OBJECTIVES: To analyse the cost-effectiveness of biosimilar tocilizumab and other available biological or targeted synthetic DMARDs (disease modifying antirheumatic drugs) versus biosimilar infliximab for the treatment of patients suffering moderate or severe rheumatoid arthritis in Spain.

METHODS: A Markov model including the following health states: remission of the disease, low activity, moderate activity, high activity, and death; with a lifetime horizon and from the healthcare system perspective. The model included abatacept, biosimilar adalimumab, baricitinib, certolizumab, etanercept, filgotinib, golimumab, infliximab, rituximab, sarilumab, reference and biosimilar tocilizumab, tofacitinib, and upadacitinib. Efficacy measured by Disease Activity Score (DAS) 28 was retrieved from meta-analysis and additional data from clinical trials; Spanish pharmacological costs were obtained from a hospital pharmacy nationwide database, and ancillary healthcare costs from regional published tariffs for medical resources. Deterministic and probabilistic analysis were run, and the incremental cost-effectiveness ratio (ICER) for the cost per percentage of remission and cost per quality-adjusted life year (QALY) gained were calculated.

RESULTS: The lifetime cost of biosimilar tocilizumab was the cheapest of all the therapeutic alternatives 183,741€ vs certolizumab being the most expensive 201,972€. Percentage of remission and QALYs showed better results for biosimilar adalimumab, certolizumab, reference tocilizumab, biosimilar tocilizumab, sarilumab, tofacitinib, upadacitinib, baricitinib, filgotinib, and abatacept than biosimilar infliximab. ICERs showed biosimilar tocilizumab as the only therapeutic alternative superior against biosimilar infliximab, being dominant in both cases.

CONCLUSIONS: Biosimilar tocilizumab has proven to be a cost-effective alternative for the treatment of rheumatoid arthritis patients, even against the least expensive available biological or targeted synthetic DMARD comparator in Spain in a lifetime-horizon perspective.