OBJECTIVES: To analyze the cost-effectiveness, multinomial expected value of perfect information (mEVPI), and budget impact of certolizumab pegol (CZP) compared to the used first-line subcutaneously administered tumor necrosis factor (TNF) -inhibitors+methotrexate (MTX) and MTX alone in the treatment of moderate-to-severe rheumatoid arthritis (RA) in the Finnish setting. METHODS: An Excel-based, probabilistic life-time Markov cohort model was developed to assess the cost-effectiveness and mEVPI. Treatment efficacy was measured using the ACR-responses (no ACR20, ACR20, ACR50 or ACR70) at three months. ACR estimated response rates were based on adjusted indirect comparison (MTX as the common comparator) of published clinical trials. The health state utilities were estimated from the CZP-trials using regression models. The inpatient days were linked to patients’ HAQ-scores according to published literature. Cost estimates from Finnish sources were used and assessed from payer perspective. Cost and health outcomes were discounted with annual 3% discount rate. Undiscounted budget impact of CZP was estimated for years 2010-2013 using Excel-model. Equal inpatient costs and treatment efficacies were assumed for all TNF-inhibitors. RESULTS: The lifetime costs for CZP+MTX, etanercept+MTX and MTX alone were €179,986; €201,781; and €186,986, respectively. The corresponding QALYs (life-years) were 7.041 (15.697), 6.838 (15.646) and 6.336 (15.547). According to the cost-effectiveness acceptability frontier, CZP+MTX was the optimal treatment option with 58-73% probability of being cost-effective at willingness-to-pay values of €0-30,000 per QALY gained. The respective mEVPI was €5,058-3,701 per patient. Based on clinical responses, CZP+MTX dominated also adalimumab+MTX with 100-85% probability of cost-effectiveness (€0-30,000 per QALY gained; EVPI €0-218 per patient). The introduction of CZP produced annual budgetary net savings of €0.17-0.80 million during 2010-2013 in budget impact analysis. CONCLUSIONS: This analysis shows that, on average, CZP+MTX dominated the other subcutaneously injected TNF-inhibitors considered or MTX alone in the Finish setting. The use of CZP resulted in budgetary net savings.