To analyze the cost-effectiveness of two common treatment strategies in Iran, comparing infliximab plus methotrexate with tocilizumab plus methotrexate in patients with rheumatoid arthritis with inadequate response to traditional disease-modifying antirheumatic drugs.
A multistage Markov decision model was applied to assess the incremental cost-effectiveness ratio (ICER) of a tocilizumab-containing regimen versus an infliximab-containing regimen over a 5-year time period. In the case of no response, we assumed that patients switched to the next treatment (adalimumab, rituximab, or supportive care) in sequence for each strategy. We considered major cost items, such as direct medical costs and direct nonmedical costs, from a payer (patients and third-party payers) perspective. A deterministic sensitivity analysis was conducted to assess the robustness of the model results over the uncertainty of key parameters.
In the base-case analysis, the ICER of the tocilizumab-containing regimen was US $60,800 per quality-adjusted life-year as compared to the infliximab-containing regimen. In the sensitivity analysis, changes in the price of the drugs by generic substitution, in utility scores, and in discount rate did not change our overall conclusions. Among all inputs to the primary study and the sensitivity analyses, however, the price of tocilizumab had the most impact on the ICER.
Although tocilizumab and methotrexate provide a larger gain in quality-adjusted life-years, their current price is quite high as compared with those of our other interventions. Therefore, a regimen containing tocilizumab is not cost-effective as compared with an infliximab-containing regimen for patients with rheumatoid arthritis in Iran.