OBJECTIVES: This study evaluated the cost-effectiveness of pegvisomant compared to octreotide-LAR and the incremental Budget Impact Analysis (iBIA) from the public perspective in São Paulo State Health Secretariat (SHS/SP).  METHODS: The economic evaluation assumed octreotide-LAR to be first line treatment as (recommended to acromegaly Ministry of Health Brazilian guideline). In certain clinical conditions patients who fail to achieve biochemical control will receive octreotide-LAR staggered dose (off-label use). This population was used for the analysis, and compared to a population of patients with acromegaly treated with pegvisomant. To estimate costs and treatment outcomes, a Markov model was developed, representing the control rate of patients treated with pegvisomant or  maintained dose staggered octreotide-LAR. All patients entering the model who were unresponsive to the maximum octreotide-LAR dose based on the transition risk and according to control or non-control of disease, patients could transition to one of the following states: control; non-control and death (absorbing state). A time horizon of 35 years was assumed and a discount rate of 5% per annum was applied. The outcomes of interest were: "years of life" and "years living with disease control”. To estimated number of SHS/SP eligible patients, the epidemiological demand method was applied that resulted in 210 patients (2015).  RESULTS: The iBIA was estimated to increase by 24.87% of current spending, if pegvisomant is reimbursed by the government in SHS/SP. for "year of life" and "years living with disease control” were 0.46 and 1.37 years, respectively, and for pegvisomant saving BRL 313,599.84. The final result did not change; the sensitivity analysis demonstrated the model robustness. CONCLUSIONS: Pegvisomant is a dominant technology compared to octreotide-LAR under the SHS/SP and it may represent a feasible treatment option for patients with acromegaly in the acromegaly treatment in SHS/SP.