Pharmacoeconomic analysis of lapatinib treatment in metastatic breast cancer with HER2+ overexpression

According to the World Health Organization, breast cancer is the most common form of cancer in women worldwide.The steady increase in the prevalence of breast cancer, followed by an increase in the state budget expenditures on drug supply for this category of patients, determines the relevance of pharmacoeconomic evaluation of treatment of HER2-positive breast cancer using a combination of lapatinib and capecitabine and trastuzumab emtansine monotherapy.A subgroup analysis of the therapeutic outcomes in patients with HER2+ breast cancer conducted by the EMILIA study failed to find a statistically significant difference in median overall survival in patients receiving either trastuzumab emtansine or a combination of lapatinib and capecitabine as second-line treatment, or in patients with non-visceral metastases.Analysis of overall survival of the entire population of patients in the EMILIA study revealed that trastuzumab emtansine is more effective than a combination of lapatinib and capecitabine.Despite this, NICE does not recommend treatment with trastuzumab emtansine due to high cost of treatment.The EMILIA study results were used as a basis for pharmacoeconomic models for HER2+ breast cancer therapy, using such methods of pharmacoeconomic analysis as budget impact analysis, cost-effectiveness analysis, and costminimization analysis for these subgroups of patients.Result of budget impact analysis revealed that the use of the lapatinib and capecitabine combination can reduce health system expenditures by 3,985,271 rubles per patient per year or by 5,851,484 rubles over three years per one patient, which allows treating 4 additional patients given the fixed budget.Cost-effectiveness ratio of lapatinib + capecitabine equals to 869,705 rubles and 3,461,960 rubles with LYG and QALY as efficacy endpoints, respectively, which identifies this therapy as cost-effective in pharmacoeconomic terms.Cost-minimization analysis of lapatinib+capecitabine patient groups in the second-line treatment, and a group of patients with non-visceral metastases showed that the use of this treatment may reduce costs by 78% in comparison with trastuzumab emtansine.