Evaluating Trastuzumab and Lapatinib's Economic Impact in the Treatment of Metastatic Breast Cancer in Veneto Region Cohort

Objective: To evaluate the impact of multitargeted tyrosine kinase inhibitors (TKI) considering 1st and 2nd line treatment for a full period of 3 years in the eligible patients of Veneto Region. Methods: A Markov state decision model was selected to evaluate the cost impact of sunitinib and sorafenib use for a lapse of time of three years in Veneto public hospitals, considering transition probabilities from three different states and by comparing the expected deaths and the monthly survival rates in treatment and no-treatment groups. Results: From the initial cohort of 357 patients eligible for sunitinib treatment, stable ones (139) were considered in order to evaluate the impact of the multitargeted agent on overall progression of the disease. Results showed that a smaller portion of patients receiving sunitinib transited from a stable to a progressive state, with respect to the patients who were not receiving sunitinib. The cost of 6 months treatment with sunitinib reached a median value of 2532666€, increasing till 3607807€, as cumulative amount at 12 months. Costs after the 1st year flattened around the same figure (3800000€) due to the transition towards death or 2nd line treatments. Discussion: the costs of the first 6 months therapy with sunitinib have a very high impact on public health expenses in the Regione Veneto. 2nd line treatment with sorafenib instead increased overall expenses of a reduced proportion, due to the small proportion of patients undergoing this treatment and the relative inferior cost of the drug. Conclusion: From what came out from our simulated model on costs borne by the SSN for the treatment of patients with mRCC, we can conclude that they are effective on the progression of the disease the greatest impact being the cost for the 1st line pharmacological treatment.