Background: Baricitinib is an oral janus kinase inhibitor for the treatment of rheumatoid arthritis (RA) and is approved in Europe for use in adults with moderately-to-severely active RA and an inadequate response or intolerance to conventional synthetic disease-modifying antirheumatic drug (csDMARD) therapy. To date, no economic evaluations have assessed the cost-effectiveness of baricitinib in the Spanish setting. Objectives: To evaluate the cost-effectiveness of baricitinib versus adalimumab for the treatment of moderately-to-severely active RA in the Spanish setting. Methods: A discrete event simulation model was developed in Microsoft Excel. Costs and outcomes were estimated over a lifetime horizon using the Spanish national payer perspective. The model compared baricitinib 4 mg once daily in combination with methotrexate with adalimumab 40 mg every other week in combination with methotrexate. Effectiveness and physical function were captured using the American College of Rheumatology criteria and the Health Assessment Questionnaire-Disability Index, input values of which were derived from a phase 3, double-blind, placebo- and active-controlled trial (RA-BEAM; funded by Eli Lilly and Incyte; ClinicalTrials.gov number, NCT01710358). Costs are presented in Euros, 2018 values. Results: In the base case analysis, baricitinib was associated with a quality-adjusted life year gain of 0.09 years over a lifetime horizon, at an incremental cost of -€558 versus adalimumab. Results of various scenario analyses and probabilistic sensitivity analysis generally were consistent with the base case analysis. Conclusion: This analysis suggests that baricitinib is a cost-effective treatment option compared to adalimumab for Spanish patients with moderately-to-severely active RA and a previous inadequate response or intolerance to csDMARD therapy.
Keywords: JAK inhibitor; adalimumab; baricitinib; cost-effectiveness; rheumatoid arthritis.