OP0301 Two year cost-effectiveness analysis of the carera trial in early ra: a piggy back study
Authors: S.S. Pazmino, R. Westhovens, J. Joly, V. Stouten, D. De Cock, K. Van der Elst, P. Verschueren
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> Rheumatoid arthritis (RA) causes high individual, medical and societal costs. EULAR guidelines suggest treating early, intensively and to target using disease modifying anti-rheumatic drugs (DMARDs), preferably with initial glucocorticoid (GC) bridging. COBRA slim, a combination of methotrexate (MTX) with a moderate dose prednisone step down bridge scheme showed a positive efficacy/tolerability balance in the Care in early RA (CareRA) trial. COBRA Slim in comparison to DMARD combination therapy with GC bridging, has the necessary intensity to induce remission, but with a lower risk of severe discomfort or adverse events, decreasing the early need for biologic (b)DMARDs. <h3>Objectives</h3> Perform an economic evaluation on the 2 year pragmatic randomised CareRA trial. <h3>Methods</h3> Patients with early RA (≤1 year) naïve to DMARDs were randomised to monotherapy or synthetic (cs)DMARD combination with or without GC bridging, after risk stratification based on classical prognostic markers. Clinical and patient-reported data were collected at each visit (≥10 times in 2 years). Direct costs of visits and RA medication (systemic GCs, cs and bDMARDs) over 2 years were calculated for each patient from each of the 5 treatment arms (table 1). For cost-effectiveness analysis, benefits were expressed as the proportion of patients with DAS28CRP&lt;2.6 at year 2. Missing data was imputed per item with expectation maximisation. For cost-utility analysis, utilities were calculated using a validated mapping algorithm reconstructing EQ-5D scores based on age, sex, HAQ and pain scores at relevant study visits. Quality-adjusted life years (QALYs) encapsulating the impact of treatment on a patient’s length of life and health-related quality of life, were calculated as the time-weighted average of all available EQ-5D scores (area under the curve). Incremental cost-effectiveness ratios (ICERs) from each strategy were calculated. ICERs compare the additional costs a strategy imposes over another with the additional benefits it delivers. Means and medians based methods were calculated with confidence intervals via bootstrapping. <h3>Results</h3> From the initial CareRA cohort (n=379),cost/benefit data of 326 patients was used for a 2 year economic analysis. The mayor driver of direct costs was bDMARDs (57%&gt;87% of total costs). Number of consultations were comparable (±11) across all treatment strategies. The cost-effectiveness analysis in the high risk population showed a higher ICER for COBRA Avant Garde (mean €198.65/1%, median €78.41/1%) and a dominated ICER for COBRA Classic (mean €-181.40/1%, median €-35.01/1%) compared to the Slim. In the low risk arm, ICERs for COBRA Slim compared to Tight Step Up (TSU) were €46.75/1% (mean) and €43.64/1% (median). Cost-utility analysis in the high risk arm showed an incremental cost of €1 469.36 for an increased utility of 0.012555 QALYS for COBRA Classic compared to COBRA Slim, resulting in an ICER of €117 033.85/QALY. The ICER of COBRA Avant Garde vs COBRA Slim was €69 329.19/QALY. In the low risk arm, the comparison of COBRA Slim to TSU yields an ICER of €1 342.78 per QALY. <h3>Conclusions</h3> COBRA Slim which consists of an initial combination of MTX and a moderate dosed GC remission induction scheme has a favourable cost-effective and cost-utility profile for patients with early RA independent of their prognostic factors. <h3>Disclosure of Interest</h3> S. Pazmino: None declared, R. Westhovens: None declared, J. Joly: None declared, V. Stouten: None declared, D. De Cock: None declared, K. Van der Elst: None declared, P. Verschueren Grant/research support from: Unrestricted Pfizer Chair in the management of early rheumatoid arthritis