Patient preferences for biologic agents in rheumatoid arthritis: a discrete-choice experiment.

Objectives: To assess patients' preferences for rheumatoid-arthritis treatments with biologic agents using a discrete-choice experiment. Methods: A discrete-choice experiment was conducted with adult rheumatoid-arthritis patients who had never been treated with biological agents from two university hospitals-public and private-in Buenos Aires, Argentina. We evaluated preferences for seven treatment attributes (with two to three levels each): effectiveness, mode of administration, frequency of administration, local and systemic adverse events, severe infections, and out-of-pocket costs. A probit regression model was used to analyze the relative importance of rheumatoid-arthritis treatment attributes. We estimated attributes' relative importance and their 95% confidence intervals. Results: Survey responses from 240 patients with rheumatoid arthritis receiving conventional disease-modifying antirheumatic drugs were included in the study. All tested biological agents' attributes significantly affected the choice of treatment. Attributes' relative importance in decreasing order was the following (mean, confidence interval 95%): cost, 0.81 (0.69-0.92); systemic adverse events, 0.66 (0.57-0.76); frequency of administration, 0.61 (0.52-0.71); efficacy, 0.42 (0.32-0.51); route of administration, 0.41 (0.30-0.52); local adverse events, 0.40 (0.31-0.49); and serious infections, 0.29 (0.22-0.37). Conclusions: Different treatment attributes had a significant and different influence in rheumatoid-arthritis patients' choice of biological agents. This type of study can not only inform about patients' preferences but also about the trade-offs among different possible treatments or process-related attributes.