Cost-effectiveness analyses of docetaxel versus paclitaxel once weekly in patients with metastatic breast cancer in progression following anthracycline chemotherapy, in Spain.

OBJECTIVES

Our aim was to evaluate the cost-effectiveness of docetaxel versus weekly paclitaxel regimen in patients with metastatic breast cancer previously treated with anthracycline from the Spanish National Health Service (NHS) perspective.

METHODS

A Markov model with a 21-day cycle duration was developed to estimate total treatment-related costs and clinical benefits over 5 years of docetaxel (100 mg/m²) and weekly paclitaxel (80 mg/m²). Patient data were obtained from the Randomized Phase III Study of Docetaxel Compared with Paclitaxel in Metastatic Breast Cancer (TAX- 311) and Anglo-Celtic IV trials. Utilities were obtained from literature, and unitary costs (€2009) from a Spanish health-cost database and the Catalogue of Medicines. Cost and benefits [life-years gained (LYG) and quality-adjusted life years (QALY)] were discounted at 3%. Sensitivity analyses were performed.

RESULTS

Docetaxel yields higher health benefits (1.83 LYG; 1.08 QALY) than paclitaxel (1.46 LYG; 0.84 QALY). Global costs (treatment, concomitant medication, adverse events management, progression, best supportive care, and end of life phase) per patient were €20,052 and €9,982 with docetaxel and paclitaxel, respectively. Incremental cost-effectiveness ratio (ICER) of docetaxel versus paclitaxel was €190/LYG and €295/QALY. Based on a €30,000/QALY threshold, docetaxel has 99% probability of being cost-effective. ICER was mostly sensitive to hazard ratio (HR) (when varied from 1.46 to 1.09; €3,517/ QALY), discount over the ex-lab price of Taxol® (75%; €6,396/QALY) and granulocyte colony-stimulating factor (G-CSF) prophylactic treatment (when administered in 60% of cycles instead of 100%; cost saving). Variations in other inputs, such as time horizon (3-10 years), discount rate (0-5%), or adverse event cost (± 25%) were shown not to have relevant influence on the results.

CONCLUSION

Compared to weekly paclitaxel, docetaxel therapy is cost effective for treating metastatic breast cancer patients.