Budget impact model of subcutaneous compared with intravenous trastuzumab in the treatment of HER-2 positive breast cancer in the Brazilian Private Healthcare System

Abstract

Objective: To estimate the budgetary impact of subcutaneous trastuzumab, compared with intravenous trastuzumab, in the Brazilian Private Healthcare System (PHS), to treat early and metastatic HER-2 positive breast cancer. Methods: Budgetary impact analysis was performed in PHS perspective. For early breast cancer, treatment options were trastuzumab monotherapy, and trastuzumab plus paclitaxel or docetaxel, after adjuvant chemotherapy. For metastatic breast cancer, trastuzumab was combined with docetaxel or paclitaxel in the first line, and it was given in monotherapy in the second line. For both, a comparison of switching from intravenous to subcutaneous therapy was made. A survey was performed with 28 health maintenance organizations to map fees and sources used for reimbursement of drugs, materials and procedures. Direct medical costs were included. Time horizon was 5 years and market share of subcutaneous trastuzumab vary from 20% to 100%. Results were presented according to size of health maintenance organizations and a deterministic sensitivity analysis was conducted to analyze model robustness. Results: In 5 years, 31,589 breast cancer patients were estimated for the PHS, 284 patients for big, 30 patients for medium, and 6 patients for small HMOs. The progressive uptake of subcutaneous trastuzumab, compared with intravenous formulation, can save up to 962,7 mBRL, 14,5 mBRL, 1,5 mBRL and 0,2 mBRL, respectively. Materials and support procedures along with medical fees were the most sensitive parameters. Conclusion: Compared with the intravenous administration, subcutaneous trastuzumab can save up to 962,7 mBRL costs in the breast cancer treatment in the Brazilian PHS.