Post hoc economic analysis of temozolomide versus dacarbazine in the treatment of advanced metastatic melanoma

Abstract

Purpose: To determine the potential economic implications resulting from oral temozolomide (TEM) compared with intravenous (IV) dacarbazine (DTIC) for metastatic melanoma.

Patients and methods: We performed a cost-effectiveness (CE) analysis using hazard ratios (HRs) from the phase III (Schering I95-018) trial comparing TEM 200 mg/m(2)/d orally for 5 days every 28 days with DTIC 250 mg/m(2)/d IV for 5 days every 21 days. Sensitivity analyses assessed a range of TEM's efficacy and costs, direct nonmedical costs, and the DTIC schedule.

Results: The trial found an overall survival trend favoring TEM; median survival times of patients treated with DTIC and TEM were 6.4 and 7.7 months, respectively (HR = 1.18; 95% confidence interval [CI], 0.92 to 1.52; intention to treat, P =.20). The mean increase in survival of TEM over DTIC was 1.1 months. The projected average costs per patient were greater with TEM than DTIC ($6,902 v $3,697, respectively). The incremental CE ratio using TEM was $36,990 per life-year or $101 per day of life gained. The CE ratio's 95% CI ranged from -$65,180 (DTIC is more effective) to $18, 670 per year of life gained. The CE ratios decreased 50% if direct nonmedical costs were included and increased 50% if DTIC's efficacy was unchanged if given as a single daily dosage. Sixty percent of simulations found TEM with a CE threshold of less than $50,000 per life-year gained.

Conclusion: Although the base-case efficacy of TEM compared with DTIC was not statistically significant, its associated incremental CE would be comparable with many interventions. TEM for metastatic melanoma illustrates the tension confronting providers choosing between similar agents that markedly differ in convenience and costs.