Capecitabine/Docetaxel Is More Cost Effective Than Docetaxel Alone in Pretreated Disease

SYDNEY, Australia—Capecitabine (Xeloda) plus docetaxel (Taxotere) is a cost-saving treatment for patients with advanced breast cancer previously treated with an anthracycline-containing regimen, results of an economic analysis suggest. The combination, shown in a pivotal randomized trial to provide a significant survival benefit over docetaxel alone in advanced breast cancer, is also associated with a decrease in total treatment costs, according to Carlene Todd, health economist with Roche Products Pty. Ltd., Sydney, Australia.

"It’s very rare with a new oncology product to have a survival gain and a cost saving," Ms. Todd said. "Usually, there is an additional cost associated with the addition of a therapy to an existing treatment."

Since November 2002, capecitabine/docetaxel combination therapy has been listed on the Australian Pharmaceutical Benefits Scheme (PBS) for advanced breast cancer patients who failed anthracycline-containing chemotherapy. The PBS includes more than 500 drugs subsidized by the Australian government. To be listed, a drug must be both efficacious and cost effective, Ms. Todd explained.

Based on Phase III Trial

The pharmacoeconomic analysis of capecitabine/docetaxel was based on results of the recently published randomized phase III clinical trial including 511 patients with anthracycline-pretreated advanced breast cancer (O’Shaughnessy J, et al: J Clin Oncol 20: 2812-23, 2002). The trial compared combination therapy (capecitabine 1,250 mg/m² twice daily for 14 days, plus docetaxel 75 mg/m² every 3 weeks) vs docetaxel alone (100 mg/m² every 3 weeks).

Capecitabine/docetaxel increased overall mean survival by 2.7 months vs docetaxel alone (P < .05). The mean duration of therapy was also longer for the combination (129 vs 98 days) reflecting a time to progression 2.4 months longer than with docetaxel alone (P < .001).

Investigators prospectively collected pharmacoeconomic data on parameters including number of infusions, drug dosage, and hospitalizations. Unit costs were based on published estimates for Australia.

Total cost in Australian dollars ($A), per patient per course of treatment, was $A18,581 for the combination, vs $A18,739 for docetaxel alone. (At the time of the study, $A1 equaled $0.55 US.)

This represented a saving of $158 Australian or approximately $89 US. The total cost figure included drug acquisition, preparation and administration, outpatient/specialist visits, and hospitalizations or consultations for adverse events.

What Drove Costs Down?

The main driver of cost reduction, according to Ms. Todd, was a lower cumulative dose of docetaxel in the combination arm (658 mg vs 848 mg for docetaxel alone), despite a longer duration of treatment. The savings came despite more hospitalizations for adverse events in the capecitabine/docetaxel arm (143 vs 136 for docetaxel alone).

Cost-effectiveness analysis revealed a gain of 0.22 discounted life-years per patient treated with combination therapy, and a gain of 0.20 progression-free life-years gained. "When we adjusted a number of factors in a sensitivity analysis, we still found that the result was favorable," Ms. Todd. said

This further analysis included adjusting the following: overall survival and time to progression according to 95% confidence intervals; the average docetaxel dosage used in Australian clinical practice (86.5 mg/m²), and equivalent dosages in each arm (75 mg/m²).