OBJECTIVES: The standard treatment OF HER2+ breast cancer in Ecuador is Trastuzumab IV + Chemotherapy, however, the pharmaceutical formula Trastuzumab Subcutaneous (SC) has been shown to have the same efficacy, treatment regimen and a higher patient preference, which is why an economic analysis is fundamental for decision making METHODS: We opted for a Budget Impact to reflect the savings that the incorporation of the pharmaceutical formula SC would generate to Ecuador. The analysis proposes a difference of 6% between the price of Trastuzumab IV ($1821.94) and Trastuzumab SC ($1712.62), in addition, it includes administration costs (USD, 2015) for patients between 40 and 59 years old with an average weight of 66.7 kg (95% CI 66kg: 68kg) for a population of 515 people (Globocan 2012) and a time horizon of three and five years. Due to the fact that in Ecuador there is no available data on waste management and vial sharing, the following article was used as guide ¨Drug waste minimization and cost containment in Medical Oncology: Two year results of a feasibility study¨(Fasola G et al., 2014) RESULTS: Considering an average of 7% of vial waste in the first year and a 3.5% of vial waste from the second year on, Trastuzumab IV represents an investment of $15710806 in the first year and of $15199073 from the Second year while Trastuzumab SC represents an investment of $14842096 per year. The incorporation of Trastuzumab SC would generate savings of $868716 the first year and of $356978 from the second year on. Savings of $ 1582665 would be generated in 3 years and of $ 2,296,620 in 5 years CONCLUSIONS: The reimbursement of Trastuzumab SC would generate substantial savings to Ecuador ($2296620 in five years) as well as a more efficient drug management considering a mean price difference of 6% between SC and IV.