The pharmacoeconomic analysis of the cost efficiency of trastuzumab in the adjuvant therapy of HER2 + early breast cancer

Abstract

Breast cancer (BC) is the first among all oncological diseases in women and is one of the main causes of female mortality worldwide, including in Ukraine. The HER2 + subtype of breast cancer is characterized by the most unfavorable prognosis. The targeted drug trastuzumab significantly improves the 10-year survival rate of patients with HER2 + breast cancer, but at the same time significantly increases the cost of treatment. Aim. To assess pharmacoeconomically the adjuvant therapy of the early stage of HER2 + breast cancer with trastuzumab (Herceptin® medicine) from the perspective of the Ukrainian healthcare system. Materials and methods. The method of analytical modeling by Markov was used. Modeling was carried out on the basis of the results of a randomized, multicenter open clinical trial of phase III HERA. The time horizon of the model is 10 years. As an alternative to trastuzumab the standard adjuvant therapy regimens for breast cancer given in the current Protocol for the care of breast cancer patients were considered. According to the results of modeling by Markov the methods of “cost-effectiveness” and “cost-utility” were used. The efficiency criterion was the life years gained (LYG). The utility criterion was QALY. The cost of direct medical expenses was taken into account. The cost structure was determined by the Protocol. The cost of drugs was determined by the Register of the Ministry of Health of Ukraine as of 08/07/2019. The cost of medical services was determined by price lists. The cost of correcting side effects of chemotherapy was also taken into account. The discount was 3 % annually. The analysis of the sensitivity of the results was conducted to change the price of trastuzumab and the price of drugs of alternative adjuvant therapy regimens. Results. According to the modeling the average life expectancy of patients with HER2 + breast cancer in the trastuzumab group was 7.32 years, in the standard chemotherapy group it was 6.43 years. In the trastuzumab group, patients received 6.72 QALYs, while in the standard chemotherapy group – 5.80. The adjuvant therapy with trastuzumab gave the patients an additional 0.89 LYG and 0.92 QALY. The costs of treatment during the study in the trastuzumab group averaged 627115.5 UAH per one patient, in the group of the standard chemotherapy it was 501939.6 UAH. The incremental ratios ICER (the cost of 1 additional year of life) and ICUR (the cost of 1 additional QALY) were 140,833.8 UAH and 136088.8 UAH, respectively. Conclusions. The targeted drug trastuzumab is a medicine for the adjuvant therapy of the early stage HER2 + breast cancer with the evidence-based effectiveness. The adjuvant therapy regimen for HER2 + breast cancer with trastuzumab compared to the standard adjuvant chemotherapy with HER2 + is expensive, but gives better results. It gives an average of an additional 0.89 years of life and 0.92 QALY. The pharmacoeconomic analysis based on modeling by Markov and “cost-effectiveness” and “cost-utility”calculations allows considering the early stage adjuvant therapy of HER2 breast cancer with trastuzumab (Herceptin®) as an economically feasible medical technology in the healthcare of Ukraine today.