The issue of comparators in economic evaluations of biologic response modifiers in rheumatoid arthritis

Over the last decade, a number of biologic response modifiers (BRMs) have emerged and transformed rheumatoid arthritis (RA) management. Due to their relatively high costs, economic evaluations have attempted to determine their place in the RA treatment armamentarium. This article reviews three key areas where changes to the treatment paradigm challenges findings of existing economic evaluations.

We performed a literature search of economic evaluations examining BRMs approved for use in North America for RA. Only economic evaluations that examined relevant direct costs and health outcomes were included. Data were extracted and summarised, then stratified by patient population and comparators. Reported incremental cost-effectiveness ratios (ICERs) were compared across studies.

It appears that tumour necrosis factor (TNF) alpha inhibitors are less cost effective compared to disease-modifying anti-rheumatic drugs (DMARDs) for first-line treatment. In addition, it appears that treatment with a TNF alpha inhibitor in patients who were refractory to previous DMARD therapies is more cost effective, compared to switching to another DMARD. Finally, after an inadequate response to a TNF alpha inhibitor, it appears that therapy with rituximab is more cost effective than treatment with another TNF alpha inhibitor or abatacept.

It is important to acknowledge that cost effectiveness depends on which comparators are included in the analyses and the evidence for the comparators. The most typical comparator in the studies was traditional DMARDs, mainly methotrexate. However, as more BRMs come into the market and new clinical evidences emerge on the comparative effectiveness of BRMs, new economic evaluations will need to incorporate this information such that reimbursement decisions can be fully informed regarding relative value.