. Data from Oslo Rheumatoid Arthritis register (ORAR) were used for the synthetic-strategy. All cost data (pharmaceuticals, hospital care, GP and physiotherapist visits, indirect costs, <i>etc.</i>) were taken from NOR-DMARD[1]. SF-36 data were taken from NOR-DMARD and ORAR and translated into SF-6D utilities. Future cost and outcomes were discounted at the nationally recommend rate of 4% per year. For the sensitivity analyses, Dirichlet distributions were used to express uncertainty in the Markov transition probabilities. <h3>Results</h3> Ten-year discounted costs of a patient on the TNFi-strategy totaled €129,090 (€470,709 including indirect costs) while the synthetic-strategy led to costs of €52,765 (€415,434). The strategies entailed 5.42 and 4.78 quality adjusted life years (QALYs) (6.51 and 5.73 undiscounted), respectively, representing €118,802 per gained QALY (€86,079 when indirect costs were included). The latter ratio is below the suggested willingness-to-pay for a QALY (€40,300 to €107,600) in Norway. In probabilistic sensitivity analysis, the probability that the combined TNFi and synthetic DMARD is cost-effective (&lt; €107,600 per QALY) was 100% when including indirect costs. <h3>Conclusions</h3> TNFi treatment of RA in a 10-year perspective appears to be cost-effective when indirect costs are accounted for in a setting of real life data. <h3>References</h3> Kvamme MK et al. <i>Rheumatology (Oxford).</i>2012;<b>51</b>:1618-27. <h3>Disclosure of Interest</h3> M. Kvamme Grant/research support from: A course in Paris, France 12-14 of September 2012 payed by Pfizer and organized by the International value coalition., E. Lie Consultant for: Speaker/consulting honoraria Pfizer, BMS, Abbott og Roche, T. Uhlig Consultant for: honorary/Speaker/consulting: Abbott, BMS, MSD, Pfizer, Roche, UCB, T. Kvien Grant/research support from: Research grants received to Diakonhjemmet Hospital from: Abbott, BMS, MSD/Schering-Plough, Pfizer/Wyeth, Roche, UCB, Consultant for: Consultancy fees: Abbott, BMS, MSD/Schering-Plough, Nicox, Pfizer/Wyeth, Roche, UCB, Schering-Plough, UCB, Wyeth, Speakers bureau: Speaker honoraria: Abbott, AstraZeneka, MSD/Schering-Plough, Nicox, Pfizer/Wyeth, Roche, UCB, Schering-Plough, UCB, Wyeth, T. Moger: None Declared, I. Kristiansen: None Declared