Biologic disease-modifying antirheumatic drugs (bDMARDs) are prescribed sequentially in the treatment of rheumatoid arthritis (RA). Healthcare decision makers continue to debate their use, mainly because of their high costs. Our aim was to perform an economic evaluation for France of bDMARD sequences for treatment of moderate-to-severe RA after inadequate response or intolerance to conventional DMARDs (eg, methotrexate).
A discretely integrated condition event simulation was developed to track the course of patients from first bDMARD through switches to further lines in a sequence. The model included 11 events, 91 conditions, and 21 controlling equations. Inputs were obtained from a meta-analysis of clinical trials, a French registry, national drug lists, and databases. Survival, time with minimal activity, quality-adjusted life-years (QALYs), and total costs were output. Structural and probabilistic sensitivity analyses were conducted.
Sequences starting with etanercept biosimilars (ETB) cost less, with ETB-abatacept-infliximab the least expensive: the mean lifetime discounted total cost was €116 912 per patient, with a mean of 11.166 QALYs. Most other strategies were dominated or led to small QALY gains (0.0008-0.0329). Only ETB-tocilizumab-abatacept made it onto the efficiency frontier, but at €955 778 per QALY gained. These results were confirmed in several scenarios and uncertainty analyses.
Given minor differences in QALYs gained between bDMARD sequences with large cost differences, starting with biosimilars was more efficient than starting with branded products. Our model and findings should provide French and other decision makers with useful tools to address the challenges of comparing sequences of treatments for RA.