OBJECTIVES: In the Brazilian private healthcare system, coverage for oral therapy is not mandatory. The association of lapatinib and capecitabine (LAP/CAP), both orally administered, is an effective combination for the treatment of patients with metastatic HER2 positive breast cancer (MBC-HER2+) after progression to trastuzumab, but is not frequently used. The objective of this study was to evaluate treatment patterns and associated costs of MBC-HER2+ after progression to trastuzumab, under the perspective of the Brazilian private healthcare system and to calculate the economic impact associated with using LAP/CAP for this population. METHODS: Evidencias® database contains data related to around 3,000,000 lives covered by private health plans in Brazil. In this database, patients diagnosed with MBC-HER2+ and treated with chemotherapy after failure to trastuzumab were selected. For every patient, treatment costs were calculated considering drug costs only. Three cost scenarios were estimated: i) real-life chemotherapy (CT) used by patients; ii) hypothetical use of LAP/CAP; iii) hypothetical use of trastuzumab associated to capecitabine (TRAST/CAP). RESULTS: A total of 182 patients were included in the analysis. Average treatment duration was 10.5 weeks (95% CI: 8.9 - 12.2). Twenty-two treatment protocols were identified after failure to trastuzumab, mainly: paclitaxel (27%), docetaxel (20%) and vinorelbine (14%). The average cost per patient were R$19,114.68, R$25,977.61 and R$39,437.26, in the CT, and projected LAP/CAP and TRAST/CAP scenarios, respectively. Considering the results segmented by CT protocol, LAP/CAP costs were lower than CT for patients treated with paclitaxel associated or not to gemcitabine, among others. For all patients, projected costs with LAP/CAP were lower than TRAST/CAP. CONCLUSIONS: Patients treated with CT, eligible for treatment with LAP/CAP or TRAST/CAP, had lower treatment costs when compared to LAP/CAP or TRAST/CAP. In some specific CT combinations, however, LAP/CAP may result in lower costs, thus being considered an economically viable alternative.