To support an evidence-based decision regarding the inclusion of the anti TNF's adalimumab, etanercept or infliximab to the National Formulary of Uruguay for the treatment of psoriatic arthritis, in patients who did not respond to first-line treatment.

We perform a cost-utility evaluation using a Markov model, to estimate the incremental costs and quality-adjusted life years (QALY) gained with each of these biologic drugs compared with palliative care only. The model considered the perspective of the National Health System, with a time horizon of 40 years.

Under base-case assumptions, infliximab results in an incremental cost-effectiveness ratio (ICER) of United States Dollars (USD) 47,294 compared to palliative care only. Adalimumab was extendedly dominated and etanercept was dominated. However, infliximab requires intravenous administration which could significantly reduce access to treatment, thus producing inequities for patients from different regions. The probabilistic sensitivity analysis shows that all biologics had null probabilities of being cost-effective considering a willingness-to-pay (WTP) threshold of one time the gross domestic product per capita of Uruguay per QALY.

In our analysis from the perspective of the National Health System, the use of biologic drug treatments for psoriatic arthritis results in an ICER above the WTP ceiling proposed by the World Health Organization. Reduction of drug prices could bring more favorable cost-effectiveness results.