Pharmacoeconomic study of herceptin® (trastuzumab) for breast cancer patients

Abstract

50Herceptin IV. For example, the drug dosage does not depend on the patient's body weight and a standard fixed dose of 600 mg/5 mL is used for each SC administration that is much easier compared to IV formulation. When Herceptin IV is used, the dosage is calculated based on the patient's body weight leading to loss of medicinal substance, at least in 15% of cases. This loss is due to "disposal" of the drug remained in the vial, which may not be used as drug is compromised [9,13]. The next important advantage of Herceptin SC compared to IV formulation is time saving which has been defined for Russia in the study "Time&Motion" [16]. This saving was considered from the point of view of both patients and medical staff. Due to detailed description of time spent on each procedure performed with the patient in the hospital, it was possible to express time saving in monetary units, which clearly demonstrated the benefit of Herceptin SC. Study methodologyThe study compared pharmacoeconomics of Herceptin in a new formulation for subcutaneous administration versus intravenous formulation for Breast cancer patients in conditions of the equal prices of these drugs. These alternative regimens were used for one year. Herceptin IV dosages depended on the patient's body weight and were 8 mg/kg (single loading dose) and 6 mg/kg (maintenance dose) (17 infusions). Herceptin SC regimen consisted of 18 injections at a standard dose independent of the patient's body weight. Then, based on the costs associated with diagnosis, treatment and pharmacotherapy, the expenses were analysed to determine the total cost of the therapies compared. The expenses analysis also took into account the costs related to patient's hospitalization, services provided by the medical personnel and mandatory testing for HER2-expression [6].Summary: Breast cancer is a global problem due to its wide prevalence which is increasing every year. The comparative pharmacoeconomic study of Herceptin in subcutaneous and intravenous formulations was conducted for optimization of drug supply for this nosology. Direct medical expenses without taking into account the drug price were compared. As a result of pharmacoeconomic evaluation of the alternative treatment options, it was established that subcutaneous Herceptin saves 39,806 roubles per patient during one treatment year due to the cost differences related to administration, medical staff, as well as hospitalization. Moreover, when IV formulation is used for one treatment year per patient, the medicinal substance is lost due to « throwing out» the remaining part of the drug in the vial, which may not be used in connection with breach of sterile dosage forms. The loss is as high as 166,208 roubles; this translates into 11% monetary loss from the whole treatment cycle.