OP0149 Evaluating the cost-effectiveness of personalized treatment with adalimumab using serum drug level and anti-adalimumab antibodies in rheumatoid arthritis patients
Authors: C. Krieckaert, S.C. Nair, M.T. Nurmohamed, C.J. van Dongen, W.F. Lems, F.P. Lafeber, J.W. Bijlsma, G. Wolbink, P.M. Welsing
Journal: Annals of the Rheumatic Diseases (2013)

<h3>Background</h3> High costs and safety concerns of biologicals warrant rational use of these drugs, preferably tailoring them to the individual patient. <h3>Objectives</h3> To evaluate the cost effectiveness of tailored biological treatment for rheumatoid arthritis (RA) using adalimumab serum drug level (DL) and anti-adalimumab antibodies (ADA) tests. <h3>Methods</h3> In 272 RA patients starting adalimumab treatment, DL, ADA, DAS28 and biological use was measured over 3 years. A treatment protocol for personalized care was defined in which EULAR response, DL and ADA test results at 6 months defined whether adalimumab treatment continued or discontinued, dosing was altered or, in case of non response, a next biological treatment was started. Using a patient level Markov model, outcome in terms of DAS28 and HAQ and biological use for a personalized care group was simulated and compared to the observed drug use and disease course. Mean direct and indirect costs, QALYs (both based on DAS28 and HAQ) and the ICER from a societal and health care perspective with 95 percentile range were calculated. <h3>Results</h3> Effectiveness was higher in the simulated personalized care group and the average difference in QALYs was 3.32 (95 percentile range -4.80 to 11.2). Costs were saved in the personalized care group as compared to usual care group: mean savings €667,513 (95 percentile range -€1,060,260 to -€294,384) and €665,630 (-€1,032,715 to -€319,539) for direct and total costs respectively. In total €643,275 was saved on biological drug costs and testing costs amounted to €12,116. This resulted in an averageICER of -€ 200,916per QALY gained. In 79% of simulations personalized care saved costs and was more effective (dominant) and in 21% cost-saving and less effective. From the healthcare perspective the average ICER was -€6,874/QALY with also 79% of simulations dominant and 21% more expensive and less effective. There was a 99% probability that personalized care is cost-effective from the societal perspective when the willingness to pay for one extra QALY is €20,000. Results of further sensitivity analyses and scenario analyses will follow later. <h3>Conclusions</h3> Tailoring biological treatment to individual RA patients using DL and ADA tests to evaluate short-term outcomes is cost effective. Although these tests were specific to adalimumab, the results underline the potential cost-effectiveness for personalized treatment in RA, specifically with biologicals. <h3>Disclosure of Interest</h3> C. Krieckaert: None Declared, S. Nair: None Declared, M. Nurmohamed Grant/Research support from: Abbott, Roche, Pfizer, Consultant for: Abbott, Roche, Pfizer, MSD, UCB, SOBI, BMS, Speakers Bureau: Abbott, Roche, Pfizer, C. van Dongen: None Declared, W. Lems: None Declared, F. Lafeber: None Declared, J. Bijlsma: None Declared, G. Wolbink Grant/Research support from: Pfizer, Speakers Bureau: Pfizer, Amgen, P. Welsing: None Declared