A cost-utility analysis of second-line chemotherapy in metastatic breast cancer. Docetaxel versus paclitaxel versus vinorelbine

The aim of this study was to determine the incremental effectiveness, the incremental health-related quality of life (differences in quality-adjusted progression-free survival between treatments), the incremental cost and the incremental cost-effectiveness and cost-utility ratios, for docetaxel, paclitaxel and vinorelbine, when these drugs were used as second-line treatment in patients with metastatic breast cancer. In the absence of comparative direct evidence of the relative efficacy of docetaxel, paclitaxel and vinorelbine in this setting, a model was designed to determine the effects of the 3 interventions on health outcome and cost. A Markov process model, based on 53 disease states, was thus constructed to evaluate the socioeconomics of the 3 treatment regimens. The model allows assessments from the start of second-line chemotherapy until death. Costs were evaluated from the combined view of the healthcare system and the patient. Direct nonmedical and indirect costs were excluded. Consumption per episode of care was estimated by retrospective analysis of 153 medical reports from 5 different hospitals. Hospital costs were allocated values from the national accounting costs by diagnosis-related group (DRG). The content of the health states was based on the multiattribute health states classification system (MASH). Preference values were assigned by application of a standard reference lottery using 20 oncological nurses as proxies for the patients. The health-related quality-of-life score was used as a quality adjustment weighting factor to calculate quality-adjusted progression-free survival associated with the 3 different regimens. Docetaxel reduces the time spent in progression, decreases the number of complications due to progressive disease and thereby provides better quality of life. It provides a benefit of 57 disease- and discomfort-free days compared with vinorelbine and 22 days compared with paclitaxel. Docetaxel may be thought of as self-financing as a result of savings in hospital admissions, providing net savings of 6800 French francs (FF; 1993 values) compared with expenditure associated with vinorelbine treatment and FF700 compared with the equivalent figures for paclitaxel.