OBJECTIVES: New therapies have recently been introduced for the treatment of mRCC. The objective of this analysis was to evaluate the cost-effectiveness of two such treatments, temisirolimus (TEM) and sunitinib (SUN) for the management of poor prognosis mRCC patients in Portugal. METHODS:   A Markov model simulating disease progression in poor prognosis mRCC was developed to estimate cost-utility of TEM vs. SUN over 3-year time horizon. Patients in the model move through progression free survival (PFS), disease progression, or death. Transitions between health states were estimated from Weibull curves fitted to overall survival (OS) and PFS of interferon (INF), the common comparator in TEM and SUN trials.  Hazard ratios of treatment effect of TEM and SUN to INF were then applied.  PFS and OS were based on poor prognosis patient population for TEM and SUN. On-treatment utility estimates were based on EQ5D data. Local costs of drug, administration and medical follow-up were used.  Analyses were run considering the uncertainty around PFS and OS measures using model generated 95% CI. Probabilistic sensitivity analysis was conducted to evaluate impact of assumptions on input parameters RESULTS:   The mean estimated total cost and QALYs for TEM was €18,757 (range €11,646 to €31,141) and 0.584 yrs. (range 0.388yrs. to 0.794yrs.).  While for SUN the mean estimated total cost and QALYs was €14,323 (range €4,958 to €38,875) and 0.381 yrs. (range 0.125yrs. to 0.831yrs.).  The mean incremental cost per QALY for TEM vs SUN was €21,783. Within the ranges of uncertainty, 20% of the time TEM could dominate SUN and 76% of the time TEM was more costly and more effective.  CONCLUSIONS:   TEM is projected to be cost effective compared to SUN in management of poor prognosis mRCC patients.